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Discussion Starter · #1 ·
Hi everyone new here. I did a search for a hobby forum and found this place woohoo!!

Im having a lot of fun building LED lights for around the house. I use the little flexible LED strips that are available online. They come with a sticky tape on the backside so you can attach them somewhat securely to cabinets for example.

What i want to do is attach the LED strips to sheets of plastic to make them sorta rigid. I want to epoxy them down even though they have the sticky tape.

So the reason i came to this site is for plastic sheet advice. I would like something around 1/8'' thick. But most important is i want to use an epoxy instead of a plastic solvent to glue onto it.

There are so many forms of plastics im totally confused. Anyone have advice as to what type of plastic sheet i need to look for? Ideal would be a plastic that cuts pretty clean with a table saw or skill zaw without cracking. Also i need regular 2 part epoxy to stick to it. Its fine if i need to rough the surface.

Thank you for reading.
 

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A plastics shop will sell sheets of thicker styrene or plexiglass. Plex can be cut with a band saw and comes in colors besides the usual clear. You can glue things with epoxy or solvent based glues. Sheet plastic is pretty slick and even 1/8" can have some flex, so epoxy may just peel off. Epoxy doesn't always last a long time. I have had things that were glued with epoxy come apart X years later.
 

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Sheet acrylic comes to mind. Its readily available and sold in pre-cut manageable sizes in many hardware stores like Lowe's and Home Depot. They also sell inexpensive scoring tools ($1-$2) that work sort of like glass cutters (only easier). It'll take some practice to learn how to 'strike' the score line but this method is good for making straight pieces without much (or any) sanding required. If you do have to sand it I use a coarse then a fine sanding sponge to clean up the edge. Look here and scroll down to No. 4 for a description: http://www.bcae1.com/plexi.htm

Does the adhesive backing come pre-attached to the LED tape? Not sure I would want o mix 5 min epoxy with spongy double sided tape. Instead of epoxy you may be able to use hot melt glue to apply it to the acrylic strips. Hot melts adheres to acrylic and works well in room temperature applications. If you need remove it simply use a little rubbing alcohol to break the bond.

Hope this helps.

MattL
 

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I agree - go with either sheet styrene or sheet acrylic. I would advise using something like "Goo gone" or even WD-40 to remove the adhesive from the LED strips, then clean them up with alcohol. Two part epoxy will adhere the LED strips to either the styrene or acrylic nicely. It has been my experience with the LED strips that the adhesive that comes with them starts to let go after a while. Personally, I use one of the "super glues" to hold down LED strips.
 

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Styrene is softer and can be glued with solvent glues like model cement. Acrylic is just a non trademarked name for Plexiglass. Sort of like Velcro versus "hook and loop fastener".
Been experimenting with cementing acrylic sheet and styrene lately. I've gotten good results using our favorite Tamiya Extra thin cement to bond them together. Cemented styrene pieces to acrylic sheet a couple of weeks ago and got a really strong bond. Maybe not as fast as styrene to styrene but it certainly works AND without any crazing.

Earlier today I cemented up some acrylic sheet pieces . First sample was two sheets cemented to face to face. Second sample was a sheet edge cemented to a face. Too early to tell but both are holding up well to reasonably strong pull tests after a few hours of curing. I'll try torsional testing tomorrow.

I suspect that there may be a more mission specific cement but the Tamiya looks promising in a pinch if its for light-duty applications.

Regards,
MattL
 

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Tamiya now has an ABS cement that may be a bit "hotter". Also, IPS Weld On Cement is formulated for Plex/Acrylic and will bond styrene. I forget which Weld On is best. They have several; i.e. Weld on #2 #4 etc.
 

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Well to glue a Magnet you will probably need to use CA glue
Not sure about that... CA glue joints don't take impacts well. I've had success using 5 min epoxy to hold them. Maybe a dot of CA to tack it in place followed by 5min epoxy to encapsulate?

I also used JB Weld but you've got to work quickly when placing the magnet or the JB will attack your fingertips (go ahead and ask me how I know this :freak: )
 

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I suppose it depends what you are going to do with the item. If you are gluing a magnet to the plastic and then sitting it on a shelf then CA glue will do fine. If its some item that is going to be battered about like a Cosplay weapon then it will need to be reenforced. Personally I am not a huge epoxy fan as it degrades with time and will just peel off. I have stuff glued with CA glue 30 years ago that are just fine but 30 year old epoxy joints just fall apart.
 

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Discussion Starter · #13 ·
Thats interesting about the epoxy failing. CA is cool with me. Waiting on the magnets to show up. Guess i will sand a little and see how it goes.

Hey i was looking up the Home Depot website. Anyone have opinions on Lexan vs Acrylic? Do both accept epoxy or CA to the surface?
 

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Lexan as I know it is rubberier and more flexible. They mold RC car bodies and boat hulls out of it for that reason. Its harder to paint becuase it flexes and paint (and glue) just peel off.

What are you trying to make that would require the use of these somewhat special plastics? (that you couldn't do with styrene that is much easier to work with). You can get styrene as thick as plexiglass, lexan, etc.
 

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Discussion Starter · #15 ·
I just want a plastic that i can use epoxy or CA on instead of a special weld type of solvent.

Because im attaching the LED strips to it. Not doing plastic to plastic.

I have some plastic from about 2 years ago. Its grey and i bough a bunch of special weld type of glue. Wonder what type it is. Might be able to find an online receipt.

Again thanks. Heading to home depot now. Check out the saw blades and plastic.
 

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You can use CA on styrene as well. CA sticks better to styrene than acrylic, lexan, etc. IMHO as well. The grey plastic sounds like ABS. CA glue does not work well on ABS it just sits there and doesn't cure. Plastruct sells a lot of grey ABS plastic in hobby shops and a special glue for it. But its a solvent based glue...
 

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Wopachop, I'm curious. Do you know what type of material the LED tape is made from? Is it polyamide, teflon, something else? That certainly comes into play when deciding which glue or cement works best. If its either of the two I mentioned getting CA or epoxy to stick would be a challenge. At that point the choice would be something like double sided tape (either foam or film) or hot melt glue...
 

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Discussion Starter · #18 ·
Well i thought i had styrene but after reading the thread now i think it must be ABS.
I used the ABS cement in the white bottle trying to weld two pieces face to face. I know its really thin and works by capillary action but i tried spreading the cement on the face of one piece. As fast as i could i put other piece on top and held in place for thirty seconds. Felt real slippery so i dont think it died before i mated two surfaces. I set a heavy piece of wood on top and waited 10 mins to check it. Nothin...didnt bond worth a crap.

Since its ABS im not gonna even toy with it. Thinking now i want either black acrylic or styrene. I dont want much if any light to shine through. I guess the black acrylic is opaque im thinking that will be good enough. Or maybe styrene.

Home Depot only had 2 thickness choices. One is too thin and the other too thick. So now im back to looking online. I need the stuff now so getting a little frustrated and confused as to what i want/need.

The LED strips have a 3M sticky tape back. Its very thin. Not a foamy type of tape. I will go take a pic real quick.

Once again thanks. You guys nailed it was ABS before i even came to post pics of it.
 

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The black acrylic/plex I had looked opaque but sort of glowed if you put a light behind it. Sort of like how a glass bottle can look dark but is see through when you shine a light in it.

If light bleed is an issue PAINT IT. Paint will stick best to styrene compared to plex.
 

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Discussion Starter · #20 ·
Very cool thanks! Leaning more and more towards styrene now. I live in southern California. Is there a place anyone can recommend buying from? Either online or a walk in store. I went into the plastruct place a year ago. Was expensive and nobody wanted to help me with my questions. Told myself never going back. Will be driving between Hesperia/San Clemente/San Diego next couple days. Maybe there is a cool place along that route.

Here is a pic of the LED strips.

In terms of painting my only concern is durability. Some of the lights will get dirty with oily fingers and being able to wipe down with alcohol would be preferable.

"Glowing" of the plastic is not too big of a deal.
 

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