Melonie Report post Posted April 20, 2017 Today I switched from my usual #138 thread to #92. I changed out the needle and triple checked my threading but for some reason the bottom thread keeps coming up. I've adjusted the top tension both ways but I can't seem to get it right. Any suggestions?? Quote Share this post Link to post Share on other sites
chasman52 Report post Posted April 21, 2017 Try adjusting the bobbin tension. The smaller 92 will may slip past the settings that you've always used for the larger 138 thread Quote Share this post Link to post Share on other sites
bushpilotmexico Report post Posted April 21, 2017 Does thread make a difference? 90% of my sewing with my Cobra 4 is using black or brown 277/207 bonded nylon. When I switch to white 277/207 that I bought from the Leather Factory the bobbin thread comes to the top. I can decrease top tension and increase bobbin tension but no luck. I can then replace white with brown 277/207 and it sews perfectly. Quote Share this post Link to post Share on other sites
LumpenDoodle2 Report post Posted April 21, 2017 5 hours ago, bushpilotmexico said: Does thread make a difference? 90% of my sewing with my Cobra 4 is using black or brown 277/207 bonded nylon. When I switch to white 277/207 that I bought from the Leather Factory the bobbin thread comes to the top. I can decrease top tension and increase bobbin tension but no luck. I can then replace white with brown 277/207 and it sews perfectly. It does sometimes seem to make a difference. I have 2 reels of thread, bought at the same time, both are marked the same, but one of them always needs a bit fiddling with the tension to get it right, The only obvious difference are the colours. Quote Share this post Link to post Share on other sites
Big Sioux Saddlery Report post Posted April 21, 2017 11 hours ago, bushpilotmexico said: Does thread make a difference? 90% of my sewing with my Cobra 4 is using black or brown 277/207 bonded nylon. When I switch to white 277/207 that I bought from the Leather Factory the bobbin thread comes to the top. I can decrease top tension and increase bobbin tension but no luck. I can then replace white with brown 277/207 and it sews perfectly. Definitely makes a difference. One supplier's 277 is NOT necessarily the same size as another's 277. I am currently using 2 spools of white 277 from different suppliers. One is noticeably thicker than the other. Both are from reputable suppliers, but I can't run the lighter weight 277 on the top side of my Cowboy 4500, so I use it for winding bobbins. It doesn't cause an issue there. Even the same brand but different colors does make a difference. In my experience it's the colored threads that are more likely to cause issues, white being the least likely. Brown seems to be the worst out of the three colors I use: white, black, brown. Quote Share this post Link to post Share on other sites
Melonie Report post Posted April 21, 2017 7 hours ago, LumpenDoodle2 said: It does sometimes seem to make a difference. I have 2 reels of thread, bought at the same time, both are marked the same, but one of them always needs a bit fiddling with the tension to get it right, The only obvious difference are the colours. Yes, the new thread I'm trying was bought at the same time, same suppliers and brand, but this one is a cream color and obviously a different size. My other one was brown. Quote Share this post Link to post Share on other sites
Wizcrafts Report post Posted May 7, 2017 If we lived in the quilters' world we could use the thread tension scales made for that market. I see this device in my Wawak catalog and advertised by Superior Threads. But, it is designed to take the bobbins used in domestic machines, not most leather machines, generally speaking. If such a device was made available to users of 441 and 205 type machines, we could more easily set the bobbin tension whenever we changed bobbin thread. With a fixed bobbin tension, all one would have to do is tweak the top tension for different sizes of top thread. As it is, we must adjust both the top and bottom when changing spools, colors, sizes and brands of thread, in order to keep the knots centered betwixt the layers. As has been mentioned, when you change from a larger diameter to a smaller diameter thread, on top or in the bobbin, the existing tensions are bound to decrease, but not always equally. The top tension is also affected by the amount of tension in the thread guides, the check spring, and the lower roller on the 441 and 205 machines (and some others). Furthermore, the replacement bobbins for the 441 and 205 machines are not always precision made, in my experience. Some of them are longer or shorter than others. Shorter is no problem as they remain inside the end of the case where the bobbin spring alone sets the tension on the thread. But longer bobbins protrude from the end of the bobbin case and can press against the frame of the shuttle, increasing the tension on the thread beyond what you set on the spring tension screw. This happens on my Cowboy CB4500 and on my Singer 31-15, both of which have horizontal axis bobbins on the left end of the machine. I don't notice this problem on the vertical axis, top loading bobbins in my Singer walking foot machines. Oh, by the way, black bonded thread is often double dyed, which sometimes results in it coming off the spool like a coil spring. This increases the thread tension and can even cause twisty knots and thread being thrown out of the tensioners to happen at the worst of times. Quote Share this post Link to post Share on other sites
Sonydaze Report post Posted May 8, 2017 22 hours ago, Wizcrafts said: If we lived in the quilters' world we could use the thread tension scales made for that market. I see this device in my Wawak catalog and advertised by Superior Threads. But, it is designed to take the bobbins used in domestic machines, not most leather machines, generally speaking. If such a device was made available to users of 441 and 205 type machines, we could more easily set the bobbin tension whenever we changed bobbin thread. With a fixed bobbin tension, all one would have to do is tweak the top tension for different sizes of top thread. As it is, we must adjust both the top and bottom when changing spools, colors, sizes and brands of thread, in order to keep the knots centered betwixt the layers. Thanks, you just gave me an idea.. I think I still have a trigger gauge for gunsmithing. It measures pull from an ounce to several pounds. It should be easy to measure thread tension with it. Quote Share this post Link to post Share on other sites
chasman52 Report post Posted May 9, 2017 3 hours ago, Sonydaze said: Thanks, you just gave me an idea.. I think I still have a trigger gauge for gunsmithing. It measures pull from an ounce to several pounds. It should be easy to measure thread tension with it. Please let us know if that works, because I like guns, and all the stuff that goes with them. So, for me it is a good reason for a new toy Quote Share this post Link to post Share on other sites
OLDNSLOW Report post Posted May 9, 2017 yup me to so please let us know! Quote Share this post Link to post Share on other sites
