bluestag Posted May 13, 2015 Share Posted May 13, 2015 I've wandered away from 4mm where I am used to Gibson's crankpins being screwed in from the back or Sharman's moulded in place (nice!) I'm building a 7mm loco using Slater's wheels and was astonished to see that the crankpins (which are simple bolts) slide into the holes moulded in the wheel. I just don't get it. How does one tighten up the crankpin nuts if the crankpin is not restrained? Link to post Share on other sites More sharing options...
ozzyo Posted May 13, 2015 Share Posted May 13, 2015 You have a few options, Glue the 12BA screw in place in the wheel. The same as above and then use a staple across the slot in the screw. Tap the wheel and the crank pin bush 10BA, then after sorting the bush to the correct length lock-tight them in place. Or come up with another idea. OzzyO. Link to post Share on other sites More sharing options...
bluestag Posted May 14, 2015 Author Share Posted May 14, 2015 You have a few options, Glue the 12BA screw in place in the wheel. The same as above and then use a staple across the slot in the screw. Tap the wheel and the crank pin bush 10BA, then after sorting the bush to the correct length lock-tight them in place. Or come up with another idea. OzzyO. Yeah, I am still in Los Angeles and 10BA steel bolts are thin on the ground.... I have pondered the staple. I am just surprised that a product that otherwise is so well thought out would leave me hanging here. Link to post Share on other sites More sharing options...
JeffP Posted May 14, 2015 Share Posted May 14, 2015 There's a guy here in the UK will post you some steel BA screws, whatever length you want. Found him in one of the Modelling mags, based near Gainsborough.......can't think of the name of the company at the mo, though. Link to post Share on other sites More sharing options...
Pete Harvey Posted May 14, 2015 Share Posted May 14, 2015 Order what you need here. https://www.eileensemporium.com/index.php?option=com_virtuemart&page=shop.browse&category_id=9&Itemid=9 Link to post Share on other sites More sharing options...
Marshall5 Posted May 14, 2015 Share Posted May 14, 2015 I've used Slaters 12BA crankpin screws as supplied without a problem other than you have to be careful that the screw is absolutely perpendicular to the wheel face. I've not had one unscrew but it might be worth using a bit of 'nut-lock' or even nail varnish as 'belt and braces' or 'belt and suspenders' as you might say. I've also used the method described by Ozzy tapping the bush 10BA drilling out and countersinking the wheel back but I wouldn't want to do it without a drill press. This method does make a more robust job. As you are in the U.S. getting hold of 10BA screws and taps is difficult but you could substitute No 1 screws as the tapping size is drill #53 whereas 10BA is only slightly smaller with a tapping size of #54. When I'm in Boise I can get a tap and drill set in U.S. sizes from the local hobby store although I usually keep a supply of B.A. sizes on my bench there. Hope this helps. Ray. Link to post Share on other sites More sharing options...
bluestag Posted May 14, 2015 Author Share Posted May 14, 2015 Order what you need here. https://www.eileensemporium.com/index.php?option=com_virtuemart&page=shop.browse&category_id=9&Itemid=9 Thanks, Eileen is well stocked, indeed. I'd like a recipe for making do with what is provided. There must be hundreds or thousands of locos built successfully with the Slater's wheels with the provided crankpins. Apparently one glues and then staples the pin. Which is rather a lot of work but compared to turning up my own bushes for larger pins is not so much. I think. Link to post Share on other sites More sharing options...
ozzyo Posted May 14, 2015 Share Posted May 14, 2015 or you could use an American size of screw and tap that is about the same size as a 10BA size? (Tapping size 1.4mm or 0.055" or what that equals in a No. size) To tap out all of the parts and still use the crank pin bushes that are supplied. OzzyO. Link to post Share on other sites More sharing options...
Marshall5 Posted May 15, 2015 Share Posted May 15, 2015 or you could use an American size of screw and tap that is about the same size as a 10BA size? (Tapping size 1.4mm or 0.055" or what that equals in a No. size) To tap out all of the parts and still use the crank pin bushes that are supplied. OzzyO. Must be an echo round here LOL! See post 6. Cheers, Ray. Link to post Share on other sites More sharing options...
bluestag Posted May 15, 2015 Author Share Posted May 15, 2015 Must be an echo round here LOL! See post 6. Cheers, Ray. #1 steel fasteners and taps are as rare as BA in this market. Might as well stick to Brit threads. Link to post Share on other sites More sharing options...
bluestag Posted June 24, 2015 Author Share Posted June 24, 2015 Apparently there is an aftermarket crankpin system suitable for Slater's wheels made by Derek Mundi that features a bush that passes thru the wheel and is secured from the back with a screw and retains the coupling rods with another screw. Has anyone any experience with this product and would you care to comment on its efficacy? Link to post Share on other sites More sharing options...
meil Posted June 24, 2015 Share Posted June 24, 2015 Yeah, I am still in Los Angeles and 10BA steel bolts are thin on the ground.... I have pondered the staple. I am just surprised that a product that otherwise is so well thought out would leave me hanging here. Which is why the S7 wheels produced by Slaters has an integral metal insert to take the crank-pin. Link to post Share on other sites More sharing options...
Sandy Harper Posted June 24, 2015 Share Posted June 24, 2015 Apparently there is an aftermarket crankpin system suitable for Slater's wheels made by Derek Mundi that features a bush that passes thru the wheel and is secured from the back with a screw and retains the coupling rods with another screw. Has anyone any experience with this product and would you care to comment on its efficacy? I have used these and found them to be excellent. Adds to the cost of your wheel though, but a well engineered product. You will need a drill press , and the correct size drill, to ensure the hole, to accept the crank, is square to the wheel and a tight fit. Regards Sandy Link to post Share on other sites More sharing options...
Kenton Posted June 24, 2015 Share Posted June 24, 2015 Never employed the staple idea - simply too much faff. Tapping - likewise, but probably the right way to do it. glue them in and thread lock the nut. Link to post Share on other sites More sharing options...
northcroft62 Posted June 24, 2015 Share Posted June 24, 2015 Gladiator models do scewed crankpin bushes to suit Slaters 7mm wheels, however they are at present being bought by another proprieter. Donald Link to post Share on other sites More sharing options...
ian@stenochs Posted June 24, 2015 Share Posted June 24, 2015 Hi I have used the standard item and never had a problem. I counterbore the back to take the head of the screw and don't use glue of any kind. When the nut is tightened up nothing moves. On locos with outside gear I use a 10 ba screw on the axle with a return crank with the bush threaded and reversed and the crank soldered to it. Ian. Link to post Share on other sites More sharing options...
ozzyo Posted June 24, 2015 Share Posted June 24, 2015 Have a look at these links. http://www.micromark.com/tap-1-72nf,6518.html Try this one for the screws. http://www.micromark.com/flat-head-machine-screws-1-72-x-1and2-inch-pkg-of-25,10636.html OzzyO. Link to post Share on other sites More sharing options...
bluestag Posted June 26, 2015 Author Share Posted June 26, 2015 Have a look at these links. http://www.micromark.com/tap-1-72nf,6518.html Try this one for the screws. http://www.micromark.com/flat-head-machine-screws-1-72-x-1and2-inch-pkg-of-25,10636.html OzzyO. I don't think I trust brass screws for crankpins. #1 in steel is hard to find. Link to post Share on other sites More sharing options...
ozzyo Posted June 26, 2015 Share Posted June 26, 2015 I don't think I trust brass screws for crankpins. #1 in steel is hard to find. I don't think brass is as bad as you think, I've just had a look at the tensile strength of both of them. Brass 200+ MPa Steel 247 MPa MPa = Mega-pascals. OzzyO. Link to post Share on other sites More sharing options...
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