Bj Dixon Report post Posted July 1, 2020 (edited) Well, I'm stumped. I'm putting my Singer 331k105 back together after a clean and refurb. Everything was going fine and it's not that complicated a machine. I had photographed and witness marked everything I could and anything that would come out as an assembly, did. I knew adjustments would be off, but should have been in the ballpark, even if they are waaaaay out at the outside wall in left field.... I had the rotary hook assembly back together and timed fine. It was catching the needle thread and going to the bottom to thread it back up and around, catching the bobbin thread. But then, for no apparent reason, it started not spooling the thread around the bobbin/case to make the loop that catches the bobbin thread. I thought something might have shifted, but everything checked tight and secure. Ive checked everything for hooks/snags/burrs/dirt; nothing. I rechecked the timing and the needle bar heights: nothing, all checked good. I'm baffled. One thing I did notice is the hook doesn't seem to be rotating the same/amount as it did. It seems like it wants to goo to far to the rear (it will actually catch on the bobbin case spring screw where it's raised a little) and then it's like it is not rotating towards the front enough to "flip the thread". Singer manuals are useless, they don't go this deep into servicing/maintenance. There's no service manual for a 331k105, but there are some for the 331k's and the 31-19/47 models. But again, far too simplistic for what I seem to have going on here. They only address the tings someone may run into at home, like hook timing, etc. Any ideas on where I should look next? I'm almost out of ideas.... Edited July 1, 2020 by Bj Dixon Quote Share this post Link to post Share on other sites
ljk Report post Posted July 1, 2020 I just finished a 44-20 very similar a crank oscillating shuttle machine. My problem was shuttle carrier driver and side play in the shaft. This made stitching irregular. The cure was bushing the shaft to eliminate free play. The driver had a set screw and was also pinned and hook had to be re timed. The pin was out slightly to the shaft. Time by rotating needle to bottom and then raising 1/10" should just be meeting hook. Hook should then meet needle sightly above eye. Depending on material slight adjustment my be required. Harry Rogers on YouTube has a good article on 331k. Describes problems with substandard hooks and shuttles. I've seen these machines rattle like crazy and still make a good stitch. (there is a fix for that) good luck Lynn Quote Share this post Link to post Share on other sites
Bj Dixon Report post Posted July 1, 2020 11 hours ago, ljk said: I just finished a 44-20 very similar a crank oscillating shuttle machine. My problem was shuttle carrier driver and side play in the shaft. This made stitching irregular. The cure was bushing the shaft to eliminate free play. The driver had a set screw and was also pinned and hook had to be re timed. The pin was out slightly to the shaft. Time by rotating needle to bottom and then raising 1/10" should just be meeting hook. Hook should then meet needle sightly above eye. Depending on material slight adjustment my be required. Harry Rogers on YouTube has a good article on 331k. Describes problems with substandard hooks and shuttles. I've seen these machines rattle like crazy and still make a good stitch. (there is a fix for that) good luck Lynn I would be interested in your "rattle fix" if you don't mind sharing? I was actually thinking of a hook driver swap of some type. I notice my newer oscillating hook machines have a "spring" on the driver that takes up the slack that's present in my 331k105 hook assembly.... Quote Share this post Link to post Share on other sites
Bj Dixon Report post Posted July 1, 2020 (edited) Well, I think I've got it and if it's what I think it was, I'm not really sure how the machine ran for the PO. I pretty much went "back to basics". First was to time the hook driver, then the hook itself. But I didn't time it to the needle (at first), I just made sure that once the hook had picked up the thread that it had enough rotation to hand it off and pull back up through the whole bobbin assembly. Once I got that sorted, the hook was obviously waaaay out of time with the needle. Well, to fix that, I had to loosen the set screws in the thread take up cam and re-time that. That gets the needle where it need to be in the cycle for thread pick up. Next up is to set the feed dog height and make sure the geometry is still good for the "walking foot" as messing with all those cams and adjustments has a direct bearing on how the walking foot moves during it's cycle. So far, it seems to be sorted. I have no doubt that there will be lots more fine tuning to do, but it seems I'm at least in the ballpark now. Strange thing is: the machine was at least running when I bought it and it went back together with all the witness marks lined up. I didn't see it make a stitch because it had a broken needle and she said it was out of time. If my witness marks would have been rotated 180 degrees, that would have made sense that I messed up and put it together 180 out somewhere. But some of the witness marks were out 90 degrees (or less). Perhaps it was out of time and breaking needles for the PO because someone had royally messed it up.....before I royally messed it up that is.....lol! Edited July 1, 2020 by Bj Dixon Quote Share this post Link to post Share on other sites
Bj Dixon Report post Posted July 2, 2020 (edited) Well, it's running and stitching now. But there's still a problem I need to chase down. The upper stitch is so loose, it's making big loops on the underside of the fabric. Normally you would just think a tension problem, crank it a bit more and good to go. But not this time. The tension disc is bottomed out on the thread and still making loops. So time to have a look at the tensioner, it does seem to pull throught a little too easily, even with the thumb nut all the way down. Hopefully it's just something simple like the spring has gone a little slack..... Edit: mystery solved. Need a new tensioner. I pulled the (what I'm assuming) off and gave the spring a good stretch. It;s only temporary as a spring that has lost it's "springyness"will always quickly collapse after being stretched, but it proved the point. The stitches are tighter now, but still not properly tensioned. No more big loops though, so I ordered a new tensioner assembly and (fingers crossed) that should be it.... Edited July 2, 2020 by Bj Dixon Quote Share this post Link to post Share on other sites
Bj Dixon Report post Posted July 2, 2020 (edited) quick test stitch. top: Bottom: It's far from perfect, but that was just to prove to myself it will at least make a stitch. I just grabbed a scrap of whatever was lying around, threaded up whatever came out of the drawer and just used whatever needle was in the clamp already. So not too bad, especially considering I was doing flat fabric with a piping foot on the machine (I have a flat/smooth foot on order). It grabs, just not very solidly or evenly. There's just not enough surface area between the presser and dogs to feed properly. So, now it's replace a couple tired old parts, a touch of fine tuning, and then it should be good to go. Whew, that was more of a fight than I ever wanted, but we're there! Edited July 2, 2020 by Bj Dixon Quote Share this post Link to post Share on other sites
Wizcrafts Report post Posted July 2, 2020 2 hours ago, Bj Dixon said: Edit: mystery solved. Need a new tensioner. I pulled the (what I'm assuming) off and gave the spring a good stretch. It;s only temporary as a spring that has lost it's "springyness"will always quickly collapse after being stretched, but it proved the point. Did you know that you can just order a replacement beehive tension spring? Quote Share this post Link to post Share on other sites
Bj Dixon Report post Posted July 2, 2020 (edited) 26 minutes ago, Wizcrafts said: Did you know that you can just order a replacement beehive tension spring? Yep. Ordered a complete assembly. Whatever doesn't get used will go into the parts drawer. Never hurts to have spare parts around.....especially when all your machines are in the 55-60+ years age range. I think my newest is around 45 years old.......;) Edited July 2, 2020 by Bj Dixon Quote Share this post Link to post Share on other sites
ljk Report post Posted July 2, 2020 Regarding rattle. These machines of this type singer 3115, 44s and others have conical type bushings (bearings) on rotating and oscillating mechanisms. By loosing the nut you can tighten the bushing this will reduce clearance. Also oscillating parts like feed dog shaft can be also adjusted. Also in many cases the stitch length can be lengthened by grinding the stitch length slot. (make sure you center feed dog first) Did you know you can lock starting and ending stitches by simply moving lever to 0 or close to 0. My commercial embroidery machines do this between trims and color changes. I program at 6 stitches. As to tension my embroidery machines run bobbin tension at about 25% of top tension. These are really lock stitch machines with fancy electrons xyz axis. Looks like you are on your way to a good machine. tx Lynn Quote Share this post Link to post Share on other sites
DonInReno Report post Posted July 3, 2020 On 7/1/2020 at 9:41 AM, Bj Dixon said: Perhaps it was out of time and breaking needles for the PO because someone had royally messed it up.....before I royally messed it up that is.....lol! Im quite sure at least a couple of other people have had a go at it before you - that seems to be human nature with sewing machines - they just have to take things apart or at least turn screws not knowing exactly what they do. Lol Quote Share this post Link to post Share on other sites
