Singer 31k48

[hugh123]

@Tastech back again. The 31k48 sat on marketplace for another couple months so I talked the price down a bit and went and tried it. It stitched 5 mm thick like it was nothing and even up to about 7-8 mm. So I went ahead and bought it. Now my question is what needles do you use and up to what size can I run? I received some shmetz 18s with it which I understand could run M40(69) or maybe M36 thread, however if at all possible I would like to run M20(138) with a 22 needle, just wondering whether you've tried anything like that. What size thread can I run in the bobbin? If I could run M36/Tkt92 I would be happy. Also it is extremely fast- what servo motor do you run and could you maybe give me a link? thinking that may be quite helpful in the near future.

Thank you.

Hugh

[Tastech]

@hugh123 My machine uses a 16-257 needle . I dont remember if this is standard or if i tweeked the needle bar to line up  so i can use the same needle on all my machines .I use the 16 for tkt 70 thread . For tkt 90 an 18 might do it but a 20 would be ideal  a 22 might leave too big a hole . You may have to adjust the bobbin tension to suit .

I use a 750 watt servo motor  i got from ebay . I got the slowest one i could find . I believe there are 2 versions with different speeds . I also have one on a treadle which is a modified 29K patcher treadle . As i mentioned earlier the bobbins and bobbin case is different to the 31k-15 so get the right one . I got some spares on Ebay from china ( after making a mistake and getting the wrong size) .When i set one of the machines up with the new servo i also bought some bearings and pulleys to make a speed reducer but i don't need it so i have not installed it .

I forgot to mention in an earlier post the the difference between the 31k-15 and the 31k-48 . The 48 has a roller feed dog not the standard up , back and down feed dog.

look after the machine because parts are very hard to find and you will have to resort to buying a spare so you can rob bits off it .

 

[hugh123]

@Tastechthank you. Im having trouble finding a servo motor that looks like it will work. Could you point me in the right direction?

[Tastech]

@hugh123 this is the one i got 

https://www.ebay.com.au/itm/203842070658

If you search sewing machine servo motor on ebay you will see this type come up everywhere .  There is a difference between them such as watts and top end speed . I looked for the lowest speed and highest wattage . Note that the speed range i chose is 500-4500 rpm and wattage is 600W . Some state that their range is 0- 4500 rpm but i think they don't quite understand what they are talking about . I am happy with both the power and speed . I hardly ever run it above minimum speed which is fine for me . To run it even slower i just pulse the foot pedal and it gives me a stitch at a time .One thing to note with it is that you can bolt it straight on where the existing one was but the pulley did not line up so i moved it about 20 mm left or right . To get the right position i put the motor upside down on top of the table bed and inline with the slot and marked and drilled the holes from the top and then bolted the motor underneath . I didn't use a set length fan belt but this silicone rubber stuff that you cut to length and insert an aluminium joiner to connect the 2 ends . I have no idea what the product is actually called but my local industrial supplier has it in stock . Which reminds me i need to get a few meters for some machines i have restored . The diameter is about 7 mm but comes in 3 sizes .

In case you were wondering i have fitted an after market roller on the foot but had to lift the foot up so it would fit . Pretty easy to do but if your original roller is fine then just leave it .Because it would be of much higher quality than a new one .

From memory  i got some spare bobbins and bobbin case on ebay and they were listed as a singer 31K20 . The 31K15 looks the same but the bobbins are not as deep .Both machines are built on the same basic body but have a few differences the bobbins and bobbin case being one of them .

If you have any problems sourcing them let me know and i will go through my purchase history and take some measurements and see what i can find for you 

Regards 

Tas

[hugh123]

@Tastech thank you for the help. Another question now. Shortly after purchasing, a 31k15 has now popped up for sale. Is there any real point to having both? I read somewhere that the 15 can run a slightly longer stitch? It is a presser foot not walking foot or roller. How hard is it to convert it to a roller feed? Is it my understanding that you can’t convert to walking foot. 

[Tastech]

@hugh123 You are correct . there is no way to convert to a walking foot . However converting to a roller foot is easy . I have a roller foot on one of my machines that is not a conventional roller wheel but a flat foot with needle bearings built in . I got it on ebay a couple of years ago as an experiment and it works fine but its a bit hard to see whats going on underneath so i use it for a specific purpose which is doing french seams . From memory it bolted straight on with no foot height adjustments .

below is the link . Feet are generally universal and will fit most generic machines 

https://www.ebay.com.au/itm/365600908899?_skw=roller+foot+for+singer+31K-20&itmmeta=01JWXCQJ49B77637G3JE4XYEEN&hash=item551f832663:g:7IYAAOSwhx5oI~hn&itmprp=enc%3AAQAKAAABAFkggFvd1GGDu0w3yXCmi1fCN2aP9mPAusXtjaGkljFugJUoWrdFrw4oueyVnNjUGkLMsqw2A6ARqmDzLoQ65%2B6VKZ5BpJTIWHqUr1gsAOKSLFs8TQ7CYKhMETxipEaei3vvBp2b%2F91N8AvpaCQMLo4Vt%2FACuoad%2B1uTF%2FZhtZZe4nyAKUA%2BakPAP8b4jzIepqj%2FPyMITWByc4pS5%2B7vzVZkJLYamjy3tohmqev4LqOx4N3YrFdOSZLuyKw7jk9yoBvIxS%2F6rUjcjTQfAKRfpHL7MYjwrt9WDEaUN7Bgm7pWJqhF0m4BK0OBfFbvFjZpDAE2byPoGcXJAFcLL9q2Opk%3D|tkp%3ABk9SR6yi3qznZQ

I also have converted another machine with a conventional roller foot. You will have to replace the feed dog as well as the roller and make a height adjustment to the foot bar . This foot however will not fit on the 31K-48 because it has a different needle clamp and the thread hook touches the roller when fully down . 

https://www.ebay.com.au/itm/354875933078?_skw=roller+foot+for+singer+31K-20&itmmeta=01JWXCQJ49JEFKG7SBTM0GYEDA&hash=item52a0410196:g:qDAAAOSwvsBkmk8w&itmprp=enc%3AAQAKAAABAFkggFvd1GGDu0w3yXCmi1e%2F5qCmG6xFw0AmKOEDIWLEe0meYXmfQ2BKpJtZ1P%2Bh48FCaYQZxULdwlEtyKbEMBeLpidUIA45OPgpgjVKM7yJB2L4LXfRmBZyQDRrRs5L67GNxP206vL3mdP1QxDH994bxrJCjnO%2FS1Jl%2BA2SE%2FAYNaXNlXFo1vdRbo%2BgC6k3D%2Fh79FmOJRI7H8SiRghTvt98TlD4e62mktu678ExQ%2Bbj%2F27xXANP%2B6RmhCZ4GgUeP3EeIlhQy0YPye%2BwjIuW7R7lER0emGv9yKVHvmY1ejsdzEz3LiHr4EZfaEYdfrV2SVnFAddYtRhsNJ26bgZMiEQ%3D|tkp%3ABFBMqqLerOdl

Its up to you which one you think will suit your need better.

If you do get the 31K-15 ,compare the bobbins and case with the 48 and you will see what i mean about difference .Its only a couple of millimeters but they are not interchangeable .

[Tastech]

@hugh123 Just found this while searching ebay . It looks like it has potential but i don't know how compatible it is with a standard feed dog . I ordered one to experiment with.

 https://www.ebay.com.au/itm/167507136396?_skw=roller+foot+for+singer+31K-20&itmmeta=01JWXCQJ4AGJVPYNWVW18KNB7V&hash=item2700340f8c:g:ldQAAOSwP9ZideG~&itmprp=enc%3AAQAKAAABAFkggFvd1GGDu0w3yXCmi1cEIlHfb8sInkPmjL0p%2FgNQ4XNRdPNI1GJi9YJ2%2BiJnSpLXr%2FfmfFisNgsVgZbN367LwL9iJlX8j1qKvTZIwws4AnXkZGVjE3gKiNW5kOmW5Sp5RkXNueimLJ6w1KjggajzRI%2ByQEp4iZyzl%2BY3BR1Cd4levH6VmZJ5b6K34i2YchyzuzaUHze%2Bgfm2vSgZbisY6vDaEcLUibwhGn7VklrOP5rskMWcyUHIr9PUnAErYBrrnOrKNdP401UXFtwlFKEhj3%2FlVcJZKwX87HxSA67keTr2nzQ0g5aIFTbS10%2B9%2BijHvU6vG4hvSxLlV7f5CzA%3D|tkp%3ABFBMrKLerOdl