Beanwood

Thanks - that's the one I've been using, allied with the Sailrite one https://www.sailrite.com/Selecting-the-Right-Thread-Size

Thanks - some good points there. I agree with you - with the stroke being driven by crank - I coudn't see an easy way of increasing it - hence my surprise that it was apparently done by @GPaudler and wondering how he managed to sew 12mm rope - as I want to do!! I suppose it could be possible to increase the crank length, but that looks pretty hairy to me. Regarding thread weight - I've never managed to find a good US to UK conversion of V69 etc - but it's happy enough to sew with Metric 27 - Tex 105? so not by any means te heaviest, but not too bad. (I'll ty some M20 when get a few minutes.. It's strangely satisfying watching a 10mm ZZ in M27 thread

Following on from the various threads recently about changing needle bars, I had a thought... I don't sew much leather, rather I sew webbing of various thicknesses. I had a need to sew some zigzag stitches, and ended up purchasing a Brother TZ1-B651 - it's an industrial machine, capable of 12mm zigzag, but doesn't have a walking foot, and uses really puny needles. I'm adding a pulley speed reducer (6" to 2" reduction), to reduce the speed, and increase the torque of the clutch motor, but I was thinking I'd really like to change the needle bar for something that will take the same needles as my other machines (DPX17 - I'm UK based, and that's how we know them), but I'd also like to increase the stroke, so I can join some 12mm rope. I saw a comment on here from @GPaudler that changing the stroke to do exactly this was straight forward, but as he hasn't been back on since 2018, I can't ask him... So, 2 initial questions: 1. Is the replacement needle bar simply a case of getting a DPX17 bar with the same dimensions? 2. Does anyone have a link to anywhere that might show me how to increase stroke length please? I know the answer is probably to spend £1200+ buying a pre-owned machine that will do the job proerly, but I'm starting up a new business, and funds are tight right now for what may not work out anyway.. Thanks for reading.