Top thread breaking when rotating slowy?

[drem312]

thanks again for all the other help my vinyl is all sewed up and seams sealed nicely,,,now Im trying to get the Old  Inustrial Tacsew machine going,,, thru you tube I was threading it wrong got that fixed timing was off adjusted the needle so  the hook does pick up the top thread but when I slowly turn it and watch the thread in the hook start to head around the bobbin case it binds underneath it and then shears it off,,likethe hook is a pair of scissors.... i cant figure out why,,, theres seems to be no burrs,, tension tight or loose doesnt matter,,, needle isnt involved at this stage,,,any ideas,,Im brining it in in the am to a shop but I wanted to try and save some cash ,,, thanks again

[Mike8560]

Is the needle orintated to the kerf the notch I. The needle is facing the bobbin?
If not this wouldn't low room for the thread to pass ans cut it. 

[drem312]

the  long groove side is facing toward the bobbin and  the notch side is facing inward on the hook side

[drem312]

I just got a partilal manual for it and it says  needle size  DBx1#21   what does this mean in today needle size? the machine is for heavy use a 3300spm stich length 0-7mm

[jsquail]

I just got a partilal manual for it and it says  needle size  DBx1#21   what does this mean in today needle size? the machine is for heavy use a 3300spm stich length 0-7mm

its a type DBx1 needle. the size is 21 gauge.

There are several different types of needles. Different machines use different types of needles.

As i found in my research all the needles listed below are the same type of needle. I could never figure out why the differences in numbers though. But i can say this with certainty, the differences in the length and shank size of these needles is so minute you need a set of calipers to see it.

DBx1
16x231
287
1738
16x257

There is a needle and thread size guide in the forums its located here:

http://get-up-and-go.com/upholstery-forum/index.php?topic=6371.0


I hope this helps!

[Gregg @ Keystone Sewing]

jsquail,

100% correct.

The confusion is that in some BRAND systems, the DBX1 stops at size 18, and then becomes the DBX95.  Others still use the DBX1 as is the case here;

DBX1 is the system, also known commonly as 16X257.  Depending on brand, could also be known as DBX95 or 16X95 after size 18.  Very confusing, but you have the correct needle system for sure.

21 is Singer/Old Asian designation for size, Also known as NM (number metric) 130 is the size, or the thickness of the blade of the needle that penetrates the material.