sandmanred

I got the 2 stitch cam printed today. It works just fine

Here is a design for a cam for a Bernina that does a 3 stitch zigzag and a 2 stitch zigzag. I've printed and tested the 3 stitch version and it works great. The images show it took me several tries to get the design right, the cam installed on the machine and the last one shows the face of the cam that should face the operator when installed on the machine. I'm not sure of the polymer it's printed of. The two stitch version has not been tested yet. 2 point cam v2.stl 3 point zigzag cam 6 lobe v2.stl

I can also put the file in another location but can you point me to the section you think is best?

The stitching on my cam happens at 4 difference radii measured from the center of the cam, from smallest to largest they are 27.8, 28.5, 29.3 and 30.0 mm. This range drive the needle through the full 6mm of zigzag travel. How much larger did you go? I think my machine could go even wider as the first thing the needle hits is the slot in the presser foot. I'll look into getting one at Global.

So I bought a stack of cams from a Bernina 830 in hopes of happening upon a 3 stitch zig-3 stitch zag cam in the stack. Closest I got was a serpentine zigzag with about 9 stitches in a repeat. So used the cams to engineer a cam to do the 3 stitch zig-3 stitch zag. It took me a couple of tries but I got it. Lucky to have a neighbor with a 3D printer to test the design. Here's a picture of the results of the first and second try, the 3 stitch zigzag and the serpentine cam from the 830 along with a video link. And a copy of the .stl file in case you want to print one for yourself. 3 point zigzag cam 6 lobe v2.stl

Thanks for the information!

Maybe picking up a dead thread but I too just picked up a Chandler 217 with the cam box but only one cam. I'd really like to find the 3 and or 4 point zig-zag cams if anybody knows of a source?

Goldstar provided bobbins that fit

Tried amazon for bobbins the ad called out the correct part number but they weren't even close. I'm waiting on an order from Goldstar. In the meantime I added a larger handwheel pulley that when combined with my servo with a small drive pulley gets me down to just over a stitch a second and low speed.

So far, so good. Thanks for the threading advice. I got it with one bobbin. So far I've ordered 2 different types that claim to fit a Pfaff 138 but so far none of them fit. They are all too wide bye at least 1 mm. Where is a reliable source for bobbins that fit? I need part Pfaff 9033 or 91-009033-05.

I'd check your hook for burrs and also check hook the timing but I'd suspect something on the hook is abrading the top thread. It gets pretty thick there and the tension it takes to pull the top thread down will increase with the thickness

Great, thanks! I got as a head only. It was seized due to being stored outside. Luckily the only thing seized was the hook spindle. All it took was some penetrating oil and some light tapping to free is up. Timing was close, the hook would kiss the needle when the needle was in the far right zig-zag position. A little adjustment and that was taken care of. One question about thread up, again the on line manuals I can find are hard to read. I think the photo shows pretty clearly what I did and it does seem to work but it'd be good to know the intended thread up. The video shows #20 needle with T90 thread going through 4 layers of vinyl coated canvas. This machine will definitely handle heavier needles than advertised. https://youtu.be/QyTlOcVOwdc

I know this is not a great leather machine but this is by far the best website for help on sewing machines. I got this one as a loose head. It does sew as is but is clearly missing a few parts. Looking for advice on what the essential missing parts are. It seems to have two tension discs sets. Not sure the thread up when you have them both. On line manuals I can find are printed so poorly I can't make out the thread up. It seems to sew okay with the one tension stack but it shouldn't be too hard to find the parts to refurbish the missing one. It also looks like I at least need a thread guide at the bottom of the needle bar. There are other missing guides but they don't look too essential? I think B in the model means it's the more heavy duty model. Not sure what the S means Any other advice for this machine is welcome.

Please post a photo of the bottom of your presser foot, I'll explain why. Here's my story and theory about what may be happening. I had a similar presser foot to the one in your video. I could get nice balanced stitches. But then when I'd change to another foot like a roller foot or zipper foot I had to back way off on the top tension. And then take the tension back up when I switched the foot back into the machine. I determined that with the foot like yours and going forward as the stitches get pinched between the presser and the needle plate and thus requiring higher tension than say a roller foot or zipper foot. In your case when you go in reverse the stitch just made is not under the presser foot so the tension set for going forward is now way to high for going in reverse. Here's a picture of what I did to resolve my problem. I filed a small relief in the bottom of the the foot like yours so that the stitch being formed doesn't get pinned to the needle plate by the foot. Now I can switch feet with no tension adjustments. I think this same relief could solve your problem.

I missed your point, got it now. If you can get plate of the same thickness it shouldn't be too hard to cut the outside to shape. Then you could drill the corners of the cut out for the feed dog and use a jewelers saw to cut the waste away and clean up the corners with a file.