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

[Steve_Cornford]

Hi Richard,
believe I am right in saying that when a particular template is output, whether to paper printer, DXF file, or .STL file the gauge is output as defined for that template, so I assmume if you have gauge widened a particulr EM template (18.2mm nominal) to say 18.3 mm, then that is what gets printed. If outputting sockets they will be positioned (for that template) so that when the chairs are plugged in, the gauge will be 18.3mm. It is all driven by Templot, which you are in control of.
Steve

 

[Steve_Cornford]

Two parts of a clip, before trimming the web on the end of the sleepers to allow mating to take place.

Both the jaw and the Tommy bar just overlap the flange rather than overlap an actual sleeper. I did this so that with the standard size clip the two sleepers end up at the correct distance apart. Seems strong enough as integrity only needed until sleeper base glued down.


Now for a squirt of primer etc, then stick down and have a go at ballasting and plugging, or should that be plugging then ballasting?

 

[richard_t]

Hi Steve

That might work for simple curves but not for transitioned curves where I'm sure the amount of gauge widening would also transition.

Richard

 

[Martin Wynne]

@Steve_Cornford

Hi Steve,

There is a recess around the underside of the clip to allow for elephant's foot. For the amount of EF you are getting, you need to increase the bottom offset setting:

To get the clip where you want it without disturbing the sleeper positions, instead of make split at peg, click do > blank up to peg menu item.

Sorry, in my previous post I simply posted enough to let you test the printing of the clips. If you want to use the results for an actual model, there is rather more to it. Generally the brick templates are intended to be derived separately from the track plan templates, rather than replace them. For the full chapter and verse you need to read this topic from the start:

https://85a.uk/templot/club/index.php?threads/extracting-a-3d-timbering-brick-from-a-track-plan.295/

and then ignore all the experimental bits which I have since changed.

One day I will get all this stuff written up properly, but if I stop to do that now I never will get any more chairs done.

cheers,

Martin.

 

[Martin Wynne]

@richard_t @Phil O

Hi Richard, Phil,

I'm aware of the need for gauge-widening, and transitioning into and out of gauge-widened sections, and the widened check-rail gaps resulting therefrom.

I have several ideas for how best to achieve it. But unfortunately I can't do everything at once. I said at the the start of this Plug Track project that it will be a long, long, road -- but I don't think anyone believed me.

It will be a major achievement just to get to a complete single straight turnout -- I haven't even got that far yet.

As Phil says, for a constant gauge-widening on plain track, you can use gauge > modify current settings > modify track gauge... and it will work fine for Plug Track. But don't do that for pointwork templates, because it will change the geometry.

cheers,

Martin.

 

[Martin Wynne]

.
Sorry, more brain-fade. Mixed up Steve and Phil. Apologies.

 

[Steve_Cornford]

Hi Martin,
Thanks for the tip, its good to try out & learn something new each day.
This is not for an actual model, it is just so I can try out ballasting that covers 3D printed timber flanges & clips etc, and compare that with using laser cut ply timbers glued to a cork sub-base (emulated with 3mm ply at present) using locator plugs etc.
To help guide decision making regarding purchase of an FDM 3D printer for the bases, or stick with out-sourcing laser cut ply timbers.
I know this is all experimental but it is great fun trying this out, as long a sit doesn't try your patience.
I can see that there is a bit if faff gluing the timbers down individually with locators, then removing locators before plugging in the rail mounted chairs, but this might be balanced by the time taken to produce all the 3D printed bricks.
I can see that resin printed bases are not ideal, as they are not really a "bash" fit in the way that your FDM printed timber bases are designed to accomodate a "bash" fit,

The latest resin timber bases I printed were still at the default shrinkage allowance of 0.15% and measuring them (along the rail) I suspect that in the x direction 0.05% or even 0.00% would be better.
Having plugged some chairs in the gauge seems to be more like 16.3 than 16.2 so the y direction also needs reducing (for use on my printer), and this perhaps re-inforces the need to reduce shrinkage % as you have previously noted.

Just got to find my bags of ballast.

Steve
ps before actual modelling begins I will have to stop dithering between OO-SF, EM and P4

 

[Martin Wynne]

Would it be worth proceeding with the check rail chairs as a further test of proof of concept?
I am assuming that these would have fixed jaws on the stock and the outer jaw of the check rail with a loose jaw on the inner jaw (the one nearest the middle of the track?

@Steve_Cornford @ralphrobertson

Hi Steve, Ralph,

We now have 3 of us who have succeeded in printing the loose jaws, to the intended size, and inserting them on some rail.

So I'm going to proceed on that basis for the check rails at least. That means the check rail chair bases will be in one-piece, slide-on for the stock rail, and a loose jaw at the inner end against the check rail.

For anyone not happy with the loose jaw, unticking the relevant option will cause the chair to be printed as one piece with a solid inner jaw for slide-on both rails. That will mean either a) bash-fit both stock rail and check rail at the same time, or b) fit the check rail afterwards by sliding it through the chairs, the flare angles being "persuaded" through the chair jaws. In some complex formations there won't be room between other rails to slide it into place, and a) would be the only option.

But using the loose jaws makes it easier -- IF you can see them. The check rail can be prepared to match the paper template, tried in position until it is just right, and then finally fixed by inserting the loose jaws. If it is still not quite right, the loose jaws can be pulled out* and the rail modified or replaced as required. If the rail is a bit loose, the jaws can be pulled out and replaced with ones having a slightly thicker key. And because the check rail does not need to slide though the chairs, there is no need to file a lead-in chamfer on the rail end -- the ends can be dead square and flat as the prototype by touching them against a sanding disc.

The same ease of assembly with loose jaws would apply to the wing rails and knuckle bend at the crossing -- no need to get it dead right first time. IF you can see them.

*pulling out the loose jaws without damaging them is quite tricky -- they are locked under the rail head. It's best to regard them as disposable, and use a fresh one. You can print about 1000 for 10p, so that's not likely to be a hardship. To remove them I have found the easiest way is to grip them gently with the tip of the Xuron cutters, and pull them away from the rail. If you accidentally cut through one in the process, the remains can be pushed out from below.

cheers,

Martin.

 

[ralphrobertson]

@Steve_Cornford @ralphrobertson

Hi Steve, Ralph,

We now have 3 of us who have succeeded in printing the loose jaws, to the intended size, and inserting them on some rail.

So I'm going to proceed on that basis for the check rails at least. That means the check rail chair bases will be in one-piece, slide-on for the stock rail, and a loose jaw at the inner end against the check rail.

For anyone not happy with the loose jaw, unticking the relevant option will cause the chair to be printed as one piece with a solid inner jaw for slide-on both rails. That will mean either a) bash-fit both stock rail and check rail at the same time, or b) fit the check rail afterwards by sliding it through the chairs, the flare angles being "persuaded" through the chair jaws.

But using the loose jaws makes it easier -- IF you can see them. The check rail can be prepared to match the paper template, tried in position until it is just right, and then finally fixed by inserting the loose jaws. If it is still not quite right, the loose jaws can be pulled out and the rail modified or replaced as required. If the rail is a bit loose, the jaws can be pulled out and replaced with ones having a slightly thicker key. And because the check rail does not need to slide though the chairs, there is no need to file a lead-in chamfer on the rail end -- the ends can be dead square and flat as the prototype by touching them against a sanding disc.

The same ease of assembly with loose jaws would apply to the wing rails and knuckle bend at the crossing -- no need to get it dead right first time. IF you can see them.

cheers,

Martin.

My previous post about the separate jaws and keys was made before I tried to use them and despite several being separated in my hand washing process I have to say that with the aid of an Optivisor and my regular fine tweezers which I always use I found the process actually quite easy. Would I want to make a complete turnout that way - probably not, but for a few chairs it would not be a problem and my eyes really are getting bad these days. I never seem to be able to wear the right specs for the job, always swapping them over!

Ralph

 

[Steve_Cornford]

Hi Ralph,
When you say complete turnout that way, if I take a C10 turnout for example, I calculate there will be 102 fixed jaw chairs, and 32 loose jaw chairs needing 40 loose jaws between them, so perhaps not so onerous. (based on Scalefour Society commissioned LNER C10 turnout template).
It is good to know that you are actually using a combination of lasercut card sleepers and S1 plug chairs on a real working layout.
Steve

 

[ralphrobertson]

It's a good thing I am modelling an industrial location with B6 and A5 turnouts! Working on the wiring at the moment and once its all running will post something showing Templot generated track using card sleepers and resin 3D chairs.

Ralph

 

[Phil O]

My previous post about the separate jaws and keys was made before I tried to use them and despite several being separated in my hand washing process I have to say that with the aid of an Optivisor and my regular fine tweezers which I always use I found the process actually quite easy. Would I want to make a complete turnout that way - probably not, but for a few chairs it would not be a problem and my eyes really are getting bad these days. I never seem to be able to wear the right specs for the job, always swapping them over!

Ralph

Hi Ralph,

I'm like you, my normal glasses are verifocals, but for close modelling work, I have a pair of x3 reading glasses, which has made one helluva difference, but I need to swap between them quite frequently, sometimes and on some occasions I even resort to the x3 glasses, plus an optovisor. The joys of getting old, I think not! The glasses were courtesy of a BOGOF deal.

 

[Martin Wynne]

To help guide decision making regarding purchase of an FDM 3D printer for the bases, or stick with out-sourcing laser cut ply timbers.
I know this is all experimental but it is great fun trying this out, as long as it doesn't try your patience.
I can see that there is a bit if faff gluing the timbers down individually with locators, then removing locators before plugging in the rail mounted chairs

@Steve_Cornford

Hi Steve,

Not trying my patience at all, I value the feedback greatly. It's encouraging me to get on and make some progress with this project.

I'm glad you are finding it fun -- me too. That is the purpose of a hobby.

I have now ordered yet another FDM printer -- this one:

https://www.amazon.co.uk/gp/product/B09BN55WQR

which is currently available at a good price. It should be here tomorrow. It requires much more assembly work than the later Neptune 3 version, but that costs over 40% more for much the same printer. Also I prefer the manual levelling on the older version for printing something dead flat and the same thickness all over -- such as a timbering brick. The new "auto levelling" function doesn't physically adjust the build plate, it simply compensates the thickness of the first layer to allow for an unlevel build plate.

I don't actually need a third FDM printer, the BIBO is still working fine. But it's now 5 years old and seemingly no longer available. So it's not likely anyone else making plug track is using one. I want to be able to test the plug track and set the defaults based on the type of printer most users are likely to have. I know one or two are thinking of getting into 3D printing purely on the strength of plug track, so I want to be able to make a video saying "get one of these, click this, do that" and so on. At present I can do that for the chairs, but not for the timbering bricks.

but this might be balanced by the time taken to produce all the 3D printed bricks.

The big difference there is that an FDM printer runs unattended. Yes it can take hours rather than minutes, but you just set it running and walk away. With no afterwork needed. It prints tomorrow's timbering base (ready to use) while you are building the one it printed yesterday.

cheers,

Martin.

 

[Steve_Cornford]

Hi Martin,
Ah yes I was going to ask you about the Neptune 2S, as it seems to have the same x-y build plate size as the Neptune 3, just a smaller z size, but we do not need a great height for timber bases.

I have ordered a set of your tweezers and the reading glasses!

I think you will have more fun tomorrow assembling your Neptune!

Steve

 

[Martin Wynne]

Hi Martin,
Ah yes I was going to ask you about the Neptune 2S, as it seems to have the same x-y build plate size as the Neptune 3, just a smaller z size, but we do not need a great height for timber bases.

I have ordered a set of your tweezers and the reading glasses!

@Steve_Cornford

Hi Steve,

I've never used the BIBO at anywhere near the full Z capacity, and I doubt I will ever do that with the Neptune. I can't think of anything 10 inches tall that I might want to print for modelling.

One issue at the back of my mind which I want to resolve (and the real reason for getting the Neptune) is the X-Y resolution for this style of open-frame FDM printer -- there are a lot of them about. The BIBO claims 0.05mm, and so does even the little MINIBO. The Neptune says nothing about resolution (travel per motor step) but claims +/-0.1mm accuracy for the finished print. That's not very impressive.

On both the BIBO (and the MINIBO with Templot's backlash correction function) I've achieved very good accuracy by careful measurement and adjustment of the shrinkage settings, better than +/-0.1mm. It's important for the socket sizing of course.

I shall be very disappointed if I can't achieve the same on the Neptune by tweaking the settings. As usual it's proved impossible to get this sort of information from any website or by asking anyone, the only way to find out is to get one and see.

I think you will have more fun tomorrow assembling your Neptune!

I hope it can be called fun. As usual with these things, the quoted assembly time is how long you will need to lie in a darkened room afterwards. The actual assembly time is always a fortnight.

I'm currently working on the loose jaw pin holder for the tweezers.

cheers,

Martin.

 

[Steve_Cornford]

Hi Martin,
Will (the holder) be FDM or Resin printed?
Steve

 

[Martin Wynne]

Hi Martin,
Will (the holder) be FDM or Resin printed?
Steve

Hi Steve,

I'm intending to print it on the Mars (resin). Hopefully it will be strong enough. If not FDM. I will post the file here.

I might also try a brass version on the CNC if I can still see to make a 0.6mm D-bit on the cutter grinder.

cheers,

Martin.

 

[Martin Wynne]

Hi Ralph,
When you say complete turnout that way, if I take a C10 turnout for example, I calculate there will be 102 fixed jaw chairs, and 32 loose jaw chairs needing 40 loose jaws between them, so perhaps not so onerous. (based on Scalefour Society commissioned LNER C10 turnout template).
It is good to know that you are actually using a combination of lasercut card sleepers and S1 plug chairs on a real working layout.
Steve

@Steve_Cornford @ralphrobertson

Hi Steve, Ralph,

IF, big IF, you were prepared to do the whole thing loose-jawed, another option comes into play. If the timbering base is resin printed, the slotted chairs could be printed integral with the timbering base instead of separate bash-fit chairs. Saving a lot of time and improving the final accuracy (e.g. for P4).

So instead of getting a separate FDM printer and a small resin printer, it might be worth getting just a larger resin printer with a bigger build plate, to accommodate a more convenient size of timbering brick. IF you were prepared to do the whole thing loose-jawed. IF.

Just another thought to add to the mix.

But an FDM printer is useful for other things, such as the filing jigs.

cheers,

Martin.

 

[AndyB]

@Steve_Cornford

Hi Steve,

I've never used the BIBO at anywhere near the full Z capacity, and I doubt I will ever do that with the Neptune. I can't think of anything 10 inches tall that I might want to print for modelling.

One issue at the back of my mind which I want to resolve (and the real reason for getting the Neptune) is the X-Y resolution for this style of open-frame FDM printer -- there are a lot of them about. The BIBO claims 0.05mm, and so does even the little MINIBO. The Neptune says nothing about resolution (travel per motor step) but claims +/-0.1mm accuracy for the finished print. That's not very impressive.

On both the BIBO (and the MINIBO with Templot's backlash correction function) I've achieved very good accuracy by careful measurement and adjustment of the shrinkage settings, better than +/-0.1mm. It's important for the socket sizing of course.

I shall be very disappointed if I can't achieve the same on the Neptune by tweaking the settings. As usual it's proved impossible to get this sort of information from any website or by asking anyone, the only way to find out is to get one and see.



I hope it can be called fun. As usual with these things, the quoted assembly time is how long you will need to lie in a darkened room afterwards. The actual assembly time is always a fortnight.

I'm currently working on the loose jaw pin holder for the tweezers.

cheers,

Martin.

Hi Martin,

To improve the resolution I swapped the X and Y steppers for ones with half the step angle and used the smallest belt drive cogs available on my (now antique) Folger printer. It improved the X-Y resolution a lot.

To minimize backlash the drive belts are held in tension with tie wraps.

Cheers!
Andy

 

[ralphrobertson]

@Steve_Cornford @ralphrobertson

Hi Steve, Ralph,

IF, big IF, you were prepared to do the whole thing loose-jawed, another option comes into play. If the timbering base is resin printed, the slotted chairs could be printed integral with the timbering base instead of separate bash-fit chairs. Saving a lot of time and improving the final accuracy (e.g. for P4).

So instead of getting a separate FDM printer and a small resin printer, it might be worth getting just a larger resin printer with a bigger build plate, to accommodate a more convenient size of timbering brick. IF you were prepared to do the whole thing loose-jawed. IF.

Just another thought to add to the mix.

But an FDM printer is useful for other things, such as the filing jigs.

cheers,

Martin.

Hi Martin,

For me that would be great for plain track, personally I prefer the ability to be able to 'manipulate' turnouts which is why I use ply and rivet. I know ready to run works but when you are modelling in P4 I have found that some adjusting of turnouts is often required in order to get good running. The resin printer I have would need replacing if I were to do this but I do think it is an option but please finish the rest of the turnout chairing before you spend time doing this - there are a lot of people out there waiting to complete their turnouts!

Ralph