AndyID Posted March 2, 2021 Share Posted March 2, 2021 I've been salvaging some old Mainline wheels by replacing the plastic axles with steel and teak electrical insulation. Of course have to quarter them properly so I came up with this. It should work for any wheels. It's really more of a gauge that confirms the quartering is correct rather than a press that's designed for a particular manufacturer's wheels. This is the general idea. The diagram on the left shows that the distance between the edge of the crank pins and a vertical or horizontal tangent to the wheel is equal to the radius of the wheel minus the radius of the crank pin. You can rotate the whole thing through 45 degrees to take advantage of gravity. And here's the result. I made a strip of steel to that dimension for these particular wheels and cut in two. I deliberately made the cut at an angle just to make the point. It does help if one end is square but that's not essential. All that matters is that the two edges are parallel and at the correct distance apart. I'm using a machinist's block but that's not really necessary. Extruded L shape angle aluminium would work or anything else that's really square. The gauge strip could be made from just about anything and the two pieces could be locked together at the bottom on a threaded rod. 4 1 Link to post Share on other sites More sharing options...
RMweb Gold Enterprisingwestern Posted March 2, 2021 RMweb Gold Share Posted March 2, 2021 6 minutes ago, AndyID said: Extruded L shape angle aluminium would work In my experience, (I'm a terminal jig builder!), extruded L shape material, plastic or aluminium, is never exactly 90 degrees. Whilst it may be close enough for things like corners of wagons and buildings where the odd 1 or 2 degrees is neither here nor there, I wouldn't advise using it for something which needs to be spot on such as wheel quartering. I always go for milled angle stock as it usually correct, or cobble something together using 123 blocks. Mike. Link to post Share on other sites More sharing options...
AndyID Posted March 2, 2021 Author Share Posted March 2, 2021 Hi Mike, Whatever is used certainly does need to be tested for square but I have some 1/8" aluminum angle that's spot-on, otherwise I would not have suggested it. Of course steel angle is NBG at all Andy 1 Link to post Share on other sites More sharing options...
RMweb Gold Enterprisingwestern Posted March 2, 2021 RMweb Gold Share Posted March 2, 2021 The amusing thing is that here in Spain wood isn't a suitable construction material, so aluminium replaces it, so one would think it would be of merchantable quality, a forlorn hope as with most things in this country! Mike. Link to post Share on other sites More sharing options...
doilum Posted March 2, 2021 Share Posted March 2, 2021 Is the perfect 90 degrees critical? Surely what is important lid that all wheelsets are the same. 8 Link to post Share on other sites More sharing options...
5050 Posted March 2, 2021 Share Posted March 2, 2021 4 hours ago, doilum said: Is the perfect 90 degrees critical? Surely what is important lid that all wheelsets are the same. What if you're building a Lord Nelson? (I think that's the correct class?!) 1 Link to post Share on other sites More sharing options...
doilum Posted March 2, 2021 Share Posted March 2, 2021 9 minutes ago, 5050 said: What if you're building a Lord Nelson? (I think that's the correct class?!) ? Link to post Share on other sites More sharing options...
5050 Posted March 2, 2021 Share Posted March 2, 2021 (edited) 2 minutes ago, doilum said: ? Weren't they at 60 degrees? Was it was LN's - or possibly another class entirely! Or (as is completely possible) I am in my usual state of complete confusion and it never happened at all....................... Edited March 2, 2021 by 5050 Link to post Share on other sites More sharing options...
doilum Posted March 2, 2021 Share Posted March 2, 2021 1 minute ago, 5050 said: Weren't they at 60 degrees? It was LN's - or possibly another class entirely! Quite possibly. Back to my original comment of the importance of identical "quartering". For a minute you had me thinking there was a class that somehow managed to rotate with deliberately misalignned axles! Link to post Share on other sites More sharing options...
2mm Andy Posted March 2, 2021 Share Posted March 2, 2021 4 minutes ago, 5050 said: Weren't they at 60 degrees? It was LN's - or possibly another class entirely! 135 degrees apparently; https://www.watercressline.co.uk/article.php/29/850-sr-lord-nelson-class-lord-nelson Andy 1 Link to post Share on other sites More sharing options...
AndyID Posted March 2, 2021 Author Share Posted March 2, 2021 Or 120 for a three cylinder but if you are driving it with an electric motor the angle for best mechanical advantage is 90 degrees. 3 Link to post Share on other sites More sharing options...
AndyID Posted March 2, 2021 Author Share Posted March 2, 2021 12 hours ago, doilum said: Is the perfect 90 degrees critical? Surely what is important lid that all wheelsets are the same. Yes, making them all the same is definitely required. Have you tried making them all 180 degrees? 2 Link to post Share on other sites More sharing options...
Pete the Elaner Posted March 3, 2021 Share Posted March 3, 2021 20 minutes ago, AndyID said: Yes, making them all the same is definitely required. Have you tried making them all 180 degrees? I doubt it matters on a model where the valve gear is cosmetic. It is not like you can see both sides at the same time, although is is nice to know that one side is leading by the correct angle. As long as all driving wheels are consistent with each other, the loco should run smoothly. 1 Link to post Share on other sites More sharing options...
AndyID Posted March 3, 2021 Author Share Posted March 3, 2021 1 hour ago, Pete the Elaner said: I doubt it matters on a model where the valve gear is cosmetic. It is not like you can see both sides at the same time, although is is nice to know that one side is leading by the correct angle. As long as all driving wheels are consistent with each other, the loco should run smoothly. Yes, the valve gear is entirely cosmetic but the coupling rods are 100% functional (typically) and they work best at 90 degrees. They cannot work at 180 degrees, or zero degrees for that matter. 2 Link to post Share on other sites More sharing options...
hobbyhorse Posted March 3, 2021 Share Posted March 3, 2021 My 7mm version for quartering. Simon 2 3 Link to post Share on other sites More sharing options...
doilum Posted March 3, 2021 Share Posted March 3, 2021 9 hours ago, AndyID said: Yes, making them all the same is definitely required. Have you tried making them all 180 degrees? I think that is the one number that won't work. Likely to lock solid. 2 Link to post Share on other sites More sharing options...
harry lamb Posted March 3, 2021 Share Posted March 3, 2021 I did try the GW wheelpress, the 'Deluxe' Hamblings pattern, but I found a little bit of 'slop' in the crankpin slot for 14BA bolts and the bolts themselves are easily moved out of line. So, I made myself a 'quartering TEST jig' set to around 90 degrees 'ish' for crankpin setting and it works a treat! As I only use push on wheelsets, Ultrascale and AGW plus what I have got left of the 'Exactoscale' jobs, to CHECK the crankpin wheel settings. Now, being a pragmatic sort of Herbert I don't really care if the cranks on my model steam engines don't match the prototype because neither one my two eyes are on its own flexible stem enabling me to see both sides of the locomotive at work simultaneously so I am quite happy to watch my engines run up and down the track one side at a time be it LH or RH leading with crank settings 85, 88 or 95! The beauty of it is that if the jig is out of 'kilter' then every set of completed wheel, axles and bearings that have passed through the jig will be exactly the same and that's the principal I have adhered to for the last 45 years in 18.83mm. gauge with not a single problem. Pictures of the jig, built from scrap have been posted on this forum previously. Somewhere! 3 Link to post Share on other sites More sharing options...
AndyID Posted March 3, 2021 Author Share Posted March 3, 2021 12 hours ago, doilum said: I think that is the one number that won't work. Likely to lock solid. Not the only one. Zero is just as bad In theory any angle other than zero or 180 should work according to the geometry but the further the angle is from 90 in either direction the greater the friction at the coupling rod bearings. As angles approach zero or 180 there is so much friction that's it's impossible to start from some positions. It's going to depend a lot on the type of bearings of course but it's possible Maunsell was around the practical limit with 135 (which is equivalent to 45). Link to post Share on other sites More sharing options...
RMweb Gold Enterprisingwestern Posted March 4, 2021 RMweb Gold Share Posted March 4, 2021 21 hours ago, harry lamb said: neither one my two eyes are on its own flexible stem enabling me to see both sides of the locomotive at work simultaneously There was me thinking that was a pre-requisite of 18.83 modelling! Mike. Link to post Share on other sites More sharing options...
RMweb Gold Captain Kernow Posted March 9, 2021 RMweb Gold Share Posted March 9, 2021 On 04/03/2021 at 08:01, Enterprisingwestern said: There was me thinking that was a pre-requisite of 18.83 modelling! Mike. No, I think you were thinking of the third (or even fourth) hand! 1 Link to post Share on other sites More sharing options...
RMweb Gold Captain Kernow Posted March 9, 2021 RMweb Gold Share Posted March 9, 2021 On 03/03/2021 at 10:44, harry lamb said: Pictures of the jig, built from scrap have been posted on this forum previously. Somewhere! Oh, now that sounds very interesting indeed! I have no idea how to search for an individual photo, so may I respectfully request, if possible, that the photo(s) could be re-posted, please? Many thanks. Link to post Share on other sites More sharing options...
RMweb Gold Enterprisingwestern Posted March 9, 2021 RMweb Gold Share Posted March 9, 2021 1 minute ago, Captain Kernow said: No, I think you were thinking of the third (or even fourth) hand! Don't complicate matters even further, I have all on controlling two hands and a foot when using the RSU! Mike. 1 Link to post Share on other sites More sharing options...
RMweb Gold Captain Kernow Posted March 9, 2021 RMweb Gold Share Posted March 9, 2021 3 minutes ago, Enterprisingwestern said: Don't complicate matters even further, I have all on controlling two hands and a foot when using the RSU! Ah yes, using feet, what a good idea. I shall just enroll for a yoghurt yoga class first! 1 Link to post Share on other sites More sharing options...
harry lamb Posted March 10, 2021 Share Posted March 10, 2021 Quartering TEST jigs. Adjustable to accept 'Exactoscale' wheels with 'lube channels' in stub axle ends and 1/8" standard U/S and AGW plain axles. Once wheels and crank pins are lined up they are pressed home in whatever device you favour and very rarely shift. If so final adjustment is straight forward and can be rechecked before final fitting. Only suitable for fully fitted out wheelsets c/w bearings and gearboxes. 1 Link to post Share on other sites More sharing options...
AndyID Posted March 10, 2021 Author Share Posted March 10, 2021 1 hour ago, harry lamb said: Quartering TEST jigs. Adjustable to accept 'Exactoscale' wheels with 'lube channels' in stub axle ends and 1/8" standard U/S and AGW plain axles. Once wheels and crank pins are lined up they are pressed home in whatever device you favour and very rarely shift. If so final adjustment is straight forward and can be rechecked before final fitting. Only suitable for fully fitted out wheelsets c/w bearings and gearboxes. Very nice but isn't it a bit complicated? And I think it will only work for one axle diameter and one crank pin diameter. The version I posted will work for any axle diameter and any crank pin diameter. Link to post Share on other sites More sharing options...
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