Pushing the envelope

[bbussey]

Time to start expanding the horizon.  New tests regarding the acid tankcar.  The majority of the parts will be standard resin, with the body wrapper rendered in the ABS-type resin at 0.5mm thick to start.  Might have to go thinner but I'm going to start with that.  The main core parts are designed and ready to print.  Going to try to get away with the dome not needing a wrapper.  There is rivet and grab iron mount detail, but I'm hoping the stepping is not apparent or easily sanded without losing the detail.  The dome wrapper was hard enough to handle in brass, so I'm hoping I can avoid it here altogether.  I'll start this printing sometime tomorrow, it will be finished within a couple of hours.  I still have to turn the wrapper below into a 3D part, and include the lower plate.

[Chris333]

I print steam loco boilers at 23 degrees and haven't had any stepping. Make sure the dia of the tank circle has a high number of segments.

[daniel_leavitt2000]

Bryan, have you thought about printing a bending jig for the auto rack that has been stuck in development hell for the last few years? It seems to me a printed multi-process bending jig might be the way to go. It would take a lot of resin, but you'd only need to make one or two and the process should be pretty smooth if mounted in a vise.

[bbussey]

We've thought about using a jig in the past.  Would have to come up with a foolproof design so that we don't lose any wrappers in the process.  We've lost our 28" wheels source in the form of FVM, and I think we lost our printer also, not sure on that.  Our deco backup was MTL, but that was pre-fire and pre-pandemic.  They don't have the capacity to do it now.  It's a shame because they printed the first GTW wrapper attempt and it was exquisite.  I should build one of the printed wrappers just for the hell of it, as I have all of the components to assemble it.

[Ike the BN Freak]

We've thought about using a jig in the past.  Would have to come up with a foolproof design so that we don't lose any wrappers in the process.  We've lost our 28" wheels source in the form of FVM, and I think we lost our printer also, not sure on that.  Our deco backup was MTL, but that was pre-fire and pre-pandemic.  They don't have the capacity to do it now.  It's a shame because they printed the first GTW wrapper attempt and it was exquisite.  I should build one of the printed wrappers just for the hell of it, as I have all of the components to assemble it.

Hopefully you guys can get a printer, I was really looking forward to these.

As for wheels, I see NWSL makes 28" wheels, but no photo, so I have no idea how they look compared to the FVM ones.

[peteski]

As for wheels, I see NWSL makes 28" wheels, but no photo, so I have no idea how they look compared to the FVM ones.

The NWSL makes nice wheelsets, but compare their price to FVM!  Yikes!

[Chris333]

Bryan, you should try out ESM wheelsets 

[bbussey]

We won’t have our own 28” wheels until we rerun the well cars, which tentatively is scheduled for winter 2023/24. It really can’t be justified until then unfortunately.

[bbussey]

First attempt at the new acid tank core. I don’t think the rivets are visible but I have to prime to confirm. The grab iron holes on the non-platform dome appear to be missing, but again, have to prime. Some other cheats I added for FXD have to come out and some new cheats for SLA are needed. But overall, a very good start. The body core and end caps definitely can be used as is. The dome hatch detail is strong. The only question at the moment is if the rivets and grab iron holes need beefing up.

Anxious to try the wrapper. Probably sometime this weekend.



The magnetic spring steel build plate is awesome btw.  With just a slight flex of the plate, the suction is relieved and the pieces easily slide off.  For this build, I did not include the reverse draft on the raft because I don't need it anymore to get the parts off the plate.

[daniel_leavitt2000]

We've thought about using a jig in the past.  Would have to come up with a foolproof design so that we don't lose any wrappers in the process.  We've lost our 28" wheels source in the form of FVM, and I think we lost our printer also, not sure on that.  Our deco backup was MTL, but that was pre-fire and pre-pandemic.  They don't have the capacity to do it now.  It's a shame because they printed the first GTW wrapper attempt and it was exquisite.  I should build one of the printed wrappers just for the hell of it, as I have all of the components to assemble it.

A 3d printed jig could actually be made to fit the individual contours of the etching. plastic wrap over the painted surfaces should protect the paint while in the jig. Have you contacted Kadee for painting quotes? They have similar equipment to MTL if I'm not mistaken.

[bbussey]

I don't believe that Kadee does.  The MTL test was done with the same printer they use for the 4C projects they produce now such as the weathered rolling stock.

The folding jig is the least of the issues for that project at the moment.  To start – no printer, no wheels.  Can't do anything until those points are rectified at minimum.

[bbussey]

I discovered belatedly that the Thrall circus flatcars had ratchet brakes, after I had constructed my three models with brakewheels. At first, I was going to let it go, since the bodies are painted and detailed already. But then I remembered I have a digital ratchet brake for the upcoming G26 variations, which is based on the ratchet brake used on the BLMA 52’ gondola model. So I prepped them and printed a tray full. They are tiny but they did render.



This is to check how they looked on the model. The Ajax brakebox and brakewheel were subsequently removed, as was the fulcrum and bottom two links on the ratchet brake. The ratchets were epoxied in place. The area will be hand-painted tonight.



The parts were so small that I put them in capsules to cure them. I didn’t want to leave them on the runner in case it would be more difficult to remove them. Pre-curing, they easily snapped off.



Prior to that, I had put them in a paper towel and blue-taped the edges to seal before putting in the sonic cleaner.  I had snapped off maybe ten pieces from their runners while removing them from the printing plate. The sonic cleaner dislodged the blue tape! Fortunately the paper towel stayed folded over so all of the loose parts were still inside.

[timwatson]

Nicely done on that chain! I printed some ho scale turnbuckles recently. It was pretty satisfying. Much like your results are.
I’d love to see the cad of the chain. That’s geeky goodness to me.

[Lemosteam]

Would be interesting to see that printed vertically with the box at the boiled plate. You might achieve holes in the chain if they are there in CAD, and you would not need supports under the chain.

[PJPickard]

RE the magnetic build plate that has come up in this thread and in another one...I asked about these awhile back and the response was ummm not so great:

https://www.therailwire.net/forum/index.php?topic=51437.msg698247#msg698247