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Planning Anybody use REAL Lexan?

Discussion in 'Modding' started by jhanlon303, 3 Mar 2009.

  1. jhanlon303

    jhanlon303 The Keeper of History

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    I was at one of the Habitat for Humanity thrift stores today and the had a very large stack of "scratch resistant" Lexan panels in 2' x 4' x 1/4" thick.

    I have a small piece of real Lexan that is about 5" x 7" and came from a windshield of a Strike Eagle jet. DOD souvenir.

    My question is what means scratch resistant and can it be worked for what we do?

    john
     
  2. Cheapskate

    Cheapskate Insane? or just stupid?

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    My first scratch build was black lexan. It's pure hell to hand cut, but easy to cut with a table saw.
    I have some 1/2 I'm still debating on how to use.
    1/4" lexan is expensive. I'd jump on it if the price was right. It's very different from plexi. It's easier to plane it, rather than sand.
     
  3. jhanlon303

    jhanlon303 The Keeper of History

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    That's pretty much what I thought. My small sample from the windshield is bullet proof and shatter proof at 1/8".

    The sheets are $10 but I could build a SFF case out of 1 or 2 sheets.
    They have a bunch still in the original paper covering. The stack is as tall as me at 5' 10". They appear to have 2 small holes along the long side toward the top and bottom like maybe hinge placements? I think They might have been doors from some cabinet manufacturer. But what doors need to be shatterproof? Jewelry displays? Money launderers? Maybe something from the casino industry in Colorado?

    john
     
  4. ROB 636

    ROB 636 Ski-Ba-Bop-Ba-Dop-Bop

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    Gas station counter windows?
    [​IMG]
     
  5. Cheapskate

    Cheapskate Insane? or just stupid?

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    $10 for a 2' x 4' x1/4" sheet is an amazing steal. You can cut it with a jig saw too.

    I wonder about that bulletproof 1/8" bit you are talking about. I'm pretty sure I can find something that could puncture it. -Hell, I could poke a hole in the 1 1/4" plexi sheet I have too. You have to be careful about using the B word.

    -The stuff's good for solariums and batting cages. Maybe this is from the cart that picks up balls at the driving range.
     
  6. ConKbot of Doom

    ConKbot of Doom Minimodder

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    Lexan is good stuff, its pretty much the closest thing to metal that Ive ever seen any plastic.
     
  7. Burnout21

    Burnout21 Mmmm biscuits

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    you need to find some PEEK (polyetheretherketone), then makes Lexan look silly.
     
  8. ConKbot of Doom

    ConKbot of Doom Minimodder

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    Ive handled some parts made from it, but I havent machined on it any.

    I guess lexan is the closest you'll get to transparent aluminum :)
     
  9. barry99705

    barry99705 sudo rm -Rf /

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    Funny, the canopy on the F-15E is thicker than 1/8 inch. More like a half inch and it's not bullet proof. Now the front windscreen is bullet resistant up to a 20mm round, but it's several inches thick.
     
  10. undertheradar

    undertheradar What's a Dremel?

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    I do acrylic fabbing... usually do aquariums and reef aquarium equipment... bonding with weld-on, heat bending/forming (cones, domes, etc).

    Scratch and AR type lexan is usually just very hard to bond/dissolve with weldon (the usual glue for acrylic). It just resists scratching more, as acrylic/lexan is usually easy to mar/scratch. As long as you just plan on cutting/drilling/etc... it means nothing really.

    As for things that are better... well... most bullet-proof plexi is a laminate... varying in total thickness from about 5/8" (stops small .22's and such) up to 2" or 3" thick (shotgun/.50 cal). There are different means of making the acrylic (or glass for that matter) more resistant/stronger, depending on what the problem is. Hurricane glass, for instance, is very thin, but made with multiple thin layers of glass and plexi. You can stand on a 3x3 skylight with this and drop a bowling ball on it and it will bounce. Its got alot of 'impact' resistance... bats, crowbars, bowling balls, and 8 foot 2x4's going 200+ mph in a twister. If you shoot it with a small bullet though, it will shatter. There are different applications of lamination and thickness depending on what you intend as far as impact and penetration. The designers of the F-xx (if thats what its really from), might have figured if a 20mm bullet makes it that close, its too late, but having a 'gummy' lexan that can take blunt impacts like from birds, shrapnel, etc... could prove life saving. If you have a 20mm bullet coming your way... I dont think there are many canopy materials that can take care of that. A barrett .50 cal rifle is designed to stop vehicles by shooting the engine block... 20mm would require something like 4-5" thick lexan to stop it... not gonna happen.

    There are 'other' materials though... clear aluminum is going through military testing right now.

    I doubt its bullet proof of any sort, and when I saw the bubble on a F16 it looked a good inch thick... most likely some cast laminate. If its only 1/8" thick... its not bullet proof though... not unless it bends like a rubber band to absorb the impact energy.
     
  11. Cheapskate

    Cheapskate Insane? or just stupid?

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    I've hit a duck doing 50mph. I don't even want to think about what would happen at mach 2.5.
    -I'm thinking the stuff's from a hockey rink.:D
     
  12. barry99705

    barry99705 sudo rm -Rf /

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    It stinks, though we hit a seagull. I've also had to clean up after a sparrow hit a Lantern pod. Bats just leave a bloody streak, not enough mass to make much of a dent, that and at that altitude the jet's not going that fast.

    You should see what a caribou does to a French cargo plane!
     
  13. jhanlon303

    jhanlon303 The Keeper of History

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    Or a full grown pregnant sow does to the front end of a 1970 Chevelle SS.

    We had to pay for the sow too!

    john the backseat passenger
     
  14. Cheapskate

    Cheapskate Insane? or just stupid?

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    Flying caribou? That alone is a scary thought!
    I've seen the results of a chance meeting between a cow and a minivan. The cow won.
    Next question: Which one of you lurkers swooped in and bought all the lexan before John could?
     
  15. cpemma

    cpemma Ecky thump

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    I've used it in 1/4" to make a Hull Cell, where acrylic didn't have the temperature resistance for near-boiling liquids. It's also commonly used for machine guards, such as on drill presses, safety visors and riot shields.
     
  16. barry99705

    barry99705 sudo rm -Rf /

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    Naa, they were doing illegal touch and go's on a dirt runway. Rudolph walked out in front of them. My cousin was in a coma after he and his buddy took out a cow in their S-10. Crushed his skull, didn't think he was going to survive. He's okayish now, though it did mess with him a bit. He'll tell you exactly what he's thinking, good or bad. I've also seen what's left of a grand-am after it hits a bull moose at 95Mph. Sheared off everything above the hood. Was not a pretty sight.
     
  17. C-Sniper

    C-Sniper Stop Trolling this space Ądmins!

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    One of the guys at the airport had an unfortunate event with a Beech KingAir vs. a Deer. This was on landing at a nearby airport that doesn't have any fencing what so ever. Aircraft was a near write-off and Bambi was shredded by his #2 prop.
     

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