... fine, and far and away the easiest type to make (assuming you have a lathe, of course). The trick is not to have them too large in diameter, so that they fit between two adjacent rail fixings without getting in the way. A roller gauge turned from 6mm or 8mm bar is plenty large enough (1 /4" or 5/16" dia) in 4mm scale. For use with canted rail in chairs it's important not to make the gauge slots deeper than the rail head. The radiused corners on the rail head easily allow a few degrees of twist to accommodate the cant. For use with soldered construction on rivets or copper laminate, you don't have the chairs to hold the rail upright. So in that case it helps to make the slots the full depth of the rail so that the gauge also serves to hold the rail vertical. This means that a roller gauge for glued chaired construction is not so good for soldered construction, and vice versa. Ideally you need a gauge tool specific for each. ...

... the DXF version number in the exported file, to match the above "junk". At first sight the two files are very similar. Thanks again, Martin. posted: 6 Jan 2016 00:14 from: Martin Wynne Hi Andy, First signs that this might work. A couple of your chairs in Templot's background shapes: 2_051906_110000000.png Templot wouldn't import your DXF file. But it would after I opened it in my old copy of TurboCAD and saved it again. The first task would seem to be to get some radiused corners on these 2D chairs. There is already a dialog for some chair data -- it has been in Templot for about 15 years and never yet used, see real> chairs/ baseplates> chair/ baseplate data... Click the? info buttons for some notes about each dimension. regards, Martin. posted: 6 Jan 2016 01:20 from: Andrew Barrowman Hi Martin, For the sake of drawn appearance you might radius the corners, but for printing at this scale it's a waste of time ...

... Wagon wheels are usually 5" wide, which scales to 1.67mm, so only just wide enough to span the gap. In fact not quite wide enough if you allow for the corner radius on the rail and a chamfer between the face of the wheel and the tread. If you use exact scale wheels you need to make sure not to exceed the specified flangeway gap just in front of the nose of the vee. Here's some stuff I have posted on RMweb a few times:____ The knuckles should be radiused, the knuckle gap being wider than the crossing flangeway gap. Here's a diagram which may help when setting the wing rail knuckles: 2_220535_490000000.png The blue infill shows the theoretical ideal with a sharp bend at K exactly matching the angle of the vee and in line with it. In practice on the prototype it is not possible to make such a sharp bend because of the 1:20 inclination of the rails. Instead, a short curve is used, as shown by the green line, making the knuckle gap wider than ...

... 2.30mm and the wheel is effectively 1.95mm, a difference of 0.35mm. The combination of chamfer and radius reduces that a bit, let's say 0.3mm. So at 1:7 the wheel drop is in effect over 7 x 0.3= 2.1mm. For a wagon wheel at 6mm radius that means a drop of 0.09mm. Adding half of the low nose increases that to 0.14mm or 5 thou. Not much, but enough to be noticeable in bumpy running. The effect is made worse because the combination of chamfer on the wheel and radiused corner on the rail cause the wheel to wedge itself into the space, and need to be dragged out by the couplings, creating much more of a bump than the drop alone. But on longer crossings the effect increases significantly. Suppose you have a long curved crossover needing 1:12 crossings to stay within your radius limit. The wheel drop is then in effect over 12 x 0.3= 3.6mm, and the drop is more than doubled to 0.33mm or 13 thou. With greater wedging effect between the rails. That's ...

... will become a multi-sided polygon. Instead, change the corner dimensions to fit within the overall size. Here you can see that the overall width and depth of the rectangle is 69.8 x 36.8 mm, so clearly corner dimensions of 93.9mm are not going to fit, with the result that it looks like an ellipse: 2_120756_080000000.png You probably want to change the corner size to say 10mm or less. The width and depth of the corners can be set separately, although normally they would both be set the same for a radiused corner. I will look again at how the default sizes for the corners are set when first adding a rounded rectangle. Possibly they should be set as a% of the overall size, not in mm. I think you would find that if you added a much larger one it would look ok. I will write a bit more about editing the outlines of sketchboard items later, but that is definitely not what you want to do here. Thanks for posting the sketchboard file. regards, Martin. posted: 12 ...

... a lot of useful background information in the book for bullhead track generally. Here are some of pictures of a BR(W) switch and crossing: gwr1.jpg gwr2.jpg gwr3.jpg gwr4.jpg gwr5.jpg These pictures show the joggled switch detail. The new product from C&L is I believe the "slab and bracket" design of A chair (under the V-crossing nose) in the bottom picture. Interesting points to note are the characteristic semi-circular inside ends on the slide chairs and check rail chairs (in contrast to the radiused square corners on the other chairs). Chair drawings showing these details are on page 98 of the above book. Notice also that the check rails are one timber position out compared to the standard drawings -- the final check chair is normally in line with the end of the wing rail (diagram on page 36 of the book). regards, Martin. posted: 8 Aug 2007 16:16 from: Paul Boyd Hi Martin I cut and pasted the title from the GW Study Group website I spotted your subtle ...

... need for the flange lubricators often seen on such curves. Generally model curves are much sharper than the prototype, so likewise any coning of the wheels has no effect -- it is the wheel flanges which guide wheels round curves. On straighter track, variations in model axle alignments, variations in rail height, and tolerances on wheel diameter mean that any steering effect from model coning is effectively destroyed. It is easily demonstrated -- turn the flanges off some coned wheels, and try running trains. The rail head has a radiused top, so with or without coning, the wheel makes only a point contact with the inclined rail head until some rail wear has occurred. That is generally a slow process on models, usually resulting more from track cleaning than running trains. In practice the lack of working coning is a good thing. With no differential between the opposite wheels on a fixed axle, it means that one or other wheel is always slipping slightly instead of pure rolling. Which helps to keep wheels and rails clean. If our wheels only ...

... 36 from: Hayfield Matt thanks for that,will try and follow it up John posted: 29 Sep 2013 18:05 from: Martin Wynne Hayfield wrote: What I am looking for is a gauge with a positive connection to the rails but allows for the 1-20 inclination. I have a contact who is willing to turn me a set and I am looking for any advice that is available Hi John, The deeper slot face on the inside in your sketch serves no purpose. The head of bullhead rail is radiused on the corners and will easily turn through the small angle of 3 degrees within a standard roller gauge slot: 2_291255_350000000.png It is only necessary not to make the slot so deep that it engages the rail foot. A slot depth of 1.0mm is about right* for 4mm scale. The chairs hold the rail upright (at 3 degrees, 1:20), so when using functional chairs there is no need for the gauge tool to hold the rail, it is used solely for gauging. *for gauging between the ...

... '. I also came across a rather strange problem. Having inserted a turnout into one of the triple terminus tracks, 413, I clicked on 'tools> make simple crossover'. Instead of making a simple crossover, it always tried to make a ladder crossover with rather odd timbering as below. This happens on all of the three tracks 413, 458 and 450 but nowhere else on the plan. By the way, what is the difference between 'invert handing' and 'swap hand'? exit_timbered.jpg Cheers. Brian Attachment: attach_139_228_arnewood.box 340 posted: 19 Nov 2007 02:19 from: Jim Guthrie While looking through my copies of the RM, I came across this in August, 1963- this was the plan I was thinking of, and I can see that CJF wasn't averse to plagiarising one of his own designs :-) CJF-TERM.JPG I might find the later design, but here are the words and music with the original. I'm sure CJF will waive copyright problems ;-) Jim. posted: 19 Nov 2007 02:57 ...