Printed F/B track (filament printer)

[AndyID]

I've been mucking about trying different ways of printing UK-esque flat-bottom track. One reason for doing this is because I have rather a lot of F/B rail

 

The base of the rail varies slightly, something like 4 thou (0.1mm) between max and min which does not sound like much but it creates a bit of a problem with printed methods of securing the rail to the timbers. Printed baseplates/clips/chairs etc. are not very flexible (this applies to FDM and resin prints) and if I print them "tight" they are liable to break when the rail is inserted. If I print them to accommodate the maximum width rail minimum width rail is not secured properly and won't hold gauge. (A lot of this applies to bullhead rail too.)

 

Here's a sample in cruel magnification. At this stage the fixings are quite incomplete and not intended to represent anything in particular. It's just a test to see if it's possible to handle the variations in rail width.

 

 

The rails in this sample are at the two extremes of width. The "clips" barely overlap the flat-bottom flange but both rails are quite secure.

 

If you have not already guessed the rail is effectively being "woven" between the clips. The clips on the outside tend to push the rails towards the center while the clips on the inside do the opposite. The amount of defection is very small but it's just enough to maintain constant pressure between the clips and the rail. I have to do more investigating but it feels like there is enough lateral flex in the printed base to equalize the forces so that the pressure is the same on both rails even though they are not the same width, but that might be an illusion.

 

Clearly more bits have to be added/subtracted to make these represent real prototypes but I'm hoping that will mostly be cosmetic.

[Enterprisingwestern]

 

I f you fancy printing bullhead and flat bottom rail as a stand alone, I'll have a few yards off you, as would a few others I suspect, it's a lot lighter alternative to N/S rail for wagon loads such as the sturgeon, borail, etc.

 

Mike.

[AndyID]

31 minutes ago, Enterprisingwestern said:

 

I f you fancy printing bullhead and flat bottom rail as a stand alone, I'll have a few yards off you, as would a few others I suspect, it's a lot lighter alternative to N/S rail for wagon loads such as the sturgeon, borail, etc.

 

Mike.

 

Hi Mike,

 

Am I right thinking you are interested in realistic 3D printed track panels to use as wagon loads? That's certainly possible and for the best detail/accuracy it would probably be best if they were printed in resin.

 

I'm messing about with filament printing and N/S rail for working track and most likely points/turnouts which is a bit different but I can knock out a 3D model for you if you are interested. I'm in the US and you would want to find a place that can print it near you.

 

Andy

[Stubby47]

Presumably you could print these at 00, EM or P4 widths ?

[Enterprisingwestern]

7 hours ago, AndyID said:

 

Hi Mike,

 

Am I right thinking you are interested in realistic 3D printed track panels to use as wagon loads? That's certainly possible and for the best detail/accuracy it would probably be best if they were printed in resin.

 

I'm messing about with filament printing and N/S rail for working track and most likely points/turnouts which is a bit different but I can knock out a 3D model for you if you are interested. I'm in the US and you would want to find a place that can print it near you.

 

Andy

 

Accurate track panels (45', 60' etc) would be good,but I was thinking of just lengths of rail.

 

Mike.

[AndyID]

19 hours ago, Stubby47 said:

Presumably you could print these at 00, EM or P4 widths ?

 

Certainly and this would work for larger scales too. It might work for N gauge but that could be pushing it a bit.

 

I'm mainly interested in making turnouts but I might make some plain track too. I don't plan to sell any of this but I will give the 3D model files to anyone who wants to take a shot at printing them for their own use. However, I'm not able to provide support if they run into any problems.

[AndyID]

12 hours ago, Enterprisingwestern said:

 

Accurate track panels (45', 60' etc) would be good,but I was thinking of just lengths of rail.

 

Mike.

 

Thanks for the clarification Mike. That's a bit beyond the capability of a filament printer for 00 scale rail. Depending on the particular material It should just about work for resin prints but they could be a bit expensive. Would the rails have to be individual rails or would a print of a bundle of rails work? That might help to keep the cost down but the snag is the loads on each wagon would be identical. Would anyone care/notice?

 

 

[Enterprisingwestern]

3 hours ago, AndyID said:

 

Thanks for the clarification Mike. That's a bit beyond the capability of a filament printer for 00 scale rail. Depending on the particular material It should just about work for resin prints but they could be a bit expensive. Would the rails have to be individual rails or would a print of a bundle of rails work? That might help to keep the cost down but the snag is the loads on each wagon would be identical. Would anyone care/notice?

 

 

 

As, generally speaking, rail bundles are similar when machine/crane loaded new for delivery I don't think that would matter, it's only when they get manually loaded on a working site that they would vary.

 

Mike.

[martin_wynne]

17 hours ago, Enterprisingwestern said:

Accurate track panels (45', 60' etc) would be good,but I was thinking of just lengths of rail.

 

 

Hi Mike,

 

I have been able to print a reasonable approximation to individual 4mm rails on my filament printer:

 

 

 

I gave up on the conventional approach of slicing a 3D STL file and generated the gcode directly in Templot. Only tried bullhead so far, but it should work equally well in flat-bottom.

 

The snag is that the rail length is limited by the work area of my printer to 200mm, so it can't do 60ft rails. I can post the gcode files if anyone has a larger FDM (filament) printer and is happy to edit the gcode for the longer lengths and flat-bottom. Or I could add the functions to the release version of Templot -- I hadn't though of using them for wagon loads. They are very light and flexible.

 

cheers,

 

Martin.

Edited February 26, 2022 by martin_wynne

[Enterprisingwestern]

 

That looks excellent Martin, just what I was thinking of.

The problem is that I am at the bottom end of the computer savvy spectrum and am in the hands of others to actually provide something, so if anyone is willing to give it a go, I am a willing sponsor.

 

Mike.

[martin_wynne]

p.s. Mike,

 

It would be possible to do 60ft rails diagonally across the printer build plate.

 

Those trials were done 2 years ago using a 0.6mm nozzle. I would need to revisit them for flat-bottom rail and a standard 0.4mm nozzle. I will see what's possible.

 

cheers,

 

Martin.

[AndyID]

A bit more like the real thing although I will make some more adjustments. It's surprising (to me anyway) that I can get away with so little overlap over the rail bottom. It could be because the filament is quite hard and not very flexible.

 

 

This is 16.2 mm gauge. The rail is really a bit low profile for UK F/B. It's 72 thou tall (Code 72)

[Enterprisingwestern]

 

To my untrained eye that looks quite promising.

Bullhead rail is code 70 in the finer scales, so I for one wouldn't argue about 2 thou!

 

Mike.

[Andy Reichert]

Code 82 FB is only proportionally to scale at 18.83 mm. If your track gauge is 16.5 mm then code 70 looks the correct height in relation to the gauge. Of course to maintain the same scale reduction (and visual impression) for 16.5 mm gauge, you really should shrink the sleeper size and  spacing too.

 

Andy

 

[AndyID]

3 hours ago, Andy Reichert said:

Code 82 FB is only proportionally to scale at 18.83 mm. If your track gauge is 16.5 mm then code 70 looks the correct height in relation to the gauge. Of course to maintain the same scale reduction (and visual impression) for 16.5 mm gauge, you really should shrink the sleeper size and  spacing too.

 

Andy

 

 

Hi Andy,

 

You can print yours to any scale/dimensions that happen to float your boat. If you send me the details I'll post an STL file and you can try printing it yourself.

 

BTW, that's your rail I'm using

 

Andy

[Andy Reichert]

1 hour ago, AndyID said:

 

Hi Andy,

 

You can print yours to any scale/dimensions that happen to float your boat. If you send me the details I'll post an STL file and you can try printing it yourself.

 

BTW, that's your rail I'm using

 

Andy

Thanks,

 

 

I'm still using filaments that are are organic and grow on trees. . . from files created eons ago

 

Around 350 Million years perfecting . . . and still counting

 

Andy

 

 

 

[AndyID]

39 minutes ago, Andy Reichert said:

Thanks,

 

 

I'm still using filaments that are are organic and grow on trees. . . from files created eons ago

 

Around 350 Million years perfecting . . . and still counting

 

Andy

 

 

 

 

You might try moving up to some 21st Century stuff. PLA is made from corn starch

[AndyID]

58 minutes ago, Andy Reichert said:

Thanks,

 

 

I'm still using filaments that are are organic and grow on trees. . . from files created eons ago

 

Around 350 Million years perfecting . . . and still counting

 

Andy

 

 

 

 

Pity you can't scale the grain

 

[martin_wynne]

On 28/02/2022 at 07:23, Enterprisingwestern said:

 

To my untrained eye that looks quite promising.

Bullhead rail is code 70 in the finer scales, so I for one wouldn't argue about 2 thou!

 

Mike.

 

Hi Mike,

 

At 4mm/ft (00, EM, P4):

 

BS-95R Bullhead rail (by far the most common bullhead) scales to Code 75.

 

BS-85R Bullhead rail (occasionally used for branch lines and sidings) scales to Code 72.

 

BS-113A Flat-bottom rail scales to Code 82.

 

cheers,

 

Martin.

[Enterprisingwestern]

28 minutes ago, martin_wynne said:

 

Hi Mike,

 

At 4mm/ft (00, EM, P4):

 

BS-95R Bullhead rail (by far the most common bullhead) scales to Code 75.

 

BS-85R Bullhead rail (occasionally used for branch lines and sidings) scales to Code 72.

 

BS-113A Flat-bottom rail scales to Code 82.

 

cheers,

 

Martin.

 

Knowing full well that fb rail is 75 thou, where did I get 70 thou from?

Thanks for the correction.

I'm blaming raging senility!

 

Mike.

[martin_wynne]

7 minutes ago, Enterprisingwestern said:

 

Knowing full well that fb rail is 75 thou, where did I get 70 thou from?

 

 

Hi Mike,

 

At 4mm/ft scale:

 

For most standard gauge UK track, FB rail should be code 82.

 

Peco use code 75 and code 100 FB rail for their track, but neither is correct at 4mm/ft.

 

Code 75 doesn't match any common flat-bottom rail, the nearest being BS-90 FB rail (code 74), used on narrow-gauge lines, light railways, industrial sidings, mines and quarries.

 

Code 100 is larger than any standard UK FB rail.

 

cheers,

 

Martin.

[Enterprisingwestern]

5 minutes ago, martin_wynne said:

 

Hi Mike,

 

At 4mm/ft scale:

 

For most standard gauge UK track, FB rail should be code 82.

 

Peco use code 75 and code 100 FB rail for their track, but neither is correct at 4mm/ft.

 

Code 75 doesn't match any common flat-bottom rail, the nearest being BS-90 FB rail (code 74), used on narrow-gauge lines, light railways, industrial sidings, mines and quarries.

 

Code 100 is larger than any standard UK FB rail.

 

cheers,

 

Martin.

 

I give in.

I meant to put bh.

The nurse is on her way with the tablets!

 

Mike.

[AndyID]

20 minutes ago, Enterprisingwestern said:

 

Knowing full well that fb rail is 75 thou, where did I get 70 thou from?

Thanks for the correction.

I'm blaming raging senility!

 

Mike.

 

I don't think he did! FB rail can be any old size you care to pick

 

Now look, I'm getting more than a bit PO'd by all this complete sillyness about scale/gauge/rail/wood. This thread was intended to be about how you might print your own track and turnouts with a FDM printer. If nobody is really interested in that and they want to argue about those other things they  might want to start another topic.

[martin_wynne]

19 minutes ago, AndyID said:

 

I don't think he did! FB rail can be any old size you care to pick

 

Now look, I'm getting more than a bit PO'd by all this complete sillyness about scale/gauge/rail/wood. This thread was intended to be about how you might print your own track and turnouts with a FDM printer. If nobody is really interested in that and they want to argue about those other things they  might want to start another topic.

 

Hi Andy,

 

But you were the one who said "The rail is really a bit low profile for UK F/B. It's 72 thou tall (Code 72)", so starting the rail discussion.

 

The problem is that you are posting on a UK forum, where the commonly available flat-bottom rails are code 75, code 82, code 100. So those are the rails most RMweb members are likely to want to print for. The foot widths differ, so your STL files are likely to need adjustment to suit. You have said that the clips overlap the rail foot only marginally.

 

p.s. on a Forum threads go wherever the contributors take them. To start a topic on which you have control of the content, use the Blogs section. That's what it's there for.

 

cheers,

 

Martin.

[AndyID]

5 minutes ago, martin_wynne said:

 

Hi Andy,

 

But you were the one who said "The rail is really a bit low profile for UK F/B. It's 72 thou tall (Code 72)", so starting the rail discussion.

 

The problem is that you are posting on a UK forum, where the commonly available flat-bottom rails are code 75, code 82, code 100. So those are the rails most RMweb members are likely to want to print for. The foot widths differ, so your STL files are likely to need adjustment to suit. You have said that the clips overlap the rail foot only marginally.

 

p.s. on a Forum threads go wherever the contributors take them. To start a topic on which you have control of the content, use the Blogs section. That's what it's there for.

 

cheers,

 

Martin.

 

Martin,

 

You are missing the point (no pun intended) entirely. The topic was intended to be about what might be possible with 3D filament printing with FB rail be it sourced in the US, the UK  or anywhere else. Perhaps I should have made that clearer but I didn't anticipate being descended on by a bunch of nit-picking lawyers. (We have more than enough of them here.)

 

Andy