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Main => Main Forum => Topic started by: kiwasabi on July 01, 2014, 10:03:58 pm

Title: Can scratches be removed from clear acrylic/plexi?
Post by: kiwasabi on July 01, 2014, 10:03:58 pm
Hey guys,

I have a 1/4" thick piece of clear acrylic for my monitor glass/bezel, and it got some scratches in it when I sent it to the printers. I was going to have them print directly on it, but they couldn't figure out how to. So they did a clear decal instead, which ended up transparent instead of translucent. So I had them remove that, and somehow they managed to leave some large scratches down the middle of the piece... Anyway, is there anything I can do to remove the scratches or at least make them less noticeable? I would rather not have to buy another $30 piece of acrylic.

Adam
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: lilshawn on July 01, 2014, 10:16:22 pm
pick up one of those headlight restore kits... the compounds are made for plastic and you should be able to get it nearly gone, or at least less noticeable. you'll want to use a light touch with it, acrylic is pretty soft and it doesn't take much.
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: kiwasabi on July 01, 2014, 11:21:55 pm
pick up one of those headlight restore kits... the compounds are made for plastic and you should be able to get it nearly gone, or at least less noticeable. you'll want to use a light touch with it, acrylic is pretty soft and it doesn't take much.

Good idea, thanks Shawn!
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: BobA on July 02, 2014, 12:37:53 am
If the scratches are deep you are better off buying new acrylic then spending many hours trying to polish out the scratches.    It is a time vrs results thing.
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: kiwasabi on July 02, 2014, 02:45:07 am
If the scratches are deep you are better off buying new acrylic then spending many hours trying to polish out the scratches.    It is a time vrs results thing.

Yeah I'll see how much the spray costs. The scratches aren't super deep I don't think. I have a nice piece of glass that's perfect but would need to get it recut to fit. I may just do that, I'll compare costs.
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: Le Chuck on July 02, 2014, 09:43:06 am
Break out the steel wool and blowtorch.  It's time to practice "flame polishing" then when you fail miserably and have a charred yellow bubbled mass you'll be really glad you followed my advice!

Or you'll totally succeed in restoring that damaged plastic. 
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: Xiaou2 on July 02, 2014, 01:27:11 pm
Steel wool is good.   But if its deep... you may need fine to mild grit sandpaper first.. to get down far enough past the scratch depth.

 Im using grade 0000 steel wool for restoring some laptop lids.   Scrub down past the scratch, and then lightly feather the area.   As the dust build.. if can clog the wool a little.. making it hard to remove material.   Spank it clean with a few hard taps, nearest the floor and or over a trash can / papers.   The end result should be a hazy spot, but smooth to the touch...

 Then I use this polishing wadding that has seed-oils.. called "Never Dull".
The stuff is a Miracle in a can.    Amazing mirror finish results, with very little effort.   Rub it on and polish away..   then wait a few seconds for it to haze over.. and use a paper towel or cloth to buff it to a gloss finish.   Repeat as needed, until you get the gloss level you desire.

 Practice on a scrap piece first.

 I would stay away from the flame trick.   Its nearly impossible..  and only certain kinds of plastics are workable at that.
Even the most experienced flamers - ruin plastics on accident.  Ive watched it happen.. and then asked him for a different pinball ramp that wasnt warped / bubbled.

Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: BadMouth on July 02, 2014, 01:53:06 pm
The headlight restoration kits contain a little 2000 grit sanding pad, an either slightly smoother or rougher pad (can't remember atm), the polisher drill attachment and plastic polish.

If you already have some sort of buffing pad, you can just buy the plastic polish.
(http://images.meguiarsdirect.com/imagesEdp/p84711b.jpg)
You're probably going to need more sandpaper anyway.  You might need to start out with a more aggressive grit depending on how deep the scratch is.

Basically what you're going to do is sand the the scratch until the area around it is just as low as the bottom of the scratch.  At that point, the scratch will no longer be discernible from it's surrounding area.  (it will all look messed up)  Then you'll use progressively finer sandpaper to make the scratches created by the previous round of sanding smoother.  When you work your way up to 2000-3000 grit sandpaper, you can then move onto polish (which is like even finer grit sandpaper).  The polishing stage should make it clear again.

It's a lot of work removing enough material to get past the scratch, then getting the surface smooth enough to be perfectly clear again.
Personally, I'd rather just pay the $30.
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: lamprey on July 02, 2014, 02:04:16 pm
Any chance you would consider just buying glass as a repalcement?
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: Xiaou2 on July 02, 2014, 05:10:51 pm
Ive done the sandpaper stuff before..  but I have to say, the fine grit steel wool is far superior in results,  takes far less effort and error.

Also, the great thing about "Never Dull"  is that its very easy to get good results quickly with it.. and unlike typical polishes, it doesnt make and or leave a smeary then flaky mess.   (common to polish such as Novis)     Working the buffer / buffing discs.. is a real pain.   That crayon like substance flies off the wheel and gets on everything.

 So far, Ive only used this on black laptop lids, that have deep scratches and a matte paint finish.   Im able to make them shine in high gloss, and you would never know there had been scratches / damages.    One lid of average damages takes me about 8 minutes.  More or less.. depending on the level of damages... but even the worst cases.. take less than 12 min.   I believe.

 Have not tried this on other materials yet, but will be testing soon.

Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: kiwasabi on July 02, 2014, 08:25:24 pm
Ive done the sandpaper stuff before..  but I have to say, the fine grit steel wool is far superior in results,  takes far less effort and error.

Also, the great thing about "Never Dull"  is that its very easy to get good results quickly with it.. and unlike typical polishes, it doesnt make and or leave a smeary then flaky mess.   (common to polish such as Novis)     Working the buffer / buffing discs.. is a real pain.   That crayon like substance flies off the wheel and gets on everything.

 So far, Ive only used this on black laptop lids, that have deep scratches and a matte paint finish.   Im able to make them shine in high gloss, and you would never know there had been scratches / damages.    One lid of average damages takes me about 8 minutes.  More or less.. depending on the level of damages... but even the worst cases.. take less than 12 min.   I believe.

 Have not tried this on other materials yet, but will be testing soon.

That's promising, although this is for clear plastic so that's a bit different.

Any chance you would consider just buying glass as a repalcement?

I think that's what I'll end up doing. I can get 1/4" tempered glass in 24 x 28" for $32. I have a piece already but apparently you can't recut tempered glass (I read you can machine it down but the glass company says there's nothing they can do). At the end of the day it's a small extra expense.

It's a lot of work removing enough material to get past the scratch, then getting the surface smooth enough to be perfectly clear again.
Personally, I'd rather just pay the $30.

Yeah, I think I'll just bite the bullet. I can get a piece that fits better anyway since right now you have to bend the plexi to get it to fit or remove it.
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: Dungeonsdeep on July 02, 2014, 08:42:45 pm
I don't want to be that guy that trys to answer your problem in the least helpful way by suggesting something totally off topic....

But have you considered a sheet of glass? I think in the end, it looks better, you don't have to worry about scratches, and it isn't too expensive.
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: kiwasabi on July 02, 2014, 09:26:23 pm
I don't want to be that guy that trys to answer your problem in the least helpful way by suggesting something totally off topic....

But have you considered a sheet of glass? I think in the end, it looks better, you don't have to worry about scratches, and it isn't too expensive.

Lol. Someone else asked that above, I think that's what I'm going to go with. I like it better than the plexi because it isn't flexible and seems more professional.
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: Dungeonsdeep on July 03, 2014, 10:12:04 am
Just make sure it is tempered, won't be as prone to shattering.
Title: Re: Can scratches be removed from clear acrylic/plexi?
Post by: BadMouth on July 03, 2014, 10:16:03 am
Also, the great thing about "Never Dull"....

I always have a can around, but have only ever used it on metal.  I will give it a try on other surfaces.