false bobbin breaks (Amaya XT)

[Gini]

I have had a consistent problem with frequent false bobbin breaks. I have turned off the bobbin thread sensor under settings and I run the machine without it. I have done this since I got the machine new 6 months ago. Of course, the problem is that when the bobbin runs out I get a mess of tangld top thread and need to remove the bunched top thread, back up the design and start back up which is a pain. Does the bobbin sensor work on most XTs? What can be done to get it to work better?

[Linus]

Gini,

Have you tried a different bobbin case? Have you tried adjusting the the bobbin tension? Does this happen on all designs or just particular ones?

Just somethings to think about.

Linus

[Jason]

Gini, Linus is right. Generally this is a tension problem. It will happens from time to time depending on design. Try using let tension and re-running the design. If you are running hats it will happen even more. I usually disable if I am getting a lot of these messages. You just need to get into a good habit of keeping an eye on your bobbin all the time. I check mine every 3-4 runs depending on design.

Jason

[Buy The Stitch]

Gini,

In addition to the tension, I occaisionally forget to reset my presser foot height which causes false thread/ bobbin breaks. You might also check to see that the thread path is correct, and that it goes around the sensor bar correctly.

[Alicante]

Where do you reset the pressure foot height on the XT?
Lots of good info here on the false thread break issue. Had to turn it off to embroider lately.
The designs sewed out fine, but would like to solve the issue as it's a handy gadget!

[signman]

Look at the front of the needle casing, reach around the LEFT side and you'll find the round cog wheel that adjusts the pressor foot up or down.
Always do this BEFORE SEWING...never during a sewout!

[Rod or Sharon]

Hi Dee,

As Roland indicates it is found on the left side of the machine and behind the needlecase. If you move the needle case to needle 16 , the round cog wheel is quite visible.

To VISUALLY see the presser foot move while adjusting it, you MUST go into Maintenance, Head Timing and Bottom Center. This puts the Cam Follower in the right position on the Presser Foot Cam for it to be able to raise and lower it. This is the proper way to set the Presser Foot.

Now having said that, I would venture to say that 90+ percent of your sewing will be done with the presser foot all the way down and up 1 or 2 clicks. I personally have not had to go above 4 clicks up and that was on a very heavy Carhart jacket.

If you don't care to visually see it move, then just rotate the cog wheel COUNTER-CLOCK-WISE until it stops and turn it back CLOCK WISE 1 or 2 clicks, you will be right where you need to be for most of your sewing. A key to just how high it needs to go is the type of material being sewing on. If the Presser Foot is leaving a mark or footprint on velour, velvet, leather, etc...then you may need to raise it and slow down the speed to help prevent flagging.

The Presser Foots soul purpose in life is to hold the material down long enough for the needle to be able to break free from the material. If the Presser Foot is too high, then the material will stick to the needle and be raised with it....this is called flagging. Throw this in with loose hooping , large hoops that are bouncing up and down, adhesive sprays, sticky backing, etc....and you will pull you hair out with fraying and false or real thread breaking....

Rod Springer
Amaya Tech & Trainer

[Alicante]

Great, I am adding this to my maintenance info and try adjusting the pressure foot because I am still not able to sew with thread break sensors on. Am using Melco round 5" hoop and sailcloth fabric with medium tear away. But have tried on felt and broadcloth and the sensors beep the same.

Sews out fine in any case. Just like to have everything working.

I have tried the following without success:

Changed the bobbin holder, worked for one sewout then back to bleeping every 5 stitches.

Adjusted the bobbin tension screw.

Reset thread tension, tails etc to default

Set it to auto-feed...

set it standard feed 1 in this case.

rotating the thread sensor bar gently but repeatedly.

sewed a standard simple Melco design instead of my own.

removed the bobbin case cover and blew compressed air throughout base arm. and checked for threads.

checked minimum thread feed setting, it's at 1.

Got the dehumidifier going closer to the machine. It's pretty humid here.

Changed needles. Same bleeping whatever needle being used.

Made sure hooped fabric is taut.

***The machine sews fine with the thread sensors off. ****
The question is how do I fix the disfunction of the the thread sensor. I'm working on it. [img]tongue.gif[/img]

[Alicante]

Oh yes and I checked the thread paths. All are correct.

[The Embroidery Authority - OLD]

Dee,
Along with all the other information that has been mentioned, I'm thinking the lower thread feed limit might be set too high. Make sure this is on the factory default of 1.

Also, are you sewing using tear-a-way backing or possibly only one layer of cut-a-way backing? If so, if your columns are too narrow or your stitch lengths are too short, then you might be cutting holes in the backing as you sew which can trip up the bobbin sensor. Make sure you have your minimum column widths set no less than 10-12 pts. in Design Shop and be sure to use a minimum of two layers of cutaway backing on any fabric that can be considered as "stretchy".

Good luck to you,
Ed Orantes - Lafayette, LA
Melco Tech & Trainer
504-258-6260

[Alicante]

Hi, thanks for the additional tips.
I checked the lower thread feed limit and it is set to 1.
I moved the pressure foot to 1 click. It was at 2 clicks before.

Then, I did a test sewout using Melco Block letters 1 in. high, with th word, "test". The machine sewed fine, but beeped "thread break" every few stitches even though no thread break occurred in the entire sewout.
I'm thinking this is an electronic glitch?
Not sure how to proceed now. The manual really doesn't treat the subject of false alerts. I will look throught the forums.

[Rod or Sharon]

Dee,

It sounds as if you do have a thread break sensor that is not working properly.

Here are a couple of items to check. Remove the needle case cover. On the front face of the needlecase and toward the left side, you will see a small PC electronic board. There are two very small wires soldered to this board. Check them carefully to see if one or both of the solder joints have failed. if they have failed..the thread break sensor needs replaced.

If the solder joints are ok.....you will also see where a cable is plugged into the PC board. Make sure this is secure, unplug it and plug it back in a couple of times. Sometimes a slight bit of corrosion can affect one of the plug-in pins and cause it to not allow proper signal transmission to take place.

THE NEXT ITEM TO CHECK WILL BE DONE AT YOUR OWN RISK.

The same cable that attaches to the little PC board you just excersied by plugging and unplugging, also is plugged into the Main PC or Motherboard. It should also , for trouble shooting purposes, be plugged and unplugged a couple of times. Do not pull on the wires, work the connector carefully to unplug it and be careful not to bend the pins when pluging them back in.

TURN OFF THE MACHINE. BECAREFUL OF ANY STATIC DISCHARGE THAT YOU COULD IMPART TO ANY OF THESE PC BOARDS. A static spark can damage sensitive elements in these systems.

The cable that is plugged into the little PC board should be labled as a J79 cable. On the Main board a connector will also be labled J79 where it plugs into. It is located on the right side and towards the front of the board. Find it and unplug and plug it a couple of times to exersise the connecting pins.

As I said, you proceed into this area with caution and at your own risk. Mistakes here can be costly, not so much with physical harm, but by damage to equipment if not done properly....TECHS use a grounding wrist strap to insure no static sparks occur while working around the PC boards.

Tackle these one at a time as a process of elimination.....

If none of these suggestions bring the thread break sensor back to life, a replacement and/or tech call is in order which of the latter, may be something to consider as this should fall into the warranty catagory, i.e...if your machine is still under warranty......

Rod Springer
Amaya Tech & Trainer

[Alicante]

Thanks Rod,
I will check those things. I've made a printout...If nothing else I'm compiling a useful addition to my Amaya users manual!

[Alicante]

I did those checks, Rod, I execersied the cable connetion on the needlecase front panele and the one on the PCB. I only found a cable called J29, not J79 in the right-hand side, the cable said thread feed.
I couldn't find any with J79.
Unfortunately nothing changed to be a so it will have to be a tech call.
Thank you for the help.

Off topic, but anyway I just wanted to say, I have my home for sale here. I plan to move to a town west of Fort Worth and restart my business there in the next 5-6 months.

[signman]

Here's a tip that works on the 'big red' Amayas...might work on the XT (Rod, can you confirm this for me?)
Behind the thread in the middle of the needle case, is a 'silver tube' with red ends. The thread sensor is inside this...and when we ran into problems with a lot of breaks on Big Red, we would just gently 'rotate' this rod a half turn-and the problem would go away. Not sure why but it works! A tech told us to do this a few years back...we just got our XT but I haven't checked to see if the tube turns...do not try it until someone says it will move or you could break something.