Engraving aluminum......

[Tyler Durden]

Anyone know how they are able to paint the engraved designs in aluminum? I have seen this, but do not know how it is done. Example: Custom valve covers are easily milled with a design with cad/cam, but a few sites I have seen on the web show these designs on the valve covers painted different colors. It's easy to engrave a design on aluminum that is anodized, then you have a silver design with an anodiozed background. What I want is when the design is milled, I can paint over this......then peel off a coating from over spray. Is there some kind of non-permanent adhesive you can put over stuff like this and mill the design and paint ONLY what you mill? Then remove the adhesive to have the rest of the polished aluminum not ruined from the overspray?

I hope I explained this right. Hard to explain something you have no idea if they make anything like this

[SCROMAL]

Tyler
Try avery paint mask I think that will work

Steve

[snakebit95]

I would be interested in finding something that works too. I have tried all of the different masking tapes, including the highest strength adhesives. Basically, I applied the tape to the part prior to machining. The biggest problem is the tape pulling-up on the edges or tearing while machining the part. It may only lift a tiny bit around some lettering, but that is enough for the paint to migrate to an area that you do not want it to. I was using brand new carbide cutters too.

[Apples]

just an idea but could you melt a candle above it. The wya goes hard. Machine throught that. Smear the rest in grease so that the paint will not stick. They after machining. Spraypaint. Let it dry,. Then wipe of all the grease and wax. This should leave the paint in the machined part, maybe!!!

Just scratching my head having a quick think.

Cheers
Peter
Australia

[DareBee]

I generally mill and paint these details before polishing/ annodizing. The paint can then be polished off and the detail can be masked/waxed for the main finishing process.

It is possible that I am not completely understanding your situation.

[Tyler Durden]

Originally Posted by DareBee I generally mill and paint these details before polishing/ annodizing. The paint can then be polished off and the detail can be masked/waxed for the main finishing process. It is possible that I am not completely understanding your situation.

The only reason I would get something anodized, is so that when I mill my design in the aluminum, the milled design shows up another color(silver) from the endmill taking off the color of anodize.

I'm interested on how you anodize or paint the milled design first. This is what I want to do, but don't know how you can paint the milled design with overspray ruining the rest of the part. I don't understand how you mask it off or use wax. Any kind of wax? Do you mill into the wax, then paint into the wax that is milled off and have the rest of the wax to prevent overspray? How do you polish it off, and what do you use to polish the paint off?

Right now, the only way I know how to make a design another color is to use an anodized part, then mill into it to make it show up. I'm a total noob, so if you could explain in detail like I'm an idiot that I am, that would help lol.

[SeaSchell]

Send it to Me! I will mill as an emboss and paint whatever color you want

[One of Many]

I made some custom billet GMC hub centers for my pickup a few years back.

It took some trials to get the professional look I was after.

I milled the logo, masked the top surface and used an exacto knife to trim out the logo using the milled top edge as my guide to trim the masking fuzz free.

Once prep'd and painted I found out the trick for a crisp , but clean beveled paint edge, was to remove the masking before the paint starts to set. Letting the paint tack before removing the masking would leave strings and tears along the edge. Letting it dry leaves a rough chipped edge. Another benefit if the paint is still wet is that very small touchups with a brush are still possible and blend well.

Preparing small surfaces like the triangle inside an A on other projects I have had decent luck with, was to leave a flag of tape sticking up about the features centerline.

I have seen grease useda and tried it, but if any residue gets on the prepainted surfaces, the paint won't stay. The paint must be dry before the part can be cleaned and some paints don't do well with solvents that desolve grease without ruining the paint.

It may take a few trials for anyone to come up with what works. Experience should teach you what to do or not do the next time.

DC

[SRT Mike]

two ways to do it I can think of other than what's been mentioned.

If the surface is flat, then the milled part will be lower. You can spray the whole thing then take a flat sanding block with some fine sandpaper and it will sand away all the paint other than the recessed areas.

Second way is to use a toothpick and dip it in the paint and blot it into the engraved area (this works well for highly detailed parts).

Only other thing I can think of is to use some kind of easily removable adhesive - mill through it, paint, then remove the adhesive (like you said). I'd consider trying something like nail polish, or maybe elmers glue. If you get paint that won't be taken off by acetone, the nail polish would work great - just wipe it off when you're done.

[snowshovelbmx]

I have done this before and the method that I used was to machine the part, and then spray paint the entire area, after the paint dries use some sand paper on a flat surface and rub the part over the sand paper, use a finer grit so that it will not leave too deep of scratches, and then just polish the part after all of the paint is gone, wipe dry and voila. make sure that the engraving is deep enough that the paint will not be removed during the buffing process.

[Torchhead]

Or....(for something completely different) use the method the sandcarvers use for glass etching: Cut the stencil/mask in sandblast resist uisng a vinyl cutter. Paint/anodize your base coat first. Mask everything you want protected and weed out the cut design on the sandblast mask. For light sandblasting you can get by with Paint resist grade vinyl. Sandblast the design into the base color/metal as deep as you want. With the mask still in place spray the color you want on the design. Peal and marvel!

While they do this on glass and leave the base as clear and the fill as a metallic, the same approach works.

[snowshovelbmx]

They also use that same technique for making tombstones(my friend used to own a monument company) I wonder if you could use the rubber mat and machine through the rubber and the aluminum and then paint with the rubber still on, either way I think there are quite a few different ways of doing this.