3D Printing in 2mm Scale

[richbrummitt]

7 hours ago, garygfletcher said:

 

@richbrummitt how are you finding the printer? do you have any photos? As you suggested it would be great to see some sliced files or screenshots as to what you have found the best orientation/raft options. What resin have you found most successful, I was given some water washable, so will start here, but it seems to have mixed reviews. I do have a was and cure so can easily accommodate other resins.

I’ve been using Elegoo standard grey and have not tried any other resin yet. It is still early days for me. So far I believe I’ve done enough with the printer to show that I can achieve what I might hope of it.
 

Game changer was getting a wash/cure station. I got a device to cure when I ordered the Mars 2 Pro but the washing was tedious and messy. Getting an Anycubic wash and cure and going almost straight from the printer to an automated wash is so much less mess and faff. What I have found is it’s important to get the models dry before curing, at least on any visible surfaces because liquid on the surfaces can cure in place and spoil what should be flat or detailed surface. 
 

Files I’ve previously had done at Shapeways came out well in terms of detail. 
 

 

The Beetle (right and front) is a good test piece because it has rivets, strapping, angle sections and louvres. 
 

So far I’ve printed without any inclination angle on the build and I’ve got better since breaking all the above when removing from the build plate. I had problems with prints sticking too well in the beginning. I ordered a WhamBam Systems flexible build plate but haven’t fitted it yet. I may fit it for convenience somewhen but I no longer struggle so much removing prints when they are on a raft with an angle to put the metal scraper under and if it messes up the build plate I don’t think that I can get a replacement for this size machine. 

 

I’ve sent you a file on email of 2 wagons of Ian’s design pre sliced for Mars 2 Pro. You should be able to save this to a stick and direct print in <2hr in standard resin. If the water washable has the same cure times it might also work well. There is some support structure to remove. I believe this file can also be opened in chitubox and resliced if you need to change anything, even though it’s not what the software calls a project file. One of the most frustrating things, I find, is the time effort to add supports in chitubox. The auto generated ones can be completely inadequate most times. I do wonder if the paid version has better usability/options/tools. My limited research has not drawn a conclusion. 
 

I hope to use it for all kinds of railway model things where I need multiples, up to coach sized items. I haven’t finished any new files of my own to try on it yet: no shortage of ideas, only the time to make them happen. 

[-missy-]

11 hours ago, richbrummitt said:

What I have found is it’s important to get the models dry before curing, at least on any visible surfaces because liquid on the surfaces can cure in place and spoil what should be flat or detailed surface.

 

 

I am working on a wash and cure 'station' that cures the resin whilst submerged in water. So far, the results are very promising.

 

 

Julia

[Simon D.]

On 23/12/2020 at 14:13, garygfletcher said:

My intention is to import the stl into fusion as a mesh

My experience is to avoid using mesh designs in Fusion360, it's a world of pain to convert to Brep - which is what you need.   There are YouTube videos on this or google it.  No1 daughter's boyfriend did a couple of designs in Blender as Meshes for me and while they can be imported as stl's it is impossible to convert them and manipulate. You may also end up with things called inverted normals (!), which may not print.

[garygfletcher]

2 hours ago, Simon D. said:

My experience is to avoid using mesh designs in Fusion360, it's a world of pain to convert to Brep - which is what you need.   There are YouTube videos on this or google it.  No1 daughter's boyfriend did a couple of designs in Blender as Meshes for me and while they can be imported as stl's it is impossible to convert them and manipulate. You may also end up with things called inverted normals (!), which may not print.

I won’t be using the mesh, just a method of interrogating/reverse engineering dimensions etc as stated. 

[Trofimow]

On 23/12/2020 at 17:30, Ian Morgan said:

If anyone wants to give this LBSCR 5 plank open wagon a try, let me know how it goes. If it is workable, I will push it to the 2mm website.

 

I took the liberty of blowing this up to 4mm and running it on the photon with very acceptable results.

[Ian Morgan]

Hey, that looks pretty good Trofimow. I had set the wall thickness at 0.7mm (for Shapeways), so the planks might be a bit too wide, which might show up more in larger scales.

[Trofimow]

55 minutes ago, Ian Morgan said:

I had set the wall thickness at 0.7mm (for Shapeways), so the planks might be a bit too wide, which might show up more in larger scales.

 

Yes, the sides have come up a bit thicker than would be ideal in 4mm, but apart from that it seems pretty good to me.

[-missy-]

3DP Class 04 wheels fresh off the printer.

 

 

Thanks to @2mm Andy for the resin supply

 

Julia.

[-missy-]

Hi.

 

Very happy with these. 8.5mm Austerity wheels now done too. The resin really suits this particular application. Dimensionally they seem to be within 0.05mm too (but I add material on for a machining allowance anyway).

 

 

Julia.

[richbrummitt]

1 hour ago, -missy- said:

Hi.

 

Very happy with these. 8.5mm Austerity wheels now done too. The resin really suits this particular application. Dimensionally they seem to be within 0.05mm too (but I add material on for a machining allowance anyway).

 

 

Julia.

Are these for casting or do you have a cunning plan to use them as is?

[-missy-]

1 minute ago, richbrummitt said:

Are these for casting or do you have a cunning plan to use them as is?

 

Hi Rich.

 

The class 04 wheels will certainly be used as is, not quite so sure about the J94 wheels yet.

 

Julia.

[richbrummitt]

13 minutes ago, -missy- said:

 

Hi Rich.

 

The class 04 wheels will certainly be used as is, not quite so sure about the J94 wheels yet.

 

Julia.

Thanks Julia, 

 

I would love to see how you arrange the plastic stub axles into the frames. 
 

What is your concern with the larger wheels?

[-missy-]

12 minutes ago, richbrummitt said:

Thanks Julia, 

 

I would love to see how you arrange the plastic stub axles into the frames. 
 

What is your concern with the larger wheels?

 

Hi Rich.

 

In this instance, the stub axle is there purely as a workholding feature so I can put it in the lathe and machine all the features of the wheel in a single setup. The 04 has metal axles so the wheels will be drilled to suit.

 

The only thing I have experienced with larger diameter wheels in the past was the strength of the rim in relation to the axle, especially with near to scale spokes. I would be much more confident trying something larger using this resin though. I think it would be well suited for smaller items like axleboxes, buffers, etc too.

 

Thanks to David for doing the R&D with it!

 

Julia.

[Crosland]

29 minutes ago, -missy- said:

The only thing I have experienced with larger diameter wheels in the past was the strength of the rim in relation to the axle, especially with near to scale spokes. I would be much more confident trying something larger using this resin though. I think it would be well suited for smaller items like axleboxes, buffers, etc too.

 

The 3DP wheels in the kits from "2mm Locomotives" were very fragile. I replaced them with association wheels but still haven't gone back to finishing a kit.

 

Andrew

[-missy-]

43 minutes ago, Crosland said:

 

The 3DP wheels in the kits from "2mm Locomotives" were very fragile. I replaced them with association wheels but still haven't gone back to finishing a kit.

 

Andrew

 

Hi Andrew.

 

I think a large part of that was down to the material used for the printing. I am pretty sure he used shapeways for his supply at the time, an awful lot has moved on since then.

 

Julia.

[richbrummitt]

26 minutes ago, -missy- said:

 

Hi Andrew.

 

I think a large part of that was down to the material used for the printing. I am pretty sure he used shapeways for his supply at the time, an awful lot has moved on since then.

 

Julia.

New materials, processes etc. constantly change the playing field. I did the work on a universal CAD model for an any size / type wheel around 10 years ago but the manufacturing possibilities available then did not scale down to match the quantity we would use. At that time Metal Injection moulding looked like it would do an excellent wheel in stainless steel but the tool costs were an insurmountable barrier. 3D printing in metal was pretty new at that time and crazy expensive. Wheel centres would have been £100s each.  Now this process is available at prices that allow one off sets of wheels (still with some compromise on surface finish) in stainless steel and without 4-5 figure sums for tooling. 

Materials disappear too: that eSum resin seems to have vaporised and it seems was the best of the best for mechanical properties in ABS like resin for DLP 

[-missy-]

The only thing about that resin is it states this on the manufacturers website...

 

 

http://www.esun3d.net/products/242.html

 

Anyone have any ideas? My oven doest go that low.

 

Julia.

[richbrummitt]

5 hours ago, -missy- said:

The only thing about that resin is it states this on the manufacturers website...

 

 

http://www.esun3d.net/products/242.html

 

Anyone have any ideas? My oven doest go that low.

 

Julia.

The graduations on our oven start “defrost , 90, ... “. Defrost could be fan only without heat in reality. It might go as low as 50 but would need an oven thermometer or pyrometer to check. They’re pretty cheap. Ovens are pretty simple devices really: they just heat until the thermostat determines ‘too hot/hot enough’ and back on when the same determines ‘too cold/cold enough’ and are not spectacularly accurate. 
 

Perhaps a heater box is next on your project list? 

[MikeTrice]

Perhaps heat in water in an old pan (and don't use it again for food) on the stove. Thermometer probably a good idea.

Edited December 27, 2020 by MikeTrice

[monkeysarefun]

Not sure if this or the equivalent is available there but I've had great success with it, its definitely a quantum leap up in strength compared to the brittleness of regular resin.

 

https://monocure3d.com.au/product-category/rapid-tuff-resin/?v=322b26af01d5

[animotion]

On 23/12/2020 at 18:26, TomE said:

Well I knew I was pushing it with 0.4mm thick sides & ends, and I was right. Will have to thicken them up slightly & try again. On the plus side the details came out great! 
 

 

Tom. 

Judging by the quality of the print printing the side at .4mm thickness was pushing the bounds of the printer. If the wagon is going to be a loaded one of have a sheet over it then I would think about redesigning the wagon so that the sides and floor could be printer flat and assembled like a kit. I don’t do much 2mm printing but here is a loco I did the artwork for and printed on my printer.

[Ian Morgan]

Steelman Royale?

[TomE]

On 02/01/2021 at 22:13, animotion said:

I don’t do much 2mm printing but here is a loco I did the artwork for and printed on my printer.

 

Looks great! What printer are you using?

 

The next project for me is Handyside Bridge, the former Kings Cross footbridge, which spans the yard at Ropley:

 

 

Tom. 

[animotion]

3 hours ago, TomE said:

 

Looks great! What printer are you using?

 

The next project for me is Handyside Bridge, the former Kings Cross footbridge, which spans the yard at Ropley:

 

 

Tom. 

Hi Tom

That looks like a tall order,excuse the pun, to 3D print depending on what printer you have and gauge you are printing it in. I can print down to 10 microns on my Nova3D printer but haven't tried anything that challenging yet. The test will be to see if it prints straight, you will probably need supports for the brackets. Printing it vertically would give you the best results if you can do it with the least number of supports to remove.

[TomE]

2 hours ago, animotion said:

Hi Tom

That looks like a tall order,excuse the pun, to 3D print depending on what printer you have and gauge you are printing it in. I can print down to 10 microns on my Nova3D printer but haven't tried anything that challenging yet. The test will be to see if it prints straight, you will probably need supports for the brackets. Printing it vertically would give you the best results if you can do it with the least number of supports to remove.

 

This is for N Gauge, and is 47mm tall. I have printed an earlier version, albeit not the full height and without brackets, with success so it should be ok. The mono x is doing it's thing as I type, so in about 10 1/2 hours we'll find out! 

 

Tom.