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TEMPLOT 3D PLUG TRACK - To get up to speed with this experimental project click here.   To watch an introductory video click here.   See the User Guide at Bexhill West.

  • The Plug Track functions are experimental and still being developed. Some of the earlier pages of this topic are now out-of-date.

    For an updated overview of this project see this topic.   For some practical modelling aspects of using Plug Track see Building 3D Track.

    The assumption is that you have your own machines on which to experiment, or helpful friends with machines. Please do not send Templot files to commercial laser cutting or 3D printing firms while this project is still experimental, because the results are unpredictable and possibly wasteful.

    Some pages of this and other topics include contributions from members who are creating and posting their own CAD designs for 3D printing and laser-cutting. Do not confuse them with Templot's own exported CAD files. All files derived from Templot are © Martin Wynne.
  • The Plug Track functions are experimental and still being developed.

    For an updated overview of this project see this topic.   For some practical modelling aspects of using Plug Track see Building 3D Track.

    The assumption is that you have your own machines on which to experiment, or helpful friends with machines. Please do not send Templot files to commercial laser cutting or 3D printing firms while this project is still experimental, because the results are unpredictable and possibly wasteful.

    Some pages of this and other topics include contributions from members who are creating and posting their own CAD designs for 3D printing and laser-cutting. Do not confuse them with Templot's own exported CAD files. All files derived from Templot are © Martin Wynne.

Experimental Plug Track: 3D-printed, CNC-milled, laser-cut

Quick reply >
@Derek

Hi Derek,

Thanks for your thoughts. Certainly not writing out of turn -- that's what Templot Club is here for. It's everyone's turn! :)

At the moment I'm walking a tightrope between letting folks know what I'm doing (so that I can get some feedback), but not letting anyone run away with the idea that it's all ready to be used now, or likely to be any time soon. At present you can build plain track with REA chairs, but that's all. The rest is still just experimental tinkering about, which might or might not ever see the light of day.

My interest in all this is threefold:

1. to discover just what can be done with the latest home machines, which are bringing industrial tech to home workshops. And also what can't be done -- the Cameo cutter was a big disappointment, and there's a reason the small CNC millers are described as for wood-carving, not metal-working.

2. to see if my 73-year-old brain can get into 3D programming enough to kludge some of it into the ancient and creaking Templot code.

3. to find out if enough folks are interested in the result for me to spend time working it up into a usable function and interface for everyone. At present it's clear that only a minority of Templot users have 3D printers, but when you realise that they can now be obtained for much the same cost as an RTR locomotive, or not much more than a 2D printer, it's obvious that 3D printing will eventually be an everyday part of the hobby. You can see that already on some of the forums.

As to how much Templot can be expected to do by itself, and how much users will have to do themselves, it's too early to say. Until I've made enough progress with the code to see where it falls down, and whether I can fix it in my lifetime, I can't make that split. There are some aspects of track design where only a human eye is good enough, as in the timber shoving for example. I can see something similar being needed for the chairing of check rails -- be ready to add "chair heaving" to the Templot lexicon.

Short that is, of a crack team of AI programmers turning up in my shed. :)

cheers,

Martin.
 
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@Paul Boyd

Here's an 0 Gauge layout entirely 3D-printed, mostly FDM with some resin:

https://85a.uk/templot/club/index.php?threads/guildex-show-online.318/post-3024

Martin.
Hmm…. Definitely some possibilities there although I suspect it was done that way to see if he could, rather than as a real solution. I was a little bemused by the fact that he appeared to start looking into track and wheel standards after making track and wheels! I didn’t watch it all though, so maybe I missed something.

Just wondering - when will Templot be able to do bent timbers? 😂😂 (I’ll get my coat…)

Cheers,
Paul
 
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Another day, another button.

hide_timber_outline.png


Hiding a timber outline differs from omit timber in that the chairs/sockets remain, but the timber itself does not. Omit timber removes the timber entirely, including any chairs/sockets.

This is for the DXF exports of course, so that some other timber can claim the chairs when shoved under them.

I haven't yet decided if or how this will have any effect on the rest of Templot and the timbering total lengths. It will probably have the same effect as omitting the timber.

This dialog is now getting very crowded and needs to be bigger -- you buy a bigger monitor, I fill the screen with buttons. :)

cheers,

Martin.
 
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I mentioned that I wasn't happy with the socket-fitting code and might re-write it. That's now done.

As always when you make improvements, you can't understand why you didn't do it that way in the first place. :)

The sockets have been freed from the template which generates them, and now have a separate existence where they can be captured by any shoved timber which surrounds them.

This means that existing BOX files containing partial templates and shoved timbers in complex formations can now be used unchanged for both 2-D and 3-D timbering exports. There is no need for the clunky joins in timbers which I previously suggested for 3-D files.

That moves the dial significantly back towards FDM printing from CNC milling. I'm glad I have both machines and don't need to choose.

Here you can see I have been doing some timber shoving on a crossover to create some long timbers:

new_sockets2.png


Notice for timbers E2, etc., I have hidden the outline to leave only the chairs. These can then be shoved along the rails over the long timber which has been extended from the other turnout.


new_sockets1.png


A couple of things to notice. I omitted one rail to make a partial template, as a test to make sure it didn't upset the timber as it did before.

You can also get creative -- for that one chair the gang had to move it sideways a bit because the screw holes in the timber had stripped, and needed to be filled and re-drilled. :)

I still have some work to do on the trackpad view to ensure the chairs are always visible over the timber infill.

And the result is (ignoring the still missing special chairs):

new_sockets3.png


Notice the moved chair. Also the missing rail. Those timbers are now happy to have only 3 chairs instead of the usual 4.

I'm quite pleased with this. It needs more testing before I release 232a for trials, but I can now see a clear way forward which was cloudy before. And then back to the special chairs.

cheers,

Martin.
 
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I'm going to delete some of the earlier posts about making joins in shoved timbers for FDM -- before Google indexes them for 100 years. If you need to reference any of it, do it now.

edit: now deleted

That's the thing about experimental stuff -- even the posts about it are experimental. :)

Martin.
 
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Another day, another button:

bgnd_chairs_option.png


Having the chairs showing on all background templates makes such a hit on the screen response for a large track plan that you will want to turn them off except when actually timber shoving, or chair heaving, or creating timbering bricks.

You can turn them on and off by delving into the menus, but I thought an easily accessible switch would be helpful.

cheers,

Martin.
 
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I usually come by once a week to catch up on this thread and every time I do I am amazed at your productivity Martin! Thanks so much for putting in such a tremendous effort. I think this is genuinely the future of the hobby for a large subset of people.

I assume one of the "larger" bed resin printers (such as the planned Elegoo Jupiter) would be just as good or better than an FDM printer here?

https://www.elegoo.com/collections/...k-mono-msla-3d-printer?variant=39777858093104
 
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I assume one of the "larger" bed resin printers (such as the planned Elegoo Jupiter) would be just as good or better than an FDM printer here?
@murphaph

Hi Phil,

Thanks for your kind words.

You are adding another option for the timbering bases -- FDM printed, laser-cut, CNC milled, and now resin printed!

My first thoughts re the Jupiter for track building would be:

At that cost you are entering laser-cutter cost territory, and paying for a build height way beyond anything needed for track. But great for a one-piece water tower in 0 gauge. :)

With such high-resolution it might be possible to print the ballast at the same time?

My one doubt would be about the ductile strength of the resin. The intention for Plug Track is that the chairs are a firm interference press fit in the timbers. That might cause resin-printed timbers to fracture. If not immediately, maybe after a few years UV-exposure embrittlement? Like the chairs they would need a good coat of paint to protect them. Or be made a looser fit for gluing instead. A lot would depend on the choice of resin -- there are (expensive) engineering resins which might be needed.

I need to try printing some timbers on my little Elegoo printer and doing some tests. On a small printer the timbers could be bunched-up for printing, and maybe located in a FDM timbering fret (3D template) for accurate gauging and alignment. There is already an option for that:
index.php


So many options, ifs and buts. At some stage someone has got to write all this up. I'm not looking forward to that. :( I still haven't finished the timbering brick topic, but it all applies equally to a resin-printed brick:

index.php


More: https://85a.uk/templot/club/index.php?threads/extracting-a-timbering-brick-from-a-track-plan.295/

cheers,

Martin.
 
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Thanks for your thoughts Martin. I will keep my powder dry on a large resin printer then and see how things develop. As you quite rightly point out, that's laser cutter territory and a small resin printer + laser cutter might well be a better investment than a large resin printer alone. I was kind of thinking of printing bogie stock in 00 at some stage, hence the "wondering out loud" about the newer, larger resin printers....

I was kind of thinking that resin printers might be better at representing most concrete sleepers with their obviously "uneven" profile, falling in to a valley in the middle. I wonder how well FDM printers can do that? Clearly a laser cutter can not help there as the wood will almost certainly always be flat.
 
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I was kind of thinking that resin printers might be better at representing most concrete sleepers with their obviously "uneven" profile, falling in to a valley in the middle. I wonder how well FDM printers can do that? Clearly a laser cutter can not help there as the wood will almost certainly always be flat.
@murphaph

Hi Phil,

You are jumping a long way ahead. Concrete bearers are mostly used for flat-bottom track, and I haven't got anywhere near thinking about FB baseplates yet -- beyond the idea of omitting the jaws from a BH chair. :)

Concrete sleepers are not unknown for bullhead plain track:

mount_pleasant_tunnel.jpg


But I don't know of any bullhead pointwork on concrete bearers.

There would be no inherent difficulty in programming the concrete shape for 3D printing. For FDM the issue might be in getting a smooth top surface if it isn't flat -- although for the above weathered concrete look it might be ideal.

For the pointwork timbers I am already planning some surface detail, such as the switch sole plates, which are seldom modelled and often quite prominent on the toe timber:

index.php


cheers,

Martin.
 
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Yeah I'm like 5 years down the road in my head already lol. The possibilities really are limitless aren't they. Patience is a virtue as they say and I am patiently following this thread with great interest :)
 
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Unless you know different, I think I've got the timbering mostly done, at least for REA bullhead. There is a new timber throw setting in the timbering data in 232a, intended for creating L1-chaired waybeams. I will write more about that later.

So on we go. P chairs (slide chairs) next:

rea_gwr_p_slide_chairs.jpg


REA on the left and GWR on the right.

Slightly confusing because of the two, the GWR looks more like the REA S1 chair with a single outer chair screw and double ribs.

For the special switch and crossing chairs, the REA swaps from 3-screws to 4-screws throughout. The GWR sticks with 2-screws throughout, which is a bit puzzling -- understandable if they were through bolts as on their plain track, but in pointwork the GWR used screws from above like everyone else. The REA fixing looks far more substantial to resist gauge spread -- always a risk in switches resulting from the deflection angle in the turnout road.

There is an alternative REA design, the PJ chair, which has a separate spacer block in the rail web, in effect a cast-iron key, similar to flat-bottom slide chairs. That requires a more upright jaw and a longer bolt. It also has a hexagon nut on the bolt instead of a square nut, for easier spannering between the chair-screw heads.

The PJ would make a more substantial resin print. On the other hand as far as I know they were introduced only in the 1950s (anyone?), so those modelling the grouping era are going to be called rude names for having the wrong style of slide chair. :)

On balance I'm minded to start with the original REA P chair as above. If it proves too fragile, we still have the option of swapping to PJ.

So I'd better make a start on it, instead of putting it off by rambling on about it here.

cheers,

Martin.
 
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p.s. correction :confused:

Oh no it doesn't. Have a hexagon nut. That's only on flat-bottom, for the wider rail foot.

Here's the REA PJ chair:

rea_pj_slide_chair.jpg


Notice that the spacer block is thinner than a normal key, and there is no fresh air below it.

That's because there is no requirement to drop the rail into the chair before kicking it across under an inner jaw.

Martin.
 
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Another conundrum.

The prototype switch opening is 4.1/4".

For EM and 00-SF that's increased to 5.1/4" recommended minimum (1.75mm, thickness of a 20p coin).

Unfortunately that means a conflict with the chair screw heads:
p_chair_opening_em.png


p_chair_opening_em1.png


Would you rather:

a. snip the tops off the chair screws to clear (they are very small in 4mm scale), or

b. have Templot make the chair longer than scale to suit the chosen gauge, or

c. have yet another tickbox option for that, or

d. something else.

Bear in mind for 00-SF that making the chairs longer than scale will reduce even further the distance between opposite slide chairs than is already caused by the under-scale gauge.

p.s. in the drawing I have rotated the rail to vertical.

cheers,

Martin.
 
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B or C. Blades overhanging the chair screws look worse than the chair being a little too long! (Not that I model in either of the scales you mention 😀)

I think I agree. But you can write the replies when folks share chairs, and EM slide chairs don't fit in P4 sockets! :)

Martin.
 
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If you look at what Len Numan did with the Exactoscale chair range, for 00 & EM gauges (4mm scale E4CH 301A) he made a slightly larger slide chair (for all P positions) and a P4 slide chair (E4CH 302A).

If anything there should be a 3rd version for standard 00 gauge, as the 4mm scale one is fine for EM & 00SF
 
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@Hayfield

Thanks John. I was hoping someone might come up with a clever wheeze to reduce the workload, but I knew it would come down to more tickboxes* in the end:

dxf_switch_opening.png


Set automatically from the current gauge/scale, but can be changed before exporting the file.

This dialog is getting out of hand. It will need a full re-design before a full release for Plug Track. :(

*I suspect we shall have to leave behind any hope of compatibility with Windows95, 98, ME. "Out of resources" errors.

cheers,

Martin.
 
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Now that I'm looking at the switch and crossing chairs, I have had to make a decision about something I've been pondering for ages. Should the chairing be prototypical or programmatic? I've settled on programmatic.

What do I mean by that? Suppose you have created an irregular diamond-crossing which fits your track plan nicely, and one of the V-crossings is showing as 1:7.38 angle. Now obviously no such size of V-crossing exists on the prototype -- the nearest size, 1:7.5, would be used instead. And the big 'ammer would be brought into play to make it fit -- a few days running-in under traffic soon removes any rough spots. That is also what you do if building with C&L or Exactoscale chairs, because they don't make 1:7.38 crossing chairs either, although I doubt model running-in has much effect.

To be strictly prototypical therefore, Templot should do the same, and I should implement a corresponding big 'ammer function.

Well I'm not going to -- it's just too much of a minefield of conflicting dimensions and prototype variations. I am hoping to finish this project within my lifetime!

Instead, Templot will programmatically create 1:7.38 crossing chairs for a perfect fit. Only you and I will ever know the difference, no-one else will notice. If that's not something you can live with, -- using Templot isn't compulsory. :)

Another example of programmatic chairing will be for the switch block chairs. Suppose you shove one of the switch timbers along a bit, like this:

shoved_block_chair.png


You know and I know that you should never do that. The block chairs support angled rails, and will fit the rails in one position only. You can't shove switch timbers more than an inch or so under the chairs, and the chairs need to stay put while you do it.

But Templot doesn't know that, and will happily shorten or lengthen the block chair, and adjust the rail angle, as you shove the timber along. Whereas the prototype has only a few fixed sizes of block chair, not an infinite range of sizes.

But in a cramped model design, you may need to shove switch timbers more than a bit, so this unprototypical result might be useful.

Again, I'm creating these chairs programmatically in order to have some hope of chairing the whole range of switches in my lifetime.

But this decision does have consequences. It means the 3D chairs file and timbering brick file will be a matched pair and need to be created at the same time and kept together, and not interchanged with the files for other templates or bricks, even if the templates are nominally the same size.

I'm intending that it will be possible to bunch together all the chairs from a brick for resin-printing, and print a paper chart showing which chair goes where on the templates.

cheers,

Martin.
 
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Martin

Certainly from a track builders point of view this is the correct way, I have found though when using the Exactoscale parts which are designed for P4 timber spacing, they also work well for both EM and 00 spacing, however in the case of separate chairs the next few standard chairs have their position altered (if only for a few thou), but are we talking about amounts that within normal build tolerance ?

Or am I misunderstanding what you are saying

Another thought does the gauge alter the slide rail lengths, if so would you have to increase them up to PL2 position ?
 
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message ref: 3124
.
Now that I'm looking at the switch and crossing chairs, I have had to make a decision about something I've been pondering for ages. Should the chairing be prototypical or programmatic? I've settled on programmatic.

What do I mean by that? Suppose you have created an irregular diamond-crossing which fits your track plan nicely, and one of the V-crossings is showing as 1:7.38 angle. Now obviously no such size of V-crossing exists on the prototype -- the nearest size, 1:7.5, would be used instead. And the big 'ammer would be brought into play to make it fit. That is also what you do if building with C&L or Exactoscale chairs, because they don't make 1:7.38 crossing chairs either.

To be strictly prototypical therefore, Templot should do the same, and I should implement a corresponding big 'ammer function.

Well I'm not going to -- it's just too much of a minefield of conflicting dimensions and prototype variations. I am hoping to finish this project within my lifetime!

Instead, Templot will programmatically create 1:7.38 crossing chairs for a perfect fit. Only you and I will ever know the difference, no-one else will notice. If that's not something you can live with, -- using Templot isn't compulsory. :)

Another example of programmatic chairing will be for the switch block chairs. Suppose you shove one of the switch timbers along a bit, like this:

View attachment 2675

You know and I know that you should never do that. The block chairs support angled rails, and will fit the rails in one position only. You can't shove switch timbers more than an inch or so under the chairs, and the chairs need to stay put while you do it.

But Templot doesn't know that, and will happily shorten or lengthen the block chair, and adjust the rail angle, as you shove the timber along. Whereas the prototype has only a few fixed sizes of block chair, not an infinite range of sizes.

But in a cramped model design, you may need to shove switch timbers more than a bit, so this unprototypical result might be useful.

Again, I'm creating these chairs programmatically in order to have some hope of chairing the whole range of switches in my lifetime.

But this decision does have consequences. It means the 3D chairs file and timbering brick file will be a matched pair and need to be created at the same time and kept together, and not interchanged with the files for other templates or bricks, even if the templates are nominally the same size.

I'm intending that it will be possible to bunch together all the chairs from a brick for resin-printing, and print a paper chart showing which chair goes where on the templates.

cheers,

Martin.
Hi Martin

That all sounds an eminently sensible and pragmatic solution to me!

Cheers,
Paul
 
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but are we talking about amounts that within normal build tolerance ?

Or am I misunderstanding what you are saying
@Hayfield

Hi John,

Providing you use the chairs from the corresponding STL file, and not some you had left over from a previous file, they should fit the corresponding timbering base perfectly, and there should be no need to rely on build tolerances to make things fit.

I say "should" because I haven't actually written the code yet. :)

Also, it is necessary to set the shrinkage rates correctly. At present there is a single allowance on the dialog which is used for all 3-D files, and ignored for all 2-D files. The default I have on there at present is 1.5% which is about right I think for the resin-printing, but maybe a bit too much for FDM filament printing. Indeed with the wide footprint of a typical timbering brick on the build plate, there may be very little shrinkage of the timbering brick at all, unlike when printing more bulky items having a smaller footprint. My test prints tend to confirm this. But like most plastics, some age-shrinkage may take place afterwards over time.

In addition, all machines 2-D and 3-D may need scaling adjustments to cover for any mechanical errors in the pitch of lead screws, pitch of toothed belts, diameter of pulleys, rollers, etc., on individual machines.

All this is still very much in the air and subject to trial and error when we are in a position to start making Plug Track in anger.

Another thought does the gauge alter the slide rail lengths, if so would you have to increase them up to PL2 position ?

The P slide chairs are all a single size along the rail, like the S1 and L1 chairs, but will be adjusted in length to suit the current scale/gauge setting -- see my previous reply. They should therefore be interchangeable in different templates, provided you don't mix up the P4 ones with the EM ones, etc. Beyond the P chairs are the block chairs. These will be programmatically generated to match the switch, as I mentioned, so they won't necessarily be interchangeable with any other template and will need to be kept for the corresponding timbering base if you want a perfect fit.

At some stage all this stuff will need to be written up, with all the ifs and buts, and I'm not looking forward to it. But that's jumping a long way ahead, because I'm still at the more fundamental stage of making stuff work.

cheers,

Martin.
 
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@Hayfield

p.s. John, apologies if my previous post appeared in bits, I think I've found a bug in this forum editor related to the Tab key.

I have posted a bug report on the XenForo site.

cheers,

Martin.
 
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Hello Martin,
With regard to the switch blade over hanging chair bolts.
Could one not simply file a couple of slight hollows in the bottom of the switch blade to clear the bolt heads?
Trevor.:)
 
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Hats off to Martin.
By providing four more radio buttons, Martin is allowing you (the builder) to choose which solution best suits you.
Having used the 301A Exactoscale slide chairs for OO-SF turnouts I don't think you really notice that they are longer once laid.
ps time to get my eyes tested again then!
pps must save a 20p piece before they go out of circulation in this cashless society!
 
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I'm intending that it will be possible to bunch together all the chairs from a brick for resin-printing, and print a paper chart showing which chair goes where on the templates.
In the far off future, please can we have a template timber bunch facility for the 2D export for use when Laser Cutting but in this case with the timbers adjacent. ie sharing a cutting line. This makes the laser cutting more economical when outsourcing.
Obviously when 3D printing the timbers need to be discrete and the bunching is just to maximise the use of the print bed area.
Steve
ps but don't let this request distract from chair production ;)
 
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In the far off future, please can we have a template timber bunch facility for the 2D export for use when Laser Cutting but in this case with the timbers adjacent. ie sharing a cutting line. This makes the laser cutting more economical when outsourcing.
Obviously when 3D printing the timbers need to be discrete and the bunching is just to maximise the use of the print bed area.
@Steve_Cornford

Hi Steve,

The timber separation will be adjustable to whatever you set. If you want them to share a common cutter line it will be up to you to set the separation accordingly, allowing for the laser kerf width.

If the timber kerf lines end up coincident I will find some way to omit one of them, so that the cutter lines are not duplicated in the DXF file.

If you don't have any waste between the timbers, how do you hold it all together while cutting?

cheers,

Martin.
 
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If you don't have any waste between the timbers, how do you hold it all together while cutting?
Don't know.
They cut the sockets first, then the timbers.
LaserCutSleepers.jpg

This is what I got back. There is what appears to be masking tape on the back.
I can only assume that it is gravity.
They do offer a "taping" service as an option, but this is to alleviate the burn marks on the surface.
I did not opt for the "taping" service, as I was not too worried about burn marks, as sleepers(or timbers) will be stained with indian ink etc
Most of the sockets that are missing have fallen out with my handling.
Just like punched cards chad from my early programming days.
Miniature bricks anyone?
The cost depended in part upon the total length of lines cut, hence request for "bunch".
The sample I sent you of the turnouts etc was just as output by Templot, the above was as a result of the cutting service editing one of the files I had output from Templot.
I will ask the cutting service about duplicate lines. They might have some utility that removes them.
Steve
 
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Probably a question for Martin, but do you think your CNC mill would work with 2mm thick Walnut or Mahogany? i.e. work as in "work as you're intending to work with MDF". I can send you some once my order from Cornwall Model Boat arrives if that helps.

Thanks

Richard.
 
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@richard_t

Hi Richard,

I'm fairly confident the machine is capable -- it is advertised as suitable for engraving hardwoods, and for this plug track application holding a precise cut depth is not necessary. What I'm not so sure about is the amount of splitting and raised burrs which might occur with natural woodgrain. The same applies to plywood of course. So far I have experimented only with MDF. I intend to get some "downcut" end mills for further experiments with natural wood. Both solid wood, and applied as thin iron-on hot-melt veneer on an MDF base.

My planning so far has been for 3mm material -- the current default settings for the plugs require a socket 2.5mm deep. For 2mm material the plugs will need to be reduced (unless you laminate it with an MDF sub-base). My experiments so far for the "plug-in" method have found it necessary to have a good location depth on the plugs so that the chairs can be reliably located loosely in the sockets before pressing the rail home. Otherwise assembly gets too fiddly. For the "slide-in" method with the chairs fixed in place first one at a time, the plugs can be less deep.

The "slide-in" method is more applicable than it first seemed when you realise that not all the other chairs need to be in place on the timbering base before sliding a piece of rail into position, only the actual chairs being slid into are needed. Adding subsequent chairs to the base may then trap the rail so that it couldn't be slid out again. This differs from the situation where all the chairs are integral with a timbering base from the start (as in turnout kits). As I've mentioned a few times there is still a lot of learning and trial and error to work through before this project is done.

I'm happy to receive some offcuts of your wood if you have some to spare. It doesn't need much to make a few trial cuts. What panel size have you managed to obtain in 2mm thickness? Are you planning to build panels by gluing stripwood side-by-side?

cheers,

Martin.
 
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Hi

Cornwall Model Boats sell sheet in 1m by 100mm, which I've ordered a few of Walnut and Mahogany, along with some 2mm x 4mm of each strip. My original plan was to cut down the 1m x 100mmm into 3.3mm strips for "normal" sleepers using my Proxxon table saw (the cheaper of the 2 available - the fence is rubbish, so might be something I "upgrade" using the 3D printer).

Happy to send you some - 1 of each letter size? (240mm x 165mm, perhaps a little bit smaller).

Richard.
 
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More buttons.

Testing the MINIBO printer has shown up a significant difference in the PLA shrinkage compared with BIBO. In fact on the MINIBO there doesn't seem to be any shrinkage at all, and it actually needs a slight negative adjustment to get accurate results. This must be due to the cold work plate instead of the heated glass bed on the BIBO. It's difficult to separate shrinkage variations from errors in the machine resolution, but now that I know how much difference the backlash correction makes, I shall be re-testing the settings for the BIBO.

Whatever, it means using different adjustment/shrinkage settings for FDM and resin printing, and to avoid having to change the settings between exports that means yet more buttons:

dxf_3d_options.png


The CAD option means zero adjustment, any changes wanted being made in the CAD program.

If the export is intended for 3D printing it will be important to click the right option before exporting the file (and to have set the right amount of adjustment for your printer).

More about the MINIBO:

https://85a.uk/templot/club/index.php?threads/another-fdm-printer.340/

cheers,

Martin.
 
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Hi

Cornwall Model Boats sell sheet in 1m by 100mm, which I've ordered a few of Walnut and Mahogany, along with some 2mm x 4mm of each strip. My original plan was to cut down the 1m x 100mmm into 3.3mm strips for "normal" sleepers using my Proxxon table saw (the cheaper of the 2 available - the fence is rubbish, so might be something I "upgrade" using the 3D printer).

Happy to send you some - 1 of each letter size? (240mm x 165mm, perhaps a little bit smaller).

Richard.
Eventually my order from Cornwall Model Boats turned up this morning - the walnut and mahogany strips and sheet have survived but I also ordered some MDF sheets as well, and each one of those are damaged in some way, and also they are now out of stock on some of the MDF and so didn't fulfil my order. I noticed my local timber merchant/DIY* place sells a variety of pre-cut MDF (I suspect for picture framing/backing) so I suspect that might be a better route.

Anyhow, if still you'd like some of the Walnut/Mahogany sheet, I'm sure I can organise that over the next few days (he says... ha ... ha ... ha ...)

All the best

Richard

* Along with offcuts of various bits of plywood, that I can't help getting ... sigh ...
 
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