posted
As Roseannadanna used to say, "Wayne, you ask a lot of questions". We use polycarb for all our plasic faces. 1/8" is fine for that size. A shear is the best way to cut, but you can cut with a saw, don't know what blade.
-------------------- Wright Signs Wyandotte, Michigan Posts: 2785 | From: Wyandotte, MI USA | Registered: Jan 1999
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unless you are going big I would stick with the acrylic unless you can get the polycarbonate in the size you need. It comes in rolls usually 6' wide so thats a lot of material to store. The poly is of course a better material if you are concerned about impact or abuse, the stuff is pretty bullet proof.
You can cut either on the saw, the poly will not chip but the acylic will unless you tape a line where you are going to cut or use a sharp carbide blade.
I believe the saw blade you refer to has no offset meaning that the teeth are in a perfect row as opposed to staggered like norm.
Yes the poly will last longer but the acryic last plenty long by itself on most jobs
I normally use 3/16" on backlit signs as they fit nicely in the channels
By the way the poly is a real bear to handle since it is so floppy, kind of like nailing jell-o to a tree.
Whew, I think that does it, hope it was a help
-------------------- Brian Stoddard Northwest Wholesale Signs
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The main options have already been covered. Both will cut fine on a table saw with a sharp blade, carbide or high speed steel. If the material is premasked with paper masking, so much the better. If not, apply masking tape to the plastic where you will cut it. This prevents the plastic from melting, gumming up and resticking to itself. Masking tape on the cut line makes for a much cleaner cut edge.
It should go without saying, but wear safety goggles. One time, I found one of my employees cutting acrylic on the bandsaw without eye protection. I told him to put the goggles on and said to him: "You haven't lived until you've gotten a hot piece of plex in your eye." A few seconds later I heard the shout: "I'm really living now!"
-------------------- David Harding A Sign of Excellence Carrollton, TX Posts: 5089 | From: Carrollton, TX, USA | Registered: Nov 1998
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Talk to your plastics supplier about cutting it to size for you. You will pay more per square foot for a cut piece but won't be stuck with the rest of a piece that you might not use for a while. Also if it breaks or chips while cutting, it will be on them.
As far as thickness goes check the width of the frame it is going in to see what it will handle.
There is a newer type of polycarb/plexi called "SU grade" (I think) Tougher than regular, but won't yellow like lexan and not as expensive. Ask your supplier.
posted
Wayne, Sheet acrylic should work just fine for a sign face that size, just don't use "FF" grade, use 3/16" "GP" or "SG", it's a whole lot tougher than "FF". Polycarbonate tends to turn yellow and get brittle with age. You also don't need to buy a 10'sheet as acrylic comes a little bit over size. A 4x8 is actually somewhere around 50" x 98". Acrylic is also easier to saw. Polycarbonate has a tendency to catch on the blade and crack. Acrylic also glues much better than poly.
-------------------- Jerry Mathel Retired Grants Pass, Oregon signs@grantspass.com Posts: 916 | From: Grants Pass, OR USA | Registered: Dec 1998
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I noticed some of the posts mentioned the yellowing of polycarbonate. I almost mentioned that in my earlier comment but didn't, in case the problem had been solved (I did not want to appear any more ignorant than I already am). I guess yellowing is still an issue. I last used white polycarbonate about 20 years ago and it looked like an old newspaper in a few months.
The post about getting your supplier to cut it is a good idea. Here in Dallas, I now have Regal Plastics cut all my faces to size. It is a few percent more per square foot, however, all the material is stocked at their expense. There are several types of high impact acrylics, such as Plexiglas DR, that combine strength, fade resistance and a lower price than polycarbonate. Your face is only a foot tall, so it will be quite strong, no matter what material is used.
When replacing the faces, measure the old faces, not the can it is in for replacement sizes. Plastics expand and contract greatly with temperature changes. An 8' piece of acrylic will change length up to 1/2", depending on the time of the year. The retainer on the can will allow movement. The can will usually be at least 1/2" longer than the face and 1/8" to 1/4" taller to allow for expansion clearance. If the old faces are not available, cut your face at least 1/2" less length than the can and 1/8" smaller on the vertical dimension. Just don't cut so short that it pops into the can.
-------------------- David Harding A Sign of Excellence Carrollton, TX Posts: 5089 | From: Carrollton, TX, USA | Registered: Nov 1998
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acrylic is a bit cheaper but i only use polycarb you will know why after cracking or breaking a face wile moveing it or installing it like i have in the past. (and i hate having to do something twice!)and polycarb you can roll up wile storeing and transporting. one of my local supplies carrys lexan in roll stock cut to lenth to any size you need in roll widths 38" 52" 64" 76" and 100" this saves a lot on waste and cost. and the thiner matteral should work just fine with the sizes to talked about (why over build if you dont have to and save $$$$) In the past lexan came with only one side with uv protection (stops the yellowing and breakdown) and it was labled with this side face out. but i think they are makeing it uv 2 sides.....ask your suppler as far as cutting... use a carbide tiped blade with the most teeth per inch you can find to fit your saw. before I got my large panel saw (I love that baby) for small stuff i used the table saw but for large and long signs I would use a scrap sheet of plywood under my lexan on my work bench or saw horses, clamp a straght edge to the lexan and plywood, set the depth of your skillsaw blade just slitely more than the thickness of your lexan stock and cut running your skillsaw down the straght edge and slightly into the scrap plywood. doing big stuff on a table saw can get a bit wild and floppy. I have a old sheet of 4x8x5/8" plywood that ive had for over 15 years in shop that I use this for thats all cut up on one side from all the use...and when im not useing it i just flip it over to the snooth side and use it on saw horses for temp. work space
-------------------- Aaron Haynes Aaron's Signs & Windows Napa Ca aa4signs@sbcglobal.net ------------ Important Rule For Life: "Look out for number one... Don't step in number two" ------------ If your never the lead dog on the sled...the scenery never changes. Posts: 241 | From: Napa Ca. USA | Registered: Dec 1998
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posted
My two cents....Acrylic is cheaper yet acceptable. 1/8 for both will work just fine with only being 12" high.
The only thing that will cause the acrylic to have a shorter life is kids walking home from school deciding to huck a rock at it (like that will happen)ha.
posted
My two cents....Acrylic is cheaper yet acceptable. 1/8 for both will work just fine with only being 12" high.
The only thing that will cause the acrylic to have a shorter life is kids walking home from school deciding to huck a rock at it (like that will happen)ha.
Not sure if this was mentioned. Acrylic is much more scuff/scratch resistant than Lexan. Lexan will scuff badly even if you wipe with a rag. For this small a sign, I'd use acrylic. Yes it usually comes over size, so you won't need a 10' piece. Also if you use polycarbonate (Lexan),only wipe it with alcohol or the special cleaner.Lacquer Thinner or other "hot" solvents will turn it to mush and ruin it. If you use polycarbonate, make sure you remove the protective poly mask 24hrs. before you apply graphics. It needs to "breath".
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Hi Wayne;I usually just call my plastic company and they cut what-ever size I want.To answer your thickness question it depends where the sign is going.1/8 can be sloppy and really flop around.If it's where there is no wind should be alright.
-------------------- Randall Campbell Randy's Graphics, 420 Fairfield N. Hamilton Ontario Canada Posts: 2857 | From: Hamilton Ontario Canada | Registered: Jan 2002
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Now I feel like the kid in the candy store. I ordered some polycarb embossed pan faces last year. I don't guess they make those out of acrylic do they? Looks like there is now a UV protected version of either one though.
Thanks everyone
-------------------- Wayne Webb Webb Signworks Chipley, FL 850.638.9329 wayne@webbsignworks.com Posts: 7404 | From: Chipley,Florida,United States | Registered: Oct 1999
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Lots of good replies here, but I have to disagree with David Harding on one point. Measuring the existing faces is not a good idea. They may have measured wrong themselves and screwed it into the retainer wall to adjust a bad fit. Had that happen to me recently, should have known better.
-------------------- Wright Signs Wyandotte, Michigan Posts: 2785 | From: Wyandotte, MI USA | Registered: Jan 1999
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posted
Good point, David. I have seen faces obviously done wrong, Those should not be used as templates. A little forethought and common sense can go along way to insure proper expansion clearance.
David Harding
-------------------- David Harding A Sign of Excellence Carrollton, TX Posts: 5089 | From: Carrollton, TX, USA | Registered: Nov 1998
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