Jump to content
Parott1

Cb4500 tension

Recommended Posts

I've been using #138 thread on my Biothane Beta dog leashes, but recently tried going to 277 top & 207 bottom; per Biothane's recommendation.  I can't for the life of me get the knot to pull to the center.  It's at the halfway to 2/3's on the bottom piece.  Anytime I back tack, the bottom looks like crap because the knots aren't pulling up and are all jumbled up on the bottom.  

 

The machine is threaded correctly and the thread is ran through a lube pot.  I tightened the side and top tensioners exactly how Ryan Neal shows in his YouTube videos.  I've also tried to tighten and loosen the bobbin tension to no avail.

Does anyone have any suggestions?

Share this post


Link to post
Share on other sites

Try 1 larger size needle. 

Share this post


Link to post
Share on other sites

I'm using a size 26 needle

Share this post


Link to post
Share on other sites

Im sorry I cannot add to assisting you as my suggestion would have been the bigger needle as well... however would you mind sharing any good biothane distributors? I've been meaning to get some pieces and mess around with it. 

Share this post


Link to post
Share on other sites

Biothane is wicked. Not only do you need to use a larger needle, but you also need to tighten the top tension, or loosen the bobbin spring. Also, not estableshed, but try using a non-leather point needle. This stuff is made of vinyl, which is usually sewn with a round/sharp point, not a leather point. A compromise would be a tri-point needle.

Share this post


Link to post
Share on other sites

I'm using a 794S size 26.  How I have the top tension pretty tight.  How tight should the bobbin tension be in comparison to the top tension?  

I had 277 on the top and accidentally had 138 on the bottom. The knots were pulling right into the center.  When I went up to 207 no matter what I did, the knots wouldn't budge

Share this post


Link to post
Share on other sites

Yeah the S needles dont do as great for thick leather or other tough materials IMHO. 

Share this post


Link to post
Share on other sites

What kind of needle should I be using? 

Share this post


Link to post
Share on other sites

I finally got the knots to pull through to the center, but they are inconsistent. Some stitches has the knot pulling to the upper piece of beta and other stitches have the knot more towards the bottom.  Could this be caused by loose bobbin tension?

Share this post


Link to post
Share on other sites
55 minutes ago, Parott1 said:

What kind of needle should I be using? 

 

1 hour ago, Wizcrafts said:

Biothane is wicked. Not only do you need to use a larger needle, but you also need to tighten the top tension, or loosen the bobbin spring. Also, not estableshed, but try using a non-leather point needle. This stuff is made of vinyl, which is usually sewn with a round/sharp point, not a leather point. A compromise would be a tri-point needle.

 

Share this post


Link to post
Share on other sites

The problem with Biothane is that it is religious and heals the holes instantly, just before the knots are pulled up. I had better luck sewing Biothane on a Union Lockstitch than on my CB4500 or a Cobra Class 4.

Share this post


Link to post
Share on other sites

After messing with the tension I had it sewing perfect. Then when I went to use it today I was having problems with it in reverse.  

When I start my leashes, I start it in reverse, sew 3 stitches and then sew forward.  Well today the bottoms of the rev/forward look like spaghetti on the bottom.  It's also now skipping stitches i.e. On the 3rd stitch in reverse I go past the bottom dead center and go forward.  It just skips the last stitch and leaves me with a hole where the needle went in.  This also happens when doing a turn.  The needle goes in, then I go past BCD and turn.  The thread just pulls out and skips the last stitch.

Could this be a timing issue?

Edited by Parott1

Share this post


Link to post
Share on other sites

Make sure the hook pics up the loop before changing direction. May have to bring the needle up a quarter inch on the up swing before this happens (sounds like ya were doing this)

Also check the allen head bolts thru the access port where the reverse/stitch lever is (not too tight or the handle will be very hard to move). Ive also found the one in the access plate below the lever may need tightening as well.

It still happens on mine occasionally but is reduced. 

 

Edited by MADMAX22

Share this post


Link to post
Share on other sites

Not sure if this can be of any help in diagnosing the problem,  but I did a few test pieces just sewing backwards.  The machine skips a stitch every 3-4 one.  The underside also looks very sloppy.  Bobbin thread loose and not pulled tight to the material 

Edited by Parott1

Share this post


Link to post
Share on other sites

North east Pennsylvania 

Share this post


Link to post
Share on other sites

The machine appears to be in time. I'm using silicon lube that I got from Ryan Neal

Share this post


Link to post
Share on other sites

Black 277 top and 207 bottom the brand is cowboy 

Share this post


Link to post
Share on other sites

Anybody have a chart about what thread size on top would fit with a different size on the bottom. ? Thanks. 

Share this post


Link to post
Share on other sites

The first pic is the top side of the stitch. Forward is the top with the tail and the bottom is reverse. 

The second pic is the bottom side of the stitches.  Top is forward and bottom reverse. 

As you can see the bottom stitch is slightly smaller and the bottom side of reverse looks like it just runs on

IMG_7148.JPG

IMG_7149.JPG

Share this post


Link to post
Share on other sites

Sorry for the poor quality pic.  Yes I'm still using the s point.  Biothanes website recommends a round point in either #25 or 26

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...