Product till fill engraved areas as im etching?

[adam smiz]

So this is a long shot, as I've found nothing indicating it exists. But here is my issue:

I am engraving large complicated clear acrylic pieces that then need to be filled in with black so you can see everything that's etched. Currently I leave the protective poly cover on the acrylic and use it as a sort of "tape". I then spray paint it with a water based acrylics spray paint. After that I then have to peel every tiny pieces of the protective plastic off one at a time that take around 2.5 hours to do a 28"x18" piece. My question is, is there something that you can put over the acrylic that maybe gets melted into the etched area as you cut? Like I said I know it's a long shot but there are not many options out there to achieve the goal of my process.

I have tried to etch it without the protective plastic on and use both a acrylic paint stick and also just acrylic paint with a brush. Both have not generated quality finish on the part.

[Ross Moshinsky]

Look into plastic razor blades to remove the plastic after engraving. Also look into transfer tape instead of using the plastic sheet.

[Roy Sanders]

that plastic protective cover is toxic when melted.

[Mike Troncalli]

I don't know if this would be feasible or not, but could you run the job, paint and then do a reverse engraving to burn the paint away? I understand that it will leave the area frosted looking. But just an idea anyway..

[Scott Shepherd]

Look into plastic razor blades to remove the plastic after engraving. Also look into transfer tape instead of using the plastic sheet.

+1 on what Ross said.

[Kev Williams]

Here's the tools you need:

If you can get by with water based paint, buy Rustoleum water based paint. 'Painters Touch' works well, one of the small cans will last years...
http://www.engraver1.com/erase2/pt1.jpg

If you need enamel, buy Testors, it's one of the best paints for engraving there is.
http://www.engraver1.com/erase2/pt2.jpghttp://www.engraver1.com/erase2/pt3.jpg

For either paint, have on hand plenty of denatured alcohol.

For enamel, you'll also want some mineral spirits handy.

For water based, you'll want some Fantastik spray cleaner. ---these 3 items are for cleanup only!

For thinning, get Testors thinner for the enamel, water thins the Rustoleum.

For applying the paint: get an assortment artists painters brushes.

http://www.engraver1.com/erase2/pt6.jpg

Cheap ones work fine for this work. Smallish to about 3/4" wide is a good assortment.

Pick up some Bondo spreading brushes to use as squeegies. HD sells a 3-sized 3-pack for cheap, get a few packs.

http://www.engraver1.com/erase2/pt7.jpg

Note that you can, and may want to cut the larger ones in half, you usually won't need more than 2" wide.

For cleaning up "outside the lines": If you don't have any old ALL COTTON sheets, buy some from the thrift store, beg your relatives for their old ones, or get new ones-- just get some. Cut the sheets into square foot or larger pieces. This is probably the most important part of the paint cleaning process, the cotton sheets...

Next, you need something resembling a hard rubber sanding block.

http://www.engraver1.com/erase2/pt4.jpg



We use 1" thick plex blocks, about 2" wide and 6" long. Been going to get a couple of sanding blocks, just never have.

ALSO, and this may sound funny, but pick up some foam sanding pads.

http://www.engraver1.com/erase2/pt5.jpg



The Harbor freight ones are cheap and work fine.

Finally, keep lots of paper towels on hand.

So what to do with all this stuff:

For your first try at this, take your paint and as big a brush as you're comfy with. Start painting about an inch wide swath. Goop it on pretty good, smear it in some, until you've covered around 4 to 6" worth. -- Now take your bondo squeegie and start putty-knifing the paint into the engraving, You should get another inch or so down the line before you need more paint. Clean up the squeegie as needed, and especially when done. Don't worry about the smears, just keep them as thin as you can. Repeat this until your first inch wide swath is done. Make sure you didn't miss any spots. Go ahead and start painting another area, repeat the above.

If you used Rustoleum, then it should be dry enough within 5 minutes to try a cleanup pass. This is where it gets fun!
Take one of your sheet squares, and just using your hands (not the holding 'jaws' in the block) start near a corner and pull the sheet as tight as you can around the block. Alcohol or Fantastik works as a cleaner for the next step-- wet the top 1/3 of the sheet (I got a little much on this one ;) )

http://www.engraver1.com/erase2/pt8.jpg

and now 'block sand' the painted plex. The sheet will magically clean up the paint smears. When it stops working so good, add more cleaner to the middle third of the sheet, repeat, etc... Depending on how much area you're cleaning, you'll have to change to a dry section of sheet. When you're done, inspect, and with a piece of wetted clean sheet make a final cleanup pass.

Take some practice, but it works great!

If you're using enamel, then alcohol or mineral spirits will work, HOWEVER, use alcohol when possible as mineral spirits is pretty aggressive, it likes to loosen nearly dry enamel.

Cotton sheets are extremely absorbent, and since the fabric is dead-smooth, as long as you keep it tight, it's almost impossible for the cotton to remove paint from the engraving. For cleaning small engraved areas, just wrap some sheet tight around your finger and dob a little alky on it.

The reason for foam sanding pads, they work nearly as well as a sanding block, and they work particularly well for cleaning up round-ish items.

NOTE this works very well with painted engraving done by CUTTER TOOLS. It should work okay with laser engraved items, as long as the engraving is more than just 'superficial'. The cotton & block works well with tool engraving only .004" deep...

[Scott Shepherd]

That's quite an impressive write up, Kev. Thanks for sharing it and taking the time to write it all. I'm sure it will help many.

[Bob Davis - Sturgis SD]

Good info! Thanks for the tutorial Kev.

[adam smiz]

Wow guys thank you so much for the responses! And Kev, a special thanks for the great write up! Seeing as the magic solution doesn't seem to exist I will have to toy with all of these ideas and see what works best. If any chemists are out there please create something that can go over a already etched piece and fill in the grooves lol!

The biggest reason I keep the plastic on is because it does melt a bit into the etched area. This make a very good seal for when I spray paint. So rather then having nothing on it and having to wipe away all excess paint im getting very minimal bleed through. This also keeps the surfaces in fairly good shape as far as scratches go.

Would possible re finishing the surface sound feasible? That way I could do a quick spray of the entire piece and then polish the top to make it look perfect.

[Ross Moshinsky]

Wow guys thank you so much for the responses! And Kev, a special thanks for the great write up! Seeing as the magic solution doesn't seem to exist I will have to toy with all of these ideas and see what works best. If any chemists are out there please create something that can go over a already etched piece and fill in the grooves lol!

The biggest reason I keep the plastic on is because it does melt a bit into the etched area. This make a very good seal for when I spray paint. So rather then having nothing on it and having to wipe away all excess paint im getting very minimal bleed through. This also keeps the surfaces in fairly good shape as far as scratches go.

Would possible re finishing the surface sound feasible? That way I could do a quick spray of the entire piece and then polish the top to make it look perfect.

No. That would be a lot more work.

[Scott Shepherd]

For what you describe, I think Ross has nailed it for you. First, switch to transfer tape, not the plastic film that comes on the product, second, get plastic razor blades. The transfer tape isn't as sticky, so when you hit it with the razor blade, it pops off really easy. I did an Aztec Calendar someone created from scratch in wood a few months ago, so that has a ton of detail. I think it was about 12" x 12" worth of engraving area with 1000's of little bits and pieces. Took about 5 minutes to clean all the tape off.

In my opinion, the #1 mistake people make with color filling when using spray paints is putting too much paint down at once. Several light coats will work far better than one heavy coat when trying to do detail work like that.

One more option would be to use the acrylic paint that comes in a tube, like toothpaste. It spreads easily and it shrinks down into the piece when it dries so the paint layer isn't right at the level of the top surface.

[adam smiz]

I will have to try the transfer tape. I was told that it would most likely not seal as well and even come off once I spray paint. Will have to run some tests asap! Thanks guys

[Bert Kemp]

Would rub & Buff work for you?

[Ross Moshinsky]

I will have to try the transfer tape. I was told that it would most likely not seal as well and even come off once I spray paint. Will have to run some tests asap! Thanks guys

Transfer tape comes in about 5 different levels. Low tack up to very high tack. On a smooth surface like acrylic, medium/high tack should do the job just fine.

[Scott Shepherd]

And adding to that, transfer tape fails because of too much paint at one time.

[Joe Hillmann]

This may work.

Put a low tack transfer tape over the acrylic. Engrave through it then paint. Peel of the large pieces of transfer tape and to get the small pieces of transfer tape stick a piece of masking tape over the pieces than pull the masking tape up and a lot of the transfer tape should come up with it.