cumberlandharp

Gregg, Thank you for that. When I mentioned above that I could "cheat" my way to longer forward stitches, that's what I was referring to – that I was moving that clamp on purpose to allow more bias to the front stitches. If I balance that area to produce identical forward/reverse stitch lengths, I end up back at 6/spi in both directions.

So here I am, one year later, and this machine is still having issues with stitch length. I'm looking for any ideas as to things I can adjust to affect the stitch length. The only update I have is that I have discovered that I can "cheat" my way into getting longer forward stitches if I adjust the stop screws affecting the forward and reverse travel to be unbalanced. This will give me longer forward stitches, but it makes the reverse stitching shorter, of course. This does tell me, however, that longer stitches are possible – I just can't figure out how to tap into them. Any and all suggestions for things to adjust are welcome.

Thanks again Uwe for your replies. As you suggested, I think my best course of action is to compare the movement and mechanics of my machines side by side. I’ve already been doing that, but I’ve only really been concentrating on the more likely culprits in the linkages. I believe more scrutiny is in order for the tertiary parts. I will follow up with the results of my troubleshooting. If I get it corrected, I will be sure to update this thread for future patrons of the search function. Readers, if there are any other suggestions for me, I would greatly appreciate any and all input.

After inspecting the areas that you mentioned, Uwe, I was unable to find anything amiss. My stop screws are still set up the same way as the other machine I have; both the machines behave the same way in that regard with a normal range of motion for the reverse lever. Also, my stitch length eccentric looks just like yours and rotates from the same zero to the same maximum as the one you photographed. Could there be anything else involved with the reverse linkage that could be causing this? I did take that apart when swapping out the timing belt. I wonder if something else could have been reassembled incorrectly.

Thanks Uwe, this is great information. I haven't checked those stop screws you mentioned, so I will do that and report back.

Hey guys, TL;DR version: My stitch length maxes out at 6/spi. I have another identical machine that can achieve close to 4/spi, so I know I can get the stitches longer, but the stitch length regulator is already maxed out. Looking for advice on what I need to look at to regain the full stitch-length spectrum. Details below. Longtime lurker, first-time poster. A couple of years ago, I took over the management of our sewing department at work due to the retirement of a longtime employee. I have learned over time to do basic maintenance and adjustment of our machines. However, I have one machine right now that is repeatedly giving me issues and I'm at a loss for what to do. I do have a sewing machine repairman who has been very helpful to me over these years and has taught me a lot, but he is having health problems right now and is unavailable. So I'm turning to you guys for any suggestions I can get. The machine in question is a Consew 339RB-1. It's a double-needle, walking foot machine with reverse stitching. I have two of them in operation, which is very helpful for side-by-side comparisons, but I still haven't figured out what is going on. My problems started about a month ago when the operator popped the safety clutch. I reset the clutch, timed the needles, and all seemed well for a couple of days. Then the clutch popped again, but this time the timing belt broke. So I replaced the timing belt and went about looking for what else might be going on. During this process, I have timed the needles, tightened up the play in the safety clutch, adjusted the needle bar height, adjusted the feed dog height, taken apart the stitch length regulator for de-gumming, adjusted the hook to needle clearance, and adjusted the reverse stitching to match the forward stitching (I am just listing everything I have touched on this machine, even if irrelevant to the question at-hand, just so you know where my hands and tools have been). After all of this, the machine sews pretty well; no thread breaks and very few skipped stitches, which is a great improvement. However, I cannot adjust my stitches to be any longer than they are right now, which is about 6/spi. I can adjust them down to 0, but it seems to me that the stitch length regulator pegs out too soon and I can't achieve the default maximum stitch length. I know that they can be longer because I have another machine that is identical to this one that is set to 4/spi with a bit of room to go even bigger. Plus, before the operator initially tripped the safety clutch, I could adjust the stitch length up and down without any issues. My suspicion is that during the timing belt replacement I did something incorrectly, but it's hard to know what it is considering the machine is sewing nicely. I'd appreciate any leads or suggestions anyone might have regarding what I need to check or adjust next. I don't know if there's any other information you guys need, so just ask if you need further details about the machine or what I've adjusted so far. I have used the search function here and checked out every relevant post I could find, but my issue persists. TIA.