Can JB weld work on something like this?
 

So, I was humming along, cleaning and reassembling a 128, almost finished completely, just had to get the bobbin winder back together, and I could test sew it, then it happened.

The body of the winder fell apart in my hand! :shock:

Now I have to decide if I want to try to JB weld the piece that broke, or find one to buy online somewhere.

The only one I've seen is pretty rough compared to this one, but I think once there's JB weld on this one, it'll trump rough. *sigh*

DH says it will look bad, because it will have a blob of JB weld. Bad but working... worth it?
Can you even JB weld cast? (I'm new to this particular avenue of repair, does it show?)

I guess what I'm wondering / concerned about is the sheer strength of the JBW. It will have to be able to take pressure from the gear side, the tire side and the bobbin side.

Oh, I'm so sorry to see this. My dad was a welder and he called this, white metal..... really hard to 'weld'. But I'd think trying some JB weld would be worth it. If it doesn't work, you're no worse off.... have to find a new one at that point. I'd try it. Good luck.

nanna

Yes, you can JB Weld it. Clean it with denatured alcohol first then put the JB weld on and try to clamp it. Let it set for at least 24 hours then clean off the excess JB W and paint it with model paint or a Magic Marker.
How long it will hold is the question. Preparation of the broken places is critical. All oil, paint, dirt must be removed.

After that, hunt down one that's not broken.

Joe

Thanks nanna! I think I've also heard of it called pot metal? They really liked it for cars in the 80s.... maybe it's not the same thing, this machine is 1930ish (I knew at one time, but I've forgotten.)

I was so frustrated too, this machine has been handing me challenge after challenge. I might have yelled something not very nice when it happened too. :( A really tight for no (apparent) reason motor, all the wiring needing to be replaced, and that plate that goes over the knee controller is just in the wrong place to make working on the controller "easy". I worked on a 28, easily 25 years older later that day and had less trouble with it.

Oh good!! Thanks Joe! I take it denatured alcohol is different than the isopropyl alcohol in the bathroom?
Yeesh,... I will do what I can, but I'm not sure where I will be able to clamp. (Everything is rounded) I will be as creative as I can.

Hopefully it will last long enough that I can be a little more choosey. The one that I can find is older, probably from a 27, and missing a lot of paint, etc. That said, I'm ordering stuff from that guy for other machines, and it's less than $13, so maybe I should just suck it up?

You might just want to find a new bobbin winder on eBay...they are on there quite often. Usually around $15 or so. Try Joe's suggestion first, and if not satisfied or it breaks again, then get one.

I think some rubbing alcohols have a very high alcohol content but in general, yeah - denatured doesn't have the water/oil that rubbing alcohol usually has (and the alcohol itself is different but I don't know that that would make a difference in use.)

Clamping odd shapes is a challenge. I've had luck elsewhere (not sewing machine related) tacking boundary boards that will keep everything from shifting to a backing board on a backing board then wedging as tight as I can without the piece moving out of plane (i.e. buckling.)

You can hold it while JBing it with modeling clay. Also, drilling and pinning should hold it well. A machine shop can drill it for you. Either way it will cost about the same, except no shipping charges.

I've had luck clamping some odd shaped things using rubber bands, little velcro straps, and little bungee straps.

My 2 sons are into stockcar racing & one of them ran an engine for several races with a 4" crack in the side of the block that my hubby had patched with JB Weld. He says it takes about 24 hrs to cure though.

This stuff is 99% alcohol ... I always feel like there's a residue left when I use rubbing alcohol though. I wash my hands or whatever to remove it. I guess that wouldn't be good in this case, right? I will see about finding some denatured alcohol.

Thanks for the idea about tacking the pieces.

I think you're probably right. I guess it would be nice to keep it original, but JB weld isn't exactly original either.

The model clay wouldn't stick to the JBW? We have a drill press here, would that be sufficient?

Oh! I wonder if I could use our strap wrench to hold it. Thanks for the ideas!!

I would totally believe it. I run a motorcycle forum, and the things I've heard of them using JBW for is unreal. Years. Years they'll use things that have been welded.