Newbie needs help getting a neglected Seiko Stw 8b up and running

[MaliMac]

Hi! I'm totally new to this machine- I usually sew for a sheepskin tannery on the isle of Skye in Scotland using a one thread overlocker, and at home using domestic machines. My workplace is shut indefinitely due to bleedin covid19, but they've given me loan of a Seiko Stw 8b to see if I can make use of it if and when I go back. I've looked at several grainy manuals online for it, and I think I've neeeaarrly got it going... Its been sitting untouched in an office for ages so I've oiled it, changed the needle- I'm worried I've made a mistake somewhere threading it, and also worried the timing might be out maybe- if it was one of my machines at home I would change the needle and rethread.. any advice would be amazing! I've attached pictures of the wonky stitching and my probably wonky threading. Cheers! 

[Matt S]

Hi Mac, welcome to the forum. Your place of work sounds fascinating, I'd love to hear more about it and maybe visit one day when this kerfuffle calms down.

Looks like your'e nearly there, but have too large a needle for your thread (or too skinny a thread for the needle). That's what's giving you the "spaghetti down a manhole" look, and probably your stitch skipping, since the thread needs to have some friction inside the hole to form a loop for the hook to grab.

What are you intending to sew? The largest thread you'd want to put through a STW-8 with any regularity is TKT20/V138, which is available in nylon, polyester and various polycotton mixes. For reference, the gold topstitch thread on a pair of jeans is usually a soft-laid TKT30 polycotton (one size smaller than TKT20), and 18/3 linen thread is one size larger (TKT13).

A size nm140 needle is a good fit for that TKT20 thread. The STW-8 uses class 135x16 leedeles for leather, vinyl and other things that need a cutting point and 135x17 for cloth. There are different point styles for 135x16 needles, which give different effects however the LR type (which gives an even, slanted stitch) is probably most popular. This chart is very handy.

[Uwe]

Your bobbin threading doesn’t look right, your bobbin thread goes over the edge of the bobbin case. You need to pull the bobbin thread into the slot of the bobbin case ( near the 4 o’clock position) and under the tension spring. Your bobbin threading is likely to cause skipped stitches and other issues.

On the top thread tension unit, don’t run the thread around pin on the edge of the tension disks - several youtubers show this threading for unknown reason, but not a single manual that I’ve read shows that.

Post some detail photos of the check spring area, it’s hard to tell exactly what’s going on there.

As for timing, your machine is a very close relative of a Consew 225. You can use this hook timing video as a guide: 

 

 

 

 

Edited May 27, 2020 by Uwe

[Handstitched]

G'Day MaliMac, and welcome to the forum and welcome to  a fellow Seiko  STW ....' recipient' ?

Isle of Skye ? I have 'post card pictures' in my head. Anything like the Shetlands? I'm an ex- Suffolk man myself . 

I've always used M40 threads on my STW, although I haven't tried other threads, but it works fine. I also had this similar issue when I first  got this machine  many years ago.  I was cursing like a trooper for about an hour trying to get this thing working because it kept missing stitches...... until I worked out what the insy winsy screw was for on the side of the shuttle, just like Uwe said , after that, it worked great. I couldn't stop myself  sewing after that, I was so happy I went and had a beer    I also worked out what those shiny buttons in the centre are for too.  Looks like you have it threaded correctly .  Call me biased, but they are a good reliable machine. 

HS

 

 

[MaliMac]

Thank you all for the replies. And sorry for my delayed response - I've been fiddling with it a bit more and trying to find a good window of time in which the kids are otherwise occupied! I get you about the needle/thread size @Matt S - the needle that was installed in it and the similar ones that came with it arent in a box unfortunately so I cant see what size they are, but in addition to being big they're a bit longer than the other needles that came with it.. having watched that video @Uwe I think my timing is ok, but it seems to need the longer needle for the hook to catch it at all. All of the needles I've used with my other machines have been the same length so this is also new to me- which number on the box refers to the length of the needle? @Uwe and @Handstitched I definitely think part of the issue is my bobbin threading- the thread is just not going behind the tension spring- I've tried loosening the tension screw and it doesn't seem to help. Should I take the shuttle out and have a look? Not that I know how to do that! I've attached pictures of my threading @Uwe and I think I've corrected the pin issue. I'm also going to try to attach a link to a video of my bobbin when the plate is off to see if it looks normal.

@Matt S I'm really just trying to learn more - pre furlough I was about to go on a leather bag making course in england, darnnit, but now I'm trying to use the time to learn as much as I can. I've got some nice soft chrome tan leather, about 2mm thick which I want to try to make a really simple bag, just for myself. I have a friend who makes leather sheaths for her brother, who in turn makes beautiful knives, and she has ideas of things she'd be able to do with the machine up and running too. I work at a tannery called Skyeskyns, usually making rugs and cushions, that kind of thing. 

@Handstitched even though I cant get the bloody thing going yet, I already love it!! It's like a tractor!

Skye is much more mountainous and green than Shetland actually, and today it is brilliant sunshine and very picture postcard.

 

Thanks again for your help!

Edited May 29, 2020 by MaliMac

[MaliMac]

https://www.facebook.com/mali.messent/videos/10158113387811005/

 

Hopefully you can see that - does this all look normal?

[nylonRigging]

3 hours ago, MaliMac said:

https://www.facebook.com/mali.messent/videos/10158113387811005/

 

Hopefully you can see that - does this all look normal?

I opened your link . ( If this what talking about ? ) .  The basket needs held for timing, You got to get a Needle Plate to hold the bobbin assembly in place from freely spinning . After than, then you can start to see if there are problems .

[MaliMac]

17 minutes ago, nylonRigging said:

I opened your link . ( If this what talking about ? ) .  The basket needs held for timing, You got to get a Needle Plate to hold the bobbin assembly in place from freely spinning . After than, then you can start to see if there are problems .

Sorry, I didnt make that clear in my previous post, I have got a needle plate that holds it all in place, but I am totally green to this type of machine so wanted to make sure it was supposed to spin freely like that without the plate. Having watched that previous video I think my timing is ok, but definitely my bobbin threading is a bit whack! 

[Uwe]

Your machine uses system 135x17 (fabric) or 135x16 (leather) needles. Neither of your needle packs in the photo are the correct needle system. It’s probably best to just discard all the needles that came with the machine, seriously. None of the numbers on the package tell you the length, sorry! Needle systems are a science in itself. Search Ebay for “135x16 needles” or contact one of our resident vendors.

Buy some of the correct needles and then adjust the needle bar height to get the needle position and timing right, as shown in the video above.

Use the Consew 226 manual as a reference, courtesy of @Gregg From Keystone Sewing. Seiko built the machines and sold them under the Consew brand back then. 

Edited May 30, 2020 by Uwe

[Handstitched]

@MaliMac I did remove the shuttle to get to the tension screw, with a bobbin of thread in to get adjusted right.. I tried adjusting it while it was in , but  I found it a bit  awkward , for me anyway,  and I  risked damaging the screw, and with my ' fat  fumble fingers'  it was even more awkward. Others may find it easy to adjust.  I also magnetised my screw driver so I didn't lose any tiny screws removing the shuttle.  

[MaliMac]

4 hours ago, Handstitched said:

@MaliMac I did remove the shuttle to get to the tension screw, with a bobbin of thread in to get adjusted right.. I tried adjusting it while it was in , but  I found it a bit  awkward , for me anyway,  and I  risked damaging the screw, and with my ' fat  fumble fingers'  it was even more awkward. Others may find it easy to adjust.  I also magnetised my screw driver so I didn't lose any tiny screws removing the shuttle.  

I took those weeny screws out but still couldn't get the shuttle out, how do you remove it? I had a fridge magnet with them preciously stuck!

[nylonRigging]

10 hours ago, MaliMac said:

I took those weeny screws out but still couldn't get the shuttle out, how do you remove it? I had a fridge magnet with them preciously stuck!

it will slide strait-up and out, as it is all one unit on the shaft . look underside for a set-screw holding shaft position . should be very similar to this old Singer 112 bobbin assembly .

-

-

[Uwe]

Removing the entire hook to adjust bobbin tension seems rather excessive. I'd go buy a suitable screw driver that lets you turn that bobbin tension screw without having to remove anything. Those little screwdrivers you can buy as part od a eyeglass repair kit at most drug stores work really well.

[Gregg From Keystone Sewing]

Hirose MFG # HSH-12-40 is for Singer model 112W140 and maybe others, Singer part number for the hook base with bobbin case complete is 236083.

The hook driving shaft has a V ditch where the driving pinion gear set screw would fall on to, and should have a ball point screw.  Some gears have an S stamped next to this set screw hole.  Taking the hook out of the machine is one way to do it, but if you turn the hand wheel over in a sewing motion, the first set screw that comes to you can be removed, and the second set screw can be tight as to not disrupt the timing, and then we can look down into the hole for a V ditch, a flash light helps if you have even good lighting.  

Edited May 31, 2020 by Gregg From Keystone Sewing

[nylonRigging]

3 hours ago, Uwe said:

Removing the entire hook to adjust bobbin tension seems rather excessive. I'd go buy a suitable screw driver that lets you turn that bobbin tension screw without having to remove anything. Those little screwdrivers you can buy as part od a eyeglass repair kit at most drug stores work really well.

LOL.... Well he was asking about how/removing shuttle/hook ????  , easy to pull it out and remove replace what you want and put back .

( MaliMac said:  ) quote: ..." but still couldn't get the shuttle out, how do you remove it ? "

And If nothing else .. It always good for him to see what the thing is and looks like,  he is actually monkey wrenching on .

.

Edited May 31, 2020 by nylonRigging

[MaliMac]

Thanks for all the replies, I'm just waiting on needles and thread now.

[DiverMike]

I am having a related but different problem with the Seiko I have just got. The bobbin thread is creating a loop and when I hand crank to bring that thread up to the top to start sewing I can't pull it up - its as if it is jammed.  Then if I do another revolution of the hand crank the top thread which have now been caught by the bobbin thread either snaps or creates a loop unde the feed dog.  I've made a video to show how I am loading the bobbin as I think its the same as the guide above.  I fugure I must be doing somehting wrong as it worked fine when the seller demonstrated it to me

https://www.youtube.com/watch?v=GnF1HWy_HhQ

I knew getting an industrial machine would be a bit of a learning curve but I was hoping I could at least get some stitches out ot it :-( 

[Uwe]

You’re holding the wrong thread. In your video you’re holding the bobbin thread and the top thread gets pulled into the machine. Instead, hold the top thread  and pull it tight after it gets wrapped around the hook - that pulls the bobbin thread up through the feed dog and to the top.

[DiverMike]

Thank you - all sorted.  Now to sort the tension out...

[DonInReno]

On 6/17/2023 at 9:12 AM, DiverMike said:

Thank you - all sorted.  Now to sort the tension out...

Old machines have tension issues more often than not - at least with my luck - a simple check I started doing with any machine I’m not used to sewing with is to thread the tensioner and manually pull thread a little while cranking the tension screw all the way out and all the way in, as well as while lifting the presser foot all the way to check the operation of the thread release.   Even brand new tension disks can be the wrong shape and not function correctly.