cutting lexan....FRUSTRATION TIME!!!! argh!

[hulkster]

yep, i cut my lexan to size, no problem.  then i start drilling holes and its all melting and going out of place and my holes arent lining up with my wooden cp!  geez, this blows.  i really want to do something else besides this stupid lexan over the top.  i have contact paper and im debating just putting that down and using that.  will this be terrible?  

[AlanS17]

Contact paper will not stay down well. Lexan works well. I promise. What are you using to drill it? What type of bit are you using? (Please don't say a spade bit.)

[hulkster]

hmmm....sp--sp--spade bit  uh oh, i guess thats bad seeing that you say "please dont say spade bit"  yeah im using one, im guessing i should use something else, like a hole saw or something.  

[hyiu]

I cut and drill and saw lexan... and its ALL FINE !!!
 

Can you describe what exactly you do ??...
what kind of drill bits ??... what kind of equipment ??...

maybe you did something wrong.....

I've also heard people using router and also have good results.... well.... in short... you're the first I heard that has a rough time with lexan....

plexi is bad... but lexan is all good....

I did my first prototype stick using contact paper...
unless you're using metal panel, then you might have a little better luck.... if you're using wood panel, contact paper is not going to stick for long... it'll peel in all corners...

I would suggest try finding out what went wrong with your last drill.... test it with a scrap piece, and do it right....

my $0.02 cents....

[AlanS17]

A spade bit is a really bad idea because it will virtually melt the lexan on contact. That's what is causing the sloppy holes and the drifting. It basically liquifies the area around the hole and then your drill bit can move all over the place.

Try using a hole saw. Also make sure you're drilling in forward - not reverse. Some people recommend that for plexiglass to avoid cracking, but you don't need to worry about that with lexan. Just drill away.

If you MUST use a spade bit, try drilling without applying pressure. Let it scrape through a layer at a time. Pressure increases temperature and tempuratue increases melting.

[hyiu]

I use spade bit to drill thru. lexan and so far, did not cause any problem..... (and I have drilled MANY holes...)...

what I did first, is... I cut the wood.... and drilled the wood first, then I put the lexan on top (like how its suppose to go...)... after everything is correctly aligned..... I use clamps to hold them together.....  (ohh.... also, I usually will have like 2 screw holes on the edge to make sure it stays together... so, I'll also put on the screws and nuts also....

after making sure it's aligned and clamped / screwed together.... I flip it upside down....
so, now... the wood is on top and the lexan on bottom...
and I put the drill and the spade bit on the hole (so, it'll align itself.... and drill thru the lexan as if that piece of lexan is wood....)

hmmm..... I did not apply too much pressure... but I do apply some pressure.... (sorry... donno how to explain...) but as said... I drill thru it like wood....

I believe out of the maybe 30 holes or so that I drilled... maybe 1 or 2 will have a little roughed edge... (can be fixed by sand paper easily.... or an exacto knife to clean it...)
but no pblm so far....

also.... during the whole process, I do NOT remove the protective paper on BOTH side of the lexan....
So, after drilling, both protective paper is STILL ATTACHED...

maybe your spade bit's cutting point is dull ??.... could that be a problem ??.....

[gndprx]

One quick tip when working with plastics (lexan, acrylic, pvc, etc...)  Use a slower setting on your drill or drill press.  The faster you go, the more heat will be generated and you will end up with melted edges (possibly melting back together in the case of jig sawing and such)

Also keep a spray bottle of water handy (or wd40 if working with metal/aluminum) and keep the piece that you are drilling cool.

One other trick is to always drill with a backer board.  A simple piece of scrap wood that will be on the back side of the piece you're drilling.  This helps prevent chip out or rough edges when your bit passes through the last layer of plastic.

Also, don't use a lot of preasure.  Let the drill and the bit do the work for you.  The more you press, the more likely you are to crack the plastic.

Just some helpful tips

[rampy]

So far some good advice above....

But I have to ask... aren't you using your drilled MDF as a guide with the lexan clamped to it?

A hole saw is probably right for htis application.

If you have to buy another sheet of lexan the 10 dollar bit would have paid for itself =P

*shrug*

rampy

[REBIRTH]

Something must be wrong, because from my experience Lexan is just about as easy as wood to cut.  A couple of hints in case you aren't doing this already:

1)  Straight lines - use a router with a straight bit.  I did my first couple of CP overlays with the Lexan cutting tool thing (basically a knife) - you score it about 10 times and crack it.  Works ok, but I then saw a post on here about using a router... Whoo Haa!!!  Thing cuts like butter, perfectly straight.  Comes out 10 times better than the cutting tool...  Makes a heck of a mess though, be ready to have tiny shards of plastic all over your house.

2)  Holes - For button holes I used the same 1 1/8 boring bit I used to drill the button holes in the wood.  For the trackball hole I used the big 3" diameter hole cutting bit.  Any drill bit should do fine. Sandwich the lexan between your CP and a piece of scrap wood (CP on top).  Clamp that baby down good.  Now, using your CP holes as a guide, drill into the lexan until you hit the scrap wood underneath.  Doing it this way guarantees the lexan holes matching up with the CP holes.

3)  rough edges - you can smooth a rough edge pretty nicely with an exacto knife or razor blade if it is in a hole, or just use the router again if it is on a straight edge.

Don't give up!  If you already ruined some lexan, just re-use that as a training thing until you get it right.  The big thing is putting it in between the wood and clamping it down tight.

Doug

[hulkster]

yep thats the big thing alright, and i dont have any clamps!  i guess i just got in too much of a hurry and just started cutting without being careful.  no excuse.  but i dont have any clamps, but i guess i could just the sandwhich technique and make sure everything is lined up right.  thanks for the tips guys, i think ill go back and do everything slow and steady and be more careful.  

[REBIRTH]

yep thats the big thing alright, and i dont have any clamps!

If you are planning on screwing/bolting the lexan to the CP when you install it, dso that now and get the thing clamped together that way.  

- or -

Put the CP sandwich on the floor and stand on it, then drill down from there (watch your toes ).  Should be enough weight to keep things in place.

[hulkster]

well i thought about that, but should i put down my contact paper as well?  im not doing artwork, just contact paper...should i apply that, bolt the lexan to the cp and then drill?  also, the paper is still on both sides of the lexan.  should i remove that as well?

[hyiu]

well... Home depot has those clamps for like $2 a piece or so.... they're good enough to clamp 2 pieces of 3/4 inch wood....

so.... if you can afford like $10.... get a few of them....
they can be handy later on.....

or.... in addition to standing on it yourself.... (somehow... I don't feel its good to stand on it if you are the one drilling it...) maybe ask a friend to step on it for you...)

also... DUCK TAPE will help in this case to help hold them together.....
(this should be a CHEAPY additional solution...)
but duck tape might not be strong enough by itself !!!...
so.. beware....

good luck....

[AlanS17]

Yeah I was going to recommend standing on it, too. Your other option (what I did) is to cut the shape out and actually screw the 2 pieces together in the spots where the lexan is going to be screwed down, anyways. This won't work for people that aren't screwing their lexan down, but I imagine a good number of people will because buttons alone won't hold that stuff in place.

[rampy]

duct tape not strong enough?! blasphemy!

LEAVE the protective paper/plastic on until you're absolutely done!

you can wait on the contact paper till you're ready, later...

(you'd cover the whole control panel, and then just make slits through the holes in an x formation... no need to spade bit or hole saw bit drill through contact paper and gum up the works =P )

*shrug*

rampy

[bigmoe]

Yeah I was going to recommend standing on it, too. Your other option (what I did) is to cut the shape out and actually screw the 2 pieces together in the spots where the lexan is going to be screwed down, anyways. This won't work for people that aren't screwing their lexan down, but I imagine a good number of people will because buttons alone won't hold that stuff in place.

I had assumed that you needed to pre-drill the screw holes in the lexan.  Is that not true?  You can just screw it down cold?

[CanStick]

Myself, I use a 1 1/8" Forstner bit to drill through both the wood and the Lexan...and it creates very clean holes in both the wood and the Lexan.  And, Forstner bits are pretty cheap.  You can get them just about anywhere.

The method I use....

First, I drill the holes in the wood.  Clamp / screw the Lexan on top, flip it over, and then drill through the Lexan.  That way the holes line up perfectly....

Actually, I have started using a laminate trim bit in my router to route out the holes in the Lexan...but flipping it upside down and drilling through works good too!

Terry.

[AlanS17]

No you need to predrill the screw holes, but screw holes are alot easier to center than button holes. When you get them in place it will help you drill the rest of the holes.

[gndprx]

Home Depot by me sells 2" spring clamps for $1 a piece.  I have about 20 or so lying around my shop at the moment (aside from all the quick clamps, bar clamps and misc other clamps)

You can never have enough clamps  

[hyiu]

yeah..... more clamps is always better....
 haa haa haa....

one for each finger and one for each toe....

haaa haa haa....

ok.... that hurts....  

[hulkster]

well i just drilled my lexan for the second time and all i have to say is.....God bless this forum!!!!  my lexan looks sweet and now im off to build my monitor support.  this is really cool...sweet titties...yeah that about sums it up.  

[AlanS17]

hahaha What method did you use? What did you do differently?

[hulkster]

i used a combo of methods actually.  i made the "cp sandwich" and then drilled the holes and put carriage bolts through 4 corners, then just drilled holes using a spade bit.  ive already spent a big booty load of money, so i didnt want to spend anymore, but it came out fine.  i dont know if it has scratches or not, but at this point, i dont care.  it will protect my contact paper and cp.  

[Dr. J]

Man, I wish I would have seen this a little earlier.  I just posted all about how I did it on this thread http://www.arcadecontrols.org/yabbse/index.php?board=1;action=display;threadid=9677

My advice is to stay away from the hole saw.  That also melts plexi, but it will get stuck inside and cool down while in contact with the metal.  Then what you have is a useless hole saw.

[rampy]

You can use a holesaw... just go slow (as in patience and slower drill speed)... fwiw.

*shrug*  although I'm sure Dr. J's spade bit instructions would work as well.

Rampy

[HeadRusch]

My experience with Hole Saws is that my 1 1/8" hole saw SUCKS......but my 1 1/8" spade bit works fine.

2" and 3" hole saws work great....but the 1 1/8" diameter just casues that sucker to gunk-up and start burning my wood!  (I could just have a bad bit too though......)

PS: For what its worth, just clamp your lexan down on your CP and cut em both at the same time, which is what I did and it works out completely fine...no problems with holes not lining up.

Also, you can't expect to drill a plastic at full speed without melting....I used a slower speed on my drill and never had a hole melt on me, if you guys are going gangbusters  COMMON SENSE people...you got it, use it!