Burr, And it isn't even cold!
With this chapter we want to investigate
the physical condition of the sewing machine's hook.
This picture shows an oscillating hook ( See our wonderful chapter on
different kinds of fans for a refresher if
you need it) The blue arrow is pointing to the hook ti
p
and the checkered arrow is emphasizing the
area just behind the point, usually there's either a little indentation at this
spot or a little fat bulge at the spot right between the two arrows.
There are rotary hooks accessed from the bottom and rotary hooks accessed from the top. We can't cover them all but the principles elaborated below are the same for them too.
The hook point has to pass behind the needle at the scarf area just as the needle is on its way up and forming the loop lift. The tricky part is that the point has to be not only in place at the correct time (timing) but the hook/needle distance has to be so close that...well, for example...a sheet of paper might fit between them.
ok, a qualified technician can render those tolerances correctly for different machines. but for most folks even if you know how far apart to make them, you probably don't know which screws to turn, and in what order so don't try it.
That's a definition of the mechanics.
The problem is that if these distances aren't right then the machine skips stitches OR the needle strikes the hook and creates "BURRS" (therein the title of this chapter. These needle strikes on the hook will catch the thread whilst the hook and needle are making the stitches and all of a sudden you have a ball of thread bunching up underneath your fabric. Sometimes we work on machines that have hooks so badly scarred that we have to replace them. A few times a soft stone will do the trick, but we have to be careful about that remedy because that can affect the hook/needle distance, among other things.
But there are things you can do to keep this problem away, at least for a bit.:
First, you realize how close things have to work and do it in a mightily fast sequence for every stitch, .
Secondly, realizing that, then you can understand that a needle, particularly when working on heaver fabric, can get microscopically bent. . This invisible bend will cause the needle to strike the hook...you might not even be aware of it because it will glance off in the checkered arrow spot. Not good.
So you need to change your needle at least with every garment. Throw it away... Come on: Don't risk your fabric, your time, and your machine in order to save 20 cents on a needle. We'd have a hard time telling you the number of times someone has come into our store and bragged about not having to change the needle in "her" machine since the 1950s.
third, change your sewing habits. If you guide your fabric underneath the presser foot with your right hand and then use your left hand behind the presser foot to "help" things along, then you are putting pressure on the needle, stressing it, and you will be causing needle strikes. not good. You really shouldn't have to use your left hand at all, especially if you are using one of today's more modern machines. Otherwise, trade it in.
If you do these two things then you will stop the two main causes of burrs on the hook. The final thing you can do is to get a qualified technician to go over your machine on a periodic basis. If you have been reading this series then you are beginning to pick up the feeling that a sewing machine is quite complicated (and we haven't finished yet) and that the guy down the street or in the back room at the department store--even the fellow who used to work on machines at the sewing factory---well with all the best of intentions, we'll say that this person, as nice as he is, is probably not qualified to fine tune your machine especially if yours is a recent higher end model.
By the way, our technician's corner is operated by a highly trained woman, backed up by a highly experienced staff. On any given day we generally have about 10 machines waiting in line for us to pounce on. While taking a day to write this page there have been 4 brought in. They range from high end Berinas, Pfaffs, etc. and lower end 20 year old "Mother in Law gave it to me" specials. In the past year we've had only two we wouldn't (that's wouldn't) fix. They were $80.00 Wal-Mart thingys that would cost more than that to repair and they weren't worth the possible repair bill.
