Trouble getting started with Seiko STW 8 help please

[bigsig11010]

I wasnt able to get photos to upload on my earlier request for help. I think I have that worked out now. 

[bigsig11010]

Sorry I dont guess my initial post got through. 

I have purchased a used seiko stw 8 which I understand is a consew 225.  It was sewing when I bought it. Got it home and set up and thought I threaded exactly as it had been and I tried to switch to a longer stitch length.  Now its breaking thread and missing stitches. See photo. 

 

I changed the lower pulley to a 2" to slow it down but its still too fast. I need help with the threading issue and recommended servo motor. 

 

On the lower tension the U shaped spring doesnt seem to come back to its lower position. It seems to stay in its up position. 

 

Any help or advice greatly appreciated.  

 

[MtlBiker]

Hi, and welcome.

I'm just a beginner myself so I may be totally off-base with my comment but on the photo that shows how you've threaded the machine it does look wrong.  But it is a little hard to see the exact detail from your photo (could have been a larger photo)...

When you bring the thread to the upper tension disc, it looks like you have the thread arriving at the 2 o'clock position (which is right) an then going counter clockwise and coming out at about the 7 o'clock position and going to t he second tensioner.  If I'm seeing that right, then you do not have it threaded correctly.  At the top tension disc the thread has to enter like you are doing and going counter-clockwise, all the way to about the 4 o'clock position and around the little pin that's there.  And from that point, down to the second tensioner entering clockwise at about (guessing) the 4 o'clock position.  From there up around to the spring and most probably you'd have to give a tug there to get the thread to pop over to the inside of that.

I hope this is of help.

 

[chrisash]

It looks right through the top tension disc but should then go clockwise around the lower disc, then pulled upright and towards the machine until it goes over a hook and back under the spring

[Uwe]

The threading looks right as they said but your check spring is either stuck or broken.

Here’s a little video that’ll go over the check spring function and how to adjust it.

 

15 minutes ago, MtlBiker said:

At the top tension disc the thread has to enter like you are doing and going counter-clockwise, all the way to about the 4 o'clock position and around the little pin that's there

@MtlBiker The part about going around the little pin is not quite right. Some YouTube video started this years ago and it’s being repeated all over the place ever since. I’ve not seen a single manufacturer manual that shows the thread path going around the pin. The pin is simply there to keep the tension discs from spinning. 

Edited March 10, 2021 by Uwe

[DonInReno]

Welcome to old machine land - where previous owners get tired trying to sew with poorly adjusted machines and sell them to the optimistic.

Often when something simple makes the difference between a machine sewing or not, the machine is out of well out of adjustment and it’s just a matter of eliminating possible causes.  Don’t worry, these machines will run great once you have the kinks worked out - and any old machine usually has a number of problems.  
 

I never seem to have any luck trying to adjust old check springs - there’s always a bend, twist, or break that makes it quite frustrating....the easy fix is just buy a five pack for $10.   Even if you only need one, it’s nice to not have to worry about damaging the one you’re installing.  Uwe has a great video on that.

Next I’d watch Uwe’s video on setting timing...that might be the cause of your skipped stitches.   It could also also be your timing is correct, but the point of the hook has too much of a gap between it and the needle. 

Before making any adjustments always start with a brand new needle - many machines have been adjusted to match a damaged/bent needle only to have new problems the first time the bent needle is changed to a good one.

Keep in mind the point of the hook should be come as close to the needle as possible, without touching it.    The larger the gap, the more likely it will skip a stitch, or break thread.   Also, the sharpness of the hook point is important - sharper hooks are more likely to properly reach behind the upper thread and pull it off the needle.

[bigsig11010]

I had to downsize the pics to upload sorry. Ive worked on correcting the threading and it seems to be doing better. Ill try to attach another pic. 

Can someone suggest which servo motor would work best with the seiko stw 8/ consew 225 please. 

[Handstitched]

G'Day,

I have the STW 28B , the twin needle version of yours ( but only use single needle, rhs) . Silly thing to suggest, but make sure the thread doesn't go behind the tensioners , done that a few times...oops  

I have mine anti-clockwise on the top tensioner and clockwise on the larger tensioner underneath , but you have your thread going through the guide on the right  a bit different to mine.  You have yours coming out the top.  I have my thread going ' down-up- down', then going anti clockwise on the top tensioner. ( hope that makes sense?)  I also by-passed the 'U spring' altogether, some on here might tell me off for that   

I  just went with what worked, it may not be the " correct " way of threading it, but it works . It did take a lot of fiddling about getting the tensions right  when I first got the machine, have to admit, but now it works fine.   They are a good strong machine  , when they run right   

Good luck   

HS

[bigsig11010]

I had to downsize the pics to get them to upload sorry.

how do I replace the check spring? I’m afraid to remove the tension part thinking some spring will pop out and be impossible for me to put back. 

 Could you please suggest a servo motor that will work well with the Seiko stw 8 please. 

[sandmanred]

One suggestion for your clutch motor speed control is to actually oil the clutch.  If you disassemble the clutch and generously wipe the clutch cork with sewing machine oil it will improve low speed control.  Just don't oil the brake side cork!  I've done this on my last few clutches and it improves low speed control significantly.

 

[Uwe]

If the check spring is broken, you can replace the entire tension unit. They’re readily available online or from our resident vendors. I recommend getting an original Seiko tension unit (or the Juki LU-562 tension unit, which should also fit your machine.) The super cheap Chinese versions on Ebay are not worth bothering with in my opinion (I ordered a few and decided not to use them).

 

Edited March 11, 2021 by Uwe

[MtlBiker]

17 hours ago, Uwe said:

@MtlBiker The part about going around the little pin is not quite right. Some YouTube video started this years ago and it’s being repeated all over the place ever since. I’ve not seen a single manufacturer manual that shows the thread path going around the pin. The pin is simply there to keep the tension discs from spinning. 

Geez, so I've been doing it wrong ever since I bought my 206RB-5 a few months ago.  And it was the DEALER (Eastern Canada distributor for Consew) who actually showed me and told me that the thread needed to go around that little pin.  And as far as I can tell, it's been working just fine that way.  (I had absolutely no experience with industrial machines at that point, nor really much general sewing experience.)  I guess I'll have to try without wrapping the thread around that pin.

 

 

[bigsig11010]

 Could you please suggest a servo motor that will work well with the Seiko stw 8 please. 

[Uwe]

Just about any servo motor will work with your machine. There’s dozens of topics about motors on this forum. Don’t be afraid to start a new topic for a new question, it keeps the topics targeted and easier to navigate.

One popular choice for servo motors is the “family sew” style motor with a small dial to adjust speed. It’s cheap and adequate. It’s available under various brands and model names from vendors on this forum and online (e.g. Consew Premier SM550, Family Sew FS550s, etc.) Available in many places, including here: https://www.tolindsewmach.com/motors.html

One of my personal favorites is this motor: https://store.keysew.com/sp-1100-npfl

Or pick a vendor from the ads in the header.

Please start a new topic if you have more questions about any particular motor. 

[bigsig11010]

Thanks to everyone who responded.

[MtlBiker]

20 hours ago, Uwe said:

@MtlBiker The part about going around the little pin is not quite right. Some YouTube video started this years ago and it’s being repeated all over the place ever since. I’ve not seen a single manufacturer manual that shows the thread path going around the pin. The pin is simply there to keep the tension discs from spinning. 

Uwe, I respect your vastly greater experience and knowledge than mine, but I really wonder about what you said regarding that pin.  You did say that there's wrong information being repeated all over the place and that's probably true.  But as I said, it was the Consew dealer who showed me how to thread my machine and I would expect that he knows how.  Plus I just checked a couple of Youtube videos about theading the 206RB and they also show and say to wrap the thread over that pin.  Here's one of the videos.

If you really think that shouldn't be done, I'll give it a test when I get home after work tonight.  I'd just hate to have to readjust all the tensions again since I've got everything running so well now.

[DonInReno]

9 hours ago, MtlBiker said:

Plus I just checked a couple of Youtube videos about theading the 206RB and they also show and say to wrap the thread over that pin.  Here's one of the videos.

This is the threading description from the Consew manual for the 206rb (rebranded Seiko) It makes no mention of passing thread over the pin.   Neither do a number of Singer manuals for machines that use the same tensioning setup.   Technically Uwe is correct and this is somewhat of a myth passed on, often with no idea why.

However, with many half truths there is probably a sliver of truth to it.  A fellow working in a garment factory once said they treated the factory recommended thread path as a starting point, and deviated from it when needed to increase tension.  Passing over the pin will definitely increase tension.    Maybe this allows less pressure on the tension disks and slightly longer time between disk changes. 

I see nothing wrong with the practice, the extra step just isn’t necessary, and it won’t make the machine sew better.

 

Edited March 12, 2021 by DonInReno

[327fed]

Constabulary was nice enough to post a utube for me in feb. on how to thread a Consew 225. I can’t seem to copy and paste the link but it is in the thread “maxing out Consew 225”. Might help.

[64poncho]

Here’s what happens when the thread goes around the pin!  This is what’s on the 206RB-1 I just bought. Don’t know how long it takes, but it will wear.

[RockyAussie]

The pin is there to keep the tension discs located and stop them moving around with the thread going through. If the tension discs were allowed to rotate then it is possible depending on the given set up that the tension applied could become erratic or the thread could be more likely to work its way out of the discs. Long and short ....the thread does not go over that pin.

[dikman]

Poncho, that is an impressive bit of cutting into the pin! An excellent example of why NOT to do it.

[DrmCa]

The rule of thumb for post-WWII machines is: if it's not chrome-plated, then do not wrap thread around it.