Singer sewing machine sticky pedal

[paulsherwin]

If you are in serious doubt about the pedal's health, and particularly if it contains asbestos, I would replace it. There's nothing wrong with that - it's exactly what a sewing machine mechanic would have done in the 70s as a 'service upgrade'. It becomes part of the machine's long history.

[David G4EBT]

Originally Posted by DianeDavies

Hi

The capacitor buzzed out ok but he does have a spare if needed.

I wouldn't be content to leave that in situ. For a suppression capacitor across the mains (as in your foot-pedal speed controller), it should be a self-healing flame-retardant Class X type specifically intended for that purpose - not for example, a mains rated polyester capacitor.

EG, this sort of thing:

https://www.rapidonline.com/kemet-r4...acitor-10-2694

Quote:

"A 0.1µF 310V 15mm pitch metallised polypropylene film capacitor with excellent self-healing properties. Typical applications include interference suppression and across the line use. 100% screening factory test at 2,200 VDC/1,500 VAC"

End quote.

Hope that might help.

[DianeDavies]

Hi Merlinmaxwell, what do you recommend for cleaning the discs? ethanol? de-ionised water? canned air? Air dry or paper tissue? None of the above?

[paulsherwin]

Ethanol / isopropinol (IPA) is always a good bet. Good old meths also works well.

[DianeDavies]

thanks for all the other contributions, spotted the asbestos washers, no worries, know how to handle this beast! My brother and I rolled asbestos into balls and blew them across mum's ironing board whence the asbestos came. Half a century later not yet a problem. But don't let your grandkids to do that! Looking at capacitor replacement, thanks for the link. And Paul, Mum had lots of attachments, so going to do our own Sewing Bee some day!

[DianeDavies]

OK we have IPA, ethanol 95% and meths so going to smell fantastic in the work area!

[Spencervs]

Just out of curiousity, how do you get the discs out? I couldn't seem to find a way to do that but I have heard that people do.

[PaulR]

Originally Posted by DianeDavies

And Paul, Mum had lots of attachments, so going to do our own Sewing Bee some day!

I have just seen one that will sew on buttons. I wonder how they manage that

[DianeDavies]

I don't think I have a photo of the actual disc extraction, but we plan to re-open to clean them so I'll try and get one. Once we got the brass contacts out and tipped it forward there was no stopping them! More care needed next time!

[DianeDavies]

Hi We went back in to clean the discs, there's about 60 per side, so it took a while. On one side all were intact, but one had an arc like a partial eclipse missing, the second side had the same, but worse the bottom disc which is thicker was completely in pieces. It can't be repaired or reinstated, but it will make the stack shorter. Is this an issue? should we just get on and rebuild?

[DianeDavies]

I have photos of the actual disc extraction, but need to re-size to post here.

[Cobaltblue]

Hi Diane have you tried posting your pictures?

The Forum software usually resizes automatically without too much drama.

Be aware that if your using an Apple device (such as an iPhone) the pictures may come out upside down.

Cheers

Mike T

[DianeDavies]

Yes got the photos, blow by blow, from opening the "white ceramic housing for the carbon discs" If it has a special name I can't give it!
As before the discs shot out of the tubes with no effort but there was some loose dust inside which was wiped out with an alcohol dampened Kim wipe, a lint free tissue. Each disc was carefully cleaned by my husband, using the same method, all 120 approx.... Slid back in except for the shattered one, all re-assembled and machine ran afterwards, although I think it's smoother in acceleration he thinks its still more on-off than gradual. There was no interference from the old capacitor but we will order one, in case we can't get an electronic foot pedal. photos 1-5 , attached; 6-7 to follow

[DianeDavies]

And the last two photos...of the dust in the tube and how easy it was to slide the carbon discs back in the housing.

[paulsherwin]

I don't think removing one or two discs will have much of a negative impact, but it may mean that the machine starts rather abruptly when you press the pedal gently. It will do no harm to try it though, and you might be lucky.

I do think you are right to consider fitting a modern thyristor pedal if you plan to actually use the machine in anger. They do give much better control, especially as the load on the motor changes.

The Singer 66/99/201 derived models will last forever if you maintain them properly - no nasty plastic gears in there! I'm impressed that you're persevering.

I am with Paul on the few missing disks, it won't matter. What could matter is the squeeze before the contacts connect, that will give a sudden start, and too fine a start may arc the disks, juggling springs to mind.

[DianeDavies]

Firstly we already have the sudden start, but secondly no arcing apparently! We want to use it in anger as it should cope well with denim!

[paulsherwin]

It will cope with denim and even thin leather, but the motor belt will need to be in good condition and correctly adjusted. New neoprene belts only cost a pound or two if needed.

An electronic pedal is particularly desirable if sewing heavy material.

[factory]

Originally Posted by David G4EBT

I wouldn't be content to leave that in situ. For a suppression capacitor across the mains (as in your foot-pedal speed controller), it should be a self-healing flame-retardant Class X type specifically intended for that purpose - not for example, a mains rated polyester capacitor.

EG, this sort of thing:

https://www.rapidonline.com/kemet-r4...acitor-10-2694

Quote:

"A 0.1µF 310V 15mm pitch metallised polypropylene film capacitor with excellent self-healing properties. Typical applications include interference suppression and across the line use. 100% screening factory test at 2,200 VDC/1,500 VAC"

End quote.

Hope that might help.

The capacitor in these are actually fitted across the switch contacts, the typical failure mode is it goes short circuit, which results in the motor running all the time. That is what happened with this one I was asked to fix a few years ago, the old cap was a Dubilier 0.1uF at 250V, it got replaced with a modern X2 capacitor (edit: the same one as pictured in the Rapid link).


David

[DianeDavies]

Absolutely nothing to do with my sticky pedal but while looking for a replacement I spotted this! "Quality-Leather-Treadle-Machine-Cowhide Belt." Now there's a thought for the keen restorer of vintage sewing machines! We've had a treadle machine rusting in the back garden for 30+ years. All the wooden parts have fallen off. Do I or any one have the energy?