kgg

If you go the digital servo motor route get a get a good one. They are not all equal. The most important thing to remember is the more coils it has the better like the Reliable Sewquiet 6000sm 12 coil or the Sailrite 12 coil version. The main caution is if you plan on adding a speed reducer and a needle positioner to the mix make sure the digital servo motor you planning on purchasing will work properly with those items. Not all do when coupled with a speed reducer. Personally, l like to keep my setups as simple as possible, servo motor, belt, machine. The more electronic controls you add into the setup the more stuff can go wrong. My rule of thumb is if I need better speed control, I may think about adding a speed reducer but if I need the addition torque that a speed reducer will provide then I need a bigger/ better/ different class of sewing machine. Just my thoughts, kgg

I agree the needle is inserted and threaded wrong. kgg

I don't really think the Campbell Randall falls within the "doesn't take to much space" category of machines. It probably weights in at north of 150 lb. kgg

This is a sad lost, my condolences to his family and friends. He will be missed. kgg

That sound and that ever so light jiggle of the main pressor foot remains me of when I had to shim the lifter arm that connects the chain to the foot pedal out from the sewing machines body by about a 1.5 mm at the pivot bolt in my clone. kgg

Try the following link, Chapter 15 Height of Feed Dog and Chapter 16 Adjusting the walking foot and presser foot. https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjZ-N-O3cbvAhW8GVkFHX8VDjEQFjAAegQIBRAD&url=http%3A%2F%2Fwww.juki.co.jp%2Findustrial_j%2Fdownload_j%2Fmanual_j%2Fdsc240%2Fmenu%2Fdsc246%2C-7%2Fpdf%2Finstruction_eg.pdf&usg=AOvVaw3QW7CAPsYD4bN-kd6LF8GW kgg

Yes, please do as it may help others down the road that may experience a similar problem in the future. kgg

As listed in their menu "Leatherwork sewing machine" These are just a their portable LS model painted green instead of the rust brown with a maximum thread size of V92. However they did table mounted them on a nice compact table and coupled it with a nice servo motor on it. They use to be marketed through Tandy. These portable sewing machines were intended for repairing sail canvas. Keeping presser foot / feed dog marks/indentations from you leather is going to be difficult. I think for what you want to sew, you would be disappointed with the performance / ability. If you are really dead set on that type of machine an alternative is the Reliable Barracuda and at about $500 US. You could then buy a servo motor and build a small table to sit it in. I agree and disagree with UWE on the the Juki 1508 or its clones. I found that with my Juki 1541S which is down from the 1508 capability wise that if I was doing thick stuff it was great. When it came to thinner stuff I had to spend to much time in dumbing it down and then reverse the process to do thick stuff again. So to do thin stuff I bought a Juki 1181N, that machine covers off the thinner stuff and leaves the 1541S to do what it was good at. The 1508 will do your sheaths and more but on wallets I think it would be over kill. I would agree with Uwe buying as local as possible and being able to test drive a machine is invaluable. kgg

Another thought. Some of your stitch length problems may also be your feed dog, inner presser foot and your main presser foot. If I am not mistake on the Techsew 2750 all three are slick smooth. That couple with smooth material they may not be providing enough grip to properly feed the leather though properly which may contribute to a shorter stitch length. kgg

Make upload the video to youtube and give a link. First off, I would send the video onto Techsew and ask for their advice, guidance, etc. Another option would be to download a Juki LS-341 or 1341 manual as it would give you idea as to how the linkages for the needle and inner pressor foot work. kgg

My concern with spending that kind of money would be who you are purchasing it from. Is it someone that is using the machine or a dealer or a re-seller or a flipper. If it was from a dealer maybe worthwhile in making an offer, if it suits your needs, but from a flipper I would need to see it running and gone through. I would also investigate the availability of parts / accessories and check with dealers for other used machines. kgg

Normal ones are for blocking sunlight to help keep the room cooler while others are for security. Do a google search for "Hideaway Helper classroom security blinds". kgg

With such a new machine I also wonder why and am going to assume with such a new machine it was done with instructions / guidance from Techsew. I also agree, It is excellent advice. I would also contact Techsew by phone and or email. Outlining the problems you have been having with the machine as well as email them photo's / video. The more information the better. kgg

Very Nice. kgg

I agree using a domestic sewing machine is going to be difficult to say the least or near impossible. If you don't have access to a proper fur sewing machine you are going to need at least an industrial walking foot sewing machine and even then it may prove to be difficult depending on the machine and your sewing technique. kgg

Buy the best basic machine you can afford. If that is a new or used machine buy a brand name. When you go to sell the machine a brand name will be easier to sell, sell faster and command a better price. Don't be penny wise and pound foolish. Buy Once, Cry Once. kgg

Thank you for the photo's on the thread path. What I see: i) In the first photo you are missing the felt pad that holes the thread against the back part of the squareish guide just before the thread goes down to the needle guide. Lost of tension at that location of top thread. ii) This is I think your main problem. You say you are using a "125 size 20 135 x 17 DP x17 " the needle needs to be a #23 needle for V138 or if the material is sticky or tough you need a #24 needle. The needle hole is just to small to pull the top back up with the additional V138 bobbin thread so it lays flat. The #20 needle is good for V92 thread. As a note the easiest way to make sure the top thread is seated as far down in between the main tension disc's as possible is to have the needle up to it's highest point away from the feed dog and then rise the pressor foot up and lock it by using the pressor foot lever at the rear of the machine so the tension discs release from each other then thread top thread through. Sometimes the thread may look like it is between the discs but isn't seated right in the middle of them. kgg

The Kobe LS-1341you have is a clone of the older Juki LS-341. I have a couple of questions that may narrow down the problem. 1) What size of thread are you using for the top and in the bobbin. It appears to be V138 or V207 for the top thread. I am going to assume it is V207 on top and V138 in the bobbin as the bobbin thread appears to be smaller. For V207 thread the minimum needle needs to be a 135x17 #24 needle in fabric or 135x16 #24 in leather. But you may have to move up to a #25 needle in sticky or thick stuff, which your machine is not rated to accommodate. If the needle doesn't make a large enough hole to haul the top thread and up back up you can get the straight bobbin line. 2) Top tension and thread path. If possible could you post a detail photo('s) from the top of the spool to the eye of the needle. 3) Bobbin tension not properly set. Have you done the bobbin drop test? Your machine is only rated for V138 in the bobbin. 4) Presser foot tension may need to adjusted slightly. As a note I run V138 top and in the bobbin in my Kobe LS-1341 most of the time. kgg

This particular machine is setup with a clutch motor for a start that I could easily replace with a servo motor, has a small bobbin, parts are expensive, always hated the color (which has no affect as to it abilities), V92 max thread machine, has always been too fussy for my liking in comparison to the Juki's / Singer's that I have owned and is getting a little long in the tooth. Some of it maybe me but I prefer not to use it as I have other machines that give me a lot more. Just my experience with this machine. kgg

I have attached a Pfaff 1245 subclass pdf which maybe of some help. I also have a Instruction Manual for old casting Pfaff 1245 but it is to large to insert as it is 8MB so if you want it I could email to you. Your machine looks very similar to mine but a newer version as mine is the awful puke yellow color. My Pfaff 1245 is delegated to the dark corners of the basement still in working order. Parts can be expensive in comparison to other machines. Like everything some people love them, some not so much. kgg Pfaff 1245 Subclass Old Casting.pdf

For me I have never felt that I needed to add a speed reducer. I find the plain jane brush type servo motors give me all the speed control that I so far have needed. Like Wiz I still have a couple clutch motor setups for when I need to punish myself. The problem or potential problem when a speed reducer is coupled with a high torque motor as that arrangement has the potential of over torquing the machine head parts. Having to much available motor power and the additional available torque provided by the speed reducer can be worst (twisted parts, unwanted trips of safety clutch, etc.) then an under sized servo motor. The best thing would be to ask the advice of the supplier of your machine for their recommendations as to the proper sizing of both the servo motor and speed reducer. kgg

Another couple of considerations to adding a speed reducer which will depend on the style you choose. Sometimes adding a speed reducer involves cutting the belt slot longer to allow for the new belt angle and location. You are probably going to have to drill additional holes through the table top to mount the speed reducer and sometimes depending on where the K-legs are mounted you may have to relocate the the whole top further to the left, just depends on who mounted the table top to the support K-legs. Even though the 1541 has a front mounted bobbin winder should yours fail you may find it cheaper / easier to just add a belt driven winder which may or may not be able be done if the belt slot has been lengthen. For some not being able to tilt the machine back easily is of no real concern for me it is a major concern as I tilt my flatbeds back all the time to change the bobbin as my fingers are to fat to fit comfortably underneath to remove/ install a bobbin properly. kgg

Nice work, remains me of the old lead shot bean bags we used to hold down engineering drawings but yours is an awful lot nicer. kgg

My reasoning is that in comparison the 1541 is an excellent commercial grade machine weighing in at 80 lbs (head weight), the 1508 is an excellent industrial grade machine weighting in at just over 98 lbs (head weight) and 2810 is an excellent professional grade machine weighing in at just over 123 lbs (head weight). My experience is the heavier the machine head, in a class, the longer it will last. My suggestion is based on the 2810 being properly maintained and properly rebuilt. If you can't go and physically check the machine out ask for very detailed photo's of not only the exterior but the thread guides, hook assembly, top and bottom of machine showing shafts and timing. Best of luck, kgg

For the number of hours of use per day you are planning on using the machine I would probably go for the 2810 over the 1541. kgg