Hi all, I want to check my plan with the great minds here. I am creating a sign, 10" by 20". I am using 3/4 in plywood and want to carve a recess to pour the epoxy, which I will then carve and fill with more different color epoxy for the design and lettering.
The recess being 10x20 inches; so to carve that I am going 1/2 inch deep. I am going around the outside with a 1/8 bit to get sharp corners,then - and here is where I need help or confirmation - coming back in with a surfacing bit to carve out the bulk of the interior. I plan to use a spoilboard surfacing bit, but even with that CC is telling me it will be a four (4) hour job.
Do I just grit my teeth and hit ‘run’ or is there a better way?
Because the recommended speeds and feeds tend to be pretty safe/conservative I would start by reserving a small amount of plywood, maybe a couple 6x6" blanks, and then doing some tests to see how hard you can push a cutter. A good 1/4" cutter could probably be pushed up to 80-100 IPM between 1/8" and 1/4" deep per pass, which would cut that time in half or more compared to the Carbide Create defaults. Finding out the safe limits for your exact use case will save you the most time.
Also, because wood, even plywood, will warp a little if you remove a lot of material from a body, you may find it easier, faster, and better to buy half inch plywood, cut out the shape of the pocket you need, and then glue that to another piece of 1/2" plywood. No need to shred all that material inside that cavity you’re trying to make, and you could even save the scraps for something else.