# Frustrated with pull-outs (false starts), and too frequent shredding (fraying, thread breaks)



## Stan Hoover (Jan 28, 2009)

I have checked all the usual suspects but am still getting false starts after a trim or color change. Here are the details: 

Tajima TFHX-IIC1504 (4 heads)
1) Occasional pull-outs seem to be random

2) Shreds (frayed thread, or thread breaks) seem to be random

3) Some needles replaced, angles checked with 10X Loupe

4) Picker adjustments were made, without much improvement.

5) Rotary hooks to needle scarf clearance falls between .004" and .012". (Verified to my satisfaction, using flexible feeler guages, favoring the lower end of that range.) Nicks and scratches on all hooks have been removed, and 1 hook was replaced due to a dull point.

6) My ThreadTensions are clearly questionable.... much more questionable than my observations on the first 5 points. IN FACT, HEAD #2 IS COMPLETELY WHACKY IN REGARD TO TENSIONS. IT WON'T SEW DECENT "THIRDS" unless the bobbin tension is turned way down. Down low enough to nearly freefall, using the drop test.

Perhaps the missed-starts and the shreds are related, but I suspect not. 

To review and clarify my questions,

*Why do I get so many pull outs after color changes?*

*What can cause shreds and thread breaks on a "correctly" timed hook?*

*Why would #2 head need goofy tensions to sew thirds, when 1,3 and 4 are reasonable and predictable?*

I'm interested in anyone's thoughts on the subject.

Thanks!
Stan

P.S. _(Heads 1,3 and 4 bobbins are measured at 115-140nM on the Towa Bobbin Guage TM-1 which translates to 12-15Grams, and 110-120Grams on the upper thread tensions measured with a Cheapo China stick guage. Head #2 needs only 6-8 grams--nearly freefalling!-- in order to get decent "thirds" using the same upper tensions. Swapping bobbin cases didn't seem to matter, although moving back to coats bobbins from magna glides changed things to some degree.) Ping me offline for a phone number to call if you like, and if it might be helpful. I have NOT checked needle depth yet, nor have I synched the heads._


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## AndTees (Jul 6, 2009)

On the strange head, take a very careful look at the thread path, clean and correctly threaded. I have seen strange problems as a result of having a thread looped around a wire-guide, split by a wire-guide, twisted in the take-up area, a maladjusted spring and have had more than one bad spool of thread that simply can't be correctly adjusted (changed the thread and problems went away).


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## oldkush (Jun 25, 2007)

*>> Why do I get so many pull outs after color changes?*

Possible causes for your pull outs ....
- top thread tensions too high. Make sure your thread tensions are correct. Start with a properly tensioned bobbin, then set top thread tensions.
- trim length too short. Assuming that your picker is not bent/misaligned, increase thread tension through your control panel
- machine is going to full stitch speed too quickly when starting new color. Increase inching stitches using control panel.
- start tie-in stitches are turned off. Through the machines control panel, make sure that tie stitches are on for both start and end.
- design does not contain start lock-in stitching. Edit design so that there are lock in stitches for the start of each color plus where ever possible, start a color on existing stitches [to give the thread more "grip"].
- material being stitched may be very thin / light and extra stabilization may help


*What can cause shreds and thread breaks on a "correctly" timed hook?*

Thread shredding and breakage is most often caused by ...
- a rough spot or burr somewhere along the thread path. Check thread path and remove any rough spots with emery / crocus cloth.
- old thread [especially if it is rayon]. If this is the problem, it may help to store thread in a freezer. This will add moisture to the thread and give it some extra life.
- a rough spot on the rotary hool. These can be so small that they are difficult to see by eye. Often the easiest way to detect a rough spot will be by running the tip of your finger nail over the surface feeling for a slight snag.
- top tensions too tight [especially with rayon thread].

*Why would #2 head need goofy tensions to sew thirds, when 1,3 and 4 are reasonable and predictable?

*The fact that you can only get a decent sew out by reducing your bobbin tension more that it should be would suggest that your top thread tensions on that head are too loose ..... probably because your tensions disks / thread path on head 2 are in need of a real good cleaning [use alcohol and q-tip or pipe cleaner]. Also check to see that the thread path is correct.



Bob


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## oldkush (Jun 25, 2007)

Should also have mentioned that you may benefit from the Tajima group at

TajimaPlus : Tajima Owners Group

I am there and so are a lot of other Tajima [plus other machine brand] owners. 

Bob


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## stitcherlady (Jan 20, 2009)

Hi its been along time since I had my old tajima 1501 but I used to have those false start problems and it was that the little picker coming down to pick up the thread after the trim was actually cutting the thread on its way down making it very short and not enough to pick up and restart. Seems that I may have filed it some and put tape on it to keep it from cutting the thread. Hope this is helpful.


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## LUV DEM TIGERS (Jul 25, 2008)

I have a Tajima Neo 2 and every once in a blue moon I will have a thread get out from underneath the very top thread tension disk at the thread stand right before it enters the thread tubes. Don't know how it happens, but it does.


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## LUV DEM TIGERS (Jul 25, 2008)

I have also had times where my thread tension was too high or too low and couldn't get it to change no matter what I did. I would visually check the thread path. I couldn't find anything. Then out of frustration, I would completely rethread and the problem would fix itself. Weird.


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## Stan Hoover (Jan 28, 2009)

Wow. This forum is a tremendous help! Thanks to everyone who has replied. I am just beginning to understand how this machine works but have already done many (if not most) of the procedures in this thread.

I have NOT, however, tried to adjust the thread trim knives. This area is highly suspect in my mind, because I have observed the "wiper" pulling so hard on the "tails" that I often hear a TEARING sound. I read that Poor Trimming could cause poor restarts. (And yes the pickers where all pretty whacked out. Fixed...)

The goofy tension requirements on head 2 are stabilized, if not improved.

For those with the Towa Bobbin Tension Guage" 
1) How fast do you draw out the thread? and

2) what are your typical Values?

Hirsch advised me to aim for 20-25 Grams (or 200 to 250 nM) but that seems WAY to high to me.


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## tfalk (Apr 3, 2008)

Stan, have you tried changing the inching speed? We had a LOT of trouble with our SWF when we first got it, every color change wouldn't start stitching... I slowed down the inching speed and there is another setting for how many stitches before it increases speed, I think I changed that to 8 or 10 and it did wonders for our machine...


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## LUV DEM TIGERS (Jul 25, 2008)

Also, if you get "false" thread breaks where it is really stitching when you first start but it registers a thread break, you can adjust the number of stitches before it registers a thread break. If it is set for 3, then it will sew three stitches and if the thread sensor disk haven't turned enough, it will register a thread break. If you change it to 10, then it will go 10 stitches before registering a thread break. Thus it is less like to register a false thread break.


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## Stan Hoover (Jan 28, 2009)

tfalk said:


> Stan, have you tried changing the inching speed? We had a LOT of trouble with our SWF when we first got it, every color change wouldn't start stitching... I slowed down the inching speed and there is another setting for how many stitches before it increases speed, I think I changed that to 8 or 10 and it did wonders for our machine...


Never heard of that. I did however, change the _number_ on inching stitches from 4 to 6. At least I thought that was what I was changing. I just did what the Hirsch tech was telling me to do while I had him on the phone. 

Anyhow, changing the inching value from 4 to 6 may have helped some...

Thanks for the reply. I'll look into inching _speed_, since you brought it up. But I really hate looking for stuff in the manual. I apparently don't speak Janglish. =D) 

Stan


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## Stan Hoover (Jan 28, 2009)

LUV DEM TIGERS said:


> Also, if you get "false" thread breaks where it is really stitching when you first start but it registers a thread break, you can adjust the number of stitches before it registers a thread break. If it is set for 3, then it will sew three stitches and if the thread sensor disk haven't turned enough, it will register a thread break. If you change it to 10, then it will go 10 stitches before registering a thread break. Thus it is less like to register a false thread break.


I am not aware of this setting. I'll look to see if I can find out what the setting is on my machine.

Thanks!

Stan


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## Stan Hoover (Jan 28, 2009)

LUV DEM TIGERS said:


> I have a Tajima Neo 2 and every once in a blue moon I will have a thread get out from underneath the very top thread tension disk at the thread stand right before it enters the thread tubes. Don't know how it happens, but it does.


Interestingly, this happened today! I had seen this only once before, but as I said in an eariler post, I am not one of the "operators", I am the owner--and repairman wannabe. But our Sr. operator had never seen this in almost 2 years of sewing. She was impressed when I pointed out the problem, and fixed it. HA! (Just dumb luck, really.)

I did uncover a potential issue early this morning, before we started production. I drove in to work in the wee hours. to poke around in the trimming area, to see what I might uncover. I found a knife that isn't making the kind of contact I'd like. My Tajima has a 3 component trimmer: A movable knife, and fixed knife and and a lightweight sheetmetal....um....aid of some kind that contacts the underside of the moving blade. It is roughly parallel to the cutting edge of the fixed knife, only lower, flexible and very very lightweight.

Well, I coated the moving blade with magic marker, my country boy substitute for Prussian Blue (machinist's blue) and was surprised to see head #2's trimming is suspect. It scraped the leftmost edge of the moving knife nice and clean (starting midway) but the rightmost edge of the blade was clearly less cleaned.

Ideally, and this is _hard_ to describe on a keyboard, I would like to see the moveable blade moved UPwards maybe .0005" or even .001" --because I was unable to tip the fixed blade in any manner that "cleaned" the marker the way I wanted. I think I could "clean" both cutting edges of the "V" shaped moveable cutter with the fixed knife...IF I can raise it up just a skoshe, then tip the fixed knife up a wee bit on the left end. (Whew...)

That fixed knife appears to be engineered to flex just a bit, no doubt in concert with the flexing of the moving knife, in order to maintain an acceptable scraping tension during the actual cut. This begs a fairly technical question: *Where is the best point along the machined section of the movable knife, for the contact of the fixed blade to begin?* (Closer to the leading edge, I'd imagine, but maybe that would accelerate wear, favoring a clean cut every time over life expectancy.) 

This machine is certainly an example of fine engineering. Somebody hangin' around it oughta really get a clue how to wrench on it. 

That would be me. And so far, I just barely know enough to be dangerous.


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## designconcepts (Jul 30, 2009)

Stan Hoover said:


> This machine is certainly an example of fine engineering. Somebody hangin' around it oughta really get a clue how to wrench on it.


So true.......I stand back and watch and am just amazed.

I don't mean to hijack the thread, but can I insert a quick question? I have the VERY same problems Stan's having (and some.....). But what happens when the thread still doesn't catch after several "inching stitches"? I've set my machine to 6-8 so it should catch, and even held the start button to creep through. Every time though it just inserts then pops back out. Enough and it's popped out of the needle entirely. 

This may have been mentioned before, but I kind of got lost in it. What [other] setting needs to be changed? 
Thanks!


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## Stan Hoover (Jan 28, 2009)

designconcepts said:


> So true.......I stand back and watch and am just amazed.
> 
> I don't mean to hijack the thread, but can I insert a quick question? I have the VERY same problems Stan's having (and some.....). But what happens when the thread still doesn't catch after several "inching stitches"? I've set my machine to 6-8 so it should catch, and even held the start button to creep through. Every time though it just inserts then pops back out. Enough and it's popped out of the needle entirely.
> 
> ...


I'm just beginning to understand this stuff and probably should just let someone else respond, but have you timed your rotary hook(s)? It has helped us tremendously to do that. Our missed stitches or false starts (or pull-outs) are random now, and far less common. So I know that was a big part of our problems. We are still experiencing some issues, but things are getting better as I understand more.

Stan


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## tfalk (Apr 3, 2008)

Having just timed a hook for the first time yesterday, I have to say, I was amazed at just how little room/duration there is for a stitch to work correctly... These are really amazing pieces of equipment if you sit back and watch them...

And a warning for people... Like racecars, be very watchful of pieces falling off the machine... We had a small black piece of what looked like plastic kick out of the machine about 2 weeks ago. It kept on stitching but we started having more and more errors, finally resulting in overload errors and the machine totally jambed up. Tech came out and found that the small bumper that prevents the reciprocator from over-rotating had broken off... Well, at least I now know how to time a hook and replace a reciprocator...


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## designconcepts (Jul 30, 2009)

Timed it PROPERLY today as a matter of fact. 

Had a broke rotary hook (don't ask!), and after replacing it, I never took the time to time it properly -- didn't KNOW how to time it at the time.
Just received a 'maintenance' training video today. I would recommend this to anybody starting. It definitely gave me a better idea of the machine. 

Still have a lot of things to learn, but I think I learn something new every time I turn the thing on. Thanks for the suggestion Stan!


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## Stan Hoover (Jan 28, 2009)

designconcepts said:


> Timed it PROPERLY today as a matter of fact.
> 
> Had a broke rotary hook (don't ask!), and after replacing it, I never took the time to time it properly -- didn't KNOW how to time it at the time.
> Just received a 'maintenance' training video today. I would recommend this to anybody starting. It definitely gave me a better idea of the machine.
> ...


You are most welcome. Just passing along suggestions made to me, which worked. Just don't confuse me with an expert. I'm green all the way to the core. =o/ 

What video did you get? I bought one called just called Embroidery Training Video (I think). It has lots of nuggets buried in it.


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## designconcepts (Jul 30, 2009)

As am I!!
*www.EmbroideryTrainingVideos.com* is the link. I have the "Universal Repair DVD", which has a LOT more than just repairs. Hopefully I won't have to actually apply that kink of knowledge such as replacing motors but it gives me a much better idea of how the machine actually runs and is put together.


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## tfalk (Apr 3, 2008)

Those training videos also saved me a couple of times... John Dunbar is the SWF trainer in Shrewsbury NJ, very helpful...


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## Flint54 (Oct 16, 2008)

You would be surprised at how small of a burr, nick etc. on a rotary hook is needed to upset and or cause problems. But you need to know exactly how to time this part in your machine. If you do not form a perfect stitch you will have many problems. Contact your Tech Support for proper procedures. All machines are similar just not exactly the same. In general I set our hooks to no more than .003 gap from the needle scarf, with the needle lowered in the needle bar the hook will actually contact the full diameter needle. If the hook has no defects and is properly timed then see the item below! I'll bet that replacing this part or removing it and doing a complete polish on the tab area will cure your immediate problem until you get a replacement. 

One other area to keep a sharp eye on is the "Rotary Hook Support". This bridging piece has a tab on it that mates with the slot in the Rotary Hook and prevents the bobbin/case from rotating. The upper thread when picked up by the hook actually slides through this area and in so doing puts a lot of wear on the tab of the "Rotary Hook Support". This wear creates a sharp edge on this tab that frays, tears, and even cuts the upper thread. You will tear your hair out looking for other problems, check out this piece and make sure that you order a couple for your "NEED ON HAND" parts bin, this is a must have spare part. When you order one look at how highly polished this tab is and make sure that the part in you machine is the same!!!


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## Stan Hoover (Jan 28, 2009)

Flint54 said:


> You would be surprised at how small of a burr, nick etc. on a rotary hook is needed... In general I set our hooks to no more than .003 gap... If the hook has no defects and is properly timed then see the item below!


Didn't see the "item" to which you refer. Perhaps you meant checking the rotary hook support.

And I am setting the hooks between 4 and 12 thousandths. If I go tighter than .004", I can hear the needles tick sometimes on the hooks. (I *think* that's what I'm hearing at least.)



Flint54 said:


> One other area to keep a sharp eye on is the "Rotary Hook Support". This bridging piece has a tab on it that mates with the slot in the Rotary Hook and prevents the bobbin/case from rotating. The upper thread when picked up by the hook actually slides through this area...


This hook support (Tajima techs call it the Basket Support-if I remember right) is a possibility. I observed that theses are HIGHLY polished and now I know why. Thanks for that! I will look at these for burrs, etc. 

I believe my hooks are OK, since the machine is running MUCH MUCH better. I have checked them throughly, and found at least one scratch or nick on all four hooks! I worked them all, first with 120, and then 150 grit Emery Cloth, and then finished with 800 Crocus. 

I was still missing stitches right after a trim--causing pullouts, even though the timing, I believe, was corrected. I then bought a NEW HOOK, and observed the shape of the point *in detail.* 

Then with my dremel, I ever so cautiously _reshaped_ one of the worst hooks in my arsenal which was no good anyhow. WHAT A DIFFERENCE it made! 

I then did 2 more hooks which when compared to the new one, were clearly worn on the very tip. They all work MUCH better than before.

You surely can't do this more than once in the lifetime of the hook, or the timing would be hopeless. And I honestly cannot recommend this to normal folke. I am extremely nearsighted, and without corrective lenses I have very fine close vision. 50 feet away, I can't tell a man from a woman with my glasses off, but if you get a splinter, I'm your guy!

Anyhow, I am still seeing pull-outs on restarting after a trim, or color change--maybe a handful or and handful and a half, per day. Not enough to warrant a major overhaul, but enough to be aggrivating and time consuming. Shredding in much better.

Stan


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## Flint54 (Oct 16, 2008)

Another thing to check on your pull outs is, Are you using a basic or line lock stitch? If you are not using a basic then you are getting a line of stitches, if so and you have a low inching count/setting then when the machine speeds up your stitches will pull out very easily. A basic lock will do the bow tie and prevent this from being a problem. Just another idea for you to check.

Also I have re-ground a couple of hook points, only on the single head being that the setting will be a bit off from the others if you do it on a multi. As far as polishing, head to Lowe's or your local builders supply and get a few sheets of 600/800 & 1000 grit paper. Start with the 600 if you have a noticeable nick and work up to the 1000, for general I just use the 800, as it wears it acts like the 1000.


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## Stan Hoover (Jan 28, 2009)

Flint54 said:


> Another thing to check on your pull outs is, Are you using a basic or line lock stitch?...


I didn't know it would matter. Actually I have no idea. Would my operators know? I'll check about that, but I did turn the inching stitches up from 4 to 6. (I think...)




Flint54 said:


> Also I have re-ground a couple of hook points, only on the single head being that the setting will be a bit off from the others if you do it on a multi.


I thought the INDVIDUAL hook timing was paramount. I didn't think about the sync factor to which you allude. How could that play out? The girls have been sewing for a couple of days or more, since I did that. With better results. MUCH better.



Flint54 said:


> As far as polishing, head to Lowe's or your local builders supply and get a few sheets of 600/800 & 1000 grit paper. Start with the 600 if you have a noticeable nick and work up to the 1000, for general I just use the 800, as it wears it acts like the 1000.


Like automotive wet or dry? I guess so because I am unaware of that fine a grit in papers not intended for automotive. I was using Emery, because in my mind, it would be "softer". Like garnet paper VS silicone carbide. If you're using the auto finish paper and having good success, I'll just switch to that. The finer grit selection would seem desirable.

Thanks!


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## Flint54 (Oct 16, 2008)

According to the maintenance info on multi head machines that I work on (Tajima Specific) there are certain degree marks/positions that items are required to line up. As an X machinist & aircraft mechanic I don't know how much re-shaping one or more hooks would effect the overall performance of a multi head. At the same time I am not in a position that I need to know nor do I want to experiment with the concept due to the possibilities. I'll keep with new replacements as needed. So far in 3 years of operation we have only had to replace 2 hook assemblies out of 3 machines. All the rest have only required polishing.

The fine grit paper as you correctly surmised is the black wet dry paper. Any of the three grits will work, 600 is really all that is needed, when you use it the paper/grit wears quickly and will polish very nicely. One trick is to rub the 600 over the edge of a piece of steel bar, this will break away many of the sharper grains. Emery is messy and if you get oil/fluid on it you will create an abrasive paste that sticks where you don't want it to be. The adhesive also degrades and abrasive grains fall off the backing. 

Remember to ALWAYS clean your rotary hooks with a cleaner after polishing to get rid of any abrasive that can become trapped in the guide area, I use brake cleaner. After cleaning insure that you properly lubricate the hook to prevent galling on startup once it is reinstalled.


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## Stan Hoover (Jan 28, 2009)

Flint54 said:


> ...I work on (Tajima Specific) there are certain degree marks/positions that items are required to line up. As an X machinist & aircraft mechanic I don't know how much re-shaping one or more hooks would effect the overall performance of a multi head.


I probably fouled up then, at least in theory. The detrimental effect that a fraction of a degree change in the hook geometry was far surpassed by the restored shape of the offending hook--picking up the loop better. I won't attempt it in the future. I was just lucky in this case, I guess.



Flint54 said:


> The fine grit paper as you correctly surmised is the black wet dry paper. Any of the three grits will work, 600 is really all that is needed, when you use it the paper/grit wears quickly and will polish very nicely. One trick is to rub the 600 over the edge of a piece of steel bar, this will break away many of the sharper grains...


Steel bar idea is good. I can see how that would knock off the "extremes"



Flint54 said:


> Remember to ALWAYS clean your rotary hooks with a cleaner after polishing to get rid of any abrasive that can become trapped in the guide area, I use brake cleaner. After cleaning insure that you properly lubricate the hook to prevent galling on startup once it is reinstalled.


Yep. I Always do. I've been using some carb cleaner, although the brake cleaner is a better idea. It seems to flash off better, at least the brands I've used.

Good stuff, Bob! I appreciate the thoughtful replies. Oh, and by the way, It's pretty pleasant in the sewing room. The shrieks and whining by the girls has been replaced by the comforting sounds of embroidery in progress.

Stan


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