Consew 206RB-5: Not picking up bobbin thread

[CowboyBob]

2 minutes ago, MtlBiker said:

Thank you!  You were right (it seems) because when I held the little button on the top for the safety clutch and turned the hand wheel, I did hear/feel a sort of pop.  It must have been out.  And now it looks like I've really messed things up... I can pick up the bobbin thread but the machine isn't forming stitches.  When I try to sew, everything is working perfectly but no stitches are formed.

A little knowledge... is a dangerous thing.  SIGH

 

Tilt the machine back,look @ the clutch & then turn the machine until you see the hole in the outer part & make sure you can see the BB in there B4 doing anything else.I'm sure it's in there BUT we need to know for sure.

[Constabulary]

if not the safety clutch then IMO the NB is too high AND the hook is too far away from the needle scarf.

Edited July 5, 2021 by Constabulary

[kgg]

 

12 minutes ago, Constabulary said:

the hook is too far away from the needle scarf.

I looked at your video and agree with Constabulary that the hooks to far away from the scarf. I figure you have either a damaged hook like the tip missing or the rotatory hook assembly moved away from the needle as a result of a needle overload, strike or the abrupt kicking in of the clutch. I would check and see if the hook assembly set screw has become loose on the shaft. I would reposition the hook assembly forward on the shaft and re time.

kgg

[MtlBiker]

2 hours ago, CowboyBob said:

Tilt the machine back,look @ the clutch & then turn the machine until you see the hole in the outer part & make sure you can see the BB in there B4 doing anything else.I'm sure it's in there BUT we need to know for sure.

Yes, it's there.  (Took me a bit to find it, because I was looking right below the reset button on the flatbed.  I didn't realize the safety clutch bearing was 3.5" to the right of that.)

 

1 hour ago, Constabulary said:

if not the safety clutch then IMO the NB is too high AND the hook is too far away from the needle scarf.

I had already adjusted the needle bar height according to the YouTube maintenance video.  So as @kgg suggests, it might be that the hook is damaged, although it doesn't appear to be but I have nothing to compare it with, or something else.

 

[MtlBiker]

37 minutes ago, kgg said:

 

I looked at your video and agree with Constabulary that the hooks to far away from the scarf. I figure you have either a damaged hook like the tip missing or the rotatory hook assembly moved away from the needle as a result of a needle overload, strike or the abrupt kicking in of the clutch. I would check and see if the hook assembly set screw has become loose on the shaft. I would reposition the hook assembly forward on the shaft and re time.

kgg

I'm not sure what set screw you're talking about.  Do you mean the 3 set screws on the shaft just by the safety clutch?  That's what I need to adjust to set the hook timing, right?

And I'm a little confused by what I've read in a couple of places... one said the point of the hook needs to be centered within the scarf of the needle (once the needle bar is properly adjusted) and another said the top of the needle hole.  On the video it looks like it's not really the sharp point of the hook that's centered on the scarf, but a little ways back from the point that's centered.

Obviously, I don't get it (yet).

[kgg]

 

2 hours ago, MtlBiker said:

'm not sure what set screw you're talking about.  Do you mean the 3 set screws on the shaft just by the safety clutch?  That's what I need to adjust to set the hook timing, right?

I think this video around the 52 minute mark should help you with moving the hook assembly forward, set screws and timing the  "Consew 206RB 5 Maintenance Video Part 1" (youtube.com/watch?v=y4ACNMX65zE).

kgg

 

[MtlBiker]

14 hours ago, kgg said:

 

I think this video around the 52 minute mark should help you with moving the hook assembly forward, set screws and timing the  "Consew 206RB 5 Maintenance Video Part 1" (youtube.com/watch?v=y4ACNMX65zE).

kgg

 

That's the video I've been watching.  But parts of it aren't entirely clear to me (novice that I am) and many parts are out of focus so it's hard to see exactly  what's going on.  But overall those videos (there are two) are superb.  I imagine someone with more experience than I would have no problem at all.

Still not clear on whether the pointy tip of the rotary hook is what has to be centered vertically on the scarf, or closer to the top of the eye of the needle.  And if you advance the timing, doesn't it mean the point passes the needle sooner than if the timing is retarded? 

I gave up last night and now I'm at work all week with very little time in the evenings to work on this.  Might have to wait until Sunday/Monday (which is my weekend).

[Constabulary]

The instruction manual is pretty clear with the timing values - SARK9 posted an extract above. If you do not have the complete manual download it.

[MtlBiker]

Chances are that my rotary hook is damaged, but I don't have the experience to know for sure.  Nor do I have a new one to compare with.  So I thought I'd buy a new one just in case.  Supposedly it's part #18033.

Online I see them for $35-50.  My Consew dealer just quoted me $374 plus taxes!  Is that even possible?  Could there be some misunderstanding of "rotary hook part #18033"?  Could the dealer be quoting me for some kind of complete assembly?  Geez, that makes the hook about 30% of the price I paid for the machine!

 

[Wizcrafts]

I run a Consew 206rb-18, which is the same thing but longer. I time this machine so that when the needle has risen about 3/32" the very tip of the hook meets the center of the needle 1/16" above the top of the eye. If I encounter skipped stitches after that I move the hook saddle closer to the needle and bend the deflector if necessary so the hook comes as close as possible but doesn't actually hit the needle.

Did you know that a left to right threaded needle tends to get pulled to the left as you sew? The amount of pull varies with the diameter of the body and how tight the top and bottom threads are tensioned. A number 16 or 18 needle will be pulled more to the left than a number 20 or 21. This explains why a perfectly timed machine might still skip stitches. Other factors come into play, but needle pull can't be ignored. Obviously, if you reduce the thread tensions to the minimum that still gives a good stitch, the deflection will be minimized.

Lastly, observe the check spring as you hand wheel the machine. It should rest all the way down against the bottom stop bracket (adjustable) then pull up smoothly as the take-up lever moves up. As the take-up becomes let down, the spring should keep the top thread taut until the needle has fully pierced the material, then it should stop against the stop bracket. The spring tension should be strong enough to bring the spring down to its resting position, but not much more than that.