G+_Douglas Biggers Posted March 14, 2018 Share Posted March 14, 2018 A while back I asked about the hack/reusability of credit card terminals. I have since scored an older terminal (Nurit 2085) that, according to a processing company I talked to, is equivalent to a 2G cell phone(translation: virtually useless in today's market). It appears to be very potentially useful, and if/when I actually take on the project, updates will come. Anyway, on to my actual question: I bought a Janome Sew mini(great little sewing machine for less than $100) and would like to add lighting and a speed controller to it. From the service manual I was able to find, it look like the pedal interrupt electron flow between the wall wart and motor, but can any one confirm this? Link to comment Share on other sites More sharing options...
G+_David Peach Posted March 14, 2018 Share Posted March 14, 2018 What do you mean by a speed controller? Something separate from the foot pedal control? Link to comment Share on other sites More sharing options...
G+_Douglas Biggers Posted March 14, 2018 Author Share Posted March 14, 2018 Considering this model/line is the lowest Janome/Newhome goes, the motor is binary(on at full speed or off). The only speed control out of the box is stitch selection. I would like to add speed control for the motor it self. Link to comment Share on other sites More sharing options...
G+_Ben Reese Posted March 14, 2018 Share Posted March 14, 2018 I found the replacement motor, but no information about it other than that it's DC. If you could find the other info... Voltage, brushed vs brushless, continuous rotation vs stepper.... You should be able to figure out how to control the speed. My guess is a continuous rotation motor that can be controlled with PWM. Edit: forgot the link https://www.sewingpartsonline.com/dc-motor-janome-525621005.aspx Link to comment Share on other sites More sharing options...
G+_David Peach Posted March 14, 2018 Share Posted March 14, 2018 [Read this below, but, if you have time, give me a chance to look at a few of the sewing machines that we have at the house before you jump into something that may be more complicated than necessary. I will see how the speed controllers on our machines work.] Recently a friend's speed controller for a DC motor went out on his scroll saw. I stood there as he tossed it to the curb and into my arms. Here is my solution (which I asked help for a few months ago here, but never followed up). https://plus.google.com/u/0/+DavidPeach10/posts/YNw9iw6AFq4 There may be a simpler way, but this works great for me. [At the end of this post is a video that really helped me understand all that I'm about to say.] I bought the product from eBay that is linked in the previous post, but ended up not using it. This requires DC in to control a DC motor. But for my scroll saw I had AC in. Therefore I bought one of these: https://www.ebay.com/itm/10000W-220V-AC-SCR-Electronic-Motor-Voltage-Regulator-Dimmer-Speed-Controller-NJ/272996557997?epid=19011426303&hash=item3f8fdce4ad:g:jysAAOSwHYpaQfV9 This has AC in (can be up to 220V, but 110V works fine). Then it outputs AC as well. I ran the output through a bridge rectifier which turns it into DC. Here's the type I chose, but you could go with a smaller one. https://www.ebay.com/itm/MDQ-100A-100-Amps-1600V-Single-Phase-Bridge-Rectifier-Controller-Full-Wave-Diode/122731592456?epid=2273605830&hash=item1c935f7b08:g:qf0AAOSwlRZZzvGN Here's an example of a smaller one that I read would work: https://www.ebay.com/itm/2X-2-PCS-50A-1000V-Metal-Case-Single-Phases-Diode-Bridge-Rectifier-KBPC5010/322511377016?epid=2014685146&hash=item4b172d1278:g:~Y4AAOSwe8tXMfzZ What you have is 110V coming from the wall into the SCR motor controller. Variable AC voltage coming out (based on the potentiometer). The AC voltage out goes into the bridge rectifier. Then DC comes out of the rectifier to the motor. I watched several YouTube videos about this. But the one that finally made it all make sense was this one: He mentions in there that he had to change the potentiometer to get better control. I too needed a 200k pot to give me max control. This works great for my scroll saw. Even though I've been playing around with it for a while, I finally finished the project a couple of days ago. I get saw blades in tomorrow so I can start using it. Link to comment Share on other sites More sharing options...
G+_David Peach Posted March 15, 2018 Share Posted March 15, 2018 The foot pedals that I have take 110V AC in and output??? I didn't get anything out. AC nor DC. At least not that I could measure. It could be a PWM signal going out. If that is the case, then you might be able to hack a standard pedal and get it to control your DC motor. Here's a pic of one of my pedals. The other type that I have is very similar inside. Link to comment Share on other sites More sharing options...
G+_Douglas Biggers Posted April 5, 2018 Author Share Posted April 5, 2018 bit of an update: Finally opened up my machine, And I'm hoping the project will be as simple as I think it will be. The follwing album shows wiring, motor, and what I think will work as a flexible controller/potential kit. thoughts? photos.app.goo.gl - photos.app.goo.gl/cdCEd6wbr60Ce4P12 Link to comment Share on other sites More sharing options...
G+_David Peach Posted April 5, 2018 Share Posted April 5, 2018 Douglas Biggers It seems like, because this is a basic DC motor, that you could just use a simple foot controlled potentiometer to vary the speed. It would not have to be PWM (though PWM would probably work better). Link to comment Share on other sites More sharing options...
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