Missing stitches - Why?

[UKRay]

I recently tried to change the thickness of the tread I use on my ancient BUSM Pilot sewing machine (I wanted to use a thicker thread). Suffice to say it wasn't a success and I am now trying to reverse engineer the process... without complete success as the machine now stitches perfectly for about 5 or 6 inches then misses two stitches and then carries on stitching perfectly. It keeps on doing this - 5-6 inches and 2 missed stitches and I am at my wits end trying to find a solution. I am sure it is something to do with the thread tension but I can't work out how to fix it - any ideas?

My feelings are I may have the top tension a tad too tight - I don't seem to have any obvious adjustment on the bobbin although I could be wrong about this - I have tightened and loosened but can't find the optimum point - Any suggestions would be gratefully received - and before anyone suggests it, I'm not going to buy an Artisan machine just yet 'cos I simply can't afford it but the temptation is definitely there...

[celticleather]

I don't know anything at all about BUSM sewing machines, but most machines have a small screw on the bobbin-holder that adjusts the pressure of a small leaf-spring which grips the thread at the point where it emerges from the shuttle, and gives the bobbin tension.

If it exists, perhaps it was the fact that this was too tight which prevented the thicker thread experiment from working.

I may be talking out of the top of my head, but I've no doubt there's someone who knows!

[rdb]

When one of my machines starts acting up like that, the first thing I do is curse at it!

The next thing I do is start over. I pull the thread out and rethread the machine from scratch, making sure I have all the loops and doops in the right place, checking twice.

Then I go to the bobbin thread. Usually, I'll rewind a new bobbin, in case the one in question is wound too screwy, just like me.

After replacing the bobbin, and putting it under the spring, I undo the main tension, and upper tension screws almost off their posts. I place some leather under the needle, and start tightening the tensions, a little at a time.

That usually works for me.

If it's still not quite right THEN I start readjusting bobbin tension screws, checking needle sizes etc.

Good luck, but I'm sure you'll get it. Just consider it Quality time with your machine...lol

[Art]

Hi Ray,

Needle size can affect tension if not correct for the thread. When you go up in thread size, you may have to get a larger needle too.

Art

[Bob]

Hi Ray,

Needle size can affect tension if not correct for the thread. When you go up in thread size, you may have to get a larger needle too.

Art

I agree with Art's comments. When the thread size changes, you should look first at the needle size too.

Bob

[Hennessy]

I agree with Art's comments. When the thread size changes, you should look first at the needle size too.

Bob

what i allways done with my union lock was [it was on wheels ]rolled it out and into my pick up and headed for a potholed gravel road out of town,up n down th either the road or threat of being dumped seem'd to straighten ver straight up petee road a time or two then back to shop

[Hennessy]

what i allways done with my union lock was [it was on wheels ]rolled it out and into my pick up and headed for a potholed gravel road out of town,up n down th either the road or threat of being dumped seem'd to straighten ver straight up petee road a time or two then back to shop

up and down a time or two then back to shop.either the threat of being dumped or the bumpy road seem'd to straighten er straight up adios pete

[SteveBrambley]

I recently tried to change the thickness of the tread I use on my ancient BUSM Pilot sewing machine (I wanted to use a thicker thread). Suffice to say it wasn't a success and I am now trying to reverse engineer the process... without complete success as the machine now stitches perfectly for about 5 or 6 inches then misses two stitches and then carries on stitching perfectly. It keeps on doing this - 5-6 inches and 2 missed stitches and I am at my wits end trying to find a solution. I am sure it is something to do with the thread tension but I can't work out how to fix it - any ideas?

My feelings are I may have the top tension a tad too tight - I don't seem to have any obvious adjustment on the bobbin although I could be wrong about this - I have tightened and loosened but can't find the optimum point - Any suggestions would be gratefully received - and before anyone suggests it, I'm not going to buy an Artisan machine just yet 'cos I simply can't afford it but the temptation is definitely there...

Hi Ray,

I had a similar problem with missing stitches with our BUSM Pilot, it was suggested to me - by you know who - that I moved the thread looper hook a little forward. I did this, and it now stitches fine, without missing stitches. If you don't know how to do this pm me and I'll try and explain the process.

Steve

[Geordie]

Hi Ray,

I used to share a workshop with an industrial sewing mech.He always said the first two things you MUST do are charge the needle making sure it is fitted correctly and of the right size for the thread being used and then re-thread your machine.

It sounds to me as if the timing is out.

[UKRay]

Sorry guys I may have been a little misleading with my initial post. I wanted to use a thicker thread but I couldn’t get my machine to work with the thicker thread and have been trying to get it back where I started with the ‘regular’ thread. I’m doing something wrong but it definitely isn’t the threading of the machine. I have refilled the bobbin with the regular size thread and re-threaded the whole machine according the photographs I took when it was first set up so I guess that just leaves the tensioner.

Both threads are pulled up tight to form the stitches and the stitches look perfect – then it misses two together – or actually, I guess it only misses a single stitch as one hole makes two stitches if you see what I mean – I think I must have it too tight. Any thoughts on my thinking? LOL

Oh yes, the needle size is the same as when I started and it worked okay then,

[SteveBrambley]

Hi Ray,

There is still a possibility that the 'looper hook' may have moved or come loose. The Pilot works differently to most lockstitch machines, there is a hook that grabs the thread loop and pulls it across for the shuttle hook to grab like a conventional machine. I found that if this 'looper hook' is too far back (or forward) it will miss the thread and drop a stitch.

Of course, it might be something else, but it's worth a try.

Steve

[Bob]

I likes the idea of throwing in the ditch and starting again.... loading it into the truck and heading for a gravel road, threatening to dump it sounds pretty good...

[tonyc1]

Why do that, you know as well as I do that sewing machines have no feelings whatsoever. They are born to be perverse critters!

Tony.