Andy Reichert Posted November 8, 2014 Share Posted November 8, 2014 I want to fit much longer bogie fixing screws to some of my Bachmann MK1's for a modification project. The existing screws appear to be a machine screw thread, rather than self tapping.. Does anyone know the thread type and size please? Andy Link to post Share on other sites More sharing options...
Baby Deltic Posted November 15, 2014 Share Posted November 15, 2014 No, but you could drill out the bogie pivot hole with. 4.2mm drill and tap it M5. You could then use a standard M5 bolt. Link to post Share on other sites More sharing options...
Andy Reichert Posted November 17, 2014 Author Share Posted November 17, 2014 Thanks, That will work, but I was really hoping for a "drop in". I've made an accessory that I didn't want to have any complicated fitting for. Given how many Bachmann MK1's there must be out in the field, including modified ones on EM and P4 layouts , I can't believe no-one has needed to know the thread. Andy Link to post Share on other sites More sharing options...
Dave Scott Posted November 17, 2014 Share Posted November 17, 2014 Thanks, That will work, but I was really hoping for a "drop in". I've made an accessory that I didn't want to have any complicated fitting for. Given how many Bachmann MK1's there must be out in the field, including modified ones on EM and P4 layouts , I can't believe no-one has needed to know the thread. Andy Just been and looked at my Bachman Bulleid, assume the same pivot, and the thread measures 2.01mm. IT is not BA, too coarse, so I would suggest the thread is M2. Link to post Share on other sites More sharing options...
Andy Reichert Posted November 17, 2014 Author Share Posted November 17, 2014 Thanks a bunch! I'll try that. Metric threads are far less common over here in the US, so acquiring a wide range of test nuts etc., for running comparisons is not as easy. Andy Link to post Share on other sites More sharing options...
Dave Scott Posted November 17, 2014 Share Posted November 17, 2014 Thanks a bunch! I'll try that. Metric threads are far less common over here in the US, so acquiring a wide range of test nuts etc., for running comparisons is not as easy. Andy Andy - we are so used to everything having metric threads here in Europe that it is easy to forget N America still uses imperial. Mind you even here getting M2 screws and nuts would be a challenge as smallest seen in most DIY shops is M3. You would be looking to specialist model shops or specialist screw supplyers. The main issue is do you need to revert to the Bachman screw. If not using a small size imperial screw looks like a posibility. Can you get BA screws. I know its British Association but the screws with Kadee couplers seem to be a BA size, 8BA I believe Link to post Share on other sites More sharing options...
RMweb Premium melmerby Posted November 17, 2014 RMweb Premium Share Posted November 17, 2014 . Mind you even here getting M2 screws and nuts would be a challenge as smallest seen in most DIY shops is M3. Try Maplin: http://www.maplin.co.uk/p/330-part-nut-washer-and-screw-set-n53bu A box of useful metric nuts, screws and washers. Keith EDIT Or online: http://www.rapidonline.com/FFSearchResults.aspx?filterSearchScope=1&filterCategoryPathROOT=Screws+%26+Bolts&followSearch=9954&sourceRefKey=3axEJs5yN&keywords=M2 Link to post Share on other sites More sharing options...
Dave Scott Posted November 17, 2014 Share Posted November 17, 2014 Try Maplin: http://www.maplin.co.uk/p/330-part-nut-washer-and-screw-set-n53bu A box of useful metric nuts, screws and washers. Keith EDIT Or online: http://www.rapidonline.com/FFSearchResults.aspx?filterSearchScope=1&filterCategoryPathROOT=Screws+%26+Bolts&followSearch=9954&sourceRefKey=3axEJs5yN&keywords=M2 Thanks for the pointer - keep forgetting Maplins. I dont think it will help Andy though. Do Maplins trade in US? Link to post Share on other sites More sharing options...
Andy Reichert Posted November 17, 2014 Author Share Posted November 17, 2014 Thanks for the pointer - keep forgetting Maplins. I dont think it will help Andy though. Do Maplins trade in US? We have North West Short Line who still act like traditional model engineering suppliers. I'll get some screws and nuts from them. Cheers Andy Link to post Share on other sites More sharing options...
RMweb Premium melmerby Posted November 17, 2014 RMweb Premium Share Posted November 17, 2014 Can you get BA screws. I know its British Association but the screws with Kadee couplers seem to be a BA size, 8BA I believe I suspect the screw that Kadee employ is actually an American standard size (specified in inches of course) and not 8BA, although they may be a close size and pitch match Keith Link to post Share on other sites More sharing options...
ozzyo Posted November 17, 2014 Share Posted November 17, 2014 Sounds like the nearest that you would get normally in the U.S. is 2-56 the dia is 0.086" (2.18mm). You can get these from Micro Mark. http://www.micromark.com/hex-head-machine-screws-2-56-x-1and2-inch-pkg-of-25,10656.html Not sure about the pitch on them though. OzzyO. Link to post Share on other sites More sharing options...
Il Grifone Posted November 17, 2014 Share Posted November 17, 2014 Unfortunately B.A., metric and American threads are all different. You may require to drill out and retap. 80 thou. is about 2mm so brute force might work, but I don't recommend it. Being made in China, Bachmann threads are probably metric, but since it's an American company (I think - who knows these days?) they could even be American. B.A. is unlikely as they are supposed to be obsolete. Not having any Bachmann coaches myself I don't know. These might be helpful. http://www.kadee.com/htmbord/screws.htm http://en.wikipedia.org/wiki/ISO_metric_screw_thread Link to post Share on other sites More sharing options...
Grovenor Posted November 17, 2014 Share Posted November 17, 2014 I can't believe no-one has needed to know the thread. Well, Bill B's replacement sprung bogies go on with the same screws as supplied, and I have yet to lose one. If you are designing items to fit the Bachman coaches can you not just look at your coach? You will also need to know all the other dimensions of the bogie mounting. No, but you could drill out the bogie pivot hole with. 4.2mm drill and tap it M5. You could then use a standard M5 bolt. We are not talking 0 gauge here, the boss you would be drilling into is only 4 mm diameter. Just been and looked at my Bachman Bulleid, assume the same pivot, and the thread measures 2.01mm. The ones on my Mk 1s measure 1.9 on my calipers but that could just be measurement variation. They are not an M2 thread, much coarser, much more akin to a self tapping thread, but without the usual starting shape. Even so I suspect they are installed by self tapping. To use a proper machine screw you would need to drill and tap for a slightly larger size, M2.5 or the american equivalent. However the coarse thread on the existing screw will hold nmore securely. Regards Keith Link to post Share on other sites More sharing options...
Andy Reichert Posted November 18, 2014 Author Share Posted November 18, 2014 Update today. I tried some M2 and found the same as Keith. The Bachmann screws are smaller dia and about half the tpi. So it looks like a self tapper after all. I'll try to find a US industrial source. I'm intending to add some parts below the bolster, keeping the Bachmann bogies intact. So I need a longer screw to pass through the extra material when the bogies are re-attached. Andy Link to post Share on other sites More sharing options...
ozzyo Posted November 19, 2014 Share Posted November 19, 2014 Hello Andy, would these lag screws from Micro Mark be of any use? http://www.micromark.com/-0-x-3and16-Inch-Miniature-Lag-Screws-Pkg-of-50,8157.html OzzyO. Link to post Share on other sites More sharing options...
11B Posted November 19, 2014 Share Posted November 19, 2014 Andy - we are so used to everything having metric threads here in Europe that it is easy to forget N America still uses imperial. Mind you even here getting M2 screws and nuts would be a challenge as smallest seen in most DIY shops is M3. You would be looking to specialist model shops or specialist screw supplyers. The main issue is do you need to revert to the Bachman screw. If not using a small size imperial screw looks like a posibility. Can you get BA screws. I know its British Association but the screws with Kadee couplers seem to be a BA size, 8BA I believe I've used this company before, http://www.westfieldfasteners.co.uk/ The standard delivery was very fast indeed. No other connection to them just a happy customer. Or of the USA members https://www.boltdepot.com/Default.aspx I didn't use this company, but did exchange a few e-mails with them, and they where very helpful. In fact, as they did not deliver to the UK, it was they who put me onto westfieldfasteners.co.uk Hope this may be of some help to someone. Ian Link to post Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.