Sewing Between 1 And 2 Layers Of 5 Oz - Cowboy 3200 Best Way?

[BDAZ]

Many of my designs require stitched two pieces of 5-6oz black drum dyed together and then jumping to a single layer for a decorative stitch then back to the two layers. I have never been able to get the bobbin thread on the single layer to pull down to the middle of the leather no matter how tight I make the bobbin nor how loose I make the thread tension. I occasionally will use a marker to touch up the thread so it looks ok or even use black in the bobbin when only the top is visible.

The image shows the transition between two and one layer with the tension readjusted to minimum.

Is 5-6 oz. too thin for the 3200? I am using natural poly 207 top and bottom with a 24 needle.

Any suggestions?

Thanks!

Bob

Edited December 6, 2014 by BDAZ

[Northmount]

Do a test with a number 23 and a 25 needle and see if either makes a difference. Chart I use recommends a 25 for 207 thread, which would make it easier to pull the thread up, which would mean reducing the top tension even further. 23 would make it harder to pull the thread up so would require more top tension. As to whether one or the other might work, only a test will prove it.

Tom

[BDAZ]

I have finished my first batch of product so I can do some testing tomorrow. At this point I'll try anything but there is a noticeable difference on the tension between the bobbin and needle when I loosen it for the single layer. Any looser and the springs will fly off..

Thanks!

Cya!

Bob

[dirtclod]

Set the tension for the 5 ounce piece and it should sew fine on the thicker part my machine does anyway.

Edited December 7, 2014 by dirtclod

[BDAZ]

I can't get it to sew the 5 oz. What you see is as good as it gets. Bob even sent me a lighter spring for the upper tension but it didn't make much difference. I initially thought this machine was not capable of sewing a single 5 oz layer.

Thanks!

Bob

[BDAZ]

I tried the 25 and it made no difference, also played around with the tension with just marginal improvement. The knots are still visible from the top but they are below the surface.

Thanks!

Bob

[Colt W Knight]

I have this same problem with my machine on thin leather.

[silverwingit]

Bummer. My Cobra Class 4 doesn't have this problem so I cannot advise you. Sorry

Michelle

[Northmount]

Where you have to decrease the top tension to just about nothing, try increasing the bottom tension so you have more range to play with.

Tom

[BDAZ]

I quote from my initial posting:

"I have never been able to get the bobbin thread on the single layer to pull down to the middle of the leather no matter how tight I make the bobbin"

Thanks!

Bob

[Northmount]

Take the bobbin basket out and examine it for any stuck pieces of thread, or other type of damage that prevents increasing the bobbin tension. Sounds like something must be holding the spring open somehow, or bent. I'm not using the same machine as you are, but increasing my bobbin tension makes a huge difference (requires more) in the top tension required to pull the bobbin thread up. It sounds like you have little bobbin tension.

Tom

[BDAZ]

There seems to be plenty of tension on the bobbin and this has been like this since new. I have the bobbin tension cranked all the way down. I have removed the bobbin basket to clean it and check for any thread, dirt etc, but all is good. Sews perfectly with two pieces of 5-6oz but not one. The machine is advertised as a "Heavy Duty" leather machine...

Cya!

Bob

[Colt W Knight]

I was thinking when I talked to Neel about this machine, he was saying 5-6 ounce is the lower limit of the machine.

[silverwingit]

Um, er, I wasn't going to say anything for fear of seeming to gloat. I decided to go ahead and chime in again in an effort to give you hope that further investigation might bear fruit.

I have no trouble sewing two thicknesses of very thin deer hide on my Cobra 4. It doesn't matter which thread and I do not have to adjust tension when switching to different size treads.

Maybe a different shuttle or new tension discs or even different thread/needle combinations? I'd hate to see you give up.

Michelle

[BDAZ]

I think Colt may be right. Colt what machine did you purchase?

I hope Bob Kovar chimes in tomorrow, but it was never an issue and the machine does an outstanding job on all the heavier sewing I usually do. This order is unusual because I usually make this item with a lining and then there's no issue, but the customer wants these unlined. This is a repeat order and the customer is happy but I would like to come up with a solution. This is my best customer and his business is worth thousands so I'm not going to give up.

I was able to alter the electronics so I have the perfect rage of speed. I'm sure there must be a tweak or hack to make this work.

Thanks!

Bob

[TwinOaks]

I don't know your sewing machine experience, so please don't get offended if you already knew this: On your bobbin tension - there are TWO screws that need to be addressed. One is the tension, the other is the locking screw. The locking screw HAS to be loosened to adjust the Bobbin tension screw, then retightened. If you didn't do that, it's likely that the range of adjustment wasn't fully exploited.

[Colt W Knight]

I have a really old Consew 206. I was all set to order a 4500 and a I had to spend my sewing machine money on some emergency stuff.

Edited December 8, 2014 by Colt W Knight

[BDAZ]

Thanks Twin Oaks. I am aware of the set screw and do loosen it to make adjustments. The tension screwe is locked down all the way. There is quite a bit of tension on the bobbin, and measurably less than on the needle.

Thanks!

Bob

[Northmount]

I wonder if a new tension spring would make any difference?

Tom

[BDAZ]

Toledo sent me a lighter tension spring and that helped. As I said, the tension on the needle is noticeably less than on the bobbin which is maxed out. The machine sews flawlessly on thicker leathers but not on 5-6 oz.

I think there is some inherent tension in the thread path that limits the machine to thicker leathers.

Cya!

Bob

Edited December 8, 2014 by BDAZ

[BDAZ]

I Spoke to Bob Kovar this morning and he suggested using a lighter thread. I switched to 138 with similar results. I suspect that stitching a single piece of 5 oz. leather doesn't have enough grip to keep the knot centered in the middle. I assume with 2 pieces of thin leather there may be some more resistance to pulling the bobbin thread up. I will try two pieces of 3 oz and see what that looks like, though that's not something I would usually stitch.

So to summarize, I'm pretty much where I started.

Thanks for all the input. I wonder if anyone with a heavy leather machine can successfully stitch a single layer of 5 oz with 207 thread?

Cya!

Bob

[pcox]

After reading your post I went to my 3200. 5 oz. natural strap, #23 needle, 207 bonded nylon thread top and bottom. Bobbin tension screw all the way tight, now here is what made it work, top thread thru only 1 hole on spool pin, top tension spring taken off a domestic sewing machine 6 coils of .040 wire, top nut 1/2 way on, bottom tension flush with stud.

[BDAZ]

Thanks! I just completed 25 items and the leather used ranged from 3-4 oz to 6 oz. I replaced the upper spring with a spring from a bicycle hub quick release, much lighter, and I lightened up on the foot tension. The single layer 6 oz (drum dyed veg tan) was perfect. No knots visible from either top or bottom and the transition to 2 layers of 6 oz is perfect.

The items that have a single layer of 3/4 oz look a bit like your pics. The knot is visible if you look for it but below the surface, though not in the middle.

All my work is drying from wet forming but I'll post some pics tomorrow. How do you have the center foot height set?

Cya!

Bob

Edited December 13, 2014 by BDAZ

[pcox]

As far as the center foot height if you are talking about the slot on the back it is in the center of the slot. The pictures show the knot much worse than looking at them for real. I just put the black in to see the white better no white on top but 2 or3 black dots on the single thickness back

[BDAZ]

The center foot seems to be adjustable with the two set screws or should it be all the way up? i haven't messed with it but does seem to be a possible parameter to play with.

I have never had visible knots on the back..guess your top is a little too loose.

Thanks!

Bob