Best sandpaper for etched pedals?

[WhiskeyMadeMeDoIt]

 I am attempting another reverse etch and I'm having problems with the grit fouling the paint. Any suggestions on sandpaper types , best grit, technique to avoid this. I have experimented with a few different paints and curing times. Nothing is working so far.

[davent]

What are you backing the paper with when you're sanding, i presume after you've etched and then painted. I'd think for best results you'd need something like a smooth flat piece of wood.

[thelonious]

Are you using wet/dry sandpaper? Re Dave's suggestion about the wood block---I use a hard rubber sanding block. I sand under running water with 400 & 600 grit, then dry with lint-free cloth, then use acetone to clean all the grit off before painting. Make sure it's super dry, too---use a heat gun or let it dry for a long time before painting.

[WhiskeyMadeMeDoIt]

Yes Dave after etching and then painting. I am using a flat surface and sanding back the paint from the raised edges. It seems the paint gets a nasty grime in places that I can't wipe off with a cloth.  I end up using a touch of thinned down acetone and it still looks bad. This is for a reverse etch with large painted areas and a few raised edges.  I have been using a black sandpaper and I just went and bought some 3m pro paper. I'll see if this fixes the problem.  I am welcome to suggestions. This is my third attempt on this design and it has been a pain. Never had issues before but I usually have more edges and less paint

[poppyman]

I had the same issues when I started etching boxes.
Something I found really helpful to avoid the black grime on your paint is to sand with a block and soft sand paper (400/600) under running warm water. I usually had a drop of dish washing liquid so it goes even smoother. I also double check how it goes very often to see if I don't oversand the paint because if your etch isn't too deep, it's easy to over do the sanding phase. Hope it helps.

[WhiskeyMadeMeDoIt]

Thanks poppyman. I will give that a go and let you know how it worked out.  First I am going to let this paint fully cure before attempting any sanding.  

[WhiskeyMadeMeDoIt]

The 3m Pro Grade worked perfectly.  It did not create that nasty grit i usually get from the other paper and the aluminum and paint where easy to blow away after every few strokes . No loading and no funk on the box! It was costly but worth every penny. The sandpaper is purple if anyone is looking for it.

[escapeplan]

I have the good fortune to work right by the Klingspor woodworking shop, so I get boxes of their 320 and 180 wet / dry. I use a spray bottle and a bit of dish soap, and when I notice the top getting too pasty, I rinse under warm water. Clean with acetone prior to transfer, then use a piece of marble threshold and 180 grit to sand back after etching and painting. The Klingspor paper works great for me, and a rougher grit on a flat hard surface to sand back after paint cures helps avoid issues with sanding into the design. Even with fine lines, I've had great results. This was a really rough looking enclosure before the etch...

[deadastronaut]

i use 180 at first...with warm soapy water..(this 'keys' it and cleans it too)

then i iron...(use nail varnish for edges, and check under a light source for tiny dots of silver coming through where toner may have missed , dab them with nail varnish)

etch in warm ferric.

then straight out of ferric under running tap with a toothbrush to get dead burnt metal out..

and sand off toner/nail varnish with 400/600...by the time youve got all the toner/varnish off your paper has become more like 1200

so you get a semi/polished finish as a bonus..

paint....sand again (with dead 600 or new 1200 , even more buffed...thats my process. sorted.

[bluebunny]

Ya big show-off, Rob!

Gorgeous,* of course.  But still a big show-off!   




---
* The etch, not you... 

[deadastronaut]

yeah i am...

show off, show off, pick your nose and blow off...