The Sewing Place

Machine Talk => Vintage Machines => Topic started by: Madame Cholet on September 14, 2017, 21:54:13 PM

Title: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on September 14, 2017, 21:54:13 PM
I found this on Gumtree recently - the seller was asking £5 for it   :D
It is a Bernina 840 Favorit that was run on a table with an industrial motor, and had sat unused and forgotten in a garage for many years.
So there's no motor and the mechanism was locked up solid, but for £5 I couldn't resist  :D :D :D :D :D <3
I'm looking forward to de-gunking the innards and getting everything moving again - watch this space!

(https://i.imgur.com/n84cVCKl.jpg)

(https://i.imgur.com/UPXaFnAl.jpg)

(https://i.imgur.com/Kv2H0g0l.jpg)

[Edited to amend thread title and add photos from Imgur]
Title: Re: Bernina Favorit 840
Post by: arrow on September 14, 2017, 22:03:15 PM
I've had my hands on a 740 Favorite, and another flatbed version, but I can't remember the model number. There are two types of bobbins on the flat beds, and I think you have the one with the rotary hook and race, not the occilating. It's extra speedy and quite tought as I'm sure you aware of. They are described as industrial others semi-industrial, some call them artisan, but it's the same machine either way. I hope you find a motor for it.
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 14, 2017, 22:19:18 PM
Yes Arrow you are right, mine has the rotary hook and race.
Interestingly there is also an oil pan beneath the flatbed. I took the cover off to have a look, and realised it was an oil pan when a whole load of oil came pouring out. The oil was so old it was brown.
It looks as though it will fit in my Singer treadle base, so it might be fun to set it up as a treadle machine in the short term!
It had been used with an industrial motor; I am not sure how I would attach a domestic motor to it, as there does not appear to be any motor mounting points on the casing.
It's early days yet though, I need to get the mechanisms freed up first.
The seller assured me it was working when it was put away, and that it was complete, so fingers crossed I can get her sewing again.
I do love vintage Berninas - I have 6 now  8)
Title: Re: Bernina Favorit 840
Post by: arrow on September 15, 2017, 00:40:43 AM
You might be able to find a motor you can fit under the table, various Bernina parts should turn up, even if they aren't as plentiful as some others. I have seen some of the older Berninas in treadle cabinets, not often at all, but it looks like the 500 numbers and probably even 730s could be ordered as treadle. The treadle cabinets I have seen are of a the later kind, with irons painted in brown and of a more minimal design than the older. The Bernina name is sometimes in the pedal casting. I was surpised when I noticed treadles probably were made as late as the mid 1960s. It will probably be the first 840 as treadle ;- )
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 15, 2017, 10:21:56 AM
Thanks Arrow, that is really interesting information about Bernina treadles. I have never seen an original one, although I have heard of people running 717s on a Singer treadle base after removing the motor.

The good news is that this morning, after a couple of days of letting oil soak in and heating now and then with a hairdryer, the mechanism is free and is turning!
The nylon cam stack gear is intact.
All knobs and dials turn freely.

The bad news is that there seems to be an issue with the stitch width knob - when turned manually it 'springs' straight back to '1', and does not stay in position on any other setting.
Also the buttonholer dial feels loose and sloppy when turned to positions 5 and 6. I have never used an 800 series with a buttonholer dial, so I do not know if this is normal or not, but it feels odd to me.

I have not yet tested whether it sews, as there is so much cleaning yet to be done.
 8)
Title: Re: Bernina Favorit 840
Post by: arrow on September 15, 2017, 12:07:54 PM
The buttonholer dial doesn't feel sloppy as far as I know, but I don't know how they work. When you turn them you feel you are turning other parts behind there as well. This is something the Bernina yahoo group might have some info on, like a service manual, or parts lits.

This (http://www.ebay.de/itm/Liebhaberstuck-Bernina-Nahmaschine-/172835586028?hash=item283dcdbfec:g:ex0AAOSwAFNZnrB4) is the type of cabinet I'm thinking of. There's [urlhttp://www.ebay.de/itm/Bernina-Favorit-Nahmaschine-mit-Schrank-Fus-oder-Strombetrieb-/401401204818?hash=item5d75605052:g:LOoAAOSwB-1YugRO]one more[/url] on german ebay. These have both motor and treadle option. The threadles have a different hand wheel, I guess to make it easier with the leather belt. Some liked the treadle option a lot, I guess it gave them a feel for the stitch formation for some type of work. That's someting hardly any of us bother about today.
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 15, 2017, 14:10:49 PM
That cabinet is beautiful, and I especially like the key!
I really like the look of this one too, is it walnut?:
http://www.ebay.de/itm/Nahmaschine-Bernina-642-1-Made-in-Switzerland-Baujahr-1960-1962-antik/322731703556?_trkparms=aid%3D888007%26algo%3DDISC.MBE%26ao%3D1%26asc%3D46153%26meid%3Da083ab053c354089b071a2d3a8b7eb83%26pid%3D100009%26rk%3D1%26rkt%3D2%26sd%3D172835586028&_trksid=p2047675.c100009.m1982

I have the service manual, and also the parts manual, and this evening I plan to spend a few hours cleaning, oiling and investigating the stitch width knob and the buttonholer dial mechanisms.
Turning the buttonholer dial from 1 through to position 4 you can definitely feel resistance from the other moving parts behind, but turning from 4 to 5 and from 5 to 6 there's no resistance at all. Looking at the parts manual there are 3 springs involved in the mechanism. I'll check those first perhaps I think.
Title: Re: Bernina Favorit 840
Post by: arrow on September 15, 2017, 15:52:56 PM
The buttonholer on my 900 is the same as on the 830, but I have never investigated that much. You 840 must have been treated a bit harshly when it comes to cleaning and oiling, but it can usually be cleaned up and done right. It's a  model worth spending a bit of time and effort on at least.

The veneer in the door looks like birch or beech root, it's used for the pattern in the grain. It's often given the pale look by leaving it unstained and just trated with layers of transparent lacquer. Ash can have a similar type pattern in the grain. I don't think it's walnut, because it doesn't turn yellow with age in the same way as birch or beech.
Title: Re: Bernina Favorit 840
Post by: Roger on September 15, 2017, 21:47:42 PM
Hi Madame,

That is quite a machine! Most industrial motors are 'Clutch' but these aren't very efficient and can have user quirks... like gradually accelerating without increasing pressure. The more recent approach is the servo motor, these are more efficient and have higher torque. And cost about £100,
Clutch motors can be had more cheaply because a lot of people are upgrading to servo motors.

If you're looking at industrial motors
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 15, 2017, 22:20:30 PM
The blond birch/beech root veneer on that cabinet is utterly stunning, I keep going back to the German ebay ad to look at the photos! It looks more like an elegant drinks cabinet than something built to house a sewing machine. Gorgeous. I had no idea the vintage Bernina cabinets are so utterly beautiful  <3
Arrow thank you for enlightening me!

I think I may have worked out what the issue is with the 840 regarding the stitch width knob, although I could well be wrong as I am obviously not a Bernina tech just someone who knows very little but enjoys playing around with the insides of sewing machines  8)
I don't know what the proper names are for the parts I am talking about, and my account is rather rambling, so please forgive me for that. If anyone can shed more light on what I am trying to fix here I would be very grateful!

I had a good look at my little Bernina 807 minimatic, and the stitch width knob set-up on it looks to be more or less the same as on the 840.
It seems to be essentially a slider mechanism, consisting of a channel and a sliding 'block' which slides up and down the channel. The 'block' connects to a linkage attached to the needle bar, so as the block moves up and down the slider channel - when the stitch width knob is moved - the needle bar moves correspondingly from side to side.
 
At 2 points in the channel on the 807 there are 2 drilled-out 'circles', and I assume that some kind of raised 'peg' which protrudes from the sliding 'block' clicks into these circles, such that the pre-set buttonhole stitch widths can be selected on the 807 (- which does not have the buttonholer dial of course). You can hear and feel the 'click' as the 'peg' clicks into each circle.

In between the circles the slider is flat, but the 'peg' or whatever it is, I assume (- I could be wrong though) must protrude such that the 'block' can nevertheless be held in place at whatever point on the flat channel you select (-by turning the stitch width dial), by the 'peg' pressing on to the slider channel's flat surface (?).

On the 840, although I can see a circle towards the top of the slider channel, (- the same as on the 807), there is no 'click', so I assume that there is some kind of problem with the 'peg'. Also since the knob bounces back to 1 when you turn it, I suspect the 'peg' does not touch the channel at all (?).

(I could be totally completely and utterly wrong here... :S)

2nd EDIT TO ADD: yes, after a rethink, I think I was totally wrong...  :|  :| :|

I'll see what more oil, heat, and patience will do.

Here's a pic of the parts I am taking about, with an arrow pointing to the slider channel, and another to what I assume is the 'peg'. The 3 other bits inside the circle make up the sliding block.

[edited because I got my words mixed up...]
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 15, 2017, 22:24:31 PM
Hi Madame,

That is quite a machine! Most industrial motors are 'Clutch' but these aren't very efficient and can have user quirks... like gradually accelerating without increasing pressure. The more recent approach is the servo motor, these are more efficient and have higher torque. And cost about £100,
Clutch motors can be had more cheaply because a lot of people are upgrading to servo motors.

If you're looking at industrial motors

Yes an industrial motor would be wonderful!!!
Are the servo ones the silent ones?
I used to work as a machinist on a flatbed industrial Brother many moons ago, and that was definitely a clutch motor.
Title: Re: Bernina Favorit 840
Post by: Roger on September 15, 2017, 22:59:50 PM
The servo motors are apparently silent, although I kinda like the tardis style hum of the clutch motor:)

Title: Re: Bernina Favorit 840
Post by: arrow on September 16, 2017, 01:09:46 AM
Ohh, rather random reply from me, but look at this (https://nb.shpock.com/i/U0Q8bzr6Aos2AAAR/).


(https://webimg.secondhandapp.com/w-i-m/Naehmaschine-Bernina-Favorit-840-Tisch.jpg)
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 16, 2017, 14:27:52 PM
Oh wow... is that a Horn cabinet?!
Title: Re: Bernina Favorit 840
Post by: Sewingsue on September 16, 2017, 15:17:59 PM
Looks like it. The one thing I do like about the newer cabinets is the clear plastic boxes on the inside of the door. Much easier to see what is in there.
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 16, 2017, 22:51:46 PM
Just a quick update - the 840 is looking quite shiny inside now, after a day of cleaning, oiling, more cleaning, wielding cotton buds and artists' brushes, and more oiling... I have also spent several hours gently scraping off old dried-out solidified grease from cams and shafts and things using wooden cocktail sticks... I found 2 tiny oil holes hidden next to the on-off fancy stitch selector ratchet mechanism thingy that were clogged with old grease, and after some careful prodding followed by drops of oil, the fancy stitch selector lever now works!   
0_0
... which means that the needle bar, which was erratically doing its own thing, now behaves as it should... 
8)

I can't see anything wrong with the buttonhole dial mechanisms, so all seems to be well there thankfully.

Unfortunately the stitch width knob is still not behaving, that kind of has me stumped. Not quite sure what to do about that, apart from more oil, heat, and wiggling. I have ordered some tri-flow penetrating oil from the US, which may take a while to arrive, but I have heard people say it is the best stuff for freeing up seized parts in vintage sewing machines.

I need to get hold of some grease at some point, as there are parts in there that need grease not oil. Is anyone able to recommend a suitable grease that I should use?? Thanks!

I shall post some photos soon  :D

[Edited because I was wrong about the grease... someone in the past must have applied the grease, and they were wrong to do it >:)]
Title: Re: Bernina Favorit 840
Post by: arrow on September 16, 2017, 23:28:46 PM
I don't think you should grease anything on this model, except from motor bearings. I would stick with oil if possible, you will get a smoother machine and it's easier to keep it clean in the long run. The reason for using oil is either because it's cumbersome to reach for regular applications (lids, screws, bottoms, etc, that needs to come off), or close to electronic/electric parts you can't afford the chance of a spill.

 If it's more practical to grease gears underneath or something like that, I like Finish Line Ceramic Grease, it can be found in bike stores, and there's similar stuff available in various brands, Triflow too. I like the slighly opaque - transparent greases with teflon in small tubes or tubs, not the gritty lithium stuff, spray can stuff (usually white) or heavier sticky greases. The current Singer grease is a synthetic transparent type, but there might be more than one type.

For the stitch width knob I'm not sure. Is it a simple turn knob in direct contact with the parts controlling the swing arm? I'm thinking it might not be complicated like the buttonholer and stitch selection knobs in the 800 series. I can feel there are other parts sliding and turning against the setting knob on my 900 Nova. Is it possible to observe, check and poke the parts involved in the back?
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 17, 2017, 00:04:52 AM
Thank you so much Arrow, I didn't know that.
The insides of this machine had been slathered in grease - it was everywhere, great big orange jelly-like chunks of the stuff, as well as dried-out crusty bits! Never mind, I daresay the grease may have helped prevent the insides from rusting over the many years the machine lay neglected and forgotten in a cold garage.

The stitch width knob operates by moving a sliding piece that moves up and down a channel in what I have learned is called the rocker lever. Here's a picture of the parts involved (I posted the same picture in my post yesterday).





Title: Re: Bernina Favorit 840
Post by: arrow on September 17, 2017, 00:26:24 AM
There's certainly room for parts sticking or needing tightening up  :S ; there's lots of them! How does the spring action work on it? Sometimes the parts that run up and down the rocker lever needs to have a certain resistance, or at least a part in relation to the lever-knob thing. I have always called this type of part a groove or channel too, the old Singers often have one behind the stitch length lever or turn-knob (my 99 and 201), but there are of course much less parts involved.
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 17, 2017, 13:33:04 PM
Here are a couple of photos which show the rocker lever etc.
There is a long spring which attaches to the rear of the stitch width knob, which pulls the knob back to the '0' setting.
(I have unhooked the end of this spring temporarily.)
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 17, 2017, 13:37:56 PM
There is no resistance in the motion of the part(s) that run up and down the channel in the rocker lever, they just glide up and down.
Title: Re: Bernina Favorit 840
Post by: arrow on September 17, 2017, 13:50:05 PM
Does the knob turn smoothly or does click in place along the way? I'm wondering what the spring is there for, what does the part it's attached to do?
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 17, 2017, 14:03:51 PM
The knob turns smoothly.
At no point does it feel as though anything is 'clicking' into place (in comparison, when I turn the knob on my 807 I feel 2 points where it 'clicks' - they are the buttonhole preset settings).
The long spring connects to a fixed anchor point beneath the fancy stitch selector plate.
The other end loops around a small peg at the rear of the stitch width knob; when the spring is attached it pulls the stitch width knob swiftly back to '0'.
Here's a photo:
Title: Re: Bernina Favorit 840
Post by: arrow on September 17, 2017, 14:19:42 PM
Is there a part that tightens up and make the knob stay in place? I can't make it out by the pictures. (The pictures act up on my side, doesn't always want to go to full size when I click them, but it's a technical issue sidetracking the subject). I'm thinking there might be away to detect if a part is sticky and interferes with the function, or a part is too loose. With all tiny parts it's a bit hard to see what job they are doing in the chain of things. I'm trying to look up how to take of the two part outer knob, they can be a bit tricky or even risky.
Title: Re: Bernina Favorit 840
Post by: arrow on September 17, 2017, 14:44:56 PM
The 840 looks mysteriously close to the 830 and 730, at least the upper parts under the hood.
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 17, 2017, 14:52:00 PM
Thanks for your help Arrow, I really appreciate it.
Regarding a part that may tighten the knob - I don't know at this stage.
I'm going to clean the underside of the machine next, and later this evening I'll have another look at the parts diagrams.
I am very hesitant about taking apart the knob, as it looks so complicated  :S

Here's a photo of the underside; I will look into image hosting later, then you should be able to view my photos more clearly I hope  :D

(Personally I love looking at photos of the insides of sewing machines.. :|...)

[Edit to add - the oil pan gasket was already damaged when I took the lid off, but the other piece is present and it was sealing well enough. Someone has worked on this machine in the past quite roughly; it looks as though the nylon stitch selector cam has been replaced, as the screws around there have had their 'slots' damaged. There are a lot of screws which have been damaged on this machine.]

Title: Re: Bernina Favorit 840
Post by: arrow on September 17, 2017, 15:07:40 PM
I'm always eager to take of lids and cover too lol, I guess that's one of the main reasons I fell into this in the first place. Some greases are reported to ruin plastic, luckily not all. I see the orangey mess you mentioned. I would stick to oil even for the gears under the bobbin area (dirty left side on the picture). If you are lucky, there's oil points reaching them from above, but if there isn't I guess this is the only part on the machine Berina recommended to grease. Oil on plastic gears are debateable, but from the info I have gathered so far, you are not doing anyting wrong by adding oil and tests show it lessens friction and wear even on plastic gears, including the better quality polyester materials. Finish Line Ceramic grease and Triflow grease are suppose to be safe on plastic gears.
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 17, 2017, 16:01:18 PM
Having read Fran's excellent 'Imgur' tutorial, I am going to try some hosted images:

Edit to add: good heavens, it worked! Hope you can see them ok now Arrow  8)

(https://i.imgur.com/vBt6bhEl.jpg)

(https://i.imgur.com/9JHxyUKl.jpg)

(https://i.imgur.com/fAgRY06l.jpg)

(https://i.imgur.com/jPoUuHPl.jpg)
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 18, 2017, 00:22:38 AM
Here are two more photos, one of the hook drive gears now the old grease has been cleaned out, and another of the thread guide, which sadly has not fared well.

(https://i.imgur.com/lhTjWbAl.jpg)

(https://i.imgur.com/n66dct8l.jpg)
Title: Re: Bernina Favorit 840
Post by: arrow on September 18, 2017, 00:48:46 AM
Surface rust usually comes off with further cleaning and polishing. Is the thread guide polished steel or chromed? It's best to have it off the body to polish it up, I don't know if replacements are available. Is it glued on? If it doesn't come off maybe carefully polish it with steel wool twined around a match or something like that.  An 840 is a very nice machine, once it was expensive and one of the best. I wonder why it fell in to disfavour and neglect? 10 years in a damp garage?
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 18, 2017, 02:12:16 AM
Surface rust usually comes off with further cleaning and polishing. Is the thread guide polished steel or chromed? It's best to have it off the body to polish it up, I don't know if replacements are available. Is it glued on? If it doesn't come off maybe carefully polish it with steel wool twined around a match or something like that.

My next task will be to remove the plastic rearside cover, and I'll find out a little more about the thread guide then.
Also I notice there is a small opening beneath the plastic rearside cover, and hopefully when I am able to look through it I may be able to see a little more of the stitch width knob mechanism.
I've been peering down into the knob mechanism with a torch... I can see something else move when I turn the knob, something behind the buttonholer dial... it's really complex inside there! I'm getting a bit obsessed with that stitch width knob  :| 

An 840 is a very nice machine, once it was expensive and one of the best. I wonder why it fell in to disfavour and neglect? 10 years in a damp garage?

Maybe it was because the stitch width knob didn't work, lol  :[
Title: Re: Bernina Favorit 840
Post by: arrow on September 18, 2017, 02:18:22 AM
A bit unfare though, it needed a service and repair. And all that grease, what a mucky job. It's probably been put through all kinds of misery and hardship. On the other hand it looks promising and like it will return to full function with a bit of tlc.
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 19, 2017, 18:10:16 PM
A bit unfare though, it needed a service and repair. And all that grease, what a mucky job. It's probably been put through all kinds of misery and hardship. On the other hand it looks promising and like it will return to full function with a bit of tlc.

Yes it is unfair and ever so sad what has happened to that machine - used and then discarded, and then forgotten, and left to rust.
But I am very happy that I found it, and it cost only £5!   :)

There are many tiny 'pimples' on the paint surface, and some of the paint has flaked off in parts, especially on the top lid, and more paint looks ready to flake off as well. The hand wheel is chipped and rusted too.
Arrow do you think I could touch up those parts with a few drops of suitable paint?

But yes I do believe that with time and effort and tlc it will indeed be up and running and sewing happily again!  :D
I am glad it still has its bobbin case and a bobbin; I looked on ebay and the bobbin case are very expensive. Also the needle plates, although scratched and rough in places, they are still present.
It is missing its knee-lever, but that is not an essential part really, just useful.

I've not yet removed the rearside plastic cover - the screws concerned, like so many of the screws on this machine, were locked solid, so I dabbed on some oil and shall leave them alone for now.
I am waiting for some TriFlow penetrating oil to to arrive from the US, but I'll keep dabbing oil on the stuck screws in the meantime as I don't want to force them.
There are many damaged screws on this machine, so I shall be patient as I do not wish to cause more harm.

Even though I cannot remove it yet, last night I gave the thread guide a very quick and cursory clean and it looks a little better. When I get the rearside cover off I will give it a better clean, and make sure the inner surface is smooth for the thread.

(https://i.imgur.com/WW7uZvIl.jpg)

I also removed the tension mechanism and cleaned out much lint and dust and also carefully removed some slight rust build-up on the inside surface of the cover; I didn't dismantle the rings and springs etc as it didn't seem necessary, they looked clean and were moving freely and had lots of 'spring'. I forgot to take a photo though.
There was some rust in the thread channel in the machine top lid - the ends of the thread channel are metal - so those had a gentle clean too.

I posted my stitch width issue on FB and a sewing tech from Australia commented saying that if the stitch width knob springs back to any position when it is turned, then it means the buttonhole mechanism is engaged. I'm hoping he will elaborate more on how to solve the issue.
I have spend so long gazing down into the mechanism with a torch I am getting quite obsessed about it... I am dreaming about stitch width knobs...!  8)

Tonight I hope to clean up the bobbin winding mechanism. The rubber is rather cracked, as you can see in the photo.

Here are some photos I took just now:

(https://i.imgur.com/NWE6riql.jpg)

(https://i.imgur.com/xCyM21el.jpg)

(https://i.imgur.com/zKA1zXVl.jpg)

(https://i.imgur.com/CzqV5eFl.jpg)

(https://i.imgur.com/FI8FFJll.jpg)

(https://i.imgur.com/Wi3U8T6l.jpg)
Title: Re: Bernina Favorit 840
Post by: arrow on September 19, 2017, 19:29:15 PM
I prefere touch up jobs on restration jobs like your 840. Is it the same light paint used on the 730s and 830s? It's a lighter white color on the 800 numbers, but much the same delicate paint, it scratches easily. Pfaffs have this type of paint, and the older Elnas. Touch ups and repair are well within reach if most of the paint is intact. I think you need to keep the original, because I don't think new decals or cut out stensils are avaiable? Everything can be done with enough time, effort and money, but it has to be withing reach and still give a nice result.

Paitning in missing spots requires the right type of paint, color match, and usually a bit of sanding down between layers. If you have a spray gun, or spray can paint available it will give the right result. Tiny scratches and needle punctures can be filled in with a fine brush. For smaller scratches there's clever toouch up products for cars that work for this type of paint.

Original Bernina Parts are always expensive, I don't know why. People insist the original bobbins and bobbin cases work better than the generic ones too, and tend to believe it. On a machine I know I will like and use I don't mind spending time and money on it, but not unnecessarily much. The Favorites are stronger and speedier than any of the others, unless you go for the even larger and heavier industrials.
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 20, 2017, 00:56:17 AM
There are 2 different shades of paint on my 840.
The top lid is painted the same light cream colour as my little 807, as is the machine body, while the hand wheel and the flatbed are a pale milky grey-green. I'm looking forward to doing some touch-up painting  :)

I didn't get any work done on the 840 this evening, too many chores that I have neglected since I took on this project caught up with me instead  :(

I have been thinking about the stitch width knob, actually I haven't stopped thinking about it, lol.
The last position on the buttonhole dial, position '5', which is the last position before it clicks back to vertical (and 'off'), has the needle set up to do a straight stitch in order to finish off the buttonhole.
I wonder if part of the buttonhole mechanism is 'locking' in some manner that corresponds to position '5', that is straight stitch, and is for some reason remaining activated and is being carried over to the buttonhole dial's vertical/'off' position.
Just a thought!
Off to turn in now, to dream of my stitch width knob...  |O   
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 20, 2017, 20:28:38 PM
I just found this strip of metal loose inside the machine - it was stuck to the inner surface of the base with old grease and goo...
The end which does not have the ridge looks like sheared metal, so it has snapped at that point.
As to whether it was once part of the machine mechanism - I'll see if I can see it in my parts list manual.

(https://i.imgur.com/BTVTe1Rl.jpg)

From the serial number I think the machine dates from 1980.
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 20, 2017, 23:20:12 PM
This appears to be the other end of the broken-off strip of metal:

(https://i.imgur.com/PxkjADAl.jpg)

(https://i.imgur.com/Dwm1VEDl.jpg)

It is part number 308.201.03.
Has anyone got a time machine so I can travel back to the 1980s and order one?!
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 21, 2017, 00:08:47 AM
I emailed Helen Howes, and she replied to my email with lightning fast speed (-as she usually does!) saying she hasn't got one, but will be in touch should she ever have a Bernina with that part in for breaking.

I'll ring Bambers in the morning and enquire there too.

I feel happy that I have (most likely) traced the root of the problem, but disheartened that as it is such an old machine, I may not be able to track down a replacement part.

Never mind, I shall continue doing what I can to fix up the machine, and live in hope of that part turning up  :)

If anyone knows of anywhere else I could try and source this part, please do let me know!  :)
Title: Re: Bernina Favorit 840
Post by: arrow on September 21, 2017, 01:02:51 AM
These challenges can seem impossible at first, but give it a chance, and if Bambers have been around for a while, there's a good chance. Don't forget the berninathirtysomething group on Yahoo, it's worth asking there too, not to forget ebay, anything can turn up there.

Come to think of it, that's the sort of part any metal tool shop should be able to make. I was once told the local school who teach metal work take on tasks like this as a good training, it depends on the teacher. A metal plate of suitable thickness, draw the shape, drill a hole, and the tools to hold it in place and saw out the piece, bend it in to correct shape. In 1980 the town was full of shops that did this, 1950 even more, there are still quite a few, but I need to go out of town.
Title: Re: Bernina Favorit 840
Post by: SkoutSews on September 21, 2017, 09:28:23 AM
Yes, that was my reaction too, Arrow.  It's just a little piece of metal.  If you take both bits into an engineering or metalwork workshop and give them the two pieces to use as a pattern, they should be able to make you a new bit.

Nonetheless probably easier to get one off a supplier or eBay if available.
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 22, 2017, 20:48:33 PM
I rang Bambers, and umpteen other sewing machine shops where they repair vintage machines and/or stock parts from donor vintage machines, but no-one at present has the part in stock.

I've hunted round for a local metalworker who would be willing to make me a cloned part, but sadly to no avail.

Earlier I decided to dust off my Dremel and have a go at making one myself - I did a short jewelry making course at college many many moons ago - as SkoutSews said, 'it's only a little piece of metal'!
The only bit I am not too sure about replicating is the ridged/crimped section visible along the part's length. Hmmm...

Then someone suggested that I use JB weld - which is something I had never heard of - so I did some research and apparently it is incredibly strong epoxy resin glue from the US.
I think if I cut out a strip of thin steel sheet metal and JB weld it to the underside of the broken part it might just do the job.

So I have ordered myself a packet of the stuff from Amazon... fingers crossed it should be here in a day or two, and I can get to work!
 8)

Here's a photo of the part, now that I have managed to remove the stuck screw and have got the other end out of the machine:

(https://i.imgur.com/BZvvLool.jpg)

Title: Re: Bernina Favorit 840
Post by: Roger on September 23, 2017, 00:07:18 AM
Have you tried Bogods?

https://www.bernina.com/en-GB/Footer-en-GB/Feedback-and-Service-Pages/Contact-us (https://www.bernina.com/en-GB/Footer-en-GB/Feedback-and-Service-Pages/Contact-us)

I've heard they're really helpful and well connected when it comes bernina accessories and parts, ancient and modern!
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 24, 2017, 12:50:36 PM
No news back from Bogods as yet, but I live in hope - Thanks Roger!  :)

I cleaned up the handwheel last night with some 000 grade wire wool. It was covered in hundreds of tiny spots of rust, and also larger patches on the rim. I am surprised and happy that all of the tiny spots have gone now leaving no trace. The bare metal I intend to touch up with some suitable paint.

(https://i.imgur.com/W95IEnHl.jpg)

The JB Weld arrived today  :)

But before making a permanent repair to the part I wanted to check first that the extra thickness on the underside of the part due to the repair would not cause the part to foul on any other mechanism.
So I cut a strip of thin, rigid plastic and sellotaped it to the underside of the part, to act as a temporary splint.

(https://i.imgur.com/NJc2IwLl.jpg)

^^ ...this is not the greatest repair in the world, this is just a tribute... 

I managed to wiggle the part in position and tighten the screw to hold it in place. There is free space beneath the part still, so I do not think the extra thickness would impede the part's correct functioning.

Now as I turn the stitch width knob I can hear a very satisfying 'whirring' sound, as tiny teeth on part of the knob mechanism graze against the little 'ridge' on the stem of the part.

Unfortunately however the stitch width knob still springs back to zero.....  :S  :S :S

I think the part, whatever its real name is, is meant to act as some kind of clutch or retarding mechanism, where on turning the stitch width knob the tiny teeth on the knob mechanism 'lock' on to the ridge on the part, thus holding the stitch width knob in position at the desired setting, counteracting the pulling force of the spring which would otherwise pull the knob back to zero.

I used quite a lot of oil though to free the knob and dial mechanisms when I first got the machine, as like everything else they were locked solid, and I suspect oil may be causing slippage and thus blocking any 'clutch' action. (At least I hope that's all the problem is).

So the next step is to clean the oil off... I think I have some meths somewhere... would meths damage plastic I wonder?

And I am fed up of calling it 'The Part', it needs a name!
[Edit: not a rude one though  ;)]
Title: Re: Bernina Favorit 840
Post by: toileandtrouble on September 24, 2017, 13:19:28 PM
It has that groove which is obviously meant to stop the wheel, why not call it the clutch?  (until someone in the know tells you better)  How brave of you to tackle it all.
Title: Re: Bernina Favorit 840
Post by: toileandtrouble on September 24, 2017, 15:07:05 PM
If you wanted a more personal name, and as it's the latest addition to the McCallit family, how about Wodger?
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 24, 2017, 15:18:05 PM
If you wanted a more personal name, and as it's the latest addition to the McCallit family, how about Wodger?

As in 'Wodger McCallit'?
Yep, the 'Wodger' it is then!
 0_0
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 24, 2017, 15:20:58 PM
Oh no, now my hyperactive mind has chucked out this:
https://www.youtube.com/watch?v=G7_oNBT9wsc
 :S

(edited for a better clip..)
Title: Re: Bernina Favorit 840
Post by: Madame Cholet on September 24, 2017, 17:10:37 PM
The saga continues...!

I had a peek at the teeth (- with a dental mirror, lol), and as you can see they are really very tiny, and much smaller than the ridge on the wodger:

(https://i.imgur.com/gUcmlVIl.jpg)

(https://i.imgur.com/zHrFHull.jpg)

I had to attach a safety line to the wodger as it was awkward to position into place and kept falling down into the machine innards; as you can see the ridge has been worn down somewhat on the front edge by movement of the teeth over the years:

(https://i.imgur.com/DNZ4uiMl.jpg)

I cleaned all around the stitch width dial mechanism with some methylated spirits, so that oil-related slippage ought no longer be an issue.

Unfortunately though when the wodger was replaced there was no change, and the stitch width dial sprung back to zero, again  ><

The next step is to cold weld a suitable metal splint to the underside of the wodger, and see what happens then.

The plastic I used as the temporary splint was not quite so rigid as the sheet steel I intend to make the permanent splint out of, so there would have been a very slight bend at the break, which may well have affected the grip of the teeth on the ridge.

Also the machine was so packed full of old grease and hardened oil that the notches between the tiny teeth may be clogged up; to clean them though I would have to dismantle the knob mechanism, which I didn't want to do, because it looks so complicated.

I also wonder if the wear on the ridge of the wodger is affecting its function, not to mention possible wear on the teeth, but I'll cold weld the wodger together first, screw it back on, see what happens, and take it from there.

Title: Re: Restoring a Bernina 840 Favorit
Post by: Barnyard on September 24, 2017, 19:50:52 PM
That's some dedication and determination you have trying to get this sorted and I applaud you for sticking at it. I will keep eyes open in my locale for donor parts as it would be fantastic to see it running. I do love a cheapo find, sometimes they do end up becoming a pain in the @ss and I pop them to one side and carry on with something else for a while.
Would I be correct in saying Bernina had part of their factory washed away in a flood and more specifically their spares warehouse? I could have imagined it but if true that would make vintage Bernina spares rarer than rocking horse poop.

I have just taken a Nova 900 into the workshop... Fingers crossed the problems are just the usual suspects!

Barny
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on September 24, 2017, 20:24:02 PM
Yes Barny I heard that too, about the flood, and the chucking away of all of the spares  :(

Tbh though I didn't even realise that Bernina supplied spares for such elderly machines; I contacted Bernina some years ago about a replacement motor inside cover for my little 807, and received a rather curt reply advising me that they do not provide spares for a machine so old...! So I got some Plastic Weld glue and made it (almost) as good as new  8)

Thanks for keeping an eye out for spares though, I am very grateful!  0_0

Best of luck with the Nova btw.
I have an instruction manual for the 900, and also a service procedure manual for 700/800/900 series machines, not paper but downloaded, if you need them.

Title: Re: Restoring a Bernina 840 Favorit
Post by: Barnyard on September 24, 2017, 21:16:55 PM
Madame, the service manual for the 900 would be really appreciated. I do have one, or did have one but right now it is not to hand and is probably 250 miles away in my other residence in South Wales. If you would be so kind, I would really appreciate the link. The 900 is a great machine but it does have it faults. Mainboard capacitor, carbon tracks in the foot control and a locking free motion that sticks like glue. Hmm... The better they get the more unreliable they get also.

Barny
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on September 24, 2017, 21:37:53 PM
I found the service manual today on the Vintage Bernina FB group, funny as I had not noticed it before!
It is my bedtime reading for tonight  8)
If you are not in that FB group (it is a closed group) and do not want to join then feel free to pm me an email address and I can email it if you would be happy with that  :)
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on October 04, 2017, 18:31:34 PM
Here's the latest installment of the continuing drama of my 840.

Well I set up the two bits of the wodger on some double sided sticky tape on a wooden block ready for cold welding with the epoxy glue, and cut out a splint from thin steel using a jeweller's saw; I had earlier taken a file to the smooth steel surfaces like the glue instructions advised. (Please excuse the cat hairs... I had a little helper just out of shot...  :meow:)

(https://i.imgur.com/69zvSRhl.jpg)

Then I mixed up some JB weld, put the bits in position, and left the glue to work its magic:

(https://i.imgur.com/pBjVCnul.jpg)

After 24 hours like the instructions advised, I fixed the now splinted and complete wodger in place in the machine.

Then I turned the stitch width knob.... and there was an almighty 'ping' sound, as the wodger snapped into two again, at the point of its original break...  :'( :'( :'(

(https://i.imgur.com/nKgBjrul.jpg)

The other half of the wodger has disappeared down inside the machine somewhere and I've not found it yet  :'(

Oh well never mind.
I think I'll try and make a wodger myself next and try that.
In the meantime though I think I'll put the 840 away for a while and do some sewing instead  0_0
Title: Re: Restoring a Bernina 840 Favorit
Post by: arrow on October 04, 2017, 18:48:25 PM
This is something my grandfather would make himself with out thinking much of it. We are just not used to make things our self any more; and I know I probably should get better at it. I don't mind bying replacement parts, but when we can find them a piece of metal, a vice and a file will get us far.

Unfortunate about the glue. I don't think there are very big differences when it comes to epoxy glues and super glue, which are of the best types to begin with. I have tried several brands, and it seems to be much the same stuff. Some materials glue better together than others. Maybe the surface area is too small to hold up when glued together. I have glued together a plastic accessory box, so far it holds up, but it is a weak point.

Title: Re: Restoring a Bernina 840 Favorit
Post by: Barnyard on October 04, 2017, 22:02:42 PM
Madame. Could you tell me the dimentions of the leaf spring? I may just have an idea. 99k bobbin plate leaf spring and the bobbin release finger both might be adaptable? I have both here as spares and I am happy to play but I will need pretty accurate measurements.

Barny
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on October 11, 2017, 11:16:03 AM
Madame. Could you tell me the dimentions of the leaf spring? I may just have an idea. 99k bobbin plate leaf spring and the bobbin release finger both might be adaptable? I have both here as spares and I am happy to play but I will need pretty accurate measurements.

Barny

Barny - Thank you  :)
The great news is that I have got hold of a spare one, and now my stitch width knob works as it should!

A battered and cord-and-pedal-less 1971 Bernina 830 found its way to me, so I took the leaf spring out of that.

It did not have the 'ridge', like the 840 leaf spring, it is just flat steel, but works wonderfully  :)
I wonder if the presence of the 'ridge' prompted the break in some way, like some kind of metal fatigue build-up each time the knob was turned back to zero...? hmmm...

Here's a pic of the 830:

(https://i.imgur.com/C75Xs8hl.jpg)

Someone in the past has got rather emotional about the motor cover and attacked it with a hammer by the looks of it. The broken bits of cover are missing and one of the under base fixing bolts and the thread it belonged to are also lost.
The brushes seem fine though and the motor itself turns freely.
The capacitor has blown, which probably prompted the assault on the motor cover, so the motor itself is most likely salvageable.

I bought the 830 for very little and intended to salvage it for parts, but I may decide to fix it instead at some point  -<

Here's a pic I made re. the leaf spring measurements - if I decide to fix up the 830 I will need another one...!
(Shaft width is 4mm).

(https://i.imgur.com/HC8gTVbl.jpg)

Now to get back to getting the 840 cleaned and painted and polished and back together, and, hopefully sewing...
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on November 09, 2017, 13:33:23 PM
This is just an update to say that the machine is back together now, everything turns freely, and the light works (hurrah!), but I need to disassemble the bobbin hook and race area as it is not making a stitch - I am getting thread tangles around the bobbin.

I want to strip down and clean around there but there are two tiny screws that hold the hook gib in position that have been badly chewed up by someone in the past trying to get them out. They are locked in solid so I don't know if that person was ever successful in removing them, which begs the question - besides the stitch width problem, was it an issue with the bobbin that eventually led to this machine being cast aside? Also the machine, when I got it, had a broken needle, which makes me wonder if there are broken bits of needle jammed in the bobbin mechanism somewhere I can't get at.

(https://i.imgur.com/F1mDfPBl.jpg)

The bobbin mechanism area wasn't touched in my initial deep clean of the machine because of the state of these frozen screws.
 
If I got them out the heads are so badly damaged that they may not go back in again. I could drill them out fairly easily but I need to source replacements first. I can't seem to find them in the parts manual, so I don't have parts numbers.

I'll get in touch with Bambers at some point, and ask, but I'll have another scan of the manual when I get chance to this evening to see if I can find them and their parts number.

I am hoping that they are some kind of standard Bernina screw that popped up in other machines, and not the Bernina equivalent of hens' teeth...  :\
Title: Re: Restoring a Bernina 840 Favorit
Post by: b15erk on November 09, 2017, 15:12:16 PM
Good luck with those screws MmeC.  I spent days trying to free a screw on the o/locker, and had to buy a special grippy plier thing.  After all that, and various parts, the dratted thing is still not sewing nicely......  :S

Your Bernina is too nice a machine to give up on though, as long as it's economical to fix it.  There's usually a reason that someone gets rid of a good machine.  My Bernina 730 needed a new motor after years in a damp garage, but it didn't cost me anything so it was worth it.

Good luck, look forward to hearing how you get on.

Jessie
Title: Re: Restoring a Bernina 840 Favorit
Post by: arrow on November 09, 2017, 15:34:55 PM
A lot of hand me dow machines sold or given away as faulty usually only needs cleaning, correct bobbin in stead of the wrong one (a supermatic), correct needle (in case of my  Phoenix), maybe a new motor belt. The 740 is a bit more advanced and sometimes they need a more thorough inspection and sorting out. It still sounds very promising Madame Cholet, being down to the last thing preventing it from stitching properly.
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on November 09, 2017, 17:05:17 PM
Great joy!!!!

SHE STITCHES!!!!!!!!!

 0_0 0_0 0_0 0_0 0_0 0_0

I went back to basics, and removed the needle plate and the feed dogs.
There is a fork-type part which fits below the needle plate, and which I had thought looked as though 'something' ought to slot into the gap in its 'fork'.
I had put the parts back together as I had first found them, following photographs I had taken on disassembly and originally, according to my photos, the gap in this fork space was clear.

So just now I removed the fork, and slotted the bobbin assembly 'finger' into the fork, and then screwed the fork securely into place.
I have put the feed dogs back and the needle plate, and the bobbin case and bobbin, and threaded her up, and .... she sews!!!
It makes sense now as the bobbin stays still while the hook turns around it. Without the 'finger' set into the fork space, the bobbin would not have remained stationary. So to greater minds than mine it would have been instantly obvious. Never mind, I worked it out in the end 
:)

B15erk and arrow - thank you for your helpful comments  :) :) :)
I am very glad I do not have to faff around with those screws!
And yes, one of my machines which I acquired for next to nothing was sold as not working...  turned out the problem was just a short piece of thread between the bobbin and the race, which took a couple of minutes to sort out, and now that machine sews beautifully  :)

The next step is to mount her in my treadle base... watch this space!

There is also some more painting to be done. I mixed up what looked a perfect match using 3 different pots of enamel paint. Then to my dismay the paint dried several shades darker than it was when it was wet  :'(
That was on the top of the machine, where much paint was missing; at least the rust is gone now and the bare metal is covered, even though the colour doesn't quite match.
The same happened with the handwheel too - it is darker in the places where the new paint was applied. But at least the handwheel is no longer covered in rust, lol!

At some point in the future I shall do some paint tests. I have the approximate recipe, it just needs to be slightly lighter. I intend to at some stage mix up a pot full, and then I will have it on hand for the 800 series Berninas that have found me over the years  :)

In the meantime the 840 looks less battle-scarred than she did when I got her, and she is sewing again, and that is what counts most I suppose  :)

I will post some pics later  8)
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on November 10, 2017, 17:52:14 PM
Well I sat the 840 in my treadle base, and realised that, because of the oil pan and hook drive gear housing beneath the flat bed being very close to its front edge, I would have to butcher the front wooden lift up flap thing on the treadle cabinet top in order to make the machine sit in the base properly...

... so instead I have attached a 90W generic motor onto the machine, sat it back in the original wooden base it came in, and the machine is running perfectly  :)

I originally intended to use this machine to sew medium-weight leather using a Bernina leather wheel foot, using it in a treadle base, and, (unlike my other vintage Berninas), with no expensive/irreplaceable Bernina motor at risk of blowing out.

But I'll run the machine with the generic motor for the time being at least. If that motor blows out it is no real issue as they are easily replaceable and not too expensive. I also have the option to run the 840 with a more powerful, industrial motor, but I'd need a cabinet or table for that, and at the moment I don't have the space.

I'm a bit disappointed at not being able to treadle the 840, but that does not detract from the fact that I am overjoyed that the sad, forgotten, rusty, seized-solid machine that sat in a garage for who knows how long and cost me £5, is sewing beautifully again!

 :vintage: :vintage: :vintage: <3

Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on November 10, 2017, 19:17:08 PM
The end panel on the 840 is plastic, so fitting the motor was, er, a bit of a bodge... note unsightly block of wood, lol  :|

But the motor is held securely in place, which is what counts I suppose  :)

(https://i.imgur.com/3cAKXzLl.jpg)


Here is the 840, back in its original wooden base, and ready to sew:

(https://i.imgur.com/AOIUyu3l.jpg)

There is still a little paint work needing to be done, but I'll get round to doing that eventually.
 <3 :vintage: <3

Title: Re: Restoring a Bernina 840 Favorit
Post by: Sewbee on November 10, 2017, 19:34:36 PM
It's a different machine!! I wish I knew how to restore old Berninas. I don't know what's under the hood, though. It's like my car - oil and window washer fluid are the only two places I know!  :[
Title: Re: Restoring a Bernina 840 Favorit
Post by: arrow on November 10, 2017, 21:37:31 PM
Congratulations Madame Cholet! I  have never seen a Bernina in a case like that, I don't think I seen an 840 at all, but not too long ago I had my hands on a 740. The 800 series has a bit more plastic than the 700 numbers in general, but I like the wood bit as a work around; it should hold up well in use. I hope you have two screws on the inside there too, if so it look perfect. The flatbed Berninas usually turns up in cabinets here, the freearms are of course on their own base plate. I don't think anyone should be afraid to take on a Bernina, they are a bit more advanced than straight stitchers but not impossible at all. You did a great job Madame Cholet, and it wasn't the easiest.
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on November 10, 2017, 21:56:23 PM
I hope you have two screws on the inside there too

Yes there are 2 screws holding the motor bracket to the wood, on the hidden side  :)

I really enjoyed the whole of the restoration process, I find it utterly relaxing, and I just drift off into my very private, alternative, so much happier, world.
 
And to be brutally honest, I prefer fixing up machines to sewing these days  :o

It helped that I had such wonderful support and help, from you and so many other lovely folk on this forum - thank you  <3

I do have one lingering concern though.
This is a photo of the hook drive gear housing, under the flatbed, with a plastic plug removed.
Do you think it is a grease port?
I know we decided that Berninas ought not be greased, but, arrow, what do you think?  -<

(https://i.imgur.com/5iE3l5ql.jpg)

Title: Re: Restoring a Bernina 840 Favorit
Post by: arrow on November 10, 2017, 22:20:44 PM
Did we ever track dow a user manual for the machine? I still lean towards oil, there isn't any electrical parts for it to interfere with and if you can apply a drop or two of oil now and then it will do at least as good a job as grease. I guess you have to unscrew the entire plate for a through clean up and inspection at least once a year or so anyway. Would grease or oil reach the parts that actually run against each other through the hole?
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on November 10, 2017, 22:49:09 PM
Yes I did find a user manual, and there is no reference to lubrication of the hook drive gear etc.
There is only one photo showing the oiling points beneath the upper lid, and another photo of how to slide off the needle plate so as to oil the shuttle area.

And yes - removal of that plug in the hook drive gear housing will enable oiling of the gears in there. So I think I'll just stick with using oil now and then  :)

The oil pan beneath the machine took a lot of oil, and thankfully the gasket, which was torn in one place, appears to be holding up. I was concerned I might have to replace it. But I know you can buy gasket material to re-make gaskets for vintage motorbikes, so I was not too worried. I am glad it is not leaking though.

I recently looked at a photo of the underside of the 850, which is the industrial machine. It looked the same as the underside of the 840, at least to my untrained eye.
Title: Re: Restoring a Bernina 840 Favorit
Post by: Roger on November 29, 2017, 20:33:46 PM
I’m so pleased for you that the hard work paid off! Nothing like seeing an old neglected machine produce a lovely stitch!
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on December 02, 2017, 18:48:41 PM
I’m so pleased for you that the hard work paid off! Nothing like seeing an old neglected machine produce a lovely stitch!

I have had a splendid time this past week or so playing with reconditioning the el cheapo spares/repair Bernina 830 (-with the trashed motor cover) further up the thread; it was the machine the leaf spring came from.

So far it has had a jolly good clean and some oil, I have cut out and fitted a rough and ready (but totally functional, hurrah!) leaf spring from plate steel, and I am currently rebuilding the motor cover using epoxy putty, a selection of glues, and a slice of wooden dowel...

I removed the blown suppressor from the motor, and then tested the motor, and the motor seems to be working just fine.

I shall post pics when all is done, so watch this space! 
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on January 29, 2018, 22:54:45 PM
I used the 840 Favorit lately to assemble the last bag I made - the monogram one from my bag thread in the Access All Accessories sub forum.
Although it managed to sew the leather ok, the feeble domestic motor I had fitted on it sounded as though it was in great pain and was grumbling dreadfully, and I had to turn the hand wheel by hand through the toughest bits. In order to sew leather it really needs much more oomph!
The ideal solution would be to sit the 840 in an industrial table with an industrial motor but at present I don't have the space for that.

However I was in Cornwall this last weekend and while I was down there I had a chat with a very nice chap called Alistair who puts together these DC sewing machine motors:
https://www.youtube.com/watch?v=u580rsg_9qU

He had been selling reconditioned vintage sewing machines fitted with the DC motors on ebay and also the DC motors on their own, but I had not seen any listed for a while and his ebay shop had gone rather quiet so I did wonder if he had stopped selling them.

Well like I said I managed to get hold of him and he explained he had just taken on a mobility business, and the mobility scooter side of things had pushed the sewing machine side of things into the background temporarily while he got his new business premises organised, but yes he does still produce the motors... phew!
He said if I emailed him pics of my sewing machine set up at some point then he would sort out a DC motor for me.
:)
Title: Re: Restoring a Bernina 840 Favorit
Post by: arrow on January 31, 2018, 21:49:36 PM
The motor looks very nice in the video, runs evenly and keeps it's power on lower speeds too. I have rarely had problems with the original motor on my 201, I have the standard motor on the 730 which is half or less of the amps on the Favorites. Your 840 should in theory have a strong, speedy motor? The old cast iron straight stitchers run faster and easier on less amps than a swing arm straight stitcher. I would double check specs on the new motor and compare with the one you have. I guess Alistair have found a good one, better than some of the YDK motors available (which isn't bad, just not much of an improvement, and they probably aren't all the same). Could be worth it of the Bernina motor can't be improved upon or just isn't up to the job.
Title: Re: Restoring a Bernina 840 Favorit
Post by: Madame Cholet on January 31, 2018, 23:11:11 PM
The motor looks very nice in the video, runs evenly and keeps it's power on lower speeds too. I have rarely had problems with the original motor on my 201, I have the standard motor on the 730 which is half or less of the amps on the Favorites. Your 840 should in theory have a strong, speedy motor? The old cast iron straight stitchers run faster and easier on less amps than a swing arm straight stitcher. I would double check specs on the new motor and compare with the one you have. I guess Alistair have found a good one, better than some of the YDK motors available (which isn't bad, just not much of an improvement, and they probably aren't all the same). Could be worth it of the Bernina motor can't be improved upon or just isn't up to the job.

Unfortunately my 840 came with no motor whatsoever, as it had been used in an industrial table with a clutch motor, which the seller kept to use with another machine head.

So I put the YDK motor on the 840 as I had it already, having bought it for another machine in the past but not used it. The 840 sews most fabrics amazingly fast with the YDK motor, but it really starts to struggle with thicker layers.

I want to use the 840 with my leather wheel presser foot to sew not-too-thick leather shoe uppers, and also to make some more bags. I think I am right in saying that Alistair has designed and assembles the DC motor set up himself, but he's a very busy man at the minute so I don't know when he'll have the chance to get one made for me, although he has promised that he will.

An industrial table and motor would be the ideal solution, but because of my lack of space I'm hoping the DC motor will provide the extra power I need, until I can afford to move to a bigger house, lol!