tebee

Ah you could be right, think i got it wrong.Its 1/4 inch wider than G gauge not narrower, so 2 inches - was that gauge 2 ?

They are a nominal 1:24 scale but 1.5in gauge roughly half way between O and G scale. Oddly enough the same as Lego(near enough)

He's Tebee!

In the software I use I can resize in multiple ways. I can include a part or a collection of parts in another part and specify the ratio of original size to current size. I can adjust the size when I turn it into an STL file .It's also a parametric cad so I could write a formula to calculate the optimum thickness based on the size of the part. I don't use this as I'm printing to multiple targets ( a couple of Shapeways materials , resin printers and FDMprinters ) preferring to adjust manually. I do normally design things for 4mm scale and scale up or down from there - I use more than the minimum thickness in most cases and can easily thicken a part when scaled down if needed. Tom

Now I remember the name and that I liked the layout, but have no recollection of what sort of layout it was or why it was good. Can someone please enlighten me ?

The Minitrix T3/dock tank 0-6-0t - Like I said it was designed 12 years ago , there are probably better chassis around now. It was originally on Shapeways, this is one of a batch of resin print one I did a few years ago. There is a side tank version I did later too. Somewhere I have a picture of the original Pugbashes, but after they got wrecked coming home from an exhibition. The van was in a minor collision when a car pulled out in front of it from a side street. The stock box containing the locos went flying across it and smashed on the dashboard.

For comparison, this is the 009 version

And another 3D print, this time on a Black Anna chassis This is also sort of a pugbash twice removed . Back in 1971 or so I did two 009 pugbashs to a Kerr Stuart Tattoo style loco with a bit of Bagnall thrown in. 12 years ago I replicated this as a 3D print, Now I've taken that 3D, design reworked it as an SG saddle tank

Well Thanks. The saddle tank is actually a virtual kitbash - the boiler/smokebook/firebox tank came off an On16.5 Hunslet quarry tank and the cab is off a pug or more accurately a pugbash I recreated as a 3D print. It was your locos that inspired my friend to nudge me and remind me that I'd promised him some similar ones 2 years ago when I was building a freelance OO layout and he copied me ! The good ol' Smokey Joe is not an easy chassis to design for the motor is high at the back and that clip is wide at a bad place for saddle tanks

Are 3D printed replacement bodies bashing ? if so here 2 of mine done to fit the Smokey Joe chassis. Originally done for a friend who's building a 00 freelance layout. If you want to pint your own they are on Cults 3D as paying downloads Tom

They also made a number of G scale steam outline models

You need a watch maker rather than a repairer - I had an uncle who was one, but he retired about 18 years ago and is in his 80's now - I don't think there are many left ! Resin - think people are referring to the fact that most resins tend to be on the brittle side. However there are specialist resins that are more resilient - this is one I've used - https://siraya.tech/collections/europe/products/tenacious-eu-1kg-by-siraya-tech

It's the support structure flexing slightly during the up and downs of the printing process. I put 6 heavy supports in to minimise this - 3 along each long edge touching somewhere strong but inconspicuous. If that doesn't cure it, increase the exposure slightly, so that the supports are harder and stiffer

This just popped up on Facebook Ferrocarril Central Argentino No.9 'Cordoba' Canada Works, Birkenhead, works No.218 of 1867

because it's semi-liquid it's getting squished outward in the build plates downward stroke, you get a little extra resin traped each time which then gets part cured. Eventually this extra resin slumps downward under gravity, forming the too thick layers.

My guess is it's not actually pooling but something similar, because it's a solid mass you can't get pooling a such. It's a transparent resin, so you need reduce the exposure due to UV bleed through from the layers below. But a side effect of this is that the last few layers are not exposed quite enough as there are no layers below. Coupled with the area being exposed reducing each layer as we near the apex, those last few layers will be underexposed, more liquid and sag a little under their own weight, before being squashed outward when the build plate returns to the bottom. As the build plate rises after the print has finished, those layers will sag again giving layers of increased thickness.. I'd solve this by making it hollow, angling it front to back by 30 degrees and putting supports along the valleys and edges only

Prepping things for print is a different skill from doing the CaD work

Are you intending to print these yourself or sell the files for people to print at home? You don't get particularly good quality out of FDM printers in general - it's OK at larger scales and we've done some 4mm scale wagons that are acceptable, but I don't think you could do sellable OO scale locos with it. Resin printers are a different matter - they are not quite as good as injection molding, but better than most of the whitemetal kits out there. This is a little 009 loco I sell to fit the minitrix dock tank chassis This is straight off the printer, with just the supports removed, no cleaning up. Generally for resin printers the files don't need to be split, it's just a case of getting the orientation and the supports right - but that is an art in itself. For this little O&K coach It needs to be printed like this for the best results and ease of support removal If you do want to split files up, it's much easier to do in the original cad files, rather than trying to work with the STL's Somewhere I have an FR England loco we split up for FDM printing, but I wasn't happy with the quality we were getting - I'll see if I can dig out the files and the photos. BTW the little green tank in your Kickstarter is one of my designs - It OK you can use it, it's on the Thingiverse with free use, including commercial. Tom

If it's your first printer I wouldn't advise buying one with the larger bed size. They are slower and if you make a mistake and crack the screen it's very expensive to replace. learn how to do supports and the like on one of the smaller printers first - your mistakes will be smaller and cheaper. My choice would be one of the printers with a 6 inch mono screen. I prefer Elegoo simply because they come with vanilla Chitubox software which you can easily keep upto date. Anycubic use their own bastardized version of this which is at least one release behind - it generates much poorer supports in particular. So my choice would be the Mars 2 Pro - about £275 at the moment

And there are several new photons coming out https://www.anycubic.com/pages/anycubic-5th-anniversary

Yes main advantage for home users is it's bigger. The speed is of more interest to people using them in a production environment. For the casual user the larger size = larger vat = more resin needed. if you are only using it occasionally there is always the chance the resin in the vat might have gone off and you will waste more. And the Saturn is an untried machine,the Mars has been around for a while and fixes for it's problems known already

I missed out on the first batch, gave up and bought a Mars Not regretted it so far ! Gn15 loco

Those settings are dissimilar to mine - I'm using .05 layer height and 50% support density are the two most relevant ones I think, I use medium auto supports then add some heavy ones in the corner and anywhere else i think might distort. Reason for those two prints both being at a sharp angle is that the are both about 15mm longer than the Mars can print - it's the only way I can get them to fit !. Most of my stuff is about 15 angle and sometimes 8 or so in the other plane.

you're getting a lot more lines than me - what support structure are you using ?

Is it possible it's just that you can see the print lines more clearly on the opaque gray, where as the translucent ones let the light pass through so you don't get the shadows cast by the imperfections. I've been have problems with print lines originating from the corners of things - this seems to result in some sort of movement in model relative to fep film.