Screw and upper tension guide release

[mixmkr]

As noted in the pictures.....what does this set screw do? ...and is it related to the little pin that is suppose to plunge out and open the disks on the upper tension guide? 

Asking because the screw seems to have no effect and my upper tension isn't releasing at times, like I'm believing it should...  like with the presser feet up, etc.

[Uwe]

Rule #1 of sewing machines: don't turn a screw unless you know what it does

The first screw in your picture holds the check spring stud assembly (and the whole tension unit) in place. If you loosen it you can adjust the check spring tension. But it's really a set/lock screw, not an adjustment screw. (By the way, in your first picture the thread isn't pulled between the tension discs. Your thread tension will never work properly unless you pull the thread between the discs.)

The pin you're pointing at in the second picture pushes forward and causes the thread tension to be released. 

My video on replacing the thread tension release guide shows how that pin works:

 

Edited January 3, 2017 by Uwe

[mixmkr]

thx again Uwe,

Sorry about turning unknown screws!!.   Yes I saw it was just a set screw, but I'll always count rotations and such too (coming from working on paper folding machines, inserters...of the era)

and yes...the thread is just "laying" on the upper tension disks...  it's #138 PTFE thread...so I have to pull it down because the thread is so slippery and have a heavier than normal tension, it seems.  It seems that pin is not doing its' job, so will investigate further.

Your vid is an involved procedure, but shows what's happening.  I'll check it out more, but not sure I want to dismantle as much as you have done in the video!

I appreciate all the help as of recent.  thx so much

[mixmkr]

btw....Your vids give me the "courage" to wander into the forest!  ;-)

[Yetibelle]

13 hours ago, Uwe said:

Rule #1 of sewing machines: don't turn a screw unless you know what it does

The first screw in your picture holds the check spring stud assembly (and the whole tension unit) in place. If you loosen it you can adjust the check spring tension. But it's really a set/lock screw, not an adjustment screw. (By the way, in your first picture the thread isn't pulled between the tension discs. Your thread tension will never work properly unless you pull the thread between the discs.)

The pin you're pointing at in the second picture pushes forward and causes the thread tension to be released. 

My video on replacing the thread tension release guide shows how that pin works:

 

Rule 1.5:  Never turn a screw unless you have a magnet to catch it.  Or really good eyesight to locate it on the floor. 

[LumpenDoodle2]

I can vouch for rule 1.5, and would add the additional sub clause 1.5.3, that all floors, however tidy and uncluttered, will immediatly swallow any, and all screws/spindles/vital componant, whatever size or shape.   Never to be seen again, until you have just paid for a replacement.

As to Uwe's vid on changing broken tension release bits, I have successfully replaced the thread tension release guide on my Juki, no probs.   All due to this vid.

[brmax]

Sometimes just some adjustment can get it releasing correctly or like you want again. It looks like ya have a newer release assembly their.

I recall some have a pin in their parts that can get wore, though not sure on that one specific maybe singer I'm remembering.

Floyd

 

[mixmkr]

yeah...that's a newer upper tension assembly.  I switched back to my old one.  Went I started using PTFE thread, I was having huge problems and thought I'd get a new one.  Today has been horrible.  Tinkering all day while the sewing jobs pile up.  Machine is sewing like crap.  Will let a local sewing tech look at it... otherwise, I'm getting something new(er). 

[brmax]

What weight material are you running thru there this week. What seems like the main deal today, but anyway tomorrow is hump day so look ahead.

good day

Floyd

[mixmkr]

two layers of Sunbrella, a layer of Velcro, using Tenara #138 equivalent and tried needles from #14 up to 20...different bobbins..the usual drill

My problems is like Uwe noted in my one picture, the thread doesn't go between the tension disks....or stay there when sewing unless the tension is cranked... Then I'll break upper threads....  loosen it up, birds nest underneath.  The lighter Tenara works better...sometimes...

Hence asking about the Solarfix.  I can't use Dacron thread on my projects.  I almost bought a 1508 off Ebay today, but was gun shy.  Only $1150 for the shootin match.  Need to see what the venders here might do... and maybe take my LU562 in trade?   I can't afford a down day like today.   Yeah...tomorrow's another day... $0 for today...

[RockyAussie]

Just curious if you are using left twist thread. The picture is not clear enough to make out.

[Uwe]

That 1508 has the exact same tension unit as your 562 - it won't solve your slippery thread problems.

I'd experiment with thread path variations before giving up on the 562 and throwing money at something essentially identical.

This is how you normally thread the tension unit:

 

If your thread is too slippery to stay between the tension discs you can try this variation, looping the thread around the pin that keeps the tension discs from spinning:

 

If that still doesn't work you can rotate the thread guide down (loosen set screw, rotate, tighten) to bring the incoming thread closer and lower to the tension discs:

If your thread is still popping out from between the tension discs, then there's something else going on. Take the tensions discs out and inspect them . They should be flat on the inner part and only have and flare/curve on outer edge. 

 

Edited January 4, 2017 by Uwe

[RockyAussie]

Looks like Uwe just beat me but here see the link of the instruction manual where it shows the 3 part of threading. I must say that the looseness of thread before the tension disks looks quite bad.https://www.manualslib.com/manual/790496/Juki-Lu-562.html?page=8#manual

[brmax]

I was remembering you mentioned having to crank down the top tension, it looks pretty stout so for sure somethings going on in that area.

The solarfix is a ptfe, I realized also it feels tight in the tensioner top especially, and this stuff feels rough though and a design thing they may have picked up on to improve it. It was all really new to me and in 12 not really anything except tenara with very few people starting to use it that I heard in the marine trades.  With sunbrella honestly I don't see a need for 138, I wasn't saying anything because of sails and don't have a clue there, so with regular stuff I have to lean back and remember what I heard earlier on and that most pro's kept the use of 138 primarily because of the wear of other threads in the marine, salt and sun. When they started using the ptfe for boats or awnings they dropped to 92 size because the strength was there that they needed and not the issues from wear in sun.

But if it helps later on if you get some 92 size I use 19 needle and know a few to use 18 doing straights but I tried and just could pull it off consistent a mis here n there on the 08 at the time and so bumped up to 19. And try to keep everything same same for that stuff anywho.  Btw I can imagine the 138 Tenara thread size your using should I think use a 21-22 needle at least similar to poly or nylon eh?, ya have to help me understand that stuff a bit more.

Floyd

[Uwe]

By the way, the pin that goes through the machine to push the tension discs apart when you lift the foot is really optional and more of a convenience feature. The tension release pin should have no effect while sewing - in fact it shouldn't even be touching the back of the tension unit while sewing. Most machines sew just fine with that pin removed. The tension release pin just makes it easier to remove the material when you stop sewing, because you're not yanking on the thread while it's still has tension applied to it. 

[brmax]

That's a great point Uwe, and so must be few hangups in that mechanical lever stuff.

Floyd

[Uwe]

Sometimes that big tension release pin is just worn at the tips and not long enough anymore. I've made my own replacement pins from piano wire of same thickness and rounding/polishing both ends - worked beautifully.  That pin should slide through the body front to back very easily.

There's also a teeny-tiny pin inside the post that holds the tension discs. It often gets lost when people disassemble the tension unit. That pin is so tiny you hardly notice it when it makes its escape. Without that tiny pin, the tension release will not work at all.

The two tension disks are also not identical. One has a hole in the center, the other has a hole with a bar across the center. That center bar is what the tiny pin pushes against to separate the tension disks. If the disks are reversed, or both have a hole, or both have a bar, tension release will also not work at all.

[mixmkr]

you guys are a big help... will sleep on it for now.  Uwe...I have rotated my 3 hole threader, 90 degrees like you've said.   That helped, but the threader has a flat side, so the set screw doesn't really like trying to hold it other than a vertical position.  I'll keep experimenting.  Also realize the auto tensioner is just for pulling material out too.   Yeah...a conveinence.

Floyd...yeah...92 is probably ok, but 138 is a preference. ...ONLY because I see it a lot from other canvas guys.

and yes...left twist thread for sure... Don't think I own anything else except some mono or nylon junk.

 

I've learned a lot today... you guys are my only advice and what I can read... so it gets frustrating sometimes and I tinker more than I sew.  Need to make that a much better ratio

[dikman]

You could always file another flat on the threader shaft to secure it in a different position.