Ferdco Super Bull, Juki 441, or Artisan 4000

[esantoro]

Those of you who use the Ferdco Super Bull, Juki 441, or Artisan 4000, What's the minumum leather thickness you run in the machine?

from time to time, I'm trying to use 207 poly thread/ 180 needle to sew a decorative stitch on a bag strap made of one layer of 4/5 oz veg tanned (sometimes with a 2 oz suede backing). The stitch doesn't lay down smoothly. I don't have this problem if I'm using two layers of 4/5 oz veg tan, just with one layer.

The obvious problem seems to be thread tension, but I think I've correctly tried all the variables related to tension. I'm wondering if I'm expecting my Super Bull to do something it wasn't intended for. The only thing I haven't tried is to do the same stitch with 138 poly/ 160 needle, the smallest rated for the Super Bull. I have a feeling this will work fine, but I don't really want to use a smaller thread on the straps than I use on the rest of the bag. I will try it anyway just to settle the problem once and for all.

Thanks for your help,

Ed

Edited April 9, 2007 by esantoro

[Art]

Hi Ed,

Thread is too big, needle is too big. If you want to stick with 207, you should lay down a stitch crease and then stitch in that. Also, please post a picture of any problem you have. Does "doesn't lay down smoothly" mean it lays on top of the leather, or something else, is it not tight enough? Sometimes you will have to up the bobbin tension on thin leather to pull the lock down further or really back off the top tension which can give you a loose stitch. They will tell you it will sew a dollar bill to doubled saddle skirting without adjustment and most times it is true, however the stitch will not pass my quality criteria, just marketing. The more out of the design range of a machine you get, the more adjustment you will have to make, then you have to back that out when you go back to your "normal" work. Hence, a lot of us have more than one machine.

Art

Those of you who use the Ferdco Super Bull, Juki 441, or Artisan 4000, What's the minumum leather thickness you run in the machine?

from time to time, I'm trying to use 207 poly thread/ 180 needle to sew a decorative stitch on a bag strap made of one layer of 4/5 oz veg tanned (sometimes with a 2 oz suede backing). The stitch doesn't lay down smoothly. I don't have this problem if I'm using two layers of 4/5 oz veg tan, just with one layer.

The obvious problem seems to be thread tension, but I think I've correctly tried all the variables related to tension. I'm wondering if I'm expecting my Super Bull to do something it wasn't intended for. The only thing I haven't tried is to do the same stitch with 138 poly/ 160 needle, the smallest rated for the Super Bull. I have a feeling this will work fine, but I don't really want to use a smaller thread on the straps than I use on the rest of the bag. I will try it anyway just to settle the problem once and for all.

Thanks for your help,

Ed

[esantoro]

Hi Ed,

Thread is too big, needle is too big. If you want to stick with 207, you should lay down a stitch crease and then stitch in that. Also, please post a picture of any problem you have. Does "doesn't lay down smoothly" mean it lays on top of the leather, or something else, is it not tight enough? Sometimes you will have to up the bobbin tension on thin leather to pull the lock down further or really back off the top tension which can give you a loose stitch. They will tell you it will sew a dollar bill to doubled saddle skirting without adjustment and most times it is true, however the stitch will not pass my quality criteria, just marketing. The more out of the design range of a machine you get, the more adjustment you will have to make, then you have to back that out when you go back to your "normal" work. Hence, a lot of us have more than one machine.

Art

Art,

Thanks for this reply and all your replies. They are extremely educational.

I think I need to tighten the bobbin tension for the thin leather (the straps wouldn't look right with a lower guage thread), which seems to go against a certain logic. I thought I'd have to tighten tension for thicker leather. Anyway I was told that I would very rarely have to mess with bobbin tension, just the two top tension controls.

I backed off the top tension and got exactly what you have written: loose top thread, that isn't "laid down smoothly" and the needle penetrates the thread on subsequent stitches.

I've been listening too much to that marketing blurp you've mentioned: "it will sew a dollar bill to doubled saddle skirting without adjustment," and felt that I shouldn't have to adjust the bobbin tension.

I've been under the impression, perhaps mistakenly, that once I start adjusting the bobbin tension, it will be difficult to regulate tension consistently. How much of a turn of the bobbin tension screw is enough for noticeable change? full turn? half turn? Is there a method to use to check appropriate tension, or is it just something one can feel and sense over time?

I'd like to experimnt but want to be sure that I can return the bobbin tension to its original setting, which works for 80 percent of my needs. For now I'll just remember how many turns of the screw I make clockwse, so I can reverse it later.

At any rate, adjusting bobbin tension is something I should start getting more familiar with, so I might as well jump in .

Thanks so much again, Art, for your help.

Ed

[Art]

Hi Ed,

The top tension pulls the "lock" up into the leather and correspondingly the bobbin tension pulls the lock down. There is of course a balance between the two and the strength and stretch of the thread. Now most of the time the factory settings will cover a wide range, but not always, thread and needle sizes add to or detract from the friction (and hence tension) on the whole system. When making bobbin tension adjustments, a quarter or half turn is all that should be required so go lightly here. Also check the way you have your bobbin threaded, I have seen totally backwards upside down bobbins run with heavy top tension on thick leather fairly well, but with light thread and low tension this could be a problem, however it doesn't sound like you have too much bobbin tension. Just check everything.

Once you get the tension right for the thinner leather, you may be able to go back to thick leather with just a top tension adjustment to pull the lock up a bit. This would be your new "factory" setting.

Art

Art,

Thanks for this reply and all your replies. They are extremely educational.

I think I need to tighten the bobbin tension for the thin leather (the straps wouldn't look right with a lower guage thread), which seems to go against a certain logic. I thought I'd have to tighten tension for thicker leather. Anyway I was told that I would very rarely have to mess with bobbin tension, just the two top tension controls.

I backed off the top tension and got exactly what you have written: loose top thread, that isn't "laid down smoothly" and the needle penetrates the thread on subsequent stitches.

I've been listening too much to that marketing blurp you've mentioned: "it will sew a dollar bill to doubled saddle skirting without adjustment," and felt that I shouldn't have to adjust the bobbin tension.

I've been under the impression, perhaps mistakenly, that once I start adjusting the bobbin tension, it will be difficult to regulate tension consistently. How much of a turn of the bobbin tension screw is enough for noticeable change? full turn? half turn? Is there a method to use to check appropriate tension, or is it just something one can feel and sense over time?

I'd like to experimnt but want to be sure that I can return the bobbin tension to its original setting, which works for 80 percent of my needs. For now I'll just remember how many turns of the screw I make clockwse, so I can reverse it later.

At any rate, adjusting bobbin tension is something I should start getting more familiar with, so I might as well jump in .

Thanks so much again, Art, for your help.

Ed

[esantoro]

Hi Ed,

The top tension pulls the "lock" up into the leather and correspondingly the bobbin tension pulls the lock down. There is of course a balance between the two and the strength and stretch of the thread. Now most of the time the factory settings will cover a wide range, but not always, thread and needle sizes add to or detract from the friction (and hence tension) on the whole system. When making bobbin tension adjustments, a quarter or half turn is all that should be required so go lightly here. Also check the way you have your bobbin threaded, I have seen totally backwards upside down bobbins run with heavy top tension on thick leather fairly well, but with light thread and low tension this could be a problem, however it doesn't sound like you have too much bobbin tension. Just check everything.

Once you get the tension right for the thinner leather, you may be able to go back to thick leather with just a top tension adjustment to pull the lock up a bit. This would be your new "factory" setting.

Art

I'll check my manual, but I've never paid attention to whether the bobbin is inserted a certain way. Should the thread come off clockwise or counter clockwise?

Ed

[Art]

Pretty sure bobbin spins clockwise when paying out thread, it should NOT make a 180 degree turn into the bobbin thread tension spring but should feed straight in smoothly.

Art

I'll check my manual, but I've never paid attention to whether the bobbin is inserted a certain way. Should the thread come off clockwise or counter clockwise?

Ed