bikemaniac

Hi Wiz, I will def be handsewing again and just use the old holes. Why do you suggest such thin threads? Is nylon stronger and more abrasion resistant than polyester? What is the difference between bonded nylon and non-bonded nylon? Lucas

Hi, I am struggling with my everyday boat shoes. After 1-2 years the upper sewing starts to fall apart: Due to the stress and abrasion in that area (it bends for every step), the heavy thread is slowly ripped in pieces. What type of thread (brand + name/model) can you recommend for this high stress area in order to permanently solve the problem? Lucas

Hi, Recently I bought myself a 31 year old car with vinyl seats. The seats are still in perfect condition with a soft supple touch to them. There are no cracks and the vinyl does not look dirty. I want to keep the car the next 20-30 years and I want to make sure the vinyl stays in that perfect condition. What conditioner should I use in order to keep the vinyl soft and non-cracking over the next decades? I read somewhere something about mink oil and mineral oil. I actually prefer a natural product. Can anyone recommend something that works? Thanks, Lucas PS: I am not looking for a vinyl cleaner.

I just wanted to add, that if I would buy a 8 pole 0,09kW motor which runs at approx 700 rpm nominal speed, then I could stitch as slowly as 10 stitches pr minute with full torque :-). Lucas

What I could do: Build a switch into my foot pedal ... but I just have not done it (yet). As soon as I depress the foot pedal slightly, it turns the converter into the standby humming mode. When I depress a bit more the machine starts sewing. When I fully release the pedal again, the switch goes in the off mode and the converter becomes silent. Lucas

Because I am using a frequency converter, the torque is constant between approx. 5 to 50 Hz ... in the US it would be 60 Hz. Between 50 and 500 Hz, the torque drops steadily. Between 0 and approx 5 Hz the torque is almost zero. Actually, it would be more safe to say I have full torque between 10 and 50 Hz and there is a slight drop between 10 and 5 Hz. But basically it means I have full torque of 5 Nm between approx 25 rpm to 150 rpm. If I want to go faster than 50 Hz, i.e. faster than 150 rpm, then the torque starts to drop slowly. I guess, when running at 300 rpm, the torque is 3 to 4 Nm. Lucas Ps: But if I want more torque I could just buy a 4 pole 0,18 kW motor and have 10 Nm on the main shaft and then maybe have 7 Nm at 300 rpm. My frequency converter goes to 0,37 kW so I could also buy a 0,37 kW motor and have 20 Nm on the main shaft. I would only need a slightly longer timing belt. A 0,37 kw motor is very common and can be bought used for maybe 50 USD.

Large converters are the most common ones in the industry: They get 3 phases in and 3 phases out while the operator can change the frequency. In my converter I get 1 phase in, 3 phases out, plus I can change the frequency. So basically my converter does 2 things :-). Lucas

Hi, Background: From reading this forum I decided I needed a leather sewing machine, but I was unsure about so many things. Thus, I visited Trox in Oslo for 1 day and had a look at his workshop, his machines and we had many discussions on my needs etc etc. Particularly I was interested in the small frequency convertor he had in his shop, but as I remember it was not powering a sewing machine. I went back to Denmark and had many thoughts on what to do. I decided to buy a Global WF1575 http://www.globalsew.com/en/wf1575.htm which I bought at Frank Brunnet in the Southern Part of Germany (http://www.frank-brunnet.com/). By car I drove 700 kilometers to his shop to get my machine and he introduced me to the machine and we spent a few hours on the setup so it would work properly on leather. Without knowing one single person in Denmark who can setup my leather sewing machine I had to know how to make changes if you change thread sizes, leather thickness etc. But I did not want to buy a motor from him. Not a servo motor and not a clutch motor and not an Efka motor - I wanted to make my own design. And Frank had a hard time understanding this. Thus, I only bought the head and some needles. I'm a mechanical engineer and have have had many projects with motors, frequency convertors etc. Thus, slowly the drive system slowly emerged in my head and I planned precisely how to do it. Without ever having used a leather sewing machine before, making a drive system for a leather sewing machine, I jumped right in. The basic setup was to use a frequency convertor, a 2nd hand foot pedal, an industrial 3 phase electric motor, 2 pulleys and a timing belt, and a bracket for attaching the motor directly onto the sewing machine. The reason for doing this was, I realized I never wanted to do any fast sewing and I only needed a setup with a max speed of 150-200 stitches pr minute. Purchase list: 1 ABB ACS150 frequency convertor with a max load of 0,37kW motors. Staying below 0,37kw ensures you will get a convertor that does NOT have an annoying fan. The frequency convertor is of the type where 1x240V is on the primary side (used in every European household) and the convertor splits the single phase into 3x240V besides being able to also changes the frequency from 0 to 500 Hz. Price 145 Euros. 2 A Cantoni 3 phase industrial induction asynchronous motor with a rated power of only 0,09 kW. It is a 4-pole motor with a max speed of approx 1350 rpm. Such a motor runs both on 3x400V but ALSO 3x240V. These motors are the most robust workhorses in the industry and can almosyt not be killed. Price 80 Euros. 3. A timing belt with a width of 10 mm and a corresponding large 80 tooth large pulley which a bolted to the hand wheel of the sewing machine. A small 10 tooth pulley attached to the axle of the motor. That would give me a gear ratio of 1:8. Total cost approx 15 Euros. 4. A used 2nd hand foot pedal from a domestic household sewing machine shop nearby. 10 Euros. 5. A 6mm mild steel bracket laser cut in a factory for bolting the motor directly to the sewing machine. I designed the bracket in a CAD program and sent the file to the company. Cost was below 10 Euros and it looks beautiful With a friend we cracked the foot pedal open to investigate the electronics. Based on lots of testing we needed to buy a new sliding potentiometer at a cost of 0,50 Euros. It was soldered into place instead of the existing potentiometer. So, with the current setup I can both run the machine from the foot pedal but also manually from the knobs of the frequency convertor itself. Everthing was put together, the cables were attached to the frequency convertor, I threaded the machine and after a bit of hand cranking on a piece of leather I engaged the frequency convertor and the machine just started sewing without any problems the very first time making beautiful stitches just like in Southern Germany. I am extremely happy that this has worked out and serves my needs perfectly - plus I have learnt so much during this process. I am now ready for my first project this Winter. Beware my motor is only 90W but that works perfect because I only operate the machine at 150-200 rpm - and not 2500 rpms. Due to the gearing ratio, I have approx 5 Nm torque on the main shaft of the sewing machine. I spent many hours on this drive project - and totally it would have been cheaper to buy a servo motor, cluth motor or something else already proven in the industry. But I wanted to do it myself and have a slow moving machine. With the setup I am now able to run as slowly as 20 stitches pr minute! The only annoying thing about this setup is the humm from the motor when engaged but not moving - this is just part of everyday life when using frequency convertors. Lucas

Hi, I got this idea - maybe somebody would like to have a discussion on the topic. Why not use an battery driven electric drill as a sewing machine motor? Specs: Use a standard portable Li-ion 12V, 14,4, or 18V electric drill and manufacture a bracket in such a way that the drill is inline with the main shaft (main shaft with pulley). Thus the drill is NOT installed below the table but as an extension of of the sewing machine. Advantages: 1. Drill is rather cheap - maybe use an old one you already have. 2. Should be a good solution if you don't sew all day long, due to the longevity of the electric drill motor. Maybe it is not an issue because modern drills are built for heavy duty construction work use. 3. I read somewhere online on this forum that 8 Nm of torque is necessary in heavy duty stitching. These modern Li-Ion drills have a torque of more than 50 Nm due to their planetary drive. The +50 Nm are only available at a low speed setting - I think 0-200 rpm or so. Almost all drills have 2 speed settings - slow and fast. 4. Typically, the drills come with 2 batteries. If one battery dies, you can plug in the other battery and start charging the 1st one. Charging nowadays is often less than 1 hour. 5. These drills have the full torque all the way from 0 rpm and up. 6. These drills have accurate speed control. Disadvantage: 1. You need to modify the push button of the drill and turn it into a foot pedal. Lucas

I ended up not buying the machine. Suddenly I had to pay 20% sales tax and so forth. Furthermore the listed shipping rate which I was expecting was wrong (too low). Thanks for all your comments. Lucas

Would it be wise to leave the brand new servo motor and buy an Efka servo motor (elsewhere) which should be able to operate the head at low RPMs?

I have the possibility to buy a used Juki TSC 441 It is not a clone but a real Juki. The sewing machine is equipped with a brand new 1HP servo motor incl needle position (Chinese). The machine comes with the head, motor and table but no accessories. The machine is setup for sewing leather. For me it is important to sew very slowly because I am a beginner. I know it is def. not one of those Efka servo motors. The asking price is 1400 pounds, approx 2300 USD. Problem: The machine is in UK and I live in Denmark. I only have the possibility to buy it and have it shipped without having seen or tried it. 1. What are the risks of buying a used original Juki TSC 441? 2. How easily will it be to do slow sewing - lets say 1 stitch pr second with such a servo motor incl needle position? 3. Are accessories compatible with the accessories sold for all the clones? 4. Is the price OK? Thanks in advance, Lucas

I'm following this post a bit now (I'm looking around for a machine myself): The Cobra class 4 should be able to use threads all the way from 69 to 415. Why is it that you have difficulties doing the thinner threads? Is it a Cobra problem only? Lucas

Hi, I have been reading quite a lot in this forum already trying to get an overview on sewing machines. On a hobby basis I have been sewing by hand for various small projects the last 15 years. Right now I'm working on my biggest hobby project so far: Leaf spring gaiters for my truck. I would estimate that the project has required me to punch approx 4000 holes and subsequently sew 4000 holes by hand. I know, this is quite ambitious, but I have the time to do it, however such a project incl designing, cutting, sewing etc will take up 2 weeks of work. For sewing I use the method with 2 rounded needles and a waxed polyester thread having a labelled diameter of 1 mm. My recent project can be seen here: http://forum.buschta...cht-t38764.html Previously I have also been confronted with projects where I needed to sew heavy materials such as multiple plys of jeans fabric, reinforced vinyl and heavy canvas, but these projects always stranded because: Most people own a sewing machine. Like I do: I own an old manual Pfaff with a hand wheel. But it is way too small for my hobby projects. This is why I'm considering a heavy duty sewing machine for my oncoming projects. I have some requirements: 1 I live en Denmark, Europe. The sewing machine should be rather easy to get over here. It is very easy for me to buy something in Germany, Switzerland, Austria, maybe UK, Sweden etc. I'm not just limited to Denmark. Maybe shipping from USA is an option, but then I have to pay taxes and duty etc which I don't like :-). 2 I'm not in desperate need of a machine. I can easily wait 1-2 years to get the right one. 3 I want the machine to be manufactured in Europe, USA or Japan. I don't want to support any Chinese products. Thus, I prefer a used German machine over a brand new Chinese machine. 4 It is my impression from reading this forum that I need a walking foot machine (triple feed), however I could use some advice on which type of machine. It is my impression that a cylinder bar sewing machine is the most versatile one: you can always fabricate a small wooden table yourself if you want to turn it into a flatbed. 5 I believe that I will never run into projects sewing leather/vinyl/canvas thicker than 10mm (3/8"). However it would be nice to use thick threads such as my waxed thread (without wax). I really have a hard time understanding thread designations, but I believe that 1 mm threads are something like #415 threads. Questions based on requirements: A I have found some sewing machines such as Juki 441, Adler 267, Adler 269, Adler 167, Adler 69, Adler 467, Adler 205-370, Pfaff 545, Pfaff 345, Pfaff 335, Pfaff 1245, Pfaff 1445, Singer 111W, Seiko CH8B etc etc. Those are just some interesting ones I stubled upon. I am very much open for other suggestions - even non motorized ones. Would it be possible to group them into maximum and minimum thread sizes to get an overview of their range? B If a machine is good at sewing leather, will it also be able to sew vinyl and canvas? Maybe with some minor modifications? C What type of motor is needed if you want to sew extremely slow, like 1 stitch pr second? Thank you very much for a great forum, Lucas