kgg

I don't hand sew but I would think maybe leather gloves something similar to those used for Cycling, Weight Lifting or Wheelchair use would work. kgg

Yes and No. The manuals do show how to wind a bobbin, load/unload a bobbin, what direction the bobbin should turn when the bobbin thread is pulled and what screw to adjust for increasing or decreasing the tension just not how not how to get the tension close to what is needed for a given thread size or what not to do when adjusting the tension screw. Note: 1) Juki LS-1341 can have it's bobbin tension adjust while in your hand and not in the machine and you can do a drop test like a flatbed machine since it is a split case setup. 2) The manuals indicate the bobbin should turn clockwise NOT counter clockwise. Here are three examples from the Juki manuals. Other Brand Name and Clone machines may differ. : i) Juki LS-1341 (compound walking foot cylinder bed)--> threading a bobbin ii) Juki LS-1341 (compound walking foot cylinder bed) --> adjusting bobbin tension iii) Juki DNU-1541S (compound walking foot flatbed)--> threading a bobbin iv) Juki DNU-1541S (compound walking foot flatbed) --> adjusting bobbin tension v) Juki DU-1181N (walking foot flatbed) --> threading a bobbin vi) Juki DU-1181N (walking foot flatbed) --> adjusting bobbin tension kgg

The bobbin is the same it's the bobbin case that is different. Here is a good video on doing a drop test on a flatbed machine. The same applies for a Juki compliant bobbin case on a cylinder arm. kgg

This a typical location for the "tilt stump". Typically just made of plastic, pressure fitted into a hole drilled into the table top and meant as a temporary rest. The machine " slithered off the table hinge and into the drip pan " indicates to me incorrect / damaged hinge and or hinge installation. I have never had a head slip off and with my stubby fingers I am also titling my flatbed machines back to install / remove bobbins. kgg

Downside I think is getting the bobbin tension adjusted. The Juki style is where the bobbin is placed in the top half part of the bobbin assembly, threaded and tension adjusted while still in your hand and then dropped in place. Personally I like being able to adjust the bobbin tension this way as I can do a bobbin tension drop test. kgg

That is correct for the Cobra Class 26 it does not have a Juki compliant bobbin assembly. Here is a video for the bobbin installation. kgg

My two cents worth: Notes i) The recommended size of needle for Tex135 (V138) is a 140 (#22) thin material, 160 (#23) medium material and 180 (#24) thick material. ii) Your 130 needle is really meant for Tex90 (V92). A good reference chart is ( https://www.tolindsewmach.com/thread-chart.html ). iii) V45 has a breaking strength of 7.5 lbs iv) V69 has a breaking strength of 11 lbs v) V92 has a breaking strength of 14.5 lbs vi) V138 has a breaking strength of 22 lbs If I'm not mistaken the 269 is cylinder arm and by adding a simple table top attachment you would have sorta kinda a flatbed for versatility. Personally I wouldn't bother changing the thread size and do all the sewing with Tex135 (V138). kgg

Yes, I have purchased bobbins and bobbin cases for a Sailrite clone. I purchased them from CKPSMS brand and they were decent quality. I have also bought from Aliexpress. kgg

I guess "reasonably priced" is a relative thing. Each needle at $28.57 AUD ($26.23 CAD) and I thought paying $4.50 CAD for 794S size 250 was expensive. kgg

The simple answer is it will not be suitable for leather work. This is a drop feed machine made for sewing fabric at high speeds. kgg

I'm glad you had good success with the dealer. Seems strange, you should contact them or Alder directly for a solution. Ah, you should bought a Juki. kgg

My take: i) Lower startup speed is determined by the amount of bottom end torque it was designed for and how good the electronic closed speed loop controller. Even if you can change the startup parameter to something less then 500 rpm the motor you will introduce some annoying things like stalling, surges and poorer rpm regulation. ii) The cheaper servo motors have 6 internal coils while the better ones have 12 coils which will typically provide better lower startup speed that is more consistent and smoother not just because of the added coils but chances are of they will have better electronic controls. I could not find any information on that particular servo motor but it would be a safer bet to assume it has 6 internal coils or call / email the manufacturer. iii) The only way of getting a reliable slower, smoother startup speed with the brushless servo motors is to install a speed reducer or buy a better servo motor. Getting the 1 stitch per second is probably equal to about 60 RPM. This I think is a bit unrealistic. If you really need that low a speed you would have to build an 8.33 to 1 speed reducer and probably change the servo motors shaft pulley. Keep in mind that an off the shelf speed reducer is 3 to 1 which will give you about 166 rpm. iv) to properly determine a realistic sewing speed you would need to do a pulley calculation knowing the size of the sewing machines handwheel and the size of the servo motors pulley based on the minimum startup speed. kgg

This wouldn't have been my first choice of a machine mainly due to the hole it would punch through the material, 2.5mm diameter unless you are sewing items above 1/2"(12.5mm) in thickness or saddles. I would have probably gone with a Juki LS-1341 or clone with a speed reducer as it would use a smaller diameter needle the system 135 x 16 x needle size for leather. My understanding is the 969 is a class 441 machine that takes the system 7x 3, 794 or 1000 needles (Schmetz). There are needles available for 7x3 or 794 from #19-#27 (120-220) for V92 to V415 thread. I would talk to the dealer to track down the needles if you are going to keep the machine and maybe discuss exchanging the machine for something like a 869 which would take the system 135 x 16 needles . kgg

That is very true there are situations where you just can't get the bobbin thread. Nice tip for machines without reverse. kgg

Thank you Everything in moderation. The aim is two fold. Even tension and to prevent any excess bobbin thread on the underside of the leather or fabric that would cause a problem. kgg