3D Printing in 2mm Scale

[Sithlord75]

The 12t van body now comes in plywood...

 

[A. Bastow]

1 hour ago, Sithlord75 said:

The 12t van body now comes in plywood...

 

 

Kevin, you're steaming ahead with these designs at the moment! 

 

Making me feel bad for not doing anything with mine! Might have to have a night or two next week working on them. 

[nebnoswal]

An update to the other downunder 3D printworks.

 

Presently I've 6 wagons nearing completion.  On the left left-hand side are a LMS Prized Cattle Wagon (PCW) and a LMS Meat Van.  These have been both been drawn to N gauge (1:148).  The PCW (page 98, Tatlow, for those playing at home) is designed to plonk straight onto a Farish 11' cattle wagon chassis.  It needs a dose of crimson, once I can find some.  The meat van was drawn while I was away playing war games late last year, so unfortunately my reference chassis at the time was a Peco 9' WB .  http://Sithlord75  will doubt have a play with these and shrink to 2mm.

 

 

In the center are S&DJR Horseboxes (short and long) , which are on request from queensquare (yes, they are 2mm) .  The short will sit on a 8'6" chassis and the long on a 11' chassis.  We ordered some last night, so once they arrive this can progress.  Decals will be the next challenge.

 

On the right/below are a S&DJR 8/10T large cattle wagon and a 10T Special Cattle Wagon.  My layout, Sturminster Newton, is a market town, and at one stage had the biggest livestock market in the UK.  Any variety of livestock wagon may have turned up there at some time, and hence I intend to have as much variety as possible.  http://Sithlord75 is of the opinion that I will eventually 3D print all of Tatlow, he maybe right!  The cattle wagon was started about 2 weeks ago and has progress pretty well.  Last week I lucky to be given access to a copy of Southern Wagons Pictorial, which had a nice chapter on S&DJR wagons, and lucky me, I found the diagrams for the the SCW, of which there were only two of.  It just required some modifications to the existing cattle wagon drawing.  Both of these will run on 2mm 11' chassis's, which are on order.

 

And before anyone asks, no, I'm still not a 2mmFs member. 

Edited April 23, 2021 by nebnoswal

[Sithlord75]

I had a few hours spare yesterday afternoon - wife home sick from work, had to taxi my kids around in the morning so day off for me too.  So what to do with a few hours???

 

Well, we all have those "Rule 1" models.  For me, the LMS Diagram 1708 coal hoppers (30 built in 1929) have been of interest for approximately 20 years.  As one of the first true "block train" as we would understand it, they were built to carry coal for the LMS power station at Stonebridge Park from Toton.  Seeing them off the line between these two places would have been rarer than finding a unicorn in your stable.  My N Gauge layout was based on St Alban's Abbey but with some modifications (chief being to make it a through station, rather than a terminus - a fairly significant mod!) and so I felt, since these wagons would have passed through St Alban's City (Midland Railway) station, it was close enough to justify.  Initial thoughts turned to modifiying German hoppers - those who are NGS members will have seen the article doing just that in the most recent Journal.  It was the arrival of the Journal which re-inspired the project and the 12 odd wagons were unearthed with a view to seeing how it went, armed with the drawings from "An Illustrated History of LMS Wagons: Volume 1" by Essery and owned by @nebnoswal.

 

As an illustration on how far my modelling tolerance has moved in the last ten years since joining to 2mmSA, it took about 2 minutes with a vernier and the book to decided it would be much better to just draw them and print, than to muck around and try and make one.  To start with, doing 12, even at 2 or 3 hours each, added up to quite a bit of time, and they'd still be wrong!  So 4 hours of work later and:

 

Test print showed a couple of areas which needed tweaking - and I've decided to put a disposable raft on the top rather than the bottom (there is a flat area on the top so it made sense) so the second print will be done upside down.  All things being equal, it will make it to the ZAG meeting tonight (Brisbane time).

 

[Sithlord75]

@65179 contacted me as he had missed the last ZAG due to travelling internationally (Wales to England!) and wanted to ask questions about the plywood SR van mentioned above.  Inter alia Simon wondered if I had printed it and if so was it smooth enough to consider other vans such as the LMS Diagram 1828?  Well I've still got @nebnoswal's copy of Essery Vol 1 and so looked it up.  

 

Ben and I have been pondering for a while about the pressed steel ends and this seemed like as good a diagram to try out some ideas on as any - and being LMS modellers we can't really have too many LMS type vans now can we?  So I scanned the drawing and had a play.  The result of a couple of hours work is:

 

 

 

 

 

I've a few more things I want to do to it - and there pictures show a variety of doors and detail parts - three private builders and their interpretations plus the LMS/BR(M) mucking around with them over the years does mean the 1000 odd examples didn't look the same.  I'll have another lot of decals to draw too I suspect - but since I've got to do the ones for the D1708 hoppers, I'll sort them together.

 

It will hopefully fit on 3-324 (I think that's the right one!)

 

[TomE]

Most recent print for me, a shoc van.

 

Tom. 

[A. Bastow]

Hi all,

 

So I will be taking the plunge and actually buying a 3d printer, rather than strong-arming friends and politely asking acquaintances to provide printing services for me. 

 

I have been eyeing up the new Elegoo Mars 3, which has a 4k resolution screen. So the question is, do I really need a 4k resolution printer or are the 2k ones such as the Elegoo Mars 2 (which produces excellent prints) good enough for the job?

 

Could I save some cash by buying a 2k printer or should I shell out that bit more for the extra resolution? 
 

Ta,

 

Adam

 

 

[richbrummitt]

I think the vertical resolution is more limiting than the screen resolution. Some 4K printers might be better for that. I recommend that you ensure that the print area is large enough for whatever you would like the machine to print. The prices seem to be somewhat proportionate to screen size and that might move the affordability scales in a particular direction. You might also decide that a wash station is essential and if bench/cupboard space is tight could impact your final decision. A mono screen is definitely better.

[bradfordbuffer]

10 hours ago, A. Bastow said:

Hi all,

 

So I will be taking the plunge and actually buying a 3d printer, rather than strong-arming friends and politely asking acquaintances to provide printing services for me. 

 

I have been eyeing up the new Elegoo Mars 3, which has a 4k resolution screen. So the question is, do I really need a 4k resolution printer or are the 2k ones such as the Elegoo Mars 2 (which produces excellent prints) good enough for the job?

 

Could I save some cash by buying a 2k printer or should I shell out that bit more for the extra resolution? 
 

Ta,

 

Adam

 

 

Get the best you can't afford!

....don't underestimate  the space you need to 3d print...printer ...wash and cure tools ipa somewhere put printer lids...etc...I went for monox and wash cure plus...8 ½lts of dirty ipa in wash tub is heavy...I put tank on garage floor while using cure function....turned round a kicked the tub over even with lin on and secured... ipa exited all over garage floor! Good job didn't listen to wife and us spare room!...

With mono x and cure I recon if you had a clear five foot work top you would still run out of room. As well as room temp and light from out side to think about.

Steep learning curve expect to use a few tubs of resin...lots of failures and then when it goes right..happy days! Plenty of free stl files on line too....before it's up to you to draw your own designs ! Think realistically might be beyond my ability

Talking of price on ebay at moment some one selling mono x at 419! Cheap as chips just bought 3 tubs of resin for 60quid ...better than 35 on amazon they arrived in 3 days.

Take the plunge it's costly...its smelly...its messy it fun...from liquid to solid...magic 

Edited October 25, 2021 by bradfordbuffer
Pic upload

[monkeysarefun]

10 hours ago, A. Bastow said:

Hi all,

 

So I will be taking the plunge and actually buying a 3d printer, rather than strong-arming friends and politely asking acquaintances to provide printing services for me. 

 

I have been eyeing up the new Elegoo Mars 3, which has a 4k resolution screen. So the question is, do I really need a 4k resolution printer or are the 2k ones such as the Elegoo Mars 2 (which produces excellent prints) good enough for the job?

 

Could I save some cash by buying a 2k printer or should I shell out that bit more for the extra resolution? 
 

Ta,

 

Adam

 

 

Ive got a Mars 3, a  Mars  and a Saturn.  Ignoring the Saturn, I've found the things that make the Mars 3 stand out over the Mars are the bigger build volume, and the way you load the vat.

 

The difference in size mightn't be much on paper but its surprising how many prints just wouldn't quite fit on  he original Mars, but would have been doable on the Mars 3. Mightn't be such an issue with N gauge.

 

The vat loading thing isn't something I realised when I bought the Mars 3, but whereas you slide it into place on the Mars, you drop it into place on the Mars 3. This just seems cleaner to me and reduces the risk of smearing any resin that might have splashed out, or of scratching the LCD screen if there is  something foreign the bottom of the vat has picked up from the workbench if you are a grot like me. Sometimes also the vat sticks to the screen, maybe its the humidity here or something but its nerve wracking sliding something between vat and screen to release it, much easier when you can wiggle it a little and lift  it upwards.

 

Print resolution wise, I cant say the Mars 3 is spectacularly better, and sometimes other variables make a bigger difference to print quality, such as printer settings or the resin quality/temperature than the difference between a 2K and 4K screen.

 

 

I bought the Mars 3 in the presale when it was $300 US with free delivery, and included $169 worth of Chitubox Pro thrown in, and I'd just got my tax return...  Not sure of the availability of the Mars 3 currently, is it in general release yet and how does the price compare?

 

IN general, if you can't get the Mars 3 then Mars 2 is an equally  worthy option, unless the extra print volume is crucial to you. Like I said, I did find myself bumping up  against that a surprising amount, but then I got the Saturn.  

 

Then again, there IS the new Anycubic Ultra DLP printer announced, and I think Mars have just released details of one in response... 

1 hour ago, bradfordbuffer said:

.from liquid to solid...magic 

 

Thats the bug that bites! Imagine, just a bottle of goo and some light and you can make a model of just about ANYTHING you can dream of, its like science fiction!

 

Edited October 25, 2021 by monkeysarefun

[njee20]

I agree with the above. The Z-axis is the same on basically all of the printers on the market (0.01mm) so that’s a red herring. Few print at the finest resolution anyway. 
 

IMO the screen resolution thing is a bit like the digital camera megapixel wars in the early days. It does make a difference yes. But it’s not massive, I’d go as far as to say indistinguishable to the naked eye for many prints. What is true is that the printers themselves definitely increment beyond the screen resolution. On paper the Mars 2 is worse than the original Mars; but it yields better prints due to better LEDs, stiffer z-axis etc.

 

I notice the Mars 2 was £180 today on Amazon. IMO that’s an absolute bargain. Still depends what you want to print - it’ll be fine for 2mm stock, but for buildings or others larger items you may want a bigger printer. Personally though I’d then go for a Saturn/Mono X.

[Sithlord75]

10 hours ago, A. Bastow said:

Hi all,

 

So I will be taking the plunge and actually buying a 3d printer, rather than strong-arming friends and politely asking acquaintances to provide printing services for me. 

 

I have been eyeing up the new Elegoo Mars 3, which has a 4k resolution screen. So the question is, do I really need a 4k resolution printer or are the 2k ones such as the Elegoo Mars 2 (which produces excellent prints) good enough for the job?

 

Could I save some cash by buying a 2k printer or should I shell out that bit more for the extra resolution? 
 

Ta,

 

Adam

 

 

Hi Adam,

 

I'd say go for the biggest screen size in terms of x and y that you can afford.  On paper the 4K will do a better job than the 2K but having looked at the prints from one of each side by side, I was stuffed if I could see what the fuss was about.

 

The x and y becomes critical if you want to print long things like coach bodies.  My Anycubic Photon will get 6 RCH 10t wagons on it and take just under 3 hours to produce them.  I can get two 75' coaches on and because of the amount of Z to fit them on, it takes over 9 hours.  A larger bed and they'd be done in a much quicker time.

 

As you'll discover if you go hunting around for recommendations and suggestions, the answers are a bit like asking about TOUs or if Joggles are necessary....

 

Cheers

Kevin

 

[A. Bastow]

These responses have surprised me somewhat, but that’s why I asked those in the know! 
 

So a “2k” printer is fine, biggest print bed I can afford and think about a wash and cure machine. 
 

Cracking! Thanks folks!

[garethashenden]

I got an Anycubic Photon a few years ago, not too long after they came out. It worked well, but I recently upgraded to an Anycubic Photon Mono. The print resolution isn't too different, the Mono is better, but the biggest difference I notice is the speed. It prints twice as fast. Part of that may be my settings, but I was blown away by the increase in speed. It really makes iterating designs much more pleasant. I will add that the wash and cure machine is indispensable. 

[Crosland]

3 hours ago, garethashenden said:

I recently upgraded to an Anycubic Photon Mono. The print resolution isn't too different, the Mono is better, but the biggest difference I notice is the speed. It prints twice as fast. Part of that may be my settings, but I was blown away by the increase in speed.

 

That's the benefit of the monochrome screen. The UV light transmission is much greater, compared to an RGB screen, allowing much shorter exposure times for each layer.

[A. Bastow]

So my 3d printer arrived and I successfully set it up and got the test model printed.

 

Got a few designs readied in the slicer and printed them off, washed and then cured. I come to them the next day to find the flat bed wagons have bowed and that there are dimples on the roof of the box van (aside from the scarring left from the supports). I am assuming that the dimpling is due to the inside being hollow and not allowing the resin to drain out during printing - would I be better off just making these solid on the inside to avoid this? Or multiple parts where the roof is a separate piece? 

As to the flat bed truck, should I have left it on the supports overnight? Did I wash it for too long? Is exposure time in the curing machine a factor? Should I just make an insert to hold it in shape while it cures?

 

The photographs are not kind to my work but they do show it rather well. 

Many thanks in advance! 

Edited November 21, 2021 by A. Bastow
typo

[njee20]

Don’t use infill, I don’t even know why they have it - it just traps resin. What’s the orientation on the van? Assuming the bottom is open then it should be ok. You have to have drain/vent holes on anything you print, or it will fail.

 

That is some pretty hefty bowing, how long did you cure it for? 

[A. Bastow]

1 hour ago, njee20 said:

Don’t use infill, I don’t even know why they have it - it just traps resin. What’s the orientation on the van? Assuming the bottom is open then it should be ok. You have to have drain/vent holes on anything you print, or it will fail.

 

That is some pretty hefty bowing, how long did you cure it for? 

 

I set the print up with the roof facing the plate but canted at an angle at which I had hoped the resin would drain.  - looks like I'll have to put a hole in the roof for filling later. 

 

The wagon was cured for about 4 minutes, but everything from the print plate was cured together. 

 

[njee20]

Shouldn’t need a hole in the roof, as long as the floor was open? Which it looks like it was.

 

4 minutes is pretty hefty, it was fine straight afterward was it? The orientation you cure in can have an effect, but I’m surprised it’s bowed inwards like that. 

[A. Bastow]

The print looked ok as soon as it was finished and directly after curing. I did leave the supports on for curing and removed them afterward. Should I have removed them beforehand?

 

I'll have to be a bit more careful in future, with my first few prints I expected some failures! 

[njee20]

I always remove supports prior to curing, it’s far less destructive as they’re very flexible. Even more so if you do it under warm water. 
 

Personally I reduce the the support contact size and depth to 0.2mm too to reduce scarring. 

[richbrummitt]

First off well done on getting some prints out. The covered wagon seems pretty close to being a great print and it has avoided any visible stepping on the roof. There will usually be some movement during curing and the open wagon has moved in the directions that would be expected. You can jig it whilst curing; insert some kind of plug. I would expect ~2min to be sufficient for curing but it will depend on how much UV exposure the surfaces are getting. It is simple enough to do a bit and see if it feels cured (not tacky) and put it in a bit longer if it needs and so on. You will get a feel for your equipment fairly quickly that way. 

 

Occasionally I leave supports on because they can help retain the shape in certain instances but this will be by design. For some models I wash and cure the prints whilst still attached to the build plate. For those models that I found required this treatment (to reduce movement during cure) I still removed many of the supports after washing.

[richbrummitt]

I’ve finally put some of my 3DP OK axle box and spring combinations on a handful of wagons. 
 

 

I’d say they look more than ok (had to get in there first with that one). The roof has been tried on for size and is clearly far too large. The wagon body is a minor reworking of an @Ian Smith CAD model. 

[Ian Morgan]

It looks like you are really getting the hang of printing now. Looks very crisp and clean (oh dear, I am turning into Kevin McCloud).

 

[CF MRC]

3 hours ago, Ian Morgan said:

It looks like you are really getting the hang of printing now. Looks very crisp and clean (oh dear, I am turning into Kevin McCloud).

 

Nah, you haven’t gone over budget yet…

 

Tim