FDM chairs in 0 gauge - 7mm COT track

[Martin Wynne]

Fair enough you don't have to go down that path, equally we should not simply dismiss it as will not work end of story.
For all we know there are 2mm guys doing exactly that right now. After all there are quite a posts from 2mm models saying the curling is not an issue for them. ( has to be reason for that as well)
cheers
phil,

@Phil G

Hi Phil,

You can prevent curling by sticking the prints to a bit of wood with double-stick tape while they are being cured, and for a few days afterwards. Or you can uncurl them in hot water afterwards.

More significant for me is the way even with a thermostatically controlled resin heater today's track gauge and timber thickness is not the same as yesterday's. That may be due to all sorts of things -- such as the elapsed shelf life of the resin, the weather, mains voltage, price of kippers, etc. It's just not worth the hassle, when you can just switch on an FDM printer and get what you want while you build the rest of the layout. For me the resin printer is for making the chairs, not the timbers.

cheers,

Martin.

 

[Martin Wynne]

Thanks. Is it that specific Wood colour, or any Sunlu PLA+ ?

@JohnB

Hi John,

I got better results with that colour than others, but that may just be a lucky reel. I have obtained two more reels of the same but not tried them yet.

Sunlu also have a budget brand of PLA-Plus called JAYO -- 10% more on the reel (1.1kg) and lower cost, but it is definitely inferior for COT track. OK for filing jigs and plug track bases:

https://www.amazon.co.uk/gp/product/B0CHV5P8RL

Previously I have used several colours of eSUN PLA-Plus, which is fine for plug track bases, but Sunlu seems to have the edge for COT track.

It's impossible to try everything -- please report your findings.

cheers,

Martin.

 

[Martin Wynne]

.
Test COT print with the Orca Slicer just finished.

TOTAL FAILURE -- chairs are just a pile of broken bits.

That was with a standard Orca fine profile for the Neptune 4 printer.

I will try again, using similar settings as Cura. I can already see some changes needed -- the Z-hopping needs to be turned off, and the retraction is excessive. It took a long time because the ironing was extremely slow at a snail's pace, and the results of it are not good -- excessive over-extrusion on the timber tops.

If it can be got right it will be worth doing for the option of varying the profile with height.

cheers,

Martin.

 

[Hayfield]

Martin

I was going to ask about various makes of filament, the first reel I used was Esun PLA+ using my Kingroon, somehow I then ordered Anycubic PLA+ for my Kingroon,

With my Neptune4 I am now on my second reel of PLA+. I get the impression that my Neptune4 with Esun PLA+ makes less fragile chairs in 7mm scale, but this may be down to the printer father than the filament. I have also got the impression that the chairs are more pliable in COT track than plug track

As 7mm scale is often used out doors would it be useful to try ASA

https://www.amazon.co.uk/eSUN-Filam...628459772-B0CQRBBDLG-&hvexpln=74&gad_source=1

If so what make and are there different grades ?

 

[Steve_Cornford]

Hi John,
Under properties , did you see the [warm tip]?

High shrinkage, whatever that means.

Steve

 

[Martin Wynne]

Martin

I was going to ask about various makes of filament, the first reel I used was Esun PLA+ using my Kingroon, somehow I then ordered Anycubic PLA+ for my Kingroon,

With my Neptune4 I am now on my second reel of PLA+. I get the impression that my Neptune4 with Esun PLA+ makes less fragile chairs in 7mm scale, but this may be down to the printer father than the filament. I have also got the impression that the chairs are more pliable in COT track than plug track

As 7mm scale is often used out doors would it be useful to try ASA

https://www.amazon.co.uk/eSUN-Filam...628459772-B0CQRBBDLG-&hvexpln=74&gad_source=1

If so what make and are there different grades ?

@Hayfield

Hi John,

For outdoor use the PLA-Plus may be ok for a several years if given a good coat of paint. Such as a spray all over with rattle-can primer before laying, including the underside, and then a fresh coat of track colour every year. But I haven't tried it, and until someone does we still won't know the answer for a few years.

A possible alternative would be laser-cut timbering in external-quality plywood, and FDM (or resin) plug-in chairs. Likewise well-painted.

I haven't tried other types of FDM polymer, so I know no more about it than anyone else can read on the labels and web sites. It seems that ASA needs a higher nozzle temperature around 260degC and a hotter build plate around 100degC (and the fans turned off). That may be pushing near the limits for an inexpensive printer such as the Neptune 4. It also needs to be done in an enclosed printer with a built in thermostatic heater for a constant internal temperature. So for the Neptune 4 it would be necessary to build some form of enclosure. Putting a cardboard box over it while printing may be enough, but the only way to find out would be to try it. It's also likely to be unpleasantly smelly while printing and the fumes may be toxic, or at least undesirable in the home.

The profiles I have posted certainly won't be suitable. You would need to tell Cura it is ASA and use one of the standard profiles -- which may or may not produce satisfactory COT track without a lot of further tweaking.

My thinking is that all this is a different hobby of 3D printing for its own sake, rather than simply a tool to aid railway modelling. But each to his own, as always.

cheers,

Martin.

 

[Hayfield]

Martin

Well if a painted PLA+ could last a few years, then its not a problem, certainly for someone of my years, then replacing timbers is a bit like the prototype and if costs stay the same (adjusted for inflation) its a small cost to pay. My fears after some reports is that it would decay quickly. Perhaps the odd miss-print could be put to good use (must find a spot that does not annoy the wife) in the name of science

 

[Hayfield]

Sorry I forgot to add thanks about the info about ASA

John

 

[Martin Wynne]

Martin

Well if a painted PLA+ could last a few years, then its not a problem, certainly for someone of my years, then replacing timbers is a bit like the prototype and if costs stay the same (adjusted for inflation) its a small cost to pay. My fears after some reports is that it would decay quickly. Perhaps the odd miss-print could be put to good use (must find a spot that does not annoy the wife) in the name of science

@Hayfield

Hi John,

Don't forget that prototype railway track needs regular maintenance if used out of doors (!).

So if model track is the same, it's just being prototypical.

cheers,

Martin.

 

[Hayfield]

I printed an A5 over the weekend using my Neptune 4, your latest Cura settings and Esun filament

Printing results on the first timber 8'6"
length 59.33mm
width 7.01mm
depth 3.13mm

Visually 1 string !!!!

Time taken about 30 mins over the projected time of 4h50m

projected weight of filament 70g
Printed weight 59g

Did it use less filament or is moisture lost during printing ?

 

[Martin Wynne]

projected weight of filament 70g
Printed weight 59g

Did it use less filament or is moisture lost during printing ?

@Hayfield

Hi John,

Most likely the weight per mm of filament set in Cura is wrong. It's not easy to check:

1. Measure out a known length of filament. Leave it somewhere warm for a week to dry out completely. Measure it's length again, exactly.

2. Weigh it, accurately.

3. Calculate the weight per mm.

And after all that the prediction from Cura is still likely to be wrong, if Cura thinks the diameter is exactly 1.75mm and it isn't.

It's best to treat Cura's figures as just a best guess, as for the print time.

cheers,

Martin.

 

[Steve_Cornford]

Weigh the reel before printing, weigh after, does difference equal weight of finished article?

Are you going to Uckfiield this weekend?

Steve

 

[Martin Wynne]

projected weight of filament 70g
Printed weight 59g

@Hayfield

Hi John,

On the Neptune 4, most of the explanation is here:

Which means the projected weight was actually 94% x 70g = 65.8g

The rest of the difference may be down to your filament being slightly under-size.

For more about this, see:

https://85a.uk/templot/club/index.php?posts/13619

cheers,

Martin.

 

[JohnB]

It seems that ASA needs a higher nozzle temperature around 260degC and a hotter build plate around 100degC (and the fans turned off).

I think my Qidi Q1 Pro is the only moderately priced printer with a heated enclosure currently available, but having read the safety information, I'm not volunteering to test ASA, even though the printer could handle it. The printer is at the far end of the room containing my toxic fumes and death ray emitting machines, so will be difficult to ventilate outside. I still haven't installed fume extraction for the laser and resin printers, plus my airbrush booth, as it will be quite complicated, so the FDM printers will be confined to relatively safe materials.

 

[JohnB]

I got better results with that colour than others, but that may just be a lucky reel. I have obtained two more reels of the same but not tried them yet.

I could only find the Wood colour on Amazon, who I don't like buying from as they are always trying to trick me into signing up for Prime, and one day they might succeed! So I've ordered Sunlu PLA+ in grey from eBay. I prefer a neutral colour that I can use for printing lots of things, so I will spend some time doing all the calibration tests to tune the settings for my printer, and see what happens with the COT track.

 

[Hayfield]

Weigh the reel before printing, weigh after, does difference equal weight of finished article?

Are you going to Uckfiield this weekend?

Steve

Steve

No one has asked me its the best part of two hours drive each way, would I be useful or needed ?

 

[Hayfield]

Weigh the reel before printing, weigh after, does difference equal weight of finished article?

Are you going to Uckfiield this weekend?

Steve

Steve

Can you see me going to all that trouble !,

I will pay more attention to what the printer is saying,

I thought the glass symbol was a suggestion to sit down with a glass of wine and wait for the printer to finish

 

[Steve_Cornford]

Hi John,
Sorry, I assumed you were local for some reason.

I am going on Saturday, so will winter my services to James.

That should leave you free to carry on your COT experimenting. Happy printing.
Steve.

 

[Hayfield]

Steve

As plug track grows I think it might be an idea of having a list of Temploters who are willing to demonstrate Templot 2D & 3D, I don't quite know how it would work or how we would deal with exhibition managers,

I think somehow we must be careful about using the Templot name. At Scaleforum we were described as "track builders" though there was another modeler demonstrating track building and using Templot templates

Certainly for the likes Expo EM and Railex (at Stoke Mandeville) you have the right type of visitors. COT track would be very well received at some 7mm shows. There is a Scale7 meeting at Albury (more of an informal gathering than a show) in Hertfordshire I have been to in the past 2 years and I think it would be a good idea to have a table showing our results and perhaps a printer working. last year someone was showing their own experiments using plug track, which caused some interest

Lets face it, Templot seems the gold standard for track builders as far as 2D is concerned, a very well respected tool which I think is now used by far more folk than we think. Plug and COT track are in development, so rightly Martin is cautious in what we do,

I think the next step is to have a small diorama with a working loco, and certainly James is not too far off in P4, 7mm needs a bit more space but we now have turnouts and plain track,

My thoughts are with the diorama/test track, it would be good to show its compatible with RTR track. Also something with a bit of scenic attention would be nice, but then I have a sales background

I guess we will just have to bide our time

 

[Phil O]

Hi, John and Martin, and others,

I'm willing to demonstrate 2d Templot, I'm a little familiar with 3d Templot, with what James and John have produced and displayed at Scaleforum. I would only charge reasonable expenses, more towards overnight accommodation, than fuel costs. The more notice the better.

 

[James Walters]

Just for info,
I will be at Uckfield as part of the Scalefour South-East activities. I'm scheduled to be there on the Saturday morning and Sunday afternoon. The organisers are rotating the demo's. Also, I will apparently only have half of a 6 foot table, so will only have my laptop and a few samples on display.

 

[Steve_Cornford]

Hi James,
I will see you there on Saturday morning for a catchup then if your time permits.
Hope you are fully recovered.

 

[Hayfield]

My experimenting in fudging the obtuse chairs for a 1-6 diamond, somehow the final check rail chairs failed to print, but did in plug track chairs, still have to form and fit the final check rails

Initially testing with a wagon

I use Exactoscale plastic H section rail joiners. plastic $8 per pack of 48 £10 for a pack of 10 cast brass fishplates

After finishing the crossing I will wire it up and test with a loco

This is an experiment and was started prior to the last update, certainly it will make building the common crossings easier, as for the center section I will either have to print some resin chairs, or get them printed.

Hopefully this will not be seen to either pressure Martin or force him into diverting his energies, rather showing that the moment the workaround works and he can have a well earned rest. Nor hopefully pushing the boundaries of the system

For the purists the K crossings are a bit of a fudge, but on the other hand its far better than I could manage to hand build or I think buy from commercial providers. With the current updates I think I can make a better job, but that's the whole idea of experimenting.

In my opinion it really shows the versality of both Templot 2D & 3D programs

It also shows the ease of build these H section fishplates allow

 

[Martin Wynne]

somehow the final check rail chairs failed to print, but did in plug track chairs

@Hayfield

Hi John,

At present check rail chairs will print only on rails 1 and 4. They can't be heaved onto rails 2 and 3. If you want them on 2 and 3 you need to overlay a partial template with them.

However, I can't see any missing in your diamond -- it's looking great.

cheers,

Martin.

 

[James Walters]

Hi James,
I will see you there on Saturday morning for a catchup then if your time permits.
Hope you are fully recovered.

Thanks Steve, yes fully recovered. I shall look forward to seeing you.

 

[Hayfield]

@Hayfield

Hi John,

At present check rail chairs will print only on rails 1 and 4. They can't be heaved onto rails 2 and 3. If you want them on 2 and 3 you need to overlay a partial template with them.

However, I can't see any missing in your diamond -- it's looking great.

cheers,

Martin.

Martin

I have been out all day and up very early so knackered, and thank you for the comment. As discussed its a bit of a fudge, but we have a crossing looking far better than anything else commercially available

Re the missing chair, using a partial template, if the center (diamond) chair is number 1 ( X chair on the vee) chair 4 (C chair on the vee) only printed the chair base, no jaws. I used the partial template, not chair heaving. As I said my second go making solid jaw chairs worked, also the B (partial ) chair is as you said wrong and needs a bit of filler. It is an experiment and I can now do better

Re chair heaving as far as I can tell only S1, S1J, L1, M1 and P chairs work ?

Sorry to give you a panic attack ,but I think a single slip may be viable, but I it will take me weeks to design. Whilst its going away a bit from the concept, COT track seems very versatile and the next goal for me is to have a working test track. You can breath a sigh of relief

The only other systems that come close (Exactoscale in 4mm and Off The Rails in 7mm) are much more prescriptive in use and not freely available, certainly at least as delicate, so some of you worries from a track builders position have been the norm for years with existing products, its brought the fun back into track building

 

[Phil G]

@Martin Wynne @Hayfield
Hi Martin and John are you saying you can crate a diamond by making a partial template and then merging this to one single STL file?

My way of Kludging 4mm plug track to make diamonds, using laser made timbers was to export the DXF file and then manually change the socket size of the chair that needed changing (heaving) in either cad or lightburn. Then print the extra required chair (from the borrowed location) that then need modifying. (cut and fill) Or alternatively modify the chair to be kludged in CAD, as in reality its just a cut and splice operation with a bit of add in to cover the no longer required loose jaw slot. and then print out the STL
Clearly you can't do it that way in COT.
Cheers
Phil,

 

[JohnB]

Or alternatively modify the chair to be kludged in CAD, as in reality its just a cut and splice operation with a bit of add in to cover the no longer required loose jaw slot. and then print out the STL
Clearly you can't do it that way in COT.

I haven't really got my head round much of this yet, so may be misunderstanding what the issue is, but I think that in Orca Slicer (or Prusa Slicer) you could import an STL of the missing chairs, and combine them with the COT track. It's quite fiddly to get positioning accurate, but could be practical. I use the slicer to do simple modifications to STLs as it makes a cleaner job of it than my attempts to do it in Blender, which is what I've also tried.

 

[Martin Wynne]

Hi Martin and John are you saying you can crate a diamond by making a partial template and then merging this to one single STL file?

@Phil G

Hi Phil,

Yes, this is the kludge method which John is using. All in one STL (but not the whole diamond, it won't fit on the printer). He's made a great job of it:

You leave out the splice rail (red), and add some filler to disguise the empty chair space.

There is a scruffy bit of video here: https://flashbackconnect.com/Default.aspx?id=2T9d6vRHd4gUwuZWOI2hSQ2

More info:

https://85a.uk/templot/club/index.php?posts/10760

https://85a.uk/templot/club/index.php?posts/10762

cheers,

Martin.

 

[Phil G]

@Phil G

Hi Phil,

Yes, this is the kludge method which John is using. All in one STL (but not the whole diamond, it won't fit on the printer). He's made a great job of it:

You leave out the splice rail (red), and add some filler to disguise the empty chair space.

There is a scruffy bit of video here: https://flashbackconnect.com/Default.aspx?id=2T9d6vRHd4gUwuZWOI2hSQ2

More info:

https://85a.uk/templot/club/index.php?posts/10760

https://85a.uk/templot/club/index.php?posts/10762

cheers,

Martin.

I agree it does look very good
cheers
Phil

 

[Hayfield]

Rightly Martin wants to design a system that automatically designs the correct chair for the correct position, at the moment and for the foreseeable future these chairs will not be available

Lets take a step back and look at where we have come from, modelers have for years put up with what's available.
Copperclad construction, no chairs
Standard C&L only recently have they had S1L and L1 chairs in 4&7mm scales
Exactoscale in 4mm scale have check rail chairs, common crossing chairs, additional slide chairs (P1-P4) obtuse chairs, M1 chairs and slip chairs, who uses them ? I do but so few people do especially when they are only supplied by 2 societies
Off the Rails did supply some specialist chairs in 7mm scale via Shapeways, now I think unavailable

So it the terms of a track builder the fudge has always been there and don't forget the largest RTR track system has only just releases an 00 bullhead track system.

Originally I was planning to build a diamond crossing and slips to EM gauge using plug track and Exactoscale parts, but my interest in 0 gauge and COT track has taken over. Later today I will finish the diamond and not only test it under power, but perhaps replace the missing bits with some cut up chairs

I don't want to upset anyone or push the methods too far, but with what we have at the moment I think a slip is possible and most of a 3 way (if nothing else the filing jigs for all 3 crossings and switches will make things a whole lot better

Using loose jaws is a much better method inconjuction with COT track, but we are not there yet, we are probable in a situation prior to the automatic slip and threeway short cut programming, we will have to return to using the partial template and the odd spot of glue, so a bit of kit bashing sometimes helps sometimes

 

[Martin Wynne]

Rightly Martin wants to design a system that automatically designs the correct chair for the correct position, at the moment and for the foreseeable future these chairs will not be available

@Hayfield

Hi John,

After you said there was nothing else available in 7mm scale, I found this (and also noticed the price):

https://anticsonline.uk/Product/Pec...e-124-Bullhead-Electrofrog_SL-E794BH_N1038562

Which looks a bit daft with the double timbers at the centre in bullhead. Even in FB there should be a gap between them.

I think "not in the foreseeable future" is being a bit pessimistic. For 12 months now I have been saying "when I get the K-crossing chairs done", and I think it's high time I got on with it.

I'm so impressed with what you have done with the existing 4-sided rectangular chairs, I'm wondering if I should switch tack and do them temporarily using the existing compromise widened cast design -- before up-ending everything to get the 8-sided chairs and slab & bracket design work done. Almost no-one has mentioned that they are not strictly correct to REA designs.

The problem with doing more and more "temporarily" is that it tends to get stuck forever. Look what's happened to the brick assemblers "temporarily" kludged into the background shapes.

Which would you prefer: wrong designs "temporarily" soon, or wait for the correct designs eventually?

cheers,

Martin.

 

[Hayfield]

Martin

Thank you again for taking interest in the project, I was mentioning the companies who provide parts, The diamond is a RTR product and like their turnouts, they have made decisions on the geometry and detail, firstly to aid manufacturing, secondly to be a universal system where a variety of wheel standards will be accepted and thirdly allow some form of ease of joining turnouts and crossings easily together

I did indeed forget Peco have a small selection of track building parts both in 4 & 7mm. I also failed to mention Phoenix Precision selling trackwork parts in 4 & 7 mm scales, and of course Slaters plasticard. But in all cases the variety of chairs are limited and the builder is left to make the best job they can when special chairs are required

Firstly I would be happy for the right decision to be made rather than a compromise, like many I am happy to kit bash (for want of a better sentence), but then I am just about succeeding with partial turnouts

My Christmas whish list
1 A working test track
2 A working scenic cameo
3 Making a slip
4 making a 3 way

I cannot unfortunately assist with either programming or engineering, but have a few track building skills and happy to try out ideas

Also when it gets to kit bashing and scenic maters, could we print chairs without plugs, Nice to see a few chairs scattered about at the side of the tracks (untidy platelayers) very prototypical

In short you have designed a track building system far beyond my expectations

 

[Phil G]

Which would you prefer: wrong designs "temporarily" soon, or wait for the correct designs eventually?

Hi Martin,
Personally speaking 100% wait and get it right the first time. As you say temporary kludges tend to become, if not exactly never happening, they do get push right down what currently seems to be growing project list. And ultimately become I wish I had done statements further down the track.
cheers
phil

 

[Martin Wynne]

Also when it gets to kit bashing and scenic maters, could we print chairs without plugs, Nice to see a few chairs scattered about at the side of the tracks (untidy platelayers) very prototypical

@Hayfield

Hi John,

You can already do that, in resin ideally but also in FDM.

Also to have a neat stack of chairs outside a p.w. hut, or a wagon load of scrap chairs.

But make sure to print them with keys omitted. Odd chairs lying about with the keys still in them look a bit daft -- which is what happens if you use C&L or Exactoscale chairs.

Untick this, and store the template:

Set chairs only, and untick this:

Although the button says resin, you can use the STL for FDM -- accurate rail fit isn't needed for scenic chairs.

Attached is an STL file for 7mm S1 chairs without keys (already mesh-fixed in 3D Builder), ready for Cura:

They will be printed directly on the build plate -- use a good film of glue for FDM -- 9 minutes on Neptune 4.

p.s. test FDM print just finished -- 10 minutes. Looking good -- you don't often see model chairs without keys.

Strictly speaking we should omit the screw heads too (but you won't get any holes), and they look a bit odd:

I will look at an option to omit the screw heads only, and leave the screw bosses. (It can be done now in the DXF.)

If it's just a few chairs for scenic use, you could snip the screw heads off.

cheers,

Martin.

 

[Hayfield]

Testing went well with 2 RTR and 1 kit built loco

RTR Ixon and Dapol plis a kit built loco with Slaters wheels, all ran fine

Finished as far as rails are concerned, just need to sort out the chairs in the crossing

Templot goes into scenery, key less chairs to add detail to the scene

Perhaps how they may be seen at the side of the track

Templot 3D just keeps giving

 

[Rob Manchester]

Templot goes into scenery, key less chairs to add detail to the scene

View attachment 12079

Perhaps how they may be seen at the side of the track

Hi John, Martin,

Good work, both of you. I agree about omitting the keys but if the chairs are thrown about around the scenery ( as replaced items ) shouldn't they have the chair screws missing too ? Even if they are part of a new delivery to a job site the chairs wouldn't have the screws in....?

Rob

 

[Phil G]

Hi Guys,
Been playing around a bit today, please find attached both 4mm and 7 mm scale S1 chairs no key and no screws STL files note both have been mesh fixed. it is a single chair, you will need to clone in either Cura or Chitubox. 3D builder screen shot also attached
should I post to resources?

cheers
phil

 

[Phil G]

Hi Guys,
Second set of S1 chairs this time with no screws or ferrules I also noticed I had left a lip of key on the originals so this have been removed as well
cheers
Phil

 

[Martin Wynne]

@Phil G

Hi Phil,

For REA the screw hole is much larger than GWR and tapered, to allow for the fitting of a ferrule (originally oak, now plastic):

© Eric Ramsay

cheers,

Martin.