kgg

I use inline/straight binders single fold and double fold from 1/4" to 3 1/2" on all my machines whether they are flatbed or cylinder arm. The main advantage of a 90 degree binder is that it should be able to do tighter corners then a inline/ straight. The disadvantages of the 90 degree binders are i) they cost a lot more then your inline/ straight. ii) you can't on most adjust the tension on the tape at binder itself. The main problem I think you are having is poor back tension on your tape and the path the binding tape travels through the binder is to wide so you are getting tape slop. Are you using your binding tape with a vertical or horizontal platter or just letting it drape to the floor?? Any photo's of your binding setup???

Did you get in contact with Techsew and how did it work out? kgg

My experience is that you can not burnish chrome tan. I use a soldering iron after lubing the edge. kgg

Very nicely done and a great use for those old circular saw blades. What did you use to cut out the shape of the old saw blade? kgg

A couple of questions: i) What size of thread are you using? ii) What size of needle are you using? iii) how thick of material are you trying to sew? iv) Does it happen on straight runs or when doing curves? kgg

At the max of 3 layers of 8oz the leather would be approximately 3/8" thick. i) That means if you purchase a upholstery class machine and depending on the toughness of the leather you would be at the max sewing capacity. Another factor that you did not mention is the max size of thread you want to use. If you hand sewing chances are you are using a thread larger then V138 probably closer to V415 or higher. ii) Typically upholstery class machines at max sewing capacity will handle up to V138 thread. The Juki DNU-1541 S is compound feed ( needle/ presser foot / feed dog moving the material ) ans is an upholstery class flatbed machine. Costing new about $1800 USD plus shipping. The Cowboy 3200 is a compound feed ( needle/ presser foot / feed dog moving the material) 10.5" cylinder arm Class 441 machine which is rated for up to V346 thread and up to a 1/2" thickness. Costing new about $2200 USD plus shipping. The Cobra Class 4 is a compound feed ( needle/ presser foot / feed dog moving the material) 16.5" cylinder arm machine Class 441 machine which is rated for up to V415 thread and up to a 7/8" thickness. Costing new about $2900 to $3900 USD depending on the accessory package and shipping. Another alternative would be a Class 441 that can handle V415 thread but is a manually operated one arm bandit like the Tippman Boss (~$1000 to $1200 USD), Cowboy Outlaw (~$1400 USD) or the Master Tool Cub (~$2000 USD) plus shipping. Another thing to take into account is the needle system as the class 441 machines use 794 needles while the uphosterly class machines typically use 135 x 16 needles. A rough comparison between the two needle system would be the 135 x 16 would be a 1 1/2" finishing nail versus a 794 would be similar to a 3 1/2" finishing nail meaning there is going quite a difference in the hole size in the leather. kgg

Funny thing I NEVER use sewing machine oil in any of my machines. I use a formula of synthetic motor and synthetic transmission oil. If I am flushing a old machine out I use a formula with more transmission oil to get into the bearings and remove any dirt/ etc. I find the synthetic oils lubricate surfaces much better, reduces friction and quiets a machine down particularly an old machines. A old sewing machine mechanic who worked at a factory where machines were used 24 / 7 used straight transmission oil to keep the machines cooler so they could keep up with the sewers. To answer your question an oil at your spec is similar to 5W oil at 20 C based on the chart ( https://imgur.com/DDA5MJW ) kgg

@Dwight , @Hildebrand I'm sure once things settle down @Johanna will let us know the site is up and running properly. Please keep in mind rebuilding a site after a hack can be very time consuming and we are lucky it is functioning at all. kgg

For the reasons @Wizcrafts gave the simple answer is NO. I would suggest a walking foot machine like the Juki DU 1181N. A new complete setup, machine, servo motor and table is about $1400 USD used???? I use my Juki DU-1181N to cover off the thinner stuff the Juki DNU-1541S doesn't like.

I think I would use: i) an off the shelf hollow linear shaft as they come in various outside and inside diameters. I guess a shaft with a 3/4" ( 20mm) OD and a 3/8" (10mm) ID would work. If the shaft isn't large enough add some form of a grip. These shafts are really available off places like Aliexpress and are mostly used for linear movement. An example would be ( https://vi.aliexpress.com/item/1005008313729816.html?spm=a2g0o.productlist.main.1.7f1edY5sdY5swH&algo_pvid=da5d617e-a98c-46cd-b478-14026027a4f7&algo_exp_id=da5d617e-a98c-46cd-b478-14026027a4f7-0&pdp_npi=4%40dis!CAD!26.96!13.48!!!133.20!66.60!%402101e9a217380630172501546ef44e!12000044581316320!sea!CA!3463193163!X&curPageLogUid=rV9wvFNWFsW5&utparam-url=scene%3Asearch|query_from%3A ) ii) 3D print a shaft with comfortable outside diameter for my hand with the correct inside diameter to accommodate the stamp. Cost would be pennies to make. Me being me I would do the 3D printed method. kgg

@Johanna that you for all the hard work that you have put into getting the site up and running. Damn Hackers there's a special place for them. kgg