Thanks to @AlexRhodes and @Kentamanos I was able to start my first project using the CNC Router, it will be a ~2’x4’ sign made from 1/2" MDF.
Getting it cut out was easy and only took 15 minutes, next will be the tricky part of painting it, I’m going for a gloss black, first step will be sealing the edges with something, does anyone have a recommendation? Searching online returns a bunch of different possibilities, I’m not sure what would give the best results.
Brushing the edges with wood glue works.
It’s absolutely amazing the detail you achieved in the simulated footprints! 
I think you spend a lot more time actually preparing and finishing than actually cutting. I know for a sign I did recently it took much longer to glue 3 boards together, hand plane it and use the belt sander a bit (too big for our planer) to get it flat enough that the vacuum table would hold it securely enough to cut. Now I have to figure out a painting approach, which will probably also take longer than it did to cut.
Nice job,
The shadows really made that stand out, good photo as well.
Just ordered some Zinsser sanding sealer to try out on the mdf, will post how it goes this weekend
http://www.amazon.com/Rust-Oleum-Zinsser-854-Sealcoat-Universal/dp/B000C02BXW/ref=sr_1_1
While the sealer appeared to do a good job sealing, it is not a filler, if I were to do it again I would try using lightweight spackle instead.
On the beveled edges there is a line halfway down where the CNC router made its second pass, I thought the sealer and then primer would be enough to fill anything I couldn’t sand out but that did not turn out to be the case.
Here is it after the excessive seal coat I put on:
I sanded that down with 220 then primered it, would probably have been good to use sandable primer instead of regular to fill more
Here is an example of one of the worst part of an edge
I put on a couple more primer layers and sanded them down to try and fill more
Then wet sanded before first color coat, hopefully the few edges that didn’t end up smooth wont be too noticeable
Nice work Brandon, I so wanted to touch it the other night when the sealer was drying. If you are looking for tips on getting a perfect Plastic / Glass looking finish, try talking to @Dawsmart. He has a projector housing he made from MDF / plywood, which under close inspection looks like it was made of molded glossy plastic. It is very impressive.
Seal with shellac.
Basecoat 2-3 times with a sandable primer (water based housepaint is cheapest, sandable gesso works, or automotive spray primer if you want to spend more $ for more predicable results), sand with 150 grit.
Apply spackle (we use DAP CrackShot spackle at work, with good results). Sand with 150 grit.
2-3 more coats of sandable primer, sand to 220/320 grit.
Apply 2-4 color coats, wet sand at 400 grit between coats.
Apply 2-3 clear coats, wet sand at 600 to 1200 grit between coats.
The spackle sounds good. Or, you can use a “wood grain filler” or this product to seal the MDF edges. It’s about the consistency of mayonnaise and brushes or trowels on 
I wasn’t aware of this product. Could be good to skip steps 2 and 3 with it depending on how it works…
I decided to change the color of part of the sign, so I sanded it down and reprimered it using a filler / sandable primer, and it was able to take out all of the remaining rough spots around the edge
After first coat of clear there is some visible orange peel, not sure yet if I want to keep wet sanding or if I will consider this good enough
Next question is how to attach the piece together to the black background, initially I was thinking just 1" wood screws (would be 1 1/8" to front surface) but now I am scared that would mess up the front, so I might just glue the letters on, can anyone recommend a good glue to use for primer painted surfaces?
Wood stud screws is what I use.
just make sure you pre drill. MDF will split for sure if you don’t pre drill.
After some eyeball alignment, I liquid nailed the letters to the board, would have been better to drill holes through letters and back with CNC router and use dowels to be sure of alignment. Since I did other filling probably could get top over dowels smooth.
And finished product:
There are lots of spots that are not perfect, but after ~20 hours of painting I called it good enough. Considering I had no idea what I was doing starting out it turned out ok, another attempt would give much better results. Should have done a better job picking out colors, the blue doesn’t have enough contrast against the black background.
From initial design of:
Who says corvettes aren’t practical? Plenty of room to transport it
Also there is a 4’x4’ 1/2" MDF that is on top of the project storage shelves that anyone is free to claim, I will throw it in scrap bin next time I’m at the space.
So, silly question but, what is PTP?
I’ll take it. I have a sign I will attempt next.
It is the logo for the internal energy trading software system I work on, PowerTools Platform. This is the logo I loosely based the sign on, which has way too many gradients
So, how much to commission you to make more signs? 
There is no challenge now that I know how to make a decent sign, just a matter of time, but if someone wanted to pay me a ridiculous amount I could make more signs.
