Z320 Posted January 30, 2021 Report Share Posted January 30, 2021 Hi, perhaps someone can check and confirm - or tell me correctly - the dimensions of the speedo cable on the gearbox end? I measured 3 mm x 3 mm on the cable and the thread with 3/4-26 tpi (BSCY?)? Thanks in advance Ciao, Marco Quote Link to post Share on other sites
BlueTR3A-5EKT Posted January 31, 2021 Report Share Posted January 31, 2021 (edited) 16 hours ago, Z320 said: Hi, perhaps someone can check and confirm - or tell me correctly - the dimensions of the speedo cable on the gearbox end? I measured 3 mm x 3 mm on the cable and the thread with 3/4-26 tpi (BSCY?)? Thanks in advance Ciao, Marco Yes the square is 3 mm. I guess you have measured your existing TR cable. The thread is British Standard Brass. BSB. https://britishfasteners.com/threads-bsb Peter W PS Swage your own square ends. Years ago we had a tool for this process so we could convert or repair inner wires. It ended up cheaper to supply a full cable assembly which had a guarantee. Useful in a repair garage. It was not unlike this:-http://www.frets.com/HomeShopTech/Projects/SpeedoCable/speedocable.html Edited January 31, 2021 by BlueTR3A-5EKT Quote Link to post Share on other sites
Z320 Posted January 31, 2021 Author Report Share Posted January 31, 2021 Thank you Peter! The square end on the cable is not the problem. Yes this is 3 mm on my old cable, I learned this must mean nothing... The challenge is the square hole in the DIY angle drive! I guess I use a spare part on from a Simson motorcycle, I just wait for a answerfrom the trader. BSB, what else!?! Why not BSCY? 60° chisels I got in my workshop, but shure not 55°... Ciao. Marco Quote Link to post Share on other sites
BlueTR3A-5EKT Posted January 31, 2021 Report Share Posted January 31, 2021 (edited) In UK these are cheap enough to buy. External thread. https://www.ebay.co.uk/itm/373367994625?chn=ps&norover=1&mkevt=1&mkrid=710-153316-527457-8&mkcid=2&itemid=373367994625&targetid=4585307089523167&device=t&mktype=&googleloc=&poi=&campaignid=398226959&mkgroupid=1307319560325307&rlsatarget=pla-4585307089523167&abcId=2145997&merchantid=87779&msclkid=f74f3cdace0d1b5d77b55ccdf3470b6a For internal thread could you use or adapt an old speedo cable threaded nut end? could grind your own threading tools and check with this type of gauge https://www.rdgtools.co.uk/acatalog/SCREWCUTTING-GAUGE-WQ769776.html cheers Peter W Edited January 31, 2021 by BlueTR3A-5EKT Quote Link to post Share on other sites
Z320 Posted February 1, 2021 Author Report Share Posted February 1, 2021 I hoped you say: use te 60° chisel.... 11ER A55 I get cheap from China - in 4 - 6 weeks.... https://www.ebay.de/itm/10pcs-11ER-A55-SMX30-Threading-turning-carbide-inserts-turning-inserts-11IR-16IR/153190290415?hash=item23aada53ef:g:KpgAAOSwt6Nbpcus This is the system I use Quote Link to post Share on other sites
BlueTR3A-5EKT Posted February 1, 2021 Report Share Posted February 1, 2021 Making the square hole. You need a 3mm broach Horology is your friend Quote Link to post Share on other sites
BlueTR3A-5EKT Posted February 1, 2021 Report Share Posted February 1, 2021 3 hours ago, Z320 said: I hoped you say: use te 60° chisel.... 11ER A55 I get cheap from China - in 4 - 6 weeks.... https://www.ebay.de/itm/10pcs-11ER-A55-SMX30-Threading-turning-carbide-inserts-turning-inserts-11IR-16IR/153190290415?hash=item23aada53ef:g:KpgAAOSwt6Nbpcus This is the system I use I am sure you could get 55 & 60 pitch angles to fit with each other. There is no safety critical element. It is just a speedo cable. You could even lock the threads with a not too strong adhesive. Peter W Quote Link to post Share on other sites
JohnC Posted February 1, 2021 Report Share Posted February 1, 2021 (edited) Quote Making the square hole. You need a 3mm broach Horology is your friend How cool is that! Edited February 1, 2021 by JohnC Quote Link to post Share on other sites
stillp Posted February 1, 2021 Report Share Posted February 1, 2021 23 minutes ago, JohnC said: How cool is that! +1 I think he needs a self-centring four-jaw though. Pete Quote Link to post Share on other sites
RobH Posted February 1, 2021 Report Share Posted February 1, 2021 Or perhaps a rotary broach: Quote Link to post Share on other sites
Z320 Posted February 1, 2021 Author Report Share Posted February 1, 2021 (edited) sadly the Simson speedo output is 1.5 mm squared, probably I reduce the end of a (for example) 8 mm shaft to 6 mm, drill it 4 mm and press it squared down to 3 x 3 mm, that's what Pete mentioned? Edited February 1, 2021 by Z320 Quote Link to post Share on other sites
JohnC Posted February 1, 2021 Report Share Posted February 1, 2021 39 minutes ago, RobH said: Or perhaps a rotary broach Can't you just use a square drill Quote Link to post Share on other sites
Z320 Posted February 5, 2021 Author Report Share Posted February 5, 2021 I ordered the cutting inserts from China, and this weekend I will test to press a 4 mm round drilling to a 3 mm squared hole. Is making the angle drive worth an extra thread or is this too special? Quote Link to post Share on other sites
BlueTR3A-5EKT Posted February 5, 2021 Report Share Posted February 5, 2021 28 minutes ago, Z320 said: I ordered the cutting inserts from China, and this weekend I will test to press a 4 mm round drilling to a 3 mm squared hole. Is making the angle drive worth an extra thread or is this too special? Yes the angle drive construction is worth its own thread or it will end up lost in this forum of knowledge. Peter W Quote Link to post Share on other sites
Z320 Posted February 5, 2021 Author Report Share Posted February 5, 2021 But I do it the way I don't know better, and with a simple crown wheel and pinion, because I can't make a worm.... Perhaps I have some questions and get some help, please...? Quote Link to post Share on other sites
Ian Vincent Posted February 5, 2021 Report Share Posted February 5, 2021 (edited) On 1/31/2021 at 8:45 PM, Z320 said: BSB, what else!?! Why not BSCY? 60° chisels I got in my workshop, but shure not 55°... Ciao. Marco Don’t you just love the myriad different Imperial thread sizes and types? Rgds Ian Edited February 5, 2021 by Ian Vincent Quote Link to post Share on other sites
stillp Posted February 5, 2021 Report Share Posted February 5, 2021 10 minutes ago, Ian Vincent said: Don’t you just love the myriad different Imperial thread sizes and types? Rgds Ian Imagine what it was like before Whitworth! Pete Quote Link to post Share on other sites
BlueTR3A-5EKT Posted February 5, 2021 Report Share Posted February 5, 2021 53 minutes ago, stillp said: Imagine what it was like before Whitworth! Pete Read this book for an insight Sir Joseph Whitworth: The World's Best Mechanician https://www.abebooks.co.uk/products/isbn/9780750916486 Quote Link to post Share on other sites
Ian Vincent Posted February 5, 2021 Report Share Posted February 5, 2021 As a civil engineer who graduated at Manchester University, the name Whitworth was one we were all familiar with. Rgds Ian Quote Link to post Share on other sites
Z320 Posted February 6, 2021 Author Report Share Posted February 6, 2021 (edited) I'm pleased with my first "square drilling" And the cogs from China are also in, they run well on the lathe. Time for the speedo angle drive project Edited February 6, 2021 by Z320 Quote Link to post Share on other sites
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