My printing progress (WAS: My first print attempt)

[SkipGear]

Chris is right about the surface tension, taking the cross bracing out will probably cure it. The caboose prints had the issue at the inner step in the thickness where the floor keyed in and where the roof, pitch started but fortunately that only showed on the ends and it was under the porch roof so you couldn't really see it. Adding the web support in the step at the front and back of my body would probably help eliminate the wave at the bottom edge. The only inner supports were vertical to keep the roof from sagging before the two sides of the peak met. In early tests without the center supports, there was a big wave there at the transition where the left and right sides met as the peak was built.

[bbussey]

I figured it was FEP surface tension and just kept experimenting until I got results I could live with.  I had to add cross bracing in general because I was getting bowing. The last changes I made were to add sturdy cross bracing on the drafted frame to keep that vertical and help keep the lower trailer sides vertical, and the circle cutouts so that the uncured resin could drain out before popping the prints off the build plate.  I also thickened the sides of the trailer by 1mm.

[Lemosteam]

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.

I can see some droop of the roof lip between the vertical ribs too.  Maybe draft that back to the sides so that there is a gradual thickening of the roof from the side to the edge (outside the panels)

Also I would like to express gratitude for all your experimenting here- it is saving me from my own experimentation which had me very dejected and the reason why I have not been printing all that much (or commenting about it).

[bbussey]

I think the roof droop is an illusion of the light playing off the transparent green resin. I haven’t seen any evidence of that with any of the resins I’ve used so far. The green is the sixth print of the model (beige twice, gray once, gray/green twice, green once).

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My main issue has been bowing and fan out at the lower edges, which I believe I’ve eliminated with the latest attempt. I probably can minimize the rippling effect more by putting the cross supports directly behind the vertical ribs. I will try that next if the rippling effect on these prints is not passable. But these look pretty good to me after initial inspection.

[bbussey]

I’m not dejected or deterred. Pretty excited actually. Just as it took some experimentation to learn how to get around the quirks of ProJet 3000 print rendering (ie Shapeways FXD), there are ways to combat these quirks as well. So far it’s been much easier than finding the sweet spot for the ProJet prints.

[Lemosteam]

I think the roof droop is an illusion of the light playing off the transparent green resin. I haven’t seen any evidence of that with any of the resins I’ve used so far. The green is the sixth print of the model (beige twice, gray once, gray/green twice, green once).

Ah that makes sense!

What you are doing is quite prolific.  I just don't have the time (just ask my wife).

[bbussey]

I primed one, it looks great ... except I forgot to add the marker lights, taillights and rear bumper.
 

[bbussey]

FGE ex-PRR R7 reefer.  Body and floor one piece, separate roof and hatches.  Detail parts will come from InterMountain (reefer hatch latches), Micro-Trains (vertical brakewheel, trucks, #1015 coupler parts), and BLMA (18" grab irons, drop and straight).  Still needs etched parts (ladders, roofwalk, letterboard, coupler box cover).  Hatch design similar to MTL and IRMC in that the hatches can be positioned opened or closed.  First attempt, needs some minor tweaking, although this probably is salvageable.

[Chris333]

Hows about making that into a boxcar. I haven't heard from M4D lately.

[CodyO]

Awesome work @bbussey!

[Ike the BN Freak]

Watching this thread is making me want to go and learn how to design my own. I figured it will probably be the only way for me to ever get a bunch of the correct cars for my BN executive train.

[Sokramiketes]

Dang, Bryan.  I didn't know you were such a prolific designer.  I feel like we need to find you some backing capital to keep moving. You're skills are on the front end of these projects!

[Chris333]

Well if he can design injection molded kits...

[bbussey]

Exactly!  Who do you think is designing all the ESM product? 

[bbussey]

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.

@SkipGear Tony, I ordered this off Amazon last night. It won’t be here for a few weeks but I have other things to keep me occupied in the interim.     This supposedly produces crystal clear results with no yellowing. I’m going to try printing the windows flat and see what happens. This will open the door to multiple projects if it works. The reviews are overwhelmingly positive, and the negative reviews refer to things that aren’t relevant to rendering windows.

NOVA3D 3D Printer Resin Ultra-Clear 405nm Rapid Curing Resin Designed for Monochrome LCD 3D Printing 500g

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