CNC Build – And that’s how we do that.

Today, I decided that I was ready to start making some sawdust again. I had gathered and sorted all my endmills last night, and I found the one that had tried to kill me all those years ago. By the way, if anyone reading this knows a good way to clean endmills, I’d like to hear about it. I remember when I was cutting out the parts for the Big Machine, I’d have to swap in new cutters almost every new piece of ply, because the glue gets gummed in the teeth. The cutters are still sharp, but they can’t reach the wood anymore. Probably the lower speeds of the SuperPID will help a bit, but I have some really nice bits that just need to be de-glued. I digress.

I started with the speed-n-feed test. I ran it on MDF once and on dimensional lumber once. In both cuts, it seems like 15k RPM made a pretty clean cut. The 100ipm feedrate looked like it would work, too.

It was around this point where my wife turned up, and I allowed as to how I was going to start in on the Pumpkin I owed her, and she said that what she really wanted first, was a new set of house numbers, for the sign at the end of the driveway. We have a lot of problems with packages getting delivered to our neighbors, and although there’s a sign already, it would be helpful if it was a little larger.

We had scrounged some free wood when a local farm set out a bunch of scrap, and we’d earmarked a couple pieces for the CNC specifically, so that’s what I used. It is some really cool old lumber, rough sawn 1x12s. I guessed that 6″ high digits should be visible a long way off, so then it was a simple matter of choosing a font and we were off!

With a couple of rounds of “which one do you like better”, K helped me to pick out the one she wanted. I found that my CamBam skills are a little rusty, but it came back pretty quickly.

I set the tool up, did a full “air cut” to make sure I understood what was going on, and then set the machine to cut its first “real” project in years and years. I think it turned out rather well.

I love the smell of sawdust in the morning.

I chopped the board to size in the tablesaw (I swear it’s easier to set up than the chopsaw), deployed it to the end of the driveway, and started thinking about what’s next.

As an aside, the Dust Deputy / vacuum shoe worked like a charm. There was a faint smell of sawdust as the machine ran, but nothing on the table or in the cuts or in the air, to speak of. Nice!

For the next trick, I decided to take on a new sign for the observatory; the “Hilltop” sign it’s been sporting for the past couple years was actually the first thing I ever cut on the Big CNC (it’s pretty easy to do text, don’t even need a CAD program, just do it all in CamBam), and it’s cool and everything, but it was cut on a nasty piece of scrap wood, so I’d been looking forward to replacing it.

I considered just cutting the same design as before; I’d picked the font because it has rounded serifs (which work well with router cutting), but I ended up re-creating the project, because I wanted it to say “Hilltop Observatory” instead of, simply, “Hilltop”. I looked at a bunch of fonts, and landed on one that I thought might look cool with rounded serifs. My first attempt to cut the project went sideways, because I hadn’t set the cut depth deep enough, and the board is decidedly not flat. When I tried to re-cut to the new depth (in the same spot), that failed (pretty much as suspected), because I had forgotten to “Ref All Home” in between attempts, and the machine is not quite tuned enough to be repeatable, yet. Note to self: remember to re-home the machine! I wonder if there’s a way to do that in G-Code? hmm…

Anyway, so I ruined a chunk of 1×12, but there was still more than enough left to cut the sign out in a different spot. This time, the cut depth was fine, and the job ran without a hitch.

I built the tool that built the tool that made this sign.

So. The machine works, it cuts big projects without killing anyone, and I even have some ideas about what to cut next. I do need to fix the Z transmission nut bracket. I may make one out of metal instead of wood, though, in which case it’s not the CNC that will be cutting it.
I do still owe my wife a pumpkin, which I think she’ll love, once it’s done. I have some rings to cut for Trixie, a door sign for my daughter… We are into “what project are we going to cut” and (with the exception of a short todo list) out of the “build punch list”.

These posts get to officially change from “CNC Build” to just “CNC” from now on.