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View Full Version : Is Evergreen styrene machineable?



Lee in Texas
08-19-09, 09:15 PM
I want to make a blower housing in 1/8 and I'm short on raw materials. Can I laminate some thick Evergreen and machine that?

Rick
08-19-09, 10:11 PM
Lee, hopefully Jeff will pick up on this. He's done some incredible scratchbuilding with styrene.

Take it away Jeff...............

hot ford coupe
08-20-09, 02:46 AM
I gotcha Rick.

Hey Lee. If you mean can you laminate thick styrene sheets and carve them into a particular part, the answer is absolutely yes. The thickest styrene I've been able to find is 3mm thick. Anything greater than that, I laminate the sheets with plenty of liquid glue and then put the pieces in a vise and squeeze until I can't squeeze it any more. I leave the stock in the vise for about 15-30 minutes and let it set completely overnight. If I want thicker parts, I'll laminate 2 pieces with loads of liquid, stick it in a vise and squeeze, take it out of the vise, laminate another sheet, stick it back in the vise and repeat as many times as I need to get the full thickness of my part and then some so I have something to carve down. Below are some pictures of some of the things I've made the way I just described.

http://www.scalemotorcars.com/forum/images/imported/2006/08/7.jpg
The bell housing alone is made of 5 laminated 3mm sheets and then carved.

http://www.scalemotorcars.com/forum/images/imported/2009/04/95.jpg
The head is made of 3 laminated sheets carved down and the timing chain cover is 2 laminated sheets and carved down. Hope this helps. If you have more questions, let me know.

Here's what's under the valve cover.

http://www.scalemotorcars.com/forum/images/imported/2009/04/96.jpg

Unfortunately, this engine fell off a shelf and that was that.

gbritnell
08-20-09, 09:13 AM
Hi Lee, just to add to what was already stated, yes you can laminate and machine styrene. I realize this is at the other end of the spectrum as far as large scale goes but I have built several variations of Revell's old 1/48th pickup trucks. These were almost complete remakes of everything but the bodies. On this one I laminated 1/8 sheet styrene and milled the block out. You can see the joint line where the pieces were glued together. I'll just post a couple of pictures as I don't want to totally hijack this thread.
gbritnell

Lee in Texas
08-20-09, 09:17 AM
Thanks. It's been a while since I've machined anything. The supercharger is a roots type, with a case that is half round on each side, like this:

http://www.scalemotorcars.com/forum/images/imported/2009/08/97.jpg

Since I don't have a half-round cutting tool big enough, I decided to make two big pieces of half-round styrene. I laminated some .100" Evergreen with liquid cement, but used a few drops of CA for the middle. After it is turned on the lathe to a cylinder shape, and gets the fins/ribs cut, I'll pry the two halves apart with a razor, clean up the remaining CA, then glue styrene in between them.

BTW this is for a TDR Offenhauser. I have a book with several photos of Supercharged Offys, a couple by Miller/Drake and a couple of privateer drag cars.

Lee in Texas
08-20-09, 09:24 AM
Hi Lee, just to add to what was already stated, yes you can laminate and machine styrene. I realize this is at the other end of the spectrum as far as large scale goes but I have built several variations of Revell's old 1/48th pickup trucks. These were almost complete remakes of everything but the bodies. On this one I laminated 1/8 sheet styrene and milled the block out. You can see the joint line where the pieces were glued together. I'll just post a couple of pictures as I don't want to totally hijack this thread.
gbritnell

THAT is really cool. Size is irrelevant, it's still machining laminated styrene.

I've been away from modeling for too long. It's good to get some bench time and get the little machines fired up again. I'm really excited about the Offy project.

Lee in Texas
08-20-09, 09:25 AM
Jeff-
What is the block made of on that Olds?

edit: In the "Similar Threds" link at the bottom of the page, I saw a couple of your tutorials on styrene. There was some discussion on different liquid cements. I have used Testors in the past, but got some Weld-On 3 on the advice of another builder. I like that stuff a lot better.

hot ford coupe
08-20-09, 01:08 PM
Hey Lee. The block is also styrene. Its basically the 3mm or 1/8 inch thick styrene measured and cut, then glued together. The surface texture is also styrene strips and pieces glued right to the slabs. Originally I was doing a tutorial on the engine and where you see it end is where the piece took its fatal dive off the shelf. I'll probably go back and start a new one in the future and hopefully not lose it to gravity.

http://www.scalemotorcars.com/forum/building-tutorials/1293-scratch-building-1-8-scale-engine.html

http://www.scalemotorcars.com/forum/building-tutorials/1464-continuation-scratchbuilt-olds-rocket.html

Here are the two threads I did. If you need more info, just let me know.1yeah1

Lee in Texas
08-22-09, 01:29 PM
Another question: with enough curing time, will the glued-up block ever look like one solid piece when machined, as opposed to having soft spots where the joints are?

hot ford coupe
08-22-09, 03:48 PM
Absolutely, Lee. The trick is all in the vise and the amount of liquid glue you use. I make sure I have a good amount of glue on the surface by brushing on a number of coats with a wide brush and then squeezing the heck out of the pieces. You should see the excess glue/plastic mix squeeze out of the joint all the way around. I leave the piece in the vise about 15 to 30 minutes but if you're really concerned, there's nothing wrong with letting it set under pressure overnight. I never had any real problem with soft spots. This is one time when rushing to get things done will jump up and bite you. If you do have a little defect, just add a little filler and sand it. You really shouldn't need much at all.

strevo
08-22-09, 04:06 PM
Lee,
When I built my surfboard, I made the tail fin by laminating several pieces of styrene together with Tenax glue. Once it was dry (overnight) it was like one solid piece that I could sand and trim with no soft spots.
-Steve

Lee in Texas
08-22-09, 09:30 PM
Thanks, Jeff. I have a chunk glued up that was going to be an Offenhauser block, but then I found out about TDR's kit. That was glued with Testor's, but then I found out about Weld-On 3. I may glue up some big chunks for future use, just to have it on hand. I like being able to glue it rather than using screws or solder.

hot ford coupe
08-22-09, 11:08 PM
No problem, Lee. You should love that Weld On 3. That stuff is way better than the Testor's glue. Now I realize why you were talking about soft spots. I tried the Testor's glue once and wound up with problems. I use Plastruct because my LHS can't get the Weld On. It's just about as good as Weld On.Tenax will also work pretty good. Throw away the Testor's. P';,[p I did.

Lee in Texas
07-29-10, 03:46 AM
I had forgotten about this thread. The blower housing didn't work out too well so the idea was forgotten about. I recently had an idea for another project so I tried laminating plastic again. This time it's a chunk 10 layers thick! I used Weld-On 3. I kept poking at the little globs that squished out to see when they would harden. I guess it's been about 10 days now. I just cleaned up 2 sides on the mill and it looks great. I was really concerned about soft spots and bubbles, but again, it looks great. I'd give it a 9.5 out of 10. A coat of primer and a little sanding and no one would ever know it was once sheet plastic. This is nifty.

hot ford coupe
07-29-10, 10:06 AM
If you're really squeezing those sheets together with plenty of glue, you should have no problem. You will see a few bubbles here and there but they'll all be incredibly minor.

Richard Bartrop
12-21-13, 02:49 PM
Something I've come across is that when I've glued a lot of styrene sheets together is that over time, the block shrinks, We are talking about years, but if you're going to put all this work into a model, you want it to last. Mind you, i didn't squeeze the block in a vice as you mentioned. Have you had anything like this happen to you?

Bugatti Fan
05-25-19, 12:15 PM
The original question about is styrene machinable? Most of the posts seem to have described fabrication methods rather than machining.
Yes it can be machined, but bear in mind the heat generated by drills, milling and lathe tools can actually melt the plastic.
So slower speeds and lighter cuts should be the order of the day when using machines on styrene, especially if attempting to drill out plastic rod on a lathe. The plastic is liable to melt onto the drill bit.

Bugatti Fan
07-08-19, 09:52 AM
Further to my last post a thought. If a potentiometer could be used between the mains electricity socket and the machine, this would enable variation to the machine speed for slowing it down for plastics machining independent of the machine's own gearing.