Thread Tension Adjustments

[baileyuph]

Over time it has been noticed that the bobbin tension on one of my machines (111W155), tends to need adjustment (tightening).

Same thread, my suspect is the bobbin tension adjustment works loose.  Is this typical or time to get new parts and screws?

By resetting the tension, it does sew for a good while before noticing any change.  Maybe recording the position of the screw head (reference to a clock face) and try to determine if the screw is slowly turning. 

These synthetic threads are tough on a machine, maybe that is to be expected?

Is this a typical experience with the lower tension?

Doyle

[Mike8560]

Mine hAs stayed where I put it for the last 20 years.

[Darren Henry]

Same here, and I have operated at least 6 of them over the years. ( okay 2 were consew 225 & a 226, but same machine)

[lruthb]

You could try a little small drop of removable loctite on that screw then sew if your problem stops you know the screw is turning. This worked on one of the screws that holds my presser feet on.

[Mojo]

I was just talking to Bob Kovar from Toledo Machine the other day about general maintenance of machines.

There were two things he said needs cleaning over time. 1.) The tension spring on the bobbin case. It gets lint from the thread built up under it and will throw the tension off. 2.) The upper tension spring will get crud built up in it.

I took my upper tension spring apart the other day and cleaned the discs and got all kinds of crap out of it. There was alot of waxy stuff in there from the poly thread.

I am not saying that is what is wrong with yours, but worth looking at.

Chris

[bobbin]

I've noticed that some spools of the V-92/138 anti-wicking  thread we use in the shop "shed" more than others.  We have a spool right now that leaves the equivalent of fake "flocked" snow all over the machine head. 

Just before we closed for Christmas I gave 3 of the shop machines a "spa day" and they were divested of a lot of that waxy crud.  I did not disassemble the bobbin case tension though because the bottom tension has been fine, but I will give it a looky-see the next time I clean and oil them.

[Mojo]

I just got a new 1 lb spool of 138 and the waxy stuff is not near as bad as the last spool I had.

I have a spool of white 92 Poly that throws the waxy stuff everywhere. So much so I have to clean as I go.

I was having some tension problems a week ago and took my tension spring apart and cleaned the disc plates. I couldn't believe the amount of crap that was hidden down in there.

I typically take compressed air and blow everything out in the hook area as well as the tension spring area. The feed dogs also get cluttered with that waxy crap as well so I remove the needle plate and blow it clean with air.

Chris

[Gregg @ Keystone Sewing]

I was talking with Gregg from Keystone Sewing Machine recently (oh wait, that's me!).

He said to himself "Routine maintenance includes cleaning and oiling of the machine."  We like to use compressed air to blow out dirt, debris, and residue in the hook area.  Some threads and materials give off more or less residue, and can require more frequent cleaning.  It's best to keep the hook clean and well oiled, as this is the area of the machine that is going to be where we have most of our service issues when they show up.  As said, we can either remove the tension disks on the upper tension and tension spring on bobbin case.  Another way to clean is to release the thread tension, and blow air through them.  We can also run a piece of paper through the bobbin case spring to push out residue.  Or blow air through it, while gently opening the spring with a small flat head screw driver."

Hope some of these tips and tricks help!

[baileyuph]

Good points people;
The Consew 225/6 is essentially the same machine as the 155.

All threads are not the same, some leave different types and levels of residue.

Loc tite on the threads is a "right one" idea, especially on the older machines.

"Cleaning" and a little oil, as Bob Kovar (reported by Chris), Greg, and as Bobbin demonstrates at work is needed from time to time, depending on amount of use in keeping both tension devices working best.

So, what I have done is as advised, cleaned oiled, and reset the tension.  I recorded the setting crew position, relative to a clock face and will resume.  Most times it was a month or two or three, depending before I notice a change.  If tension changes and the screw position has not, then debris will be the immediate suspect.  If that doesn't do it, then replacing the spring and screws will most likely be the smart thing to do.

Thanks for the excellent input, I particularly appreciate the emphasis put on cleaning and maintenance that has been made.

Mike, if that machine works fine after 20 years maintenance free, don't dare touch anything.  It may never sew again.  ;D 

Doyle

[Gregg @ Keystone Sewing]

Loctite Thread locker 242 is a great product, but I've never recommend anybody to use it on their bobbin case tension adjusting screw.  They are split screws, and when made correctly, are 'body bound', meaning that you can back off the screw, without it vibrating or coming lose if not tightened down.  In fact, the bobbin case tension adjusting screw is not supposed to be locked down at all.  In some cases on some machines, the adjusting screw is held with a check screw.

[baileyuph]

[Loctite Thread locker 242 is a great product, but I've never recommend anybody to use it on their bobbin case tension adjusting screw/quote]




Greg:  I checked my tension adjustment screw and it doesn't feel like it is loose, actually I do not suspect it is the problem.  Possibly, it might have been a particle that got lodged under the spring.  So, I am cleaned and good to go with the sensitive eye on it.  The spring is not suspect, currently it is adjusted and holding a desired tension.

Any who, what are some uses for the 242?

Doyle

[Gregg @ Keystone Sewing]

Loctite Threadlocker 242 http://www.loctiteproducts.com/p/t_lkr_blue/technical-data/Loctite-Threadlocker-Blue-242.htm

This stuff is great.  It's used on the space shuttle.  It's mainly used where any type of vibration may loosen a threaded screw, usually small to medium thread sizes.  Best way to describe it is that it is like chewing gum wrapped around the threads.  Also, it's very unlikely to cause a problem, anywhere, so there is not harm in using it, even when not really necessary.  A small side note is that in some Pfaff owners books, they even provide a thread locking compound by part number.  No other mfg. does this I know of.

[Loctite Thread locker 242 is a great product, but I've never recommend anybody to use it on their bobbin case tension adjusting screw/quote]




Greg:  I checked my tension adjustment screw and it doesn't feel like it is loose, actually I do not suspect it is the problem.  Possibly, it might have been a particle that got lodged under the spring.  So, I am cleaned and good to go with the sensitive eye on it.  The spring is not suspect, currently it is adjusted and holding a desired tension.

Any who, what are some uses for the 242?

Doyle