working with acrylic

[Vicki Rivrud]

I would appreciate some feedback from those who work with acrylic.

I have a fairly new customer with big contacts so I am protyping several differant products but no big sales yet.

They are driving me nuts. Although we are both perfectionist and I strive to produce A+ products, the acrylic whether it is mirror or cast always seems to have a blemish, pin-dot or slight scratch that I just can't seem to buff out and I am using the Novus products.

I do alot of LED lighting items and when lit if there is a "defect or imperfection" it refracts the light as the lit always finds its exit point.

Now I'm not talking about huge scratchs - perhaps a tiny ding or a pindot.

Do I walk away ( in this economy) or is there I trick or tip I am missing?? I am a very diplomatic person but I do have my limits.

Any advise would be appreciated.
254843

Thanks
Vicki

[Ross Moshinsky]

Like everything, there are levels of quality in every product. Sheet goods simply are not produced at the standard they once were. You're probably going to have to upgrade to a higher quality acrylic.

I'd call up some acrylic suppliers and fabricators and see if they can't help you find a solution.

[Richard Rumancik]

Even if the material is perfect at the factory there is nothing to say it won't pick up a scratch or mark when shipped, handled by distributor, cut to size, shipped to you, handled in your shop, etc etc. So getting more expensive sheet might not necessarily solve it. It is hard to evaluate the magnitude of the problem from the picture, especially when the problem is mainly noticed when the light is on.

I guess if the customer expects something that is not practicable to make then you just have to say so. When appearance parts are evaluated in industry usually a "viewing distance" is specified for quality-control inspection purposes. The customer should be reasonable in that is something is normally viewed at say 24" you should not inspect it at 4".

I really can't tell the nature of the material or the damage from the photo. Is there any other way of repairing a pit or small scratch? Maybe some kind of solvent with a syringe?

[Walt Langhans]

Maybe some kind of solvent with a syringe?

That could work. When you put 2 parts of Acrylic together they are chemically welded so I'm betting that if the dot is small enough you could make it disappear. Check out this video from TAP to see what I mean.

http://www.tapplastics.com/product/repair_products/plastic_adhesives/tap_acrylic_cement/130

Also I agree with Richard, if someone isn't going to be putting their nose 4" from it on a regular basis then it won't be noticed.

[Steve Clarkson]

Also.......double check your artwork.......if the nick is in the same spot on every piece, it might be a really small spec on your corel file that you normally wouldn't see unless you zoom in really close.....but the laser can still see it and "engraves" it.

[Vicki Rivrud]

Thanks for the advise, yes I have double checked and rechecked and even watched the laser engrave to see if there is a stray - not so.

It's many dings and nicks I find after I remove the factory mask. So perhaps a better quality source or distributor would be my next step. I am using Chemcast 3030 green edge.

BUT . . the 2" scrutiny is what I really think the problem is . . . I'll post a photo of it lit . . . when viewed from afar I can't see it but IF I'm upclose - like in the hands of a possible buyer well then it could possibly be seen, if you really look closely.

This is funny that you mention the 2" eyeballing - I also work with a jeweler who actually brought out the loupe to "inspect" the anodized aluminum engraving I did on his iPADs.

Back to the acrylic - - Novus with a light touch of the orbital took out more than my elbow grease, so most the stuff finally dissappeared.

Although customers are KING, it can be a royal pain at time when they give nose end inspection :)

Vicki

[Rodne Gold]

Cast acrylic is made differently to extruded , its a liquid cast between 2 sheets of glass with a rubber gasket separating the 2 sheets , left in an autoclave under pressure and high temp to polymerize. you often get small flaws , inclusions , and bad thickness variations.
Extruded is always better as its extruded between rollers and doesn't have the variances and the major handling processes that cast does , you can try extruded , tho it wont engrave well.

[Chuck Stone]

for pinholes like that, I'd try a needle tip on a bottle of super glue.
put down a tiny dot and immediately wipe it off, leaving it level. If
the dot is too big, wiping it will leave a smear. So a little practice on some
scrap material will pay off.
Woodworking stores have those needle tips. I have some if you need them.

[Paul Phillips]

Vicki, have you tried all the Novus products including the #3 heavy scratch remover and polishing kit? I can usually work out a small scratch by hand starting with the #2, if that doesn't work I try the #3, keep in mind though that the deeper the scratch you remove the harder it is to get it to look perfect, you have to "feather out" the area your'e working on so you don't get a divot/low spot that looks distorted. I had a $1200 piece of 3/8"x5'x12' 3030 acrylic that I had routed with a bunch of 3d golf balls in it, the installers scratched it and I had to fix it, not fun.
http://www.novuspolish.com/products.html
Paul

[Vicki Rivrud]

for pinholes like that, I'd try a needle tip on a bottle of super glue.
put down a tiny dot and immediately wipe it off, leaving it level. If
the dot is too big, wiping it will leave a smear. So a little practice on some
scrap material will pay off.
Woodworking stores have those needle tips. I have some if you need them.

HI Chuck,
Do you think that the super glue will stop the light from finding it to exit??

I know exactly what you are using - -got some . . .Thanks

Vicki

[Vicki Rivrud]

Vicki, have you tried all the Novus products including the #3 heavy scratch remover and polishing kit? I can usually work out a small scratch by hand starting with the #2, if that doesn't work I try the #3, keep in mind though that the deeper the scratch you remove the harder it is to get it to look perfect, you have to "feather out" the area your'e working on so you don't get a divot/low spot that looks distorted. I had a $1200 piece of 3/8"x5'x12' 3030 acrylic that I had routed with a bunch of 3d golf balls in it, the installers scratched it and I had to fix it, not fun.
http://www.novuspolish.com/products.html
Paul

YUP! Use it all the time . . . . I know you have to have a light touch when polishing out scratches or else you wind up with fun-house mirror or swirls & divots.
I just got so frustrated that the acrylic is scratched or blemished under the mask . . . . this is actually what the customer is seeing.

Rodney explained it perfectly so I have to learn to "tell" customers that there has to be a +/- tolerance for minor pin spots or factory blemishes. I am going to try the super glue fix on some scraps to see if that is a good solutions ofr some of the blemishes or pin dots. Then again when you eyeball it up close when it actually is seen afar and the fact that its going to go on a car or truck or rv - the first few trips on the road and it will have pits from stones & flying asphalt.

I've learned that acrylic is not a perfect substrate. And we don't live in a perfect world :)

Vicki

[Chuck Stone]

HI Chuck,
Do you think that the super glue will stop the light from finding it to exit??

Absolutely. Super glue is an acrylic. I use it as a finish all the time and I use it
to fill in scratches in plastic. If you get it level, it will work.
I would use thin super glue .. the fresher, the better.

[Vicki Rivrud]

I would appreciate some feedback from those who work with acrylic.

I have a fairly new customer with big contacts so I am protyping several differant products but no big sales yet.

They are driving me nuts. Although we are both perfectionist and I strive to produce A+ products, the acrylic whether it is mirror or cast always seems to have a blemish, pin-dot or slight scratch that I just can't seem to buff out and I am using the Novus products.

I do alot of LED lighting items and when lit if there is a "defect or imperfection" it refracts the light as the lit always finds its exit point.

Now I'm not talking about huge scratchs - perhaps a tiny ding or a pindot.

Do I walk away ( in this economy) or is there I trick or tip I am missing?? I am a very diplomatic person but I do have my limits.

Any advise would be appreciated.
254843

Thanks
Vicki

Here is an updated photo showing the engraving detail and the pin dots after some Novus & buffing
Slightly noticeable but something I can live with. I'll try the super glue suggestion on another piece.

254938254939

Thanks for all the input and suggestions
Vicki

[Greg Facer]

Hi Vicki,

Edge lighting acrylic is a pain that way. The worst part is that the customer or end user will, 100% of the time, make the same scratches (assuming they are the very minor variety) in the first week of handling.

Extruded probably is better than cast, and paper mask is probably better than plastic (certainly for the laser it is).

I'm in the better plastic camp, but for green edge that will be tough. I have found that in for the smallest blemishes, touching it with *anything* tends to make it worse. Maybe superglue works, it would be interesting to know.....it would fix the mark, so if it doesn't make the surrounding sheet worse then it'll be a success,

Greg