# Ps2cd4427



## Burl (Jan 2, 2008)




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## Burl (Jan 2, 2008)




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## Scott (Jan 29, 2008)

Burl, once again you show your awesome talent. It's a beauty.


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## Burl (Jan 2, 2008)

I'm posting some more photos before I weather it.

Some pre-paint photos:














































An out-take from the "builder's photo" shoot:


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## East Broad Top (Dec 29, 2007)

Nice! The only "giveaway" in the black-and-white photos is the wheels. (A necessary evil, I know.) But even then, I had to do a double-take because everything else looked so great. 

Later,

K


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## Scottychaos (Jan 2, 2008)

wow! that's fantastic..
I really like the intentional slight warping of the "sheetmetal" sides!
(I know its plastic on the model..metal on the prototype)
few modelers would bother with that detail..that really dramatically increases the realism..
brilliant! 
Scot


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## TrotFox (Feb 15, 2008)

Personally, I'm amazed at how well the accurate modeling hides the Kadee couplers! =D The warping of the panels provides an excellent effect that puts the model firmly in to the "realistic" category. =D

Trot, the impressed, fox...


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## Burl (Jan 2, 2008)

Here are all the major resin components (except AB parts). I have tried to make this as easy to assemble as possible.


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## East Broad Top (Dec 29, 2007)

Is the main carbody open inside? Seems it would (a) be very heavy if not, and (b) eat up an inordinate amount of expensive resin. 

Later,

K


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## Burl (Jan 2, 2008)

Yes, its hollow.


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## Burl (Jan 2, 2008)

This is the rotational casting machine I built. I started out with cordless rotisserie motors, but they couldn’t handle the load and began to fail. I upgraded to gearmotors (from McMaster-Carr). The primary motor is AC. The secondary is DC, driven by rechargeable AA batteries.



I also started out with pipe flanges on everything, but the one on the primary axis failed due to the stress. I ended up having a bracket fabricated for it (the welder thought I was stamping grapes?).



This was like re-learning everything I knew about casting. It took a lot of experimentation, and 2 or 3 gallons of resin, to figure out how to reliably cast this mold. It takes 8 separate pours to get one body casting. You’d think you could dump all the resin in, turn it on, & have something finished in 20 minutes, but it pulls away from the mold and turns into one, big, messy glob in the middle. So the pours are small, and 15 minutes apart, to keep the heat from building up and making the resin kick too soon.



The rotational aspect is all new to me. I would say it took me 6 months or so of design & testing before I finally had something settled.



BTW, the mold you see took 3 gallons of RTV. There’s a top to it (not pictured) with two plugs cut into it. One plug is for a funnel (for the resin), the other is an air vent. I have about 20-30 seconds to get the resin in & get the mold buttoned up, or I get an uneven coating in the mold. I’d say I’m getting usable castings out of it 90% of the time now.


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## YBelanger (Jul 24, 2011)

Just outstanding! Congrats.


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## TrotFox (Feb 15, 2008)

That is some beautiful plywood engineering! 

Trot, the impressed, fox...


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## CliffyJ (Apr 29, 2009)

Burl, 

I've only seen rotamolding in the context of small (3-10') to huge (20-60 ft long) polyethylene / propylene casts, for plastic tanks & silos. Never occurred to me that there would be a modeling application. Great job, I hope you do a full article on this at some point.

Cliff


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## Burl (Jan 2, 2008)

I had been talking with Marc about doing an article from the beginning, but he finally decided to pass. His reason was, since that I intended to sell these as a kit, that it would be a conflict of interest for the magazine. Not sure what I'll do now... I have been thinking about publishing something myself through blurb.com.


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## bnsfconductor (Jan 3, 2008)

A kit huh... Humm I may have to start saving some money and not put off buying (as it did with some of your other kits)...


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## CliffyJ (Apr 29, 2009)

Sorry to hear about the turn-down on the article. You indeed have a lot invested in this project (e.g., McMaster gearmotors, all that design time...). So I hope you find a means of sharing your journey. 

Another question, and this is just out of curiosity. Since pre-heating the silicone mold can make the resin kick more quickly (for thin parts at least), would pre-chilling the silicone have the opposite effect, and extend your working time?


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## Burl (Jan 2, 2008)

Yes, according to Alumilite, you can chill one side of the resin (I forget which one). I don't have a fridge in the shop though, and I'm wary of storing resin near food, so I have never done it.


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## Burl (Jan 2, 2008)

Finally got my second set of parts from Shapeways:


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## CliffyJ (Apr 29, 2009)

Nice parts Burl!

I sure you knew that you don't need to make a sprue tree to hold them together for printing, right? If not, you can save some bucks, and just let them float in space. But, I expect you have a good reason for making the box. For one thing, it looks cool! And, it's obvious if something were to be missing.

Looking forward to seeing them go on your model. 

Cliff


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## DTI356 (Jan 3, 2008)

Those look really good Burl!

Brian


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## Burl (Jan 2, 2008)

Cliff: the parts are way too delicate to survive the printing process without the sprue. I went through 4 months of revisions with Shapeways before I finally got something that would print reliably. If I had my own SLS printer, then I could get away with leaving it off. But you have no control of what else is jammed in the print job with a 3rd party. And nylon is cheap anyway.

BTW, this is the last thing that was holding me up from offering kits for sale. The next thing to do is build another, and document it for instructions - then I'm in business.

On the pilot model, I drilled out the holes for wire grab irons - which was very tedious. On this revision, I printed the grab irons in place. So, I expect the 2nd one to be much easier to build.


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## CliffyJ (Apr 29, 2009)

10-4 Burl, I knew you had a good reason. Thanks for the back story.

For your kits, will you include cast parts, SLS parts, or a mix?


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## Burl (Jan 2, 2008)

You'll order the nylon parts from Shapeways (at my cost). Resin & decals, etc will come from me. I may have to bend that rule for international customers to save on shipping, but I'm not to that bridge yet.


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## Burl (Jan 2, 2008)

Since Shapeways revised their pricing algorithm, I thought I was dead in the water with this project. They upped the price for my nylon parts from about $100, to $300+. I have since been playing around with re-arranging them to get them back down to a reasonable cost. I didn't really like the idea of the ladders being a separate part, since the glue joint will be right on the corner of the extended part of the side sill, but I can't see any other way to do this right now. So I guess I'll be doing some experimentation with glues to see which is the best for this application. Anyway, I'll be breaking down two big parts into a couple dozen smaller assemblies. Hopefully it will still be relatively easy to put back together. Here's how I'm planning on having them printed:










The long grab irons will have to be separate parts, even though my rendering doesn't make it obvious. 
Here's an exploded view of what you'll have after the sprues are removed by the modeller:


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## Scott (Jan 29, 2008)

Yup, know this headache too well. Certain parts I've revised umpteen times. Gone back to original files, and rejigged this that and the other. Even enlarged parts - some items close to 1:20 to print and durability, but to fit onto model.

Almost like building a jigsaw in reverse.


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## CliffyJ (Apr 29, 2009)

Same here. It's one thing to design the model, and quite a second effort to package all the pieces to get to a reasonable cost. 

Before the Shapeways price hike, I didn't bother connecting all the pieces. Now that they put a per-piece adder, all my old stuff is way too expensive. So I'll have to revisit everything again and add the connectors & so forth.

Nice work Burl,
Cliff


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## harvey (Dec 30, 2008)

Nice to see the man behind the mask.
Cheers.


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## Burl (Jan 2, 2008)

I got my latest revision of printed nylon parts last week. I got around to seeing how they fit together today:











There's a couple things I need to revise in the drawing, but I think I almost have this finalized. 


I think I tried to do too much in this project. The 3d printing and the rotational casting were both new processes to me when I started this. I had a very high failure rate on the main body casting & I should have tried something simpler first (like a tank car). Even after I had enough resin parts made up for several kits, I found that some of the body castings had warped & were un-usable. All the good body castings were made with Alumite RC-3. (I experimented with several different brands.) I know some people have very different opinions than I do on Alumilite, but I have always found their resin to be very stable when cured.


Anyway, I said all that to get to this: this project has drug on for over two years, and I'm ready to put it away & move on. Once I take the mold box off the rotational casting machine, I probably won't put it back on. 

Now that the 3d parts are pretty much done, I can finish writing up instructions. I have resin parts for 4 kits made up that I am going to offer for sale. Cost will be $200 + shipping. They'll come with ATSF decals & photo-etched roofwalks. The SLS nylon parts will have to be ordered separately from Shapeways (around $115). You'll have to also buy trucks & couplers. 


I'm planning on offering my own trucks & couplers later, but I don't have a release date quite yet.


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## Burl (Jan 2, 2008)

I have one of these left to sell: http://burlrice.com/_LS_PS2CD4427/

It would normally be $200 for the resin parts, plus $120 for the 3d parts. However, in this case, I have all the 3d printed parts for it in hand, so the whole thing will cost $300. It is less trucks and couplers, but I can include Aristo-Craft trucks (ART 29100) and my own couplers for another $50.

If anyone is interested, please contact me through my website. Unfortunately I only have one, and it will go to the first taker.


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## josephunh (Mar 27, 2013)

Burl, I am curious where did you get your decals for that and what kind are they?


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## Burl (Jan 2, 2008)

They are ALPS decals that I print myself.


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## Burl (Jan 2, 2008)

I should have included this in the last post: the shopping cart on my website will not work for this model. Here is the link to contact me if you should want to order: http://burlrice.com/contact.php


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## Burl (Jan 2, 2008)

The shopping cart is fixed now.


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## Burl (Jan 2, 2008)

Brian Briggs’ wife, Margaret, contacted me about this kit today. As many of you know, Brian passed away a couple months ago. Margaret says she has two un-finished kits she would like to find new homes for. 

There is also a finished Union Pacific version she says she’s also willing to part with:










I told her I would post here on her behalf. If anyone is interested, please send me a PM and I will send you her email address. Or, if you have Brian's email address, you can use that to contact her.


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## Burl (Jan 2, 2008)

I should also mention, on the unfinished kits: Brian wanted to use his own laser-cut roofwalks, instead of the photoetched ones I was using, so these kits do not have my roofwalks. I still have the phototeched ones available.

Also, the kits he bought did not come with trucks & couplers.


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