Joe,these are just fantastic!My hats off to you sir! Now,will you be entertaining the idea of building these in N scale?If so I'll place an order for 200 right now.
You Old School Model building guys are doing a fantastic job with your Molds. I know Tim is also a Master and I'm proud to have a stunning Mi-Jack from him. Joe, it would be interesting if you plan to make a few of this Cars for Trade.
Well, here's a good photo of a similar looking car that just happened to be featured in the Railfan Photos of the Week:
trade Hi Jurg, Thanks for the kind words. Trade is the name of the game! I would be honored to have some of these running on your layout no matter what the deal. I work for MTL so I cannot go into production of course and have no intention of getting back into that game (produced resin ship models for 15 years) so the idea of making a few, giving them away and having them spread around the world feels good. If it gets more folks interested in Z then we've all benifited. I still do ship and architectural models on the side as well as sculpting for Disney, so the thought of having to fill hundreds of orders is too much now. I hope to do a string of 15-20 of my own and am saving for an AZL SD45 to lash up with my GP-35's to pull them. Once I get the four molds made I will be able to get a number of extras poured and send them out to those who would like a few. Maybe it will inspire others to take up the challenge like Robert Ray and others and provide more kits for us all. Thanks again. Joe
N Scale I doubt I could convince MTL to do this prototype since very few roads actually used these...(SP) There are near sisters but not near enough....too much "fudge" to toss around. I plan on doing these in Resin once I get these done in Z. I have 3 SD40-2's that I don't run anymore, would like to weather them up and put a string of theses behind them for a display on my shelf at home. I think if they were messed up enough it would be a striking diorama. I also have an old model of the 20 Mule Team that hauld Boax and other minerals out of the same region, it would be fun to cobble something up like that in N Scale and have that mounted near the track... Just need more time. When I get around to doing this I'll post here and if you want a few castings, I'll see about sending them to you. Cheers Joe MTL
Here is the two halves of the mold. Letting it rest a bit this morning before I start pouring...stand by. Joe
Ok, so you must be a freelancer or something like that since you do stuff for Disney and MTL, lucky you! I've notice your little Piglet here, nice touch! I've tried sculpting, but it is not my main expertize, it is only a hobby that I need to practice. http://animeksmodels.blogspot.com/2006/07/tiny-astronaut-figure-step-final.html I would really like to see your other stuff, probably on a blog or something? Thanks for showing your work. Ben
Here are shots of the mold, the pour and the first item! Now the vents are really big on these, but since these are just the working castings to provide patterns, I can work around them. On the final object I'll vent using sprue lines in the lower half of the mold to a central vent on the lower end of the mold. Cheers Joe MTL
Joe, Wondering what brand/type resin you use? I had the stuff from Micro Mark (CR-600) Only about 50% of my casting were good. The resin would be very soft and sometimes would not cure the whole way (fun cleaning out the mold after that) I was mixing it good. I hated it and it goes bad in the bottle after a few months. I have some Alumilite now and it is great, but the working time is very small (like 2-3 min. and it's solid!) I will never buy the CR-600 again. I'd like something like Alumilite, but slower. I saw the Smooth On site, but not sure what I should try as they make many different types. Any input. Thanks
The only thing I know about resin... STIR, STIR, STIR, until you feel it getting warm, and don't whip air into it. If it don't get warm, don't pour it in your mold, it's not going to set correctly.:shade: I learned the hard way!mg:
Resin Howdy, I use Smooth On Smooth Cast 300 and I have a working time of about 3-4 minutes and a demold in 10. I beleve the 310 is a 7 minute set and a 20 minute demold. I used to mix the two together 50/50 to get something close to 5 minutes working time which seemed to work out best for my ship models. You can get it in pint sets and in z that goes a long way. I use Mold Max 30 for my RTV for 10 years with no problems at all. The key is to put the parts under pressure after you pour them...otherwise you will have bubbles and voids Hope this helps. Joe
You must just use the right kind off resin. I just wisp the two components for about 5sec. until the color is unified then just poor it in. The sooner the better, it's like water at first and it begins to harden after about 15-20sec. After about 20-40sec. the resin is to harden to poor in and in 1min. it's solid. After about 10min I can take it out off the mould. As long as you get the mixture close to 50-50 it cures right every time. You can sand it after about 20-30min. PS: Now I use another brand off resin. But it's almost the same stuff. Just a little whiter and a bit harder after curing.
Thanks, I will try the Smooth On next time I order resin http://www.smooth-on.com/default.htm I have had pretty good luck on the bubbles, but lets say I wanna go "all the way" What could I use at home to make a pressure pot? I have a compressor. What sorts of psi's are we talking here? Maybe this will be new to someone: I use LEGO's to make the box for pouring the mold.
Go to Home Depot and get a 1 gallon pressure can for spray painting. I don't know how much they are now, but I have a 1 Gallon a 5 Gallon and a 15x24 Autoclave converted into a pressure pot. Only run it up to 40psi when casting for safety...you can go more, but I would check with the mfg first. Joe
Here is one of the castings with the couplers and the trucks mounted. I put a few grams of weight in it and it tracks as advertized.. Now on to the brass and stressing the surface of the castings... Joe
Thank you very much Joe,either way,I'd be very interested in buying 200 or just a couple in N,look forward to it
I'm with Joe on the Smooth-Cast 300 series. I've used all of the products in that family, I think. The only one that I didn't really like ( I ordered it by accident) was the 300Q. It only has a 30 second pot life and cures in 4-5 minutes, it also cooks the hell out of the molds, and has fairly large shrinkage. I use the 300 (3 min pot/10 minute cure) for a lot of things, especially if I am planning on making a lot of small pieces at once. The 305 (7min pot/30 min cure) I use for larger pieces. I use the 310 (15 min pot/2hr cure) for making additional masters. It has very low shrinkage. If you plan on doing any drilling/machining to your cast copies, shrinkage can make a huge difference. I had to trash about 30 stand-pipe bases because I didn't check the shrinkage rates of the faster curing resin. I would probably suggest the 305 as a good general purpose resin. It is easy to work with, has a 7 minute pot life, and a reasonable cure time (30 minutes). Shelf life with this type of thing is always an issue, but the Smooth-On stuff is available in small enough containers that if you plan your pours, the waste can be minimized. Important safety tip: never let any amount of water get in with the resin (or in the mold), it causes a foaming effect. Even a drop of sweat in a mold can render the part useless. For open (one sided) molds, I have also had good luck with their OOMOO series silicone rubber. It is a bit too soft for two sided molds, though. Dan S.
Dan, I used that 300Q to do progressive shrinkage on some parts once. I think I was clocking something like 4% reduction in size each pass. I took the rest of the batch and we poured it together and dropped it into an empty metal trash can...smoke big time.. They also have a fast cast clear now and for folks who are doing open face molds and don't have a way to pull pressure, you can pick out the bubbles and get some pretty clean casts. You can spray the surface with a little mold release and it will break the surface tension and get rid of any bubbles on top....back to etching.. JOe
