Plexi Secrets

[Fuganater]

So I'm looking for tips, secrets and general advice on a few things pelxi. I have one of those scrapper things so you can leave that out. I can Google till my fingers bleed but I want to know what are other modders are using.

What type of polish are people using? I've heard car polish works good.

What type of adhesive do you use? Do you recommend certain ones?I heard Weld-ON is a good brand.

Any tips for gluing pieces together?

+rep for the help! Links help too because I can't just go out and buy this stuff at Lowes/Home Depot. I have to order it online.

I appreciate y'alls help!!

[diluzio91]

well. for intricate cuts its easier to "melt" the plexi with a dremel and use the scraper to remove the crust, in my experience

[blueonblack]

I did a tutorial on edge polishing here (http://www.thebestcasescenario.com/forum/showthread.php?t=14390). When I made Onyx (http://www.thebestcasescenario.com/forum/showthread.php?t=14476) I found that best way to make straight cuts was a carbide-tipped blade on a table saw, and for curves and smaller cuts I used a Rotozip spiral bit in a router on a router rable. Carbide router bits on a router table are amazing plexi tools.

I bought the plexi for that project at a local plastics shop and what I needed to order I got from estreetplastics.com (http://www.estreetplastics.com/). They are a little high on their shipping but their product was top notch.

Also, cast acrylic is a lot easier to work with then extruded. There is a difference. It's more expensive, but it's denser, sands easier and has a much higher melting point, making working with power tools a lot easier. It will even hold threads for bolts and screws.

Edit: Polish - I used Mothers chrome polish on wet-dry sandpaper then jeweler's rouge and a buffing wheel.

Glue - WeldOn #16 is awesome. If you get good contact once it's fully cured the two pieces are literally one piece of plexi.

[mDust]

I've never polished acrylic before but I'd assume any automotive polish would work. Just test the polish in question on a scrap piece first to make sure there are no undesired effects such as hazing. They do make plastic polish though. I'd assume it works as good if not better. If you have auto polish laying around, try it.

I've used Weldon #3 with a relatively large syringe to weld straight cuts into a mostly invisible seam. Most of the Weldon products are not glue at all. They are simply a solvent that chemically melts the two pieces and then evaporates out leaving one whole piece. The welds I made were much stronger than the sheet itself and the pieces were impossible to separate at the weld. Every time I tried to pry them apart one of the sheets would snap under stress before the welded seam did. Tips on gluing depends 100% on what product you use. The only thing I would think would be a good general tip is to scrape all the edges as flat and perfect as you can to minimize air bubbles.

I've also purchased black and clear acrylic of various sizes and thicknesses from estreetplastic.com. I didn't think their shipping was very high, but I ordered quite a bit. The shipping charge probably increases more with sheet size than with sheet count. If you order a bit from them it usually turns out to be waaaaay cheaper than anywhere else I've seen as they have decent quantity discounts.

Cutting tip: the very easiest way to cut it depending on thickness is either a table saw with as high a TPI as you can find (generally metal/plastic cutting blades) or, for intricate cuts, a jigsaw/scrollsaw with a slow speed and the highest TPI you can find. I tried to brute force through a 1/4 or 3/8 sheet with a jigsaw with a normal wood blade and it ended up chipping the surfaces on both sides and melting through until the saw started to slow due to melted plastic all over it. The friction apparently wasn't enough to keep the plastic molten and it instantly cooled around the blade. The saw didn't care and hopped a couple times until the blade broke off. There wasn't any way to get the blade out without ruining the piece, so it was chucked in the scrap pile. I highly recommend to avoid melting as it's possible to get tools or blades stuck in the plastic and it leaves a terrible finish that would take a lot more finishing work to prepare for a decent weld-seam...I suppose colored acrylic would take less work as you can't see the interior of the seam.

[Fuganater]

I did a tutorial on edge polishing here (http://www.thebestcasescenario.com/forum/showthread.php?t=14390). When I made Onyx (http://www.thebestcasescenario.com/forum/showthread.php?t=14476) I found that best way to make straight cuts was a carbide-tipped blade on a table saw, and for curves and smaller cuts I used a Rotozip spiral bit in a router on a router rable. Carbide router bits on a router table are amazing plexi tools.

I bought the plexi for that project at a local plastics shop and what I needed to order I got from estreetplastics.com (http://www.estreetplastics.com/). They are a little high on their shipping but their product was top notch.

Also, cast acrylic is a lot easier to work with then extruded. There is a difference. It's more expensive, but it's denser, sands easier and has a much higher melting point, making working with power tools a lot easier. It will even hold threads for bolts and screws.

Edit: Polish - I used Mothers chrome polish on wet-dry sandpaper then jeweler's rouge and a buffing wheel.

Glue - WeldOn #16 is awesome. If you get good contact once it's fully cured the two pieces are literally one piece of plexi.


I've never polished acrylic before but I'd assume any automotive polish would work. Just test the polish in question on a scrap piece first to make sure there are no undesired effects such as hazing. They do make plastic polish though. I'd assume it works as good if not better. If you have auto polish laying around, try it.

I've used Weldon #3 with a relatively large syringe to weld straight cuts into a mostly invisible seam. Most of the Weldon products are not glue at all. They are simply a solvent that chemically melts the two pieces and then evaporates out leaving one whole piece. The welds I made were much stronger than the sheet itself and the pieces were impossible to separate at the weld. Every time I tried to pry them apart one of the sheets would snap under stress before the welded seam did. Tips on gluing depends 100% on what product you use. The only thing I would think would be a good general tip is to scrape all the edges as flat and perfect as you can to minimize air bubbles.

I've also purchased black and clear acrylic of various sizes and thicknesses from estreetplastic.com. I didn't think their shipping was very high, but I ordered quite a bit. The shipping charge probably increases more with sheet size than with sheet count. If you order a bit from them it usually turns out to be waaaaay cheaper than anywhere else I've seen as they have decent quantity discounts.

Thanks guys. Cutting is not an issue. Just trying to see what people are doing for gluing and polishing. I think I'll play with rounding some edges tonight and polish them once I find some. I'll probably have to wet sand the edges that you can see and then polish it to give it a nice look.

Thanks for all that have replied so far! Keep the ideas coming.

[blaze15301]

Most of the time when I have a piece of plexi I need to glue i just get some super glue. Works just as well as the other stuff. As for cutting the plexi i bought a scroll saw so i could make clean cuts. if you cant find one of those, use a jig saw with a plexi blade on a low setting. Not to slow tho or you will just crack it.

[slaveofconvention]

I use brasso for polishing plexi (Brass polish), but I really want to try Farecla G3 and G10 cutting and finishing compounds and see how they work - in fact, I might do that this weekend assuming my compressor quits smoking :s

[Kayin]

I flame polish. Simple, fast and effective.

[Fuganater]

I flame polish. Simple, fast and effective.

Thats less than helpful lol.

[TheMainMan]

What he's saying is that he uses a flame to polish the edges by heating them until the just barely melt and the plastic edge winds up with a polished, glassy edge. There are many tutorials out there on how to do it.

[diluzio91]

if you do flame polish though, be sure you practice a lot first, its very easy to have your plexi bubble

[mDust]

Flame polishing works very well with practice, but don't do it to edges that are to be solvent welded. The resulting bond will be weak.

[Fuganater]

Ok I might have to try it out and see what happens. I just started playing with bending plexi and so far its worked out great. Might do a few pieces for the inside of Honeycomb.

Thanks all for your info.

[Kayin]

Sorry, I thought you had run across the concept of flame polishing before. I should have been lees abstruse.

[CorsePerVita]

I like plexi but I prefer lexan if possible since polishing it tends to take a bit better. It's a lot harder, and you'll spend a few extra dollars but the stuff is much harder and less prone to scratching as much as plexi. If I polish plexi though I will use something non-abrasive if I can, meguiars plastic polish tends to work really well. There was a 3 step plastic polish that was made I used but I had a hell of a time finding it so I stopped using, I'll see if I can hunt down one of the bottles in my garage, it was a 3 step, but it was freaking amazing on plexi/lexan and generic plastic.

[Kayin]

You're thinking of Novus polish. Dunno where it went.

[CorsePerVita]

You're thinking of Novus polish. Dunno where it went.

YES! THAT is the name I was looking for. That stuff was amazing! I seriously cannot find it unless I look for it online. The local store I used to get it at stopped carrying it, no idea why, such a quality product :(