kgg

Nicely done repurposing old equipment. The only suggestion I have is if you can move the thread guide out about twice the distance from the bobbin and lower the guide hole down closer to the center of the bobbin it will fill the bobbin more evenly. kgg

Another one is the Craftplus Tipping Machine at $1000 ( https://www.ivan.tw/products/craftplus-tipping-machine ) kgg

Nice clean thread path so it should be good and your results are good. kgg

The 3L may fit but it is going to depend on the profile of the pulley on the Singer. Check the profile designation on the old belt. The object is to get the belt to fit well down in the grove to get the proper transfer so you may have to go to a narrower 3V. kgg

The possible down side of moving the thread guide to the inside of the face-plate is the thread may rub on the cutout in the front of the face-plate. By moving it to the inside you did change the angle of the thread to the needle guide, making it less restrictive. A photo of the front of the face-plate would be nice to see. kgg

When you remove the belts to relocate them to the correct pulleys: 1. Run you motor at the lowest speed for about a minute and then move the speed up in increments of 100 rpm and run it for about a minute every time you change speed. This will help better seat the brushes in the motor. 2. Replace the belt from the speed reducer to the machine to a proper sewing machine belt that will seat in the pulley groves to reduce possible belt slippage and better power transfer. kgg

I am not familiar with the Juki LZH-1290 machine but as long as the bed has the holes to accept attachments located to the right and centered to the right of the needle you should be a able to use a binding attachment. Using 3/4 inch binding tape would probably be best done with the zig zag set to zero ( 0 ) so the machine is being used as a straight stitch machine. If I'm not mistaken this is a drop feed machine. The question I have is why the Juki LZH-1290 rather then a 1541S or even a 1181N or is the zig zag feature an important need? kgg

In my opinion the #22 needle is good for V92 in thicker items or V138 in thinner items. A good cross reference for needle size to thread size table can be found at ( https://www.tolindsewmach.com/thread-chart.html ). I would call / email the vendors and ask them directly if their machines can sew what you want. kgg

I am not familiar with the Juki LZH-1290 machine but as long as the bed has the holes to accept attachments located to the right and centered to the right of the needle you should be a able to use a binding attachment. Using 3/4 inch binding tape would probably be best done with the zig zag set to zero ( 0 ) so the machine is being used as a straight stitch machine. If I'm not mistaken this is a drop feed machine. The question I have is why the Juki LZH-1290 rather then a 1541S or even a 1181N or is the zig zag feature an important need? kgg

The Seiko LCW-8 will take a #22 needle while the Juki LS-1341 will take a #24. kgg

The computerized machines are good at doing a lot of fancy stuff but when you see Juki dealers shy away from repairs and factories replacing them on a schedule it tells me that you should just strip the computer controls off and install a servo motor as Wiz previously mention. kgg

The main question is what are you planning on sewing and with what size of thread? The machines you have asked about are made for sewing fabric. The VEVOR appear to be a reseller of a wide range of Chinese stuff and have just put their Name on a clone machine. Support and parts maybe iffy. kgg

The synthetic transmission or motor oils have very little if any more odor then sewing machine oil these days. kgg

According to the Consew 206rb-5 Operating Manual ( Consew 206RB-5 Operating Instructions ) under Specifications section the machine is only rated for a #22 needle. That means it is rated to handle V92 in thicker materials or V138 in thinner materials. To use V207 you would need a #24 needle. I my opinion you would be much better off looking at a Juki DNU-1541S that is rated for V138 top and bobbin thread in thicker materials and is rated for #24 needle. kgg

In my area an old time repair guy uses transmission oil in machines when the owner wants the sewing speed increased to keep up with the operators to better get rid of machine heat buildup. kgg

I think at present time Juki is the main brand that most of the clones copy. They have been around since 1945. However not all their models are made in Japan some models are made in China. kgg

Nice hat I guess for those that don't know if they are coming or going. kgg

Which country are you in? If in North America a 4 wire could be a 220 volt single phase. When you see plugs missing it probably a good indicator that it was used in an industrial setting and directly wire into a circuit or the motor is shot. If the machine is in good operating condition plan on replacing the existing motor with a servo motor. A photo would also help. kgg

Nicely done. kgg

Which oil would be best for your machine, check the recommendation of the manufacturer for that particular machine. I think Adler recommends DA-68 for your machine. I don't know what the weight cross over is for this oil. The 32 and 22 I assume you are referring to is ISO 32 and ISO 22. The equivalent SAE for ISO 32 would be 10W and ISO 22 would be 5W. Sewing machine oil is a 5W white mineral oil that has a light viscosity that doesn't accumulate on the gears of machine. In my own machines I use a blend of synthetic oils but I am willing to take all the risks of not using sewing machine oil that the manufacture recommends. kgg

I think the 1541S would work but the CB4500 with the new narrow plate should also work well. kgg

I would keep it simple with a mechanical connection (wire / wire rope or chain) to a foot pedal and do the re-routing. The two problems I see with the linear solenoids are you have to spec the length of stroke and it is an all or nothing movement where with power on you get full stroke. If you need to turn the item like when doing a 90 degree turn you need to be able to lift the presser foot up slightly so you are probably going to have to force the presser foot level up by hand. A picture of your setup may help to get some suggestions. kgg

I have both the Juki DNU-1541 "S" and the Juki DU-1181N. First off if you are looking at a 1541 pay the $100 difference and get the 1541 "S" as it has a safety clutch. The main difference is the 1541 is rated for V138 on top and in the bobbin while the 1181N is rated for V92 but I have on occasion used V138 and both use the same size "M" bobbin but with different bobbin cases. The 1181N does not have a safety clutch and is a walking foot machine while the 1541 is a triple feed machine. The 1541 is a physically heavier machine and can handle heavier materials. The Juki DU-1181N costs about $1400 US and the Juki DNU-1541S costs about $1800 US. I have found that the 1541S doesn't like thinner stuff and those items are best left to the 1181N. You may want to check these video's on how the 1181N and the 1541S handle light, medium and heavy fabric. https://www.youtube.com/watch?v=IKJuKTrjsbw https://www.youtube.com/watch?v=4JES-2I7h3o This video will show the difference of the presser foot action on materials. https://www.youtube.com/watch?v=Elo3MeoOi5M kgg

Nice find. Natures choice. kgg

It is going to depend on what your trying to sew. Bonded Polyester has better resistance to UV and certain chemicals like bleach then Bonded Nylon does. Bonded Polyester is more flexible but produces more lint then Bonded Nylon. Darker thread colors in either bonded polyester or bonded nylon are stiffer then lighter colors due to the dying process. Excellent advice. Chinese threads are all over the place as far as quality and consistency with the 8 oz spools being the worst. Avoid the frustration spend the extra for a brand name thread like A&E (www.amefird.com) which are made in both USA and Canada. kgg