Problem With Stitches On My Cylinder Arm Machine..

[CustomDoug]

Hi I haven't used my cylinder arm machine much to sew anything other than chrome apparel leather. But just yesterday I was sewing some veg tanned leather while putting together a bible cover. While sewing the two layers together, the rounded edges gave me problems.... specifically the stitches from the bobbin side tends to want to 'walk' off the edge of the leather (just barely stuck into the edge) while the top stitch is right where I'm trying to put it - which is about 1/8" from the edge. I was using a #18 leather needle with #92 nylon thread. Maybe the needle is too small for the thicker leather and causing deflection possibly? I'm using a spring loaded 1/8" compensation foot to help maintain my distance from the edge (letting the spring loaded part just hang off the edge of the leather) and going fairly slowly, especially around the edges. Also, I used HD double side tape to hold the two pieces together before starting the stitch run. Any tips for eliminating the bobbin stitch's wandering ways? Thanks.

Doug C

[Northmount]

Same sort of thing happened to me. Have to keep the object you are sewing flat, perpendicular to the needle. If you lift the left edge, stitching on the back moves closer to the edge. I built a flat table adapter, problem gone.

Tom

[CustomDoug]

I should have known. Yea supporting the piece is always a bit of a headache with the cylinder arm machine, unless it's a tubular item. I've thought about making an adapter but kept thinking I'd get myself another flat bed machine soon. I guess I need to break down and make the extension though. Any tips on making one, what did your construction consist of, laminated top and edges?

Doug C

[Northmount]

Doug - Took me a while to find it!

Sorry, that thread was locked. Here is a pic.

Tom

Edited September 15, 2014 by northmount
error in post

[Troy Burch]

Says I don't have permission to view it. Why not?

[Itch]

As mentioned above.. It took me awhile to keep the work flat on our 441 machines..It will fool you.

[CustomDoug]

Thanks for the picture Tom, that really does help. I think I can make one now.

[Darren Brosowski]

Would be using a 20g needle with #92 for a start

If the machine uses a 794 needle then it is a long thin needle for the job.22g or lower I would be using a machine with 135X16 needle.

[Gump]

This problem can also be caused by the feed dog not being high enough when the needle begins to penetrate the leather, allowing the leather to be pushed down by the upper foot , thus bending the edge of the leather down. It can also be caused by too large of a hole in the feed dog, allowing the leather to be pushed down into the slot in the feed dog. The slots in the feed dog can get worn to the point that it is too wide to support the edge of the leather. Check to see if the feed dog is pushing up on your work just as the needle/upper foot start to push down. Both feet and the needle should touch the leather at the same time, holding the work even and flat. Gump

[CustomDoug]

.. It can also be caused by too large of a hole in the feed dog, allowing the leather to be pushed down into the slot in the feed dog. The slots in the feed dog can get worn to the point that it is too wide to support the edge of the leather. .. Gump

This might be a "BINGO !" moment... the feed dog on this machine looks worn the heck out for sure. I will switch it out, been meaning to address that at some point just for aesthetics if nothing else - thanks for the heads up Gump.

The machine is a Consew 287R and uses 135x16 needles.. but I'll install a #20 needle too, thanks Darren.

Doug C

[CustomDoug]

OK, I'm still having this problem.. it's soo frustrating. I changed out the old feed dog and needle plate for new ones. I am also now using a flat table top attachment.

Using #23 needle/ 207 thread / 4-5oz leather (2 layers at the corners) / spring loaded "compensating" foot (to help keep a 1/8" or so distance from the edge). I'm usually only having problems at the apex of the rounded corners - which I slowly walk the needle around one hole at a time. Threads look GREAT on the top side after I've sewn completely around the piece but when I flip it over I'm occasionally getting threads walking off the edge of the under side leather.

Here's one thing that I'm thinking may be the problem - I've gotten into a habit of just using the very strong double sided leather basting tape, it works great for my garment leathers (which is what I've mostly sewn up until lately) and is quicker and a lot less hassle than contact cement. I bast the two pieces together with the tape and hammer around the edge on both sides. The two layers are even at that point and all feels solid. You guys think this tape could be the problem? Will the contact cement solidify the two layers better, not allowing them to shift apart (because it seems like that's what's happening to a slight degree)?

Doug C

[truenorth]

Just my opinion,, if you let glue dry well most things, or in my case nothing moves!!!I like using double sided tape too but items gets "shifty" glue takes longer and is messier but works better if dried the needle doesnt stick and bring up the material just my 2 cents, hold on we got rid of our pennies up here lol!

[Constabulary]

Maybe you can post some pictures of your work. I think some member might know what the problem is when they see what happend. Pictures are often telling more than 1000 words.

[Tramps Leatherworking]

Is this a walking foot machine?

How much tension do you have on your presser feet?

On some machines I have actually had to lift and lower the presser feet after each stitch on sharp corners to keep the machine from distorting the bottom layer...

[CustomDoug]

Yes, it's a walking foot machine, cylinder arm w/ a flat table top attachment.

Tension at Presser Foot : I think (IIRC) I adjusted the presser foot to have more pressure a couple years back when I started sewing garments, to help me sew over multiple layers of garment leather where several seams meet. I just have sort of left it at that setting (been sewing garments until lately) and never touch it. Should I back that adjustment off then, to help this walking off the edge situation ? BTW - is this normally done on the fly then moved back to a lighter tension after the thick seam area? Or generally set and left?

Glue : Which glue would you guys use - contact cement or tanners bond (PVA white glue) ? I have both.

Foot/Guide Choice : Which kind of presser foot and/or edge guide would you guys recommend for going around fairly sharp rounded corners? Like I mentioned I'm using a spring loaded 'compensating' foot because it's great at keeping me a constant distance from the edge ON THE STRAIGHTS (no other edge guide needed)... but perhaps it's spring loaded "blade" is doing too much pushing down at the apex of the round corners. I have been slowly walking the needle around the corners . I am manually lifting the presser foot to see where the needle will go, and like I said it does look nice on the top side when done.

Sewing rounded corners advice : The nature of sewing tight rounded corners can be more difficult than it seams.. because I find that you never really take the leather item to the edge guide at the apex of the turn. If I go too deep into the turn, the corner will come out too squared off. I'm thinking that's where my foot might be messing me up - pushing the leather down there. Any advice for sewing tight rounded corners? Thanks so much guys..

Doug C

Edited November 6, 2014 by CustomDoug

[Northmount]

Remember that if you lift the presser foot too high, you release your top tension. So the bobbin thread will lie flat on the bottom.

Tom