Hot Rod Forum banner

Servo Motor MOD: DIY Easier Speed Control

17K views 27 replies 8 participants last post by  John long 
#1 ·
I am new to sewing and recently purchased a Seiko STH 8BLD-3 and I have spent many hours reading here on HotRodders.com, on Leatherworker.net, and on DIYTactical.com, and thank everyone for sharing their experiences.

I hope, with this post to pay back a little and make a few people really happy like me. This MOD for me ranks up there with best Xmas present ever... in July, no less.

In my research to learn more about my new sewing machine I ran into a lot of posts of people unhappy with their servo motor's speed control, this included me.

I was lucky one day and found a post on Leatherworker.net where a member named DDahl - Dave had used a paper and pencil gradient MOD to give a wider more controllable range to the speed controller of his servo motor.

Here is the link to DDahl's post that motivated me to make this how-to. (Thank You! Dave)
Question About Servo Motors - Leatherworker.net - Page 2

Amazing to me, Dave's post didn't stir much conversation or motivation, I attributed that to peoples fear of modifying things.

I made this video and how-to to show how easy this MOD really is and hopefully make a lot of people happier with their machines.

In addition to the video I have photos that can be use as a guide while preforming the modification. I will also post updates and tweak the how-to as needed and if people participate, post a list of servo motor models that work well with the modification.

Enjoy!


SWFLholsters » Sewing Servo Motor: DIY Smoother Speed Control MOD




P.S. I am not a writer and struggle with things like this, if anyone sees errors or has suggestions on how I can improve my writing to be more clear please let me know. :)
 
See less See more
#2 ·

Hmm...That's pretty interesting. I can say that the transition from slow to fast on my SewQuiet 5000 leaves a little to be desired (though it is TONS better than the old clutch motor).

I might give this a try once my warranty period expires. The nice thing about this mod is that you stay out of the 'meat' of the assembly and you can put everything back exactly to original if you don't like it.

Interesting indeed...
 
#4 ·
Wow. SafeAir. That isn't just interesting, that is absolutely fascinating. Thanks to DDAHL for figuring this out and to SWFLholsters for all his trouble to make such a well done and informative training aid. This has got to be one of the most interesting ideas I have seen. Even though I am really happy with my SewQuiet 5000 it would be great to have the more gentle ramp up and broader speed range. I don't see there is anything there to effect warranty either. It appears to have all the upside potential without any down side.....Can't wait to play.

John L
 
#3 ·
Yes, this is very interesting, but I'm still at a loss to understand why there are so many problems going through the speed range just using the foot pedal. My servo motors can all do exactly what is being described just with the foot pedal, but I don't think mine are optical. I guess it has something to do with what you learn on. I learned on machines equipped with clutch motors, so maybe that has something to do with it.
 
#6 ·
Dan, I believe our SewQuiet 5000's are. I looks to me like they have the same controller as the one in Holster's video. I you haven't watched it at least take the time to.

The reason I wanted to answer your post was to explain the interest in a modification like this for amateur trimmers. I have for years been challenged to do all of my own work when building a car. I have had an English Wheel since 1989 because I wanted to learn to do my own sheet metal work. The car I have now has been pretty much built by me. I do my own metal work, paint work and interior work. I am never going to be the worlds best metal former, painter or trimmer. Jack of all trades and master of none applies to me for sure. Most of us who only do our own work are never going to have the cockpit time to become experts with a sewing machine. Anything that we can do that provides us with better control of the machine is a giant plus. Those of you who are experts in your trade have gotten there by spending years honing your skills to get to level you are at. We amateurs will never achieve that level but can still do some pretty good work. Control of the machine adds to that immensely.

John L
 
#5 ·
I am new to sewing and recently purchased a Seiko STH 8BLD-3 and I have spent many hours reading here on HotRodders.com, on Leatherworker.net, and on DIYTactical.com, and thank everyone for sharing their experiences.

I hope, with this post to pay back a little and make a few people really happy like me.
Welcome to the Forum SWFLHolsters. I don't remember when anyone's first post has been as interesting as this. Thank you for the trouble and effort you have put into this and for sharing it with us here.

John L
 
#12 ·
John, thank you for the warm welcome I appreciate it.

After reading thread after thread about the sensitivity of the digital servos and then seeing first hand the results of DDahl's MOD, I was so thrilled I just had to share the how-to.

Now with Cronko's success I am so happy that the effort to put the guide together was totally worth while, because I am sure Cronko's success is the first of many.

Can't wait untill you get back from Street Rod Nationals because I know you are going to be on the list too.

Thanks again!
Larry
 
#10 ·
I tried this trick on my SewQuiet 4000 today, and I can confirm that it works. The Enduro brand motor in SWFLholster´s video seems to be a lot more sensitive than the SewQuiet 4000 though. I tried it the way shown in the video with just a paper and some gradient from a pencil...it didn´t work because the light from the sensor was too strong. Then I took the thin cardboard from a pack of cigarettes...that worked better but not as good as I was hoping for. I was surprised when I saw the light right through the cardboard...must be some kind of laser-light I guess??

I ended up taking this cardboard and then started to laminate it with the sticky end of Post-it notes, sort of staggering the Post-it notes so the whole thing became thicker and thicker to one side...that worked, and I was able to fine-tune it too with the pencilmarks. The way it seems to work is that when the sensor gets light no current is passed to the motor, and when you start to shade it of gradually, more and more current is passed through it.

It worked and now I have adjustable speed through the whole stroke of the lever. But just as SWFLholster says...you have to experiment with the paper thickness/gradient a little to get it where you want it.

Thanks to SWFLholster and DDAHL for sharing this trick.
 
#13 ·
SWFLholsters,

If you think my little explanation can be of any assistance to someone, then feel free to use it in any way you like.
I´m sorry I don´t have a camera so I couldn´t take any pictures of it, but once you open the Sewquiet then the rest of the work is rather self-explanatory after watching your excellent video:thumbup:

I did this with the motor still on the machine, but of course it will be safer and more comfortable to take the motor off and work with it on a table. Also remember that as soon as you start to experiment and put your pieces of paper in the sensor, the motor will start...so take the belt off the machine, and keep your fingers away from the pulley.
 
#14 ·
Good stuff Cronko. I have been very pleased with my SewQuiet 5000 on my Adler 267. I think this will be the icing on the cake. The only thing I have wondered about is should we be looking for a more permanent material? 5 years from now the paper or cardboard may need to be replaced. Not that it will be a big deal to do so. Isn't it amazing that the manufacturer would not have done this in production?

John L
 
#16 ·
John,

I´ve been thinking the same thing about the material...the paper/cardboard doesn´t feel very permanent even if it`s easy to do all over if/when it fails.
I was thinking of some kind of plastic while working on my machine, but was too excited to get it done in a hurry...so I went the paper-way:)

Maybe it´s possible to cut strips from some translucent plastic lids or cans, and then try to paint them in different thickness/gradients?? I guess a guy that can handle an airbrush could do this easily, but that´s way beyond my skills:)
Or perhaps take a strip of plastic and try to sand/file it down to a wedge-shape in order to get it to let more light to pass through it?? If someone is willing to try and comes up with a more permanent solution, it would be intreresting to read about it.

I agree...it´s amazing that the factory didn´t do this to begin with, but I guess they are trying to cut costs in China too these days??
 
#17 ·
Arrgh...it's past 10PM and I just got home from work but now I want to crack open my SQ5000 and attempt this mod.

From the beginning I have had a thick piece of white sheet styrene in mind for use as the diffuser; I've got a bunch of it left over from another project.

I still can't believe that this went largely unnoticed on the very original forum it was posted on!

Ok...I'll be back in an hour or two (runs off to get his camera and styrene).
 
#18 · (Edited)
...(runs back to the computer) That was fast! I actually finished a half an hour ago, so it takes about a half an hour to do this mod if you take 3 tries to get it right.

I found the thick piece of styrene (about 1/32") to be too thick, but I had a piece of thin styrene...maybe .010" or so that I spray painted a black stripe on. I also shaped the styrene so that it would gradually and increasingly block the light source as the pedal was pressed.

The results were unbelieveable! This was what I was expecting when I bought the SQ5000! A nice, gradual build up in speed from 1 to the programmed speed over the full range of the actuating lever.

In the end, the thickness or translucense of the diffuser I made probably didn't matter a whole lot--I found that the diffuser I made was mostly the same shade of gray and that the gentile speed control was due primarily to the way I cut the diffuser so that it would more gradually (than the original) block the light the further it was rotated into the light sensor.

I know that this was the principle of operation of the original factory diffuser, but they got the shape wrong...That arc cut into the diffuser is much too sharp--it needs to be a long, gradual arc. I think you could probably cut the original diffuser so that it blocked light transmission more gradually, but I didn't want to test this out by making any permanent changes to anything because my servo motor is still under warranty.

Thanks again to Larry for cluing us in on this!

Spray Painted Styrene:


New Diffueser Stuck To Old Diffuser Using Ultra-Sticky Seamstick Canvas Basting Tape:





 
#20 ·
...

The results were unbelieveable! This was what I was expecting when I bought the SQ5000! A nice, gradual build up in speed from 1 to the programmed speed over the full range of the actuating lever.

Excellent news, now we know the popular SewQuiet 5000 works and the list grows by one.

SewQuiet 5000
SewQuiet 4000
Skyrit TN-411 (looks very similar to a Consew)
Enduro Pro SM600-1

I just did a production run of a project last night and I am in kats *** heaven with my machine. Until last night I had only tested the mod on scraps but last night was a true test and man what a difference, the smooth control was absolutely incredible.

This project is a mix of go slow and accurate to long straights and prior to this I would just leave the speed at 3 and limp along on the straight stretches. Not anymore, now I can slowly build up speed to a controllable high speed for the straights and come to a crawl for the tight spots. Productiviy increase here I come. :thumbup:

I'm off to catch some Z'zz have a great day all.
 
#19 ·
SafeAirOne,

Nice to see that it worked out so good for you with the plastic. Altering the shape of the plastic strip instead of the translucency makes it even easier:)
Looking at the pictures of your control-arm, I see that the factory have tried to change it a little from the earlier model. On my SewQuiet 4000 the arm is just a square piece of steel, while your SewQuiet 5000 at least have a radius on it.
Now it´s time to run and find some plastic....:)
 
#21 · (Edited)
Update:

When I tested it after buttoning it up last night, I was hitting a max of "11" with the machine set to 15 so today I popped it open and adjusted the shape and position of my...I was calling it a diffuser, but it's more of a light blocker...so that I could hit "15" at full travel..

Here's the size, shape and position of the light blocker that did it for me--It starts after a half centimeter of lever travel, will hold a speed of "1" all day long and will hit "15" at the end of travel with a steady, predictable graduation in speed. NOTE that the arm is rotated away from the sensor just to take this pic--I positioned it correctly after the photo:

THE FACTORY SHOULD BE MAKING THE LIGHT BLOCKERS IN THIS SHAPE:
 
#22 ·
FWIW, last week I sent The Reliable Corporation an e-mail extolling the virtues of this better way to control the speed on their SewQuiet line of servo motors. In fact, it was mostly an e-mail of me going gaga over it and a link to this thread (and therefore Larry's site and the original "discovery" by DDHAL).

Susan, their Customer Service Rep, forwarded it on to their Service Manager, Nathan.

Even though they don't produce the motors or the parts, it'd be nice to see them have some 'correct' speed control arms made up and offered to users.
 
#23 ·
Just got back from the NSRA Street Rod Nationals. Could not wait to play with this. I used an old worn out "bondo spreader" which was a little too transparent. I added 3 layers of masking tape and shaded it with a pencil and then one last layer of masking tape. I had not seen the last few posts or I might have gone with SafeAirOnes's method but this truly worked great also.

Here are some pictures of what I did with excellent results.



 
#24 ·
It seems like I might give this a try using plastic from a gallon milk jug, sharpie marker, and a hot glue gun.

Plan B might be to use layers of duct tape to make a "flag" for the arm.

I'm having the problem where every so often, even though it is set at "3", my SQ5000 will surge to full speed for a split second on starting. Not every time, but enough to **** me off. :pain:

 
#25 ·
Glad I found this thread!

I'm expecting a new Cobra Class 4 in about 2-3 weeks so I can't wait to try this out.

My current Highlead/servo motor combo works fine for me and it isn't one of the digital speed controllers anyway.

Like someone said earlier, I've learned way more on here than I was learning hanging out at the upholstery shop tearing down furniture! :)

Bobby
Home Page
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top