kgg

Another thing to check is the history of the machine. Was this a one owner hobbyist machine, how long has that person owned the machine, why are they selling it and was it a machine that was used in a factory environment at some point. I am wary of machines, no matter of what brand they are, that have been used in a factory type setting as they are usually run hard, put away wet and disposed of when about to require repairs. kgg

Sounds like an older one. Like with any used machine you have to go over the machine visually for sighs of worn out parts or poor maintenance as well as listening / feeling for rough operation. Also in the older ones don't forget to check the timing belt as it maybe worn out or dry rotted. kgg

I also think that is a good price for the Singer as it does look in pretty good shape from the photo. If you take a look at the topic "How Singer 29K's should operate" it may help you when you go and see the one you are interested in. The one in that topic with the link to a video is of a 1998 Singer 29K and it is not as nice or smooth as my other 1949 Singer 29k. HowSinger 29K's should operate. kgg

I wouldn't hesitate to take a good used Juki over a new clone. Most of the new clones in this class are of the older Juki LS-341 even though some even call their clone a LS-1341 but in reality??? Photo of Juki LS-341: http://www.nickosew.com/details.php?id=508 Photo of Juki LS-1341: https://sewinggold.com/product/juki-ls-1341s/ Buying a brand name like Juki down the road will be a better investment, parts and accessories are readily available, resale is higher and it is easier to sell when you want / need to. Juki parts are guaranteed to fit Juki machines. kgg

Your right the smaller bobbin shouldn't be a problem. I would be more concerned at the choices of thread sizes the DSC-245 can accommodate. kgg

I thought it was the DSC-246 and the DSC-246-7 that took the double capacity bobbin. kgg

I made a simple gauge using my 3 D printer which actually works, surprised the hell out of me. I tested it against some veg tan leather that was factory tagged with the size and weight of the leather before I bought it. This probably is not an option for most but I think any of the hobbyists gauges really are only for edge measurements so even your inexpensive slide type like Tandy's Leather Thickness Gauge ( https://tandyleather.ca/products/leather-thickness-gauge ) at $4.09 CA would probably work just fine. The only drawback with calipers is you have to figure out how thick an ounce of leather is when measured in mm and divide your measurement by 0.4 as I think an ounce of leather is about 0.4mm. kgg

The main drawback is the max thread size as I read the spec. to be from V33 (Tkt 80) to V69 (Tkt 40) and as usual with the Juki's they rated their max needle size for one thread size above at a #21 needle which could technically accept a V92 (Tkt 30) thread. Also I read the spec as having a small bobbin. I would look for in the Juki's an older Juki LS-341 or LS=1341. kgg

I missed that one and with the OP being in Canada they are $53.99 CA at Tandy. Much more reasonably price then the buckle guy price of $96.05 or $122.59 CA. https://tandyleather.ca/products/pocket-leather-gauge?pr_prod_strat=description&pr_rec_pid=4527302475907&pr_ref_pid=4527285600387&pr_seq=uniform kgg

You can get one like you have shown from the buckle guy for $96.05 US ( https://www.buckleguy.com/tg-25p-leather-thickness-gauge/ ) there is also a video of their gauges on youtube of them gauge having both measurements: https://www.youtube.com/watch?v=zjJVqhBJW2E kgg

I would assume the stroke, type of sewing (leather or fabric) and the thickness of the material would be major factors in selecting the needle system. Too long or short a needle would cause the hook to miss properly picking up the thread. The thicker and tougher the material would require a larger diameter needle to prevent the needle from bending, deflecting or strikes. To allow for proper needle to hook clearance I think most sewing machine manufactures give a clearance range to best accommodate needle sizes within a needle system that the machine was designed to sew. Like the Juki DNU-1541S needle to hook clearance is range from 0.02mm to 0.05mm. Being able to fine tune the clearance could be a real benefit if you were only using one size of thread and needle with a certain type and thickness stuff. The problem is if you change the needle size you could get strikes or skipped stitches. For domestic machines I think a bigger problem would be if you set the hook clearance for a needle with a scarf and then changed to a needle without a scarf as the hook would always hit the needle shaft where the hook thinks the scarf should have been. Going the other way probably would be a problem. kgg

I think the portable walking foot machines like the Sailrite and others, as they have pretty rough feet, would probably leave marks. Since you are in Europe I think finding a Alder or Juki would be easier in the Brand names or one of their clones. What country are you in as someone maybe able to direct you towards something available in your area? kgg

Totally agree, Chris has good prices on parts, machines (Juki and clones) and servo motors. I have bought my Juki's 1541S and 1181N from him as well as his clone version of the Juki LS-1341 and have always been pleased both the price and service. Seems on high, high end of pricing. I run 550 watt brushed servo motors, the ones with the little round speed dial, on all my machines with no problems. I think most of the brushed servo motors are probably made the same and probably in the same Chinese factory just with a different branding name stuck to the side. I like the simplicity and proven tract record of the brushed motors. kgg

You forgot "Tinkers Delight" as you did make some changes to get it motorized. kgg

I think they are using the " Gunze Count standard " where the larger the number the thinner the thread for a given number of ply. Those sizes would be typically seen at your local fabric store in those small domestic size spools. The number is referring to the weight of the thread but not the number of cords (piles) that make up the thread. Where a #30 2 ply isn't the same size as #30 3 ply but is labeled as #30 weight. Confusing??? From the needle size the machine should be able to handle correctly thread up to V69 (T70, Tkt 40). kgg

Since both suppliers are close I would check and see what additional parts are supplied with the machines like 1) Deburring tool to remove burrs off the inside of the knife 2) Metal roller to get rid of the material that builds up on the outside of the grinding / sharpening stone, I think Consew calls theirs something like Super Radar roller. If both are equally equipped then it is down to whoever gives the best price. kgg

Thread information can really send you down a never ending rabbit hole. Particularly when you compare single to two or three core. kgg

Depending on what they are making and if they are using a single or double needle machine they can assume they are using for single-needle sewing machine the Z-Twist (Left Twist) or they could actually twist the end of the tread thread and see which way it starts to unravel. Besides the size, type, weight and yards or meters of thread information on the label I think the most important information is missing. How many twists are there on that spool of thread per yard or meter not how many yards are on the spool. With more twists per yard you get a smoother stronger thread which costs more to make and buy but should give you less thread related problems. kgg

A short video or a couple of photo's would also help to narrow your problem down. I am going to assume the feet you installed are similar too: ( https://www.amazon.ca/dp/B07DLM7LMY/ref=redir_mobile_desktop?_encoding=UTF8&aaxitk=b31bc0359e2199439acb987303abc3b4&hsa_cr_id=6896265850101&pd_rd_plhdr=t&pd_rd_r=5e2bf340-8f69-4fd7-beb4-add8a7c89d2d&pd_rd_w=FiTjG&pd_rd_wg=uH38g&ref_=sbx_be_s_sparkle_mcd_asin_2_img ) A couple of good video's for your machine which may answer some of your questions would be: Pressor foot install: ( www.youtube.com/watch?v=1o-WTYIKpvw ) Pressor foot tension: ( www.youtube.com/watch?v=7BdkLXoqu1Y&list=PLR4xEBIfN8Fyf6cjerMhAvwqClVzx8Zbc ) Also as the material being sewn becomes thicker you would need to reduce the tension on the pressor feet. The needle you are using (110/18) is incorrect for V92 you need to change to at least a #19 or 20 and in thick/tough materials a # 21 or 22. Are you using a leather needle (135x16 ) or a fabric needle (135x17)? kgg

Personally I hate most pastie type greases as most like lithium white grease are dirt magnets and you typically see the mess like what you have shown in your photo. Normally I choose to oil regularly with a synthetic oil concoction on my sewing machines but on those odd occasions that I have to use a grease I still prefer to use a light coating of synthetic gear grease. I find the synthetic's give a smoother operation to gears and bearings. kgg

Option suggestions: 1. Why not make your own belt. I just purchased some 10 meters (32.8 ft) of 6mm diameter Rough Surface Green Polyurethane off Amazon.ca for $28.79 CA ( https://www.amazon.ca/gp/product/B07W5L7NPV/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&th=1 ) plus tax to make a new drive belt. This will be the main drive belt from a repurposed sewing machine motor a Rex 550 watt servo motor for my new to me Atlas lathe. 2. Buy couple off Amazon they are cheap, two for $14.99 CA ( https://www.amazon.ca/CKPSMS-White-Industrial-Sewing-Machine/dp/B08CXZBCXZ/ref=sr_1_2_sspa?crid=3NE9LYGBI4UIM&keywords=56%2Binch%2Bsewing%2Bmachine%2Bdrive%2Bbelt&qid=1642740205&sprefix=56%2Binch%2Bsewing%2Bmachine%2Bdrive%2Bbelt%2Caps%2C115&sr=8-2-spons&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFTSjEzOTRBRFBOMUomZW5jcnlwdGVkSWQ9QTA5MDI5NjkzSFBFUElNN1lYNTdNJmVuY3J5cHRlZEFkSWQ9QTA2NDE5ODgzNkpLQTJETjVNS0hYJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1 ) kgg

Some servo motors do have a reverse rotation switch on the back side. I have a Rex 550 watt servo with this reverse rotation direction switch while my other servo's don't have that feature. kgg

Looking at the manual for the SC-9 and the CP-130 (my search: juki with cp-130 controller wiring and found a good manual called "Control panel CP-130 INSTRUCTION MANUAL - Amazon S3" at s3.amazonaws.com.) and yes it is an overvotage error. What I did notice is there are three wiring diagrams. One for single phase 100-120 VAC, One for single phase 200 - 240 VAC and One for 3-phase 200-240 VAC. With the E11 are you sure it isn't single phase 200 - 240 VAC not 3-phase 200-240 VAC? kgg

I am not familiar with that machine but for those dollars I would be concerned with the lack of dealer support and down the road for repairs and access to replacement parts. Maybe better off getting a good used machine that has dealer support. kgg

What is the model numbers of the Juki's??? as the manual for those models may help. kgg