Rail filing jigs - 3D printed

[Martin Wynne]

I'm pleased to report this idea has worked out well.

Here's the STL for one half of a 1:5 vee rail filing jig for C&L code 75 bullhead. Overall size is 145 x 28 x 10 mm:

And 3D printed:

Each half took about an hour to print, the total cost of material for both works out at 86p. I used square holes to make it easier to adjust the size for a close fit on the M6 roofing bolts, but it came good first time. Add a few 1" penny washers and off we go:

Deburr the rail end, slacken the bolts, slide in the rail, tighten the bolts, a few strokes with a nice sharp 2nd-cut file,and:

After filing half a dozen rail ends there is no measurable wear. I think this jig would be good for a whole layout, but if not, just print yourself a new one while having some lunch.

The polymer is eSUN PLA-PLUS toughened PLA:

https://www.amazon.co.uk/gp/product/B07FQ75QG2

It's very tough, but I assume other makes are the same (video):

https://d12xgfa7l6zj5h.cloudfront.n...-202e0281b648/default.jobtemplate.mp4.480.mp4

STL files attached if anyone wants to print one.

I sliced it in Simplify3D which seems better at engineering components than Cura (which is better for detailed models): 0.15mm layers, 4 solid layers top and bottom, 25% infill. I used 210degC for the first layer, and 195degC for the rest. Nozzle dia. 0.6mm. 2 shell walls. If using a 0.4mm nozzle maybe 3 shells.

I now have several ideas for other bending and filing jigs.

cheers,

Martin.

 

[Charles Orr]

I shall have a go at printing those Martin.
Thank you for the STL files.
I'll let you know how I get on.

Cheers
Charles

 

[AndyB]

Snap!

Nice work with the jig BTW. I can confirm that that stuff is a tough as nails.

Reminds me of a story about my biggest brother when he went to get a haircut. The barber complained to him that

"Yer hair's like peen wire. The scissors jist boonce aff!"

 

[Martin Wynne]

@AndyB

A bench vice is always the most unloved of tools. But yours looks to be in a better state than mine. How did you keep the tommy bar so shiny?

There was a time when everything had "MADE IN ENGLAND" cast very firmly into it. Nowadays it's rare to see, but step forward Peco.

The jig worked out really well. Which was encouraging after the disappointment of the Cameo.

It leads to lots of ideas -- click on a template and get a STL file for a vee filing jig, for any angle. And a switch filing jig. And a knuckle bending jig, and a stock rail set bending jig, and...

But first to get 228a out and some more chairs done for 3D Plug Track.

cheers,

Martin.

 

[Martin Wynne]

I have added a refinement to the filing jig design:

A notch in the corner indicates the jig angle, in mm. So if the notch measures 5mm long, this is a 1:5 RAM jig.

This is much easier to code than engraving numbers into the surface in the STL file. Most folks would write the size in felt-tip pen on the jig, but if it gets rubbed off, this notch is a permanent physical size indication.

p.s. this is not in the STL files which I posted earlier. They are 1:5 RAM, so remember to write that on them.

cheers,

Martin.

 

[Hayfield]

I have added a refinement to the filing jig design:

View attachment 1665
A notch in the corner indicates the jig angle, in mm. So if the notch measures 5mm long, this is a 1:5 RAM jig.

This is much easier to code than engraving numbers into the surface in the STL file. Most folks would write the size in felt-tip pen on the jig, but if it gets rubbed off, this notch is a permanent physical size indication.

p.s. this is not in the STL files which I posted earlier. They are 1:5 RAM, so remember to write that on them.

cheers,

Martin.

Martin

Just the job, on the other side you could fit a 9' switch ?

John

 

[Hayfield]

Email sent

John

 

[Martin Wynne]

I have added yet another tickbox to the DXF dialog:

Ticking this box will ignore everything else and create the file for a 1:5 filing jig, as above. So don't click it accidentally.

In 228a that's all it will do, no adjustments or other sizes. That will have to wait for 228b.

p.s. to get as far as the DXF dialog, you must have some background templates, even though they will be ignored.


To get the file for the other half of the jig, change this to -1.0 :

DO NOT set it to anything other than 1.0 or -1.0, otherwise all bets are off.

Change it back to 1.0 afterwards.

DO NOT make any change to it for the 3-D track.

cheers,

Martin.

 

[roythebus]

Any chance of doing a V and K crossing assembly jig, something that will hold the rails in the right place while they're soldered together? That way you're guaranteed a perfect crossing every time.

 

[Martin Wynne]

Any chance of doing a V and K crossing assembly jig, something that will hold the rails in the right place while they're soldered together? That way you're guaranteed a perfect crossing every time.

@roythebus

Hi Roy,

The polymer melts at soldering temperatures. So I don't think soldering jigs are possible using filament printing. Resin-printing might be different, I don't know enough about the various resins.

However I'm not convinced that soldering is essential for vees. Or that vees need to be created as a single unit.

If, big if, the vee rails are accurately prepared*, and if, big if, they are accurately held in the chairs, it should be possible to assemble the vee rails separately into the crossing chairs along with the wing rails to create a full V-crossing. Then a little penetrating cyano from below should set the whole thing solid. Or maybe with a smear of epoxy too.

I'm including a lot of adjustments into the chair settings for the Plug Track to achieve a perfect fit on the model rail sections, and we might also print some spacer blocks. If, big if, it all works it would be a game changer. Watch this space.

* this is the key, hence the filing jigs 3D-printed to match the template.

cheers,

Martin.

 

[Hayfield]

Martin

I have tried out the jig you sent, and it seems to work perfectly with bullhead rail

Slide the rail in and finger tighten the bolts

I was amazed that as you said the files slides over the Jig the rail files to a nice accurate angle

Easily soldered together (I used the EMGS jig to hold the work, a thick card template would also work)

Job done, what a result

I think it could be possible to use flatbottom rail with a bit of adjustment

Also an easy switch blade filing jig can also be produced by having a shallower angle

Well done and so quickly amazing !!!!

 

[Martin Wynne]

@Hayfield

Hi John,

Wow -- all that before lunch! Royal Mail must be doing well in your parts, my mail hasn't arrived yet.

I'm glad it worked ok for you. Thanks for the quick detailed feedback.

For flat-bottom rail the slot in one half needs to be wider (for the foot) than the other (for the head). That makes the jig handed, so you would need two slots on the jig, one for each hand. It's all doable, I just need 48 hours in a day to progress it.

cheers,

Martin.

 

[richard_t]

Hi all

I have a significant birthday this year (a x0 type thing), and given everything going on, I don't think I'll be going away on it for a treat, and being a recent-ish widower I don't really fancy it on my own anyhow - even though I've always fancied staying and eating at Le Manoir aux Quat'Saisons.

So....

I'm planning on treating myself to a 4K resin 3D printer.

My question is - is there a resin that would be tough enough to produce these jigs. I won't be getting it until later in the year, they way the garden (read weeds) are growing this year, it would just sit in it's box until the colder weather anyhow.

Thanks

 

[Martin Wynne]

@richard_t

Hi Richard,

Have a look at:

https://www.hubs.com/knowledge-base/sla-3d-printing-materials-compared/

Scroll down to engineering SLA resins.

I think the one you would want is the Durable (PP-like) resin.

I'm using the Tough (ABS-like) resin for the chairs. It definitely isn't suitable for filing jigs and files easily.

There is a downloadable guide to engineering 3D printing on that page (if you jump through a few hoops).

cheers,

Martin.

 

[Steve_Cornford]

How about a 3D printed combined Set and Knuckle Bend Jig?

 

[Martin Wynne]

How about a 3D printed combined Set and Knuckle Bend Jig?

Hi Steve,

Already planned. Clicking on a template gets the 3D file for all the filing and bending tools needed to build it, at the required angles. I'm hoping that if the rails can be prepared with sufficient accuracy, no soldering will be needed. Just assemble in the chairs and apply a little penetrating low-viscosity cyano to hold it solid.

It will probably require filament printing rather than resin for the tools.

cheers,

Martin.

 

[KHC1]

Just finished printing one looks good to me. I have a simple rail bending jig in design at the moment. Just thinking about a blade filing jig.

Keith

 

[Hayfield]

Just finished printing one looks good to me. I have a simple rail bending jig in design at the moment. Just thinking about a blade filing jig.

Keith

Keith just do the same as the Vee jig

This is one designed for flatbottom rail, so is double sided, at one end you thread the vee the other the switch. Works equally well with bullhead and only needs to be one sided. Quite nifty bit of kit as it works between code 75 and 100. This one is a 1-6

The EMGS do a simple cheap etched common crossing assembly jig

https://emgs.org/product/brass-fret-for-constructing-common-crossing-jig/https://emgs.org/wp-content/uploads/2021/03/1_2_1_4_pages_all.pdf

 

[KHC1]

Just a thought for Martin. I have printed out the filing jig and put together. May it be possible in future jigs if on one side there could be say two locating pegs with corresponding location holes on the other side.

Keith

 

[KHC1]

Quick pic of my filing jig printed out. Many thanks Martin.

Keith