Anyone work with clear Polycarbonate or Acrylic sheet?

[Doc Tinker]

Tell me the difference between Polycarbonate and Acrylic . What is easier to work with? How do you cut these products into odd shapes and obtain a finished edge? Where does a guy buy either of these products?



Doc

 

[Briar Hopper]

I'm not a big fan of acrylic. It breaks. I prefer polycarbonate. My uncle used to get big sheets of it from Rohm-Haas, a brand name called Tuffak, (cheaper than GE Lexan) so we could form spoilers and other items for the race car. It's bendable to a point, in a sheet-metal press brake. Best way to cut it is with a jigsaw.

It can be obtained from McMaster-Carr Supply Co. , Cleveland, OH (330) 995-5500 www.mcmaster.com

Some hardware stores do carry it, though usually not in pieces bigger than 3 feet.

 

[LSMITH]

I agree with Briar that the poly is way tougher, but acrylic is harder to scratch. Poly will flex quite a bit, acrylic will not flex much before it breaks. The tougher poly is easier to work with.

I have used a circular saw to cut it as well, the secret is a brand new carbide blade. A router is the best way I have found for complicated shapes, but again the bit must be new and perfect. With the router you want to feed the material pretty aggressively, or you will be rubbing the material with the bit and it will melt. If it melts the game is over, so keep the bit cool with fresh material to cut. You can use a round-over type bit to clean the edge up, or you can just sand the sharp edge off. The easy and best way to finish the edge is with a router, just feed it aggressively. Drill all inside corners that are not routed to a radius to keep them round, a radius is necessary to prevent breakage. I would suggest that you lay out your project and practice with the waste material to get a feel for it before tackling the meat of the job. It does take a bit of feel to do it without breaking it.



If the project you have in mind can be opaque Delrin is 100 times easier to work with and more durable yet.



The big chain in the upper midwest is Cadillac Plastics, I think there is one near you Doc. You can order from them over the web too. Hope this helps.

 

[illflem]

I got to work with Lexan for the first and only time last fall when a rock thrown from a tractor mounted mower went though the side of our greenhouse. I found it very easy to work with even though I needed a 6'x 32 foot sheet, the roof and wall were one piece. Made the 60° bend very easily and cut with a fine blade on a saber saw. The stuff I used was double wall with an air space and extremely expensive.

 

['956Wheel]

Polycarbonate is tougher but not as hard as Acrylic, Polycarbonate is easier to drill, mill, saw etc. without the fear of cracking. Also Polycarbonate is more "optically true" (very little distortion). We used it as spinners in front of video cameras to avoid water hitting the lens when doing whitewater footage, you spin it with a motor to keep the water off.



Mike

 

[LoneRam]

What did you have in mind

Doc, where are you going with this? I know my plans couldn't have reached you yet. I have been looking into the same products for a valve cover. Shouldn't be too much $$ and it sure would be cool I guess after many, many miles things might start to look ugly, but until then when you lift your hood, :--) Just wouldn't look the same on a V-8 Well, if anyone is interested and I do come up with a source, the shipping from out here might not make it worth it, but it is only money and that's we go to work.



LoneRam

 

[Briar Hopper]

Why do we need a see-through valve cover? As much as I love that engine under my hood, it's still just oil covered valves under there, not a set of 36 D's... .

Victoria's Secret Valve Covers?

 

[LoneRam]

Just the way I am

I guess I am just sick in the head. I realize that when it's running there will be nothing to look at, but owning a truck like this has nothing to do with basic needs, it's about exploring our god giving rights as men(women are invited too, sometimes) to have loud, powerful, snarling beasts parked in our driveway. To hook up to whatever we want and move it. To grunt and scratch and beat our chests with pride at our very existince. We have forged earth into this magnificent creature that lives beneath our hood and it is only fitting that we should display it in all it's glory every oppertunity. Besides, I just got divorced and have no use for Victoria's Secret, she can keep it for now.



LoneRam

 

[ZEEEW]

I have used both for critter cages. Acrylic was too breakable, the iguana would get in his moods and simply bash through, wasnt flexible or tough enough. I scored some polycarbonate for the snakes, was easier to cut and drill without breaking or cracking. I used a circular saw with good results, did a cleanup on the edges with a file.

Safety glasses are frequently made from polycarbonate.



Eric

 

[Doc Tinker]

I've read that acrylic is a good sound barrier. Maybe a valve cover made of the stuff would reduce noise. What about heating a sheet in a big oven and then forming it to the floor of the truck, under the carpet of coarse, for a large noise blocker?



I know... Briar won't understand the quest for less noise



Doc

 

[JWhitcomb]

A valve cover? Are we talking a one piece or one made from five or so pieces? If you are screwing it together I would think it needs to be thick and use heli-coils plus the joining surfaces sealed. Vibration will affect it so use locking heli-coils. Not too long ago I did a job out of thick opticaly clear and the idea of a one piece cover came up. I would have needed backing from Ft. Knox to finance the blank stock.

 

[fest3er]

My brother is a co-owner of a plastics company in NE IL. He will gladly sell you whatever you want. Email me for his contact info. Send him a print and he'll fabricate it, too. But they don't do much with forming - only bending and gluing, no complex 3D shapes.



The *best* way to finish a cut edge is to use a blowtorch and momentarily heat it. The flame melts the 'light scattering' imperfections and leaves a 'polished' surface. But use care. Too much heat will 'brown' the plastic.



To form the plastic to the floor pan, you might need a good heater above the plastic and heat it only long enough for it to bend. Too much heat and it will deform. Hmmm. How about using expanding foam to create a 'mold' of the floor pan, and doing the forming inside a shop?



Has anyone tried Herculiner on the valve covers? I would suspect the extra mass would dampen noise emanating from there.



Fester