Keyhole and undercuts with carbide create

[jsnmdad (Wayne Snyder)]

Can anyone help me make keyholes with Carbide Create? Not just a keyhole but a keyhole with an undercut, so I can hang it on a screw in the wall.
Here is my process so far:

1. Use and end mill to cut the keyhole shape (pocket), without undercut.
2. Change to the keyhole bit (bit with undercut).
3. Plunge the bit to the bottom of the pocket (below the surface) and contour cut up to the end. But then carbide create would extract the tool vertically and ruin the keyhole.
4. So, I think I have to edit the G-code to back the tool out the same hole it came it.
   Any better ideas are appreciated!
   Wayne

[WillAdams (William Adams (Carbide 3D))]

There’s a toolpath for that:

For more on this see:

Using a keyhole tool

This came up in a support e-mail — unfortunately, Carbide Create can’t preview this, but it can be done — it just takes a bit of faith: ​ ​First, model the slot (the width should be a bit more than the shaft of the keyhole tool, the length equal to how long you want) — this is best done as two circles and a rectangle all connected — using a rectangle makes it easy to position the circles since one can use the midpoints: [image] ​Then draw in the entry hole (this should be a bit more in dia…

Undercuts can’t be modeled, so one has to take them on a bit of faith as shown in/discussed at:

Sharing Carbide Create Dovetail Files

Hi All I am new to this entire process. Have anyone created any dovetail joints using Carbide Create? If you have can you please upload a your carbide create file. Thanks in advance

[gdon_2003 (Guy Donham)]

I use a Frued keyhole bit to make key holes. The tool path plunges to the depth and then plows forward to cut the narrower part of the keyhole. Since the bottom cutter is wider than the stem you get a recess that the screw head can fit in. Here is an example on a plaque I just finished.

Here is my custom tool for the Frued Keyhole bit. Do not use my tool unless you have exactly the same model keyhole bit. Use my database as a guide for a keyhole bit you may have.

number	vendor	model	URL	name	type	diameter	cornerradius	flutelength	shaftdiameter	angle	numflutes	stickout	coating	metric	notes	machine	material	plungerate	feedrate	rpm	depth	cutpower	finishallowance	3dstepover	3dfeedrate	3drpm
701	Freud	70-104		701 Keyhole	end	0.39	0	0.25	0	0	2	0.125		0				8	40	16000	0.4375		1	1	60	16000

I need to slow the IPM after the bit plunges because my router really screams when it moves forward. I just dont make a lot of keyholes and forget to do it.

Edit: I shamed myself to updating the F&S for the Keyhole. Should have done this a long time ago. The keyhole tool path is very fast so slowing things down wont effect my cutting time much.

number	vendor	model	URL	name	type	diameter	cornerradius	flutelength	shaftdiameter	angle	numflutes	stickout	coating	metric	notes	machine	material	plungerate	feedrate	rpm	depth	cutpower	finishallowance	3dstepover	3dfeedrate	3drpm
701	Freud	70-104		701 Keyhole	end	0.39	0	0.25	0	0	2	0.125		0				6	20	16000	0.4375		1	1	20	16000

[jsnmdad (Wayne Snyder)]

THANKS for the insight and experience. I was thinking of something the same but it’s nice to know someone else has done it.
Can you share your tool library?
Thanks again, Wayne

[gdon_2003 (Guy Donham)]

I included the .csv file above.

here is the actual file. The forum did not like the extension so here it is on google drive. Just click link and you can download.

Guy-Hardwood-Keyhole+Shapeoko 3+Hardwood.csv