I’m feeling slightly heart-broken as my Shapeoko 3 just inexplicably gouged a big hole in the drill press table I just finished building. It’s all part of the learning process, and I’ve certainly messed up plenty of projects through user error and simple trial-and-error, but this one I have no idea why the tool path is so different from the design.
All I wanted was to drill a simple 5/8" hole 1.5" straight through a drill press table that is 2 pieces of 3/4" plywood with Formice laminate on top. The day before I had used the same technique to drill a 1/2" deep circle that is 7.5" across that perfectly holds a disposable drill press backer. But with the 5/8" inside hole, for some reason the gCode started drilling a 1.25" hole. I aborted it as quickly as I could but the damage was done.
I thought I must’ve specified outside hole instead of inside hole (although that should’ve only resulted in a 1" hole instead of 1.25" with a 1/4" bit), but the path says inside hole anyway. When I look at the simulation it appears different yet, but I don’t understand why. My canvas is simply 2" square with the origin in the top center. Again, the same technique worked perfectly to carve out the bigger pocket the day before.
No idea on what may have happened but if you DID choose outside, it would actually be 5/8 + 1/4 + 1/4
or = 1 1/8" or 1.125" total assuming a 1/4" bit properly setup. If it’s in Carbide Create you could maybe post the file and someone could look it over.
I opened the “smallhole.c2d” that @markmoran posted in Carbide Create. It shows a 1.25 in circle cut using #201 (1/4" in) inside-left to a depth of 1.5 in at 0.139 in DOC, 60 in/min feed, 30in/min plunge. The preview seems to show what you’d expect.
I think you drew your circle too big and when you looked at it on screen you noticed that the tool path is 1" across (inside your 1.25" circle) and forgot that the blue line is the center of the bit and the orange line is the circle you drew that includes the extra 1/4" (1/8" on each side) that the cutter will cut.
That really sucks!
Maybe you can put the hole in the center of that one, if it’s not too deep, and say you did it for looks, or fill it in.
I hate it when I spend a lot of time on something, and that happens. Makes me want to beat my head on a tree;)
At least you know now that the software works OK, just a mis sight.
Thats a really nice looking table, I hope you can fix it.
Thank you, Mark! (And Will & Roger too). I’ve had so much success with the SO3 from both Carbide Create and Fusion that I got sloppy and forgot to look at the preview and test either above the material or in a scrap piece, all of which I used to do. Argh!
I am simply an idiot. I wanted a circle with a .625" diameter but the parameter that Carbide Create is asking for is radius.
So correctly my circle is twice as big as I wanted. Since my canvas was so small (2" square) I didn’t even notice that the circle seemed way too large for the space. I was thrown off checking afterword that the preview did not show the circle in the center of the material the way it is in the diagram, but I guess the preview window has a minimum size of the canvas?
It’s a bummer that I F’d this up when I was all done with the table and was even on the fence about whether to add these small holes to hang on the wall occasionally. I even thought about just doing them on the drill press itself, but figured the router would definitely not crack the laminate.
It probably wouldn’t have helped in this case but Camotics is a free simulation program that you can test your G Code in if you ever want a “second opinion” besides Carbide Create.
Must be catchy. I just finished a 16" wide V carved picture, was doing the cut out, and it ran right across the bottom into my clamps.
It’s pretty strong
It ripped the first clamp, and insert out, and moved the other out of the way, and broke a v wheel.
Sooo, I just bought the maintenance kit.
The other funny thing is, I just moved my clamps so they wouldn’t be in the way.
The picture was salvageable tho.
Thanks, Kurt. I’ve used Camotics before, but again, got so over-confident that I didn’t even bother looking at the simulation in Carbide Create until after I screwed up.
