Ravenser Posted October 14, 2009 Share Posted October 14, 2009 You should have to alter the wing rails to sort all the problems and I didn't want anyone to think otherwise. I do however agree that is can't really be fixed unless you use something like Tillig points instead which I believe are a bit tighter in their standards? If Peco were to sort out their check gauge they would need to do it at the wing rails as well as the check rails. Though if this is any more likely than giving a UK sleepering im not so sure butlets not go there! Hornby set track seems even worse than Peco and they do seem to try and hold the wheel on the flange through the crossing. There can be no obligation (moral or otherwise) to do the impossible. Nor is there any obligation to tell anyone else to do the impossible. If you can fix the check rail but not the wing rail that's all you can do... If you'd said that not all the issues with Peco can be fixed by altering the check rail (and in fact the other issues arean't fixable) , I'd not have disputed the point further Tillig actually use slightly wider flangeways than Peco Streamline..... Link to post Share on other sites More sharing options...
Guest jim s-w Posted October 14, 2009 Share Posted October 14, 2009 Chaps I think you both agree that fixing the peco points isn't an option. I wonder if Peco might consider reducing the flangeways on their forthcoming concrete track? (Assuming it still is forthcoming). As that would give a better point for modern wheels. You could always spray them brown if you wanted wood. I know there are lots of differences but most people seem happy to use Peco FB pointwork on little rural branchlines anyway. As long as it worked better would most people care? Cheers Jim Link to post Share on other sites More sharing options...
Ravenser Posted October 15, 2009 Share Posted October 15, 2009 Chaps I think you both agree that fixing the peco points isn't an option. I wonder if Peco might consider reducing the flangeways on their forthcoming concrete track? (Assuming it still is forthcoming). As that would give a better point for modern wheels. You could always spray them brown if you wanted wood. I know there are lots of differences but most people seem happy to use Peco FB pointwork on little rural branchlines anyway. As long as it worked better would most people care? Cheers Jim Jim: I would very much hope they will. Since the clientele for this would be exclusively modern image, most of us have replaced our pre 2000 Hornby stuff and we all know about Ultrascale rewheeling packs, I really can't see any credible reason not to. However I think it would help a lot if there were some support or pressure for this through DEMU channels - DEMU does after all represent the target market for this product Link to post Share on other sites More sharing options...
Guest jim s-w Posted October 15, 2009 Share Posted October 15, 2009 Hi Rav I wouldn't know as I am not a member. I would hope so. Cheers Jim Link to post Share on other sites More sharing options...
Il Grifone Posted October 21, 2009 Share Posted October 21, 2009 Not sure this is right . First clarification - there are two DOGA standards - OO Fine and OO Intermediate. The practical reality is that most people building their own track use OO Intermediate not OO Fine, and it's a little frustrating to see it brushed over as if OO Intermediate does not exist and OO Fine is the only standard.... The OO Intermdiate back-to-back figure is 14.4mm +/-0.05mm Second clarification - The distance from Wing rail to opposite running rail (or from check rail to running rail at the frog) must be [trackgauge minus flangeway] . Thus in the case of OO Intermediate this would be 16.5mm -1.25mm = 15.25mm [ for the sake of good order the OO Intermediate track standard actually sets a nominal value of 1.20mm with a tolerance of +/-0.05mm . I.e. any flangeway between 1.15mm and 1.25mm is within the standard . Since BRMSB roller gauges for 1.25mm flangeway are readily available from several sources, the practical reality is that that is what people are likely to use to build track. There are a lot of layouts out there with such track, and they are (just) compliant with the DOGA OO Intermediate standard] Third clarification: A proper NMRA RP25-110 wheelset will not "drop in" to a 1.25mm flangeway. The limit at which that occurs is >1.27mm (see the NMRA's standards where that is set as the maximum width of the crossing flangeway) The nominal "front to back" will be 14.5+0.5mm = 15.0mm (Il griffon's Hornby case, assuming that these values are actually achieved precisely) or 14.4mm + 0.7mm = 15.1mm (RP25/100 , quoted to 1 decimal place - Bachmann in theory) . In practice the Bachmann factory has manufacturing tolerances on wheelsets that are a good deal more than 0.1mm on back to back. Hence the actual values from Bachmann wheelsets vary much more than the difference between their nominal standard and Hornby's nominal standard If the gauge is 16.5mm , and the front-to-back is 15.0mm , then the difference is 1.5mm - and the tread must be more than 1.5mm wide to stay on the running rail. 2.0mm tread should be fine Sorry I had no intention of "brushing over" the DOGA intermediate standard, it's just something of which I'm of which I'm not 'au fait'. (They are basically NMRA, if I'm not wrong?). I was trying to answer the query re Hornby/Bachmann wheels dropping into the crossing gap on code 100 (presumably Peco). This is due to slack tolerances and can only be solved by tightening these up (New check and wing rails with smaller flangeways) or bodging a fill in so that the wheels run on their flanges. The third, wider wheel, option is precluded by existing wheels. All the Hornby wheels I've measured (vernier) have been as quoted (rolling stock wheels). (Back to back I can't speak for, as I've moved them all out to 16.5 mm) I seem to remember seeing a Hornby advertisement quoting these dimensions some time ago. Link to post Share on other sites More sharing options...
RMweb Premium Gary H Posted October 22, 2009 RMweb Premium Share Posted October 22, 2009 Can I pose a question please gents. What is the issue with Peco S&C? When I junked my EM stuff for H0 I was abit worried and sceptical about the performance of my impending Code 83 Peco gear but I'm happy to say that the wheels I have on all my H0 stock pass over the common crossings of Peco points as smooth as silk and perfectly seamless. Ofcourse the flangeways are overscale, they look to me the same as what they are on their Code 75 stuff, but the performance of their points has been 100% for me and the stock I use over them. Just curious. Link to post Share on other sites More sharing options...
Ravenser Posted October 23, 2009 Share Posted October 23, 2009 Can I pose a question please gents. What is the issue with Peco S&C? When I junked my EM stuff for H0 I was abit worried and sceptical about the performance of my impending Code 83 Peco gear but I'm happy to say that the wheels I have on all my H0 stock pass over the common crossings of Peco points as smooth as silk and perfectly seamless. Ofcourse the flangeways are overscale, they look to me the same as what they are on their Code 75 stuff, but the performance of their points has been 100% for me and the stock I use over them. Just curious. The issue is that Peco code83line is made to pukka NMRA track standards, whereas the code 75 flangeways are at least 0.15mm wider (and I'd be interested to know what the check flangeway is - it may be quite close to the EM value.... I think the NMRA standard mandates asymmetric flangeways [one wider than the other]but frankly the data sheet is not exactly clear. it may be implicit in the figures but they don't exactoly make it explicit ) As you say, tighten up the flangeways from the old Peco values and RTR 16.5mm gauge works perfectly Link to post Share on other sites More sharing options...
Brian Harrap Posted November 1, 2009 Share Posted November 1, 2009 All very interesting stuff. But under the 'Harrap talks twaddle' banner may I toss this observation into the melting pot? Whereas accepting that with properly designed and built crossing vees and matching wheel standards etc etc the actual angle will not effect the drop that we're all so keen to avoid, it has to be noted that on a 90deg crossing there is no support at all for a tyre of any width while it is going over the gap, however large or small, so it must drop here. The conundrum is, at which angle between 90 (must drop) and an angle that is so that there is no drop, does the one state of affairs change to the other. Odd ain't it, Regards Brian. Link to post Share on other sites More sharing options...
RMweb Gold martin_wynne Posted November 1, 2009 RMweb Gold Share Posted November 1, 2009 The conundrum is, at which angle between 90 (must drop) and an angle that is so that there is no drop, does the one state of affairs change to the other. Hi Brian, The situation changes when the crossing angle is so short that the width across the gap in front of the vee nose, measured square to one rail, can no longer be approximated as two flangeway gaps. But in that case the length of the gap to be crossed is quite short. So the amount of drop is very small, at least on the prototype. In a 90-degree crossing, a wheel of 3ft diameter crossing a gap of one flangeway (1.3/4") will drop by only 21 thou (0.5mm) into the gap. That's still enough to create a bump, and such crossings are prone to rapid wear and need frequent maintenance. In 4mm/ft scale that's a drop of only about a 1/4 of a thou! Less than the typical misalignment at any rail joint. But in a model other than P4, etc, the wider flangeway gap causes a more pronounced bump. regards, Martin. Link to post Share on other sites More sharing options...
Brian Harrap Posted November 3, 2009 Share Posted November 3, 2009 Hi Brian, The situation changes when the crossing angle is so short that the width across the gap in front of the vee nose, measured square to one rail, can no longer be approximated as two flangeway gaps. But in that case the length of the gap to be crossed is quite short. So the amount of drop is very small, at least on the prototype. In a 90-degree crossing, a wheel of 3ft diameter crossing a gap of one flangeway (1.3/4") will drop by only 21 thou (0.5mm) into the gap. That's still enough to create a bump, and such crossings are prone to rapid wear and need frequent maintenance. In 4mm/ft scale that's a drop of only about a 1/4 of a thou! Less than the typical misalignment at any rail joint. But in a model other than P4, etc, the wider flangeway gap causes a more pronounced bump. regards, Martin. Thank you Martin, I guess I can live with a 1/4 thou' drop, Brian. Link to post Share on other sites More sharing options...
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