Jump to content
Model Cars Magazine Forum

making resin engines


Recommended Posts

This is how I've been casting my engines. Block and all components are cast as individual pieces. Some are tougher to do than others! LOL If you have any questions, feel free to ask...

so this is the first time i have attempted to cast anything and i was knocking around the idea of casting a viper or Ferrari engine and modifying it into a 65 stepside pickup. looking at these engine/trans pieces i think it would make sense to do each half separate and try to cast them as they are off of the trees and then assemble the cast pieces. they look far to intricate to assemble and cast all together.

Link to comment
Share on other sites

Casting a complete engine would be a mess. Many, many opportunities for air pockets and bubbles, not to mention tearing up the molds getting the things out. I agree with casting the block as one piece....I've done many engine molds this way. Most of the rest of the pieces can be done as open face molds - the easiest kind to work with. Be sure to cover the mold after you pour your resin so you get a perfectly flat mating surface. Your problem areas, or the parts that will cost you the most time, will be things like belt/pulley assemblies, exhaust (if you include them) and small parts. The block, heads, intake, oil pan, etc, are all pretty simple.

I pulled molds and cast the entire 429 Ford from the Revell Torino a few years ago. I was pretty happy with the results, though some of the problem parts I mentioned above needed a good bit of cleanup.

429FORD.jpg

Link to comment
Share on other sites

If you do, feel free to ask me - and others - lots of questions along the way. I had a couple of great mentors when I was getting started and I can't overstate the value of shared experience. It's not hard to do, but it does cost some money up front to do it right, if you are at all picky about the results. It's really a lot of fun and if you are seriously into scratchbuilding (as I am) it's a must.

Link to comment
Share on other sites

I'm not much of a scratcher but but i do like to bash and mash lol. especially seats, steering wheels and engine parts. On the OP's subject of tips there's some debate about the 'starter kits'. Alan may have read about those also, what say you about starter resin kits.

Link to comment
Share on other sites

Casting a complete engine would be a mess. Many, many opportunities for air pockets and bubbles, not to mention tearing up the molds getting the things out. I agree with casting the block as one piece....I've done many engine molds this way. Most of the rest of the pieces can be done as open face molds - the easiest kind to work with. Be sure to cover the mold after you pour your resin so you get a perfectly flat mating surface. Your problem areas, or the parts that will cost you the most time, will be things like belt/pulley assemblies, exhaust (if you include them) and small parts. The block, heads, intake, oil pan, etc, are all pretty simple.

I pulled molds and cast the entire 429 Ford from the Revell Torino a few years ago. I was pretty happy with the results, though some of the problem parts I mentioned above needed a good bit of cleanup.

429FORD.jpg

so then in this instance i would cut the engine from the trans and assemble the engine halves and then cast the parts? it seems as if this is going to be a case by case basis. reading your advice, everyones advice, i can surmise that the intricacies of the viper engine would make it beneficial to do the engine halves right off of the tree as the trans and part of the differential and drive shaft are attached. is it better to do the engine halves in one mold and other pieces in separate molds or does that make a difference?

Link to comment
Share on other sites

I tried one when I was first starting out and all it did was cost me time and money. There's the right way to do it and then there are the easy and cheap ways. With the easy and cheap ways you generally get back what you invest. If you're just casting one part or a few parts, they may be a good solution, but if you are considering getting into it on any level above that, talk to some of the people who sell their resin and ask them how they operate. I really feel that you need a pressure tank and compressor, and you need to buy good quality silicone mold material and good resin. If there's an alternative I haven't seen it personally.

Link to comment
Share on other sites

I tried one when I was first starting out and all it did was cost me time and money. There's the right way to do it and then there are the easy and cheap ways. With the easy and cheap ways you generally get back what you invest. If you're just casting one part or a few parts, they may be a good solution, but if you are considering getting into it on any level above that, talk to some of the people who sell their resin and ask them how they operate. I really feel that you need a pressure tank and compressor, and you need to buy good quality silicone mold material and good resin. If there's an alternative I haven't seen it personally.

I went this way to see if i am really going to enjoy and actually do it. if so i will look into a more professional system

Link to comment
Share on other sites

so then in this instance i would cut the engine from the trans and assemble the engine halves and then cast the parts? it seems as if this is going to be a case by case basis. reading your advice, everyones advice, i can surmise that the intricacies of the viper engine would make it beneficial to do the engine halves right off of the tree as the trans and part of the differential and drive shaft are attached. is it better to do the engine halves in one mold and other pieces in separate molds or does that make a difference?

I've done it both ways. The main impetus for doing the 429 that way was that it came with a four-speed trans in the kit, and I wanted to build a replica of my racecar, which at the time had a C6 automatic. Casting the entire block/trans as one piece is problematic.....too many undercuts. If I was doing it, I would join the halves of the engine/trans and then separate the trans, but you'll probably have to have two kits to do that, because of the material you'll lose cutting them apart. You might well be able to add the missing material from thin sheet plastic. Casting the engine/trans halves works OK but if there is any warpage in your parts you end up with the two halves not matching exactly. That was my experience, anyway. Large lumps of resin like that can warp a bit and with something as long as the engine/trans, a little warpage can be a real problem.

Link to comment
Share on other sites

I went this way to see if i am really going to enjoy and actually do it. if so i will look into a more professional system

If you don't get the results you like, don't give up. I liken it to buying a cheap guitar to see if you like playing. Cheap guitars have ended countless guitar playing careers before they ever got off the ground.

Again, that's just my experience, and maybe the kits have gotten better since I got talked into trying one.

Link to comment
Share on other sites

so this is the first time i have attempted to cast anything and i was knocking around the idea of casting a viper or Ferrari engine and modifying it into a 65 stepside pickup.

If you are using an engine and it's related parts from a kit, then installing it without any major modification to the engine, it would be far easier and cost effective to simply purchase a donor Viper or Ferrari kit from which you can pirate the engine. Viper kits are a dime a dozen, cheap, and you'll spend $60+ just for the casting materials.

Link to comment
Share on other sites

If you are using an engine and it's related parts from a kit, then installing it without any major modification to the engine, it would be far easier and cost effective to simply purchase a donor Viper or Ferrari kit from which you can pirate the engine. Viper kits are a dime a dozen, cheap, and you'll spend $60+ just for the casting materials.

thats why i went to hobby lobby with the 40% off code got a starter kit for the same price as a model kit and i get to test if i am interested in resin casting. figured this is a 2 birds one stone situation.

Link to comment
Share on other sites

Well I tried my hand at resin casting last night and this morning and I have to say I think it came out pretty decent. I am going to need more silicon mold material but I think this resin viper engine will find its way into the 39 Chevy coupe that I am building in some form.

post-9427-0-61450200-1352657299_thumb.jp

Link to comment
Share on other sites

This is how I've been casting my engines. Block and all components are cast as individual pieces. Some are tougher to do than others! LOL If you have any questions, feel free to ask...

Is there any special prep to resin cast parts for painting? I.E. do I need to primer before painting or wash in any special way?

Link to comment
Share on other sites

Is there any special prep to resin cast parts for painting? I.E. do I need to primer before painting or wash in any special way?

It's always best to thoroughly wash each part that you cast and add a coat of primer before painting. Resins have an oil base to them that need to be washed away as well as any mold release chemical that may have been used.

Also, when it comes to breaking down the components for casting it's best to realize that the more pieces you try to cast as one unit will produce more undercuts for the resin to have to penetrate as well as considering how fragile the mold will be with all of those extra angles to access and as time goes by the mold will most likely start to break apart, especially in those small detailed areas.

Breaking down a complete engine in a format that would allow you to cast all parts as a one-piece mold works the best, in my opinion. However, some folks don't like all of the added assembly and lining up parts.

Link to comment
Share on other sites

The mold putty has its uses, but very limited.

I've used it for small simple bits like duffle bags, marker lights etc but wouldn't use it for anything complex. It doesn't really work well for two part molds, and it can leave a little lip around the edge on a one part mold if you do not get it mashed down over the part really well.

On the plus side it is really easy to set up and use when you want to make a quicky mold. I've only used it for simple parts of things I don't need a ton of duplicates of so the molds have lasted me for many years.

The one place it really shines is when you want to make a mold of something that is attached to another part. It works well for things like door handles, emblems on the hood or side trim etc. Understand that it is kind of tricky to make those kinds of molds well, and you will usually end up having to sand down some resin from the back of each casting, but there is no real way to use the usual liquid silicone mold material.

Edited by Aaronw
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...