My printing progress (WAS: My first print attempt)

[Chris333]

I just pour the next bottle in no matter what color and mix it with a chip brush.

[bbussey]

I did that with the beige-to-gray changeover, but I need a clear window test. Stil two or three prints away from finishing the gray.

[SkipGear]

I did that with the beige-to-gray changeover, but I need a clear window test. Stil two or three prints away from finishing the gray.

Have you decided how you are going to print the windows? I was thinking about printing flat, directly on the build plate, then sanding and polishing the plate marks out of the back side of the windows. I worry about sags and distortion if I support the window inserts. Also planned on printing a raised edge around the windows to represent the frame and make it easy to paint.

[bbussey]

I was thinking horizontal but with the membrane support around each window. But flat on the build plate definitely would provide glass-smooth faces on both sides, as my build plate is still scratch-free. My only concern would be getting the parts off the build plate. Maybe adding the 30-degree reverse bevel that Chitubox puts on their auto-generated bases would be enough to get it off the plate. I’ve been adding the bevel to the bases of the last sets of models I’ve printed and they pop right off with very little prying from the plastic scraper. It also would have the advantage of printing in five minutes.

[bbussey]

The latest test prints. P&LE Breadbox coil car, and C&O F9 well car. I missed adding some supports on some corners on both models. The final F9 underframe would be 3D printed in metal, either brass or stainless steel.



It’s pretty cool that the plate and ratchet detail can be seen even before priming.



Still some gray in the tray, currently sitting at the min level line, so I may print some flatcars. I’m learning though that it is best to print everything at an angle to avoid a “pillowing” effect on the bottom faces, unless the faces will be hidden from view.

[bbussey]

Stone’s Express trailer (Strick 35’ drop-frame) on New Haven 40’ flat.

[GonzoCRFan]

Watching this thread with great interest, hoping the G36 and 132Bs are more than just personal projects...the clamshell coil car is damn cool too.

[amato1969]

@bbussey you are killing it!!!

  Frank

[bbussey]

G32B and G36 are eventual ESM MIA kits, G32B holdup is the availability (or lack thereof) of A-3 truck frames so G36 might jump ahead now that I can render smooth sides.  Debating on whether or not to do the hooded G36 version.  Xm-4 Transco also MIA kit but numerous issues with that still.  The trailers eventually will be a new ESM product line, timing depends on procurement of TWX parts, might rework for MTL parts in the interim.  Haven't decided yet on the breadbox or the Canstock.  Still trying to get the ex-RYM G41 to a reasonable cost also, maybe castings from a 3D-printed master would be the best option.

[wazzou]

I've had a CB&Q Transco sided Boxcar on my back-burner to do list for years.

[bbussey]

G41c coil car. Transitioning to transparent green.



Not bad for the first attempt. Some tolerance issues but nothing that can’t be fixed.

[Chris333]

Did you wear the screen out yet? 

[bbussey]

Not yet!  I have spare FEPs for when I do.

Rerunning the Strick drop-frame trailer overnight after the latest revisions.

[bbussey]

Still trying to perfect the trailers, specifically the Strick drop-frame. This is the sixth attempt at trying to eliminate assorted distortion and bowing. Starting with the third attempt, the membrane worked perfectly at eliminating curl-up. I’m still getting some wave in the sides even though I have six rows of cross supports 2mm apart. But now at least it’s subtle and has the appearance of sheet metal. I think I’ve got it but the transparent green makes it a little tougher. I’ll know for sure after these are de-sprued, cured and primed.

[Chris333]

Anything that changes the surface tension of the FEP can cause a ripple. Like if you had a lip inside those trailers for the floor to fit to. It would print the layer without the lip and then the very next layer will have the lip and that is a lot more surface area for the FEP to stick to.

Same this with a cab that has open windows. The layers with the window openings will have less surface. Or a lower hood next to a taller cab. Right at the layer where the hood stops the cab might get a ripple.

Same if you print a short item right next to a taller item.

In this photo


Above the Brookville plate to the right is a ripple. That is the lower part of the floor causing it. And At the top of the hood you can see a ripple in the cab at the front. Most of it goes way at an angle, but then takes longer to print.

It's just figuring out how it works and planning ahead before printing. Of like me just print it and then look at the print and see what can be improved.