one head sewing loose

urtica

I have a Tajima 4-head. 3 of them are just fine, but one sews "loose". The stitching on the top is not tight, and the stitching on the bottom has loose loops. It appears to be a tension problem, specifically on the bobbin side since the issue is on all needles. I have swapped bobbins between the heads and it is not that. I have included a few pictures of the issue. I would be very appreciative if anyone has a hint as to where the problem lies.

twok4hd

Hook gap or timing? Needle depth adjustment? Don't know on Tajima, but one adjustment effects all needle depths on Barudan. Just a thought.

Did anything happen to that one head that did not happen to the rest of the heads at some point?

__________________
Glenn
Sew Fine Designs

dgeorge

like twok4hd said

hook timing (200deg)
gap between tip of rotary hook and needle(aprox 0.1-0.3mm)
needle bar lower dead point


verify if between rotary hook basket and rotary hook support is aprox 0.8 mm space to pass the thread
verify if rotary hook support don t have burr

urtica

Although I am technically and mechanically competent, I will admit my ignorance. Are there any diagrams/pictures that will show what I should be checking or sources where I can download what I need to be doing?

Thanks

twok4hd

I would try googling for a service manual for your model machine. Sorry I can't be much more help than that. If you had a Barudan like ours, I could help.

__________________
Glenn
Sew Fine Designs

twok4hd

Here is a link to a Tajima multihead service manual. This may not be your model but may give you an idea of what we are talking about.

http://www.hirschinternational.com/S...nce_guide.ashx

__________________
Glenn
Sew Fine Designs

dgeorge

www.embroiderytrainingvideos.com for many advices and swf dvd repair.
is not tajima but mechanical many parts are the same
if you will have problems in the future you can ask me

Eric

The fundamentals are still all the same. However there are different tips and tricks, and equally different machines are known for their little quirks.

What model/series is this machine? The reason i ask is because of the display panel. Perhaps we can alter a setting to get you a little better results, although if the problem is that extreme, it probably wont do much, but it's worth a shot.

Im in agreement with the others, At first glance. It does appear that it is a timing issue. Is this something that has been getting progressively worse? Or did it all of a sudden just happen? Did something happen to that head, like needle break or really bad "birds nest" did it catch a piece of fabric and eat it?

dgeorge

my friend,did you solve the problem?

Gabriel

sounds to me like needle depth issue or needle-hook gap.. can not be timing because is common for all heads and 3 work fine.
You need to manually go to lowest point and check needle depth. There is a gauge that comes wth all tajima machines to verify this.
Other hint would be to check gap between needle and hook. should be 0.1-0.2 mm. No idea how to check?, turn needle 180 degrees and should touck hook. when done turn needle around to its original position.
good luck!