Letter cut outs with sharp corners

This forum is for users to post tips and tricks they have found useful while working with VCarve Pro
Post Reply
chunkstyle
Posts: 33
Joined: Wed Mar 24, 2010 12:59 am

Letter cut outs with sharp corners

Post by chunkstyle »

Hi everyone,

I've searched the forums but didn't find any solutions for the problem at hand. Apologies if it's been covered already.

I'm cutting some letters out of 1.25" material. Customer asked if I could radius off the top edge of the letters with a .25" radius bit. I said sure I could (worst case scenario I would do it by hand with trim router and bit).

Question is if I could make the inside corners (like in a upper case A, for example) by using a plunging radius bit in a way that's similar to internal V carved corners?

Is this possible?

Thanks for any advice.

User avatar
Adrian
Vectric Archimage
Posts: 11805
Joined: Thu Nov 23, 2006 2:19 pm
Model of CNC Machine: ShopBot PRS Alpha 96x48
Location: Surrey, UK

Re: Letter cut outs with sharp corners

Post by Adrian »

If you want to do it on the CNC then what you need is what's called a point roundover bit which you can use with the profile toolpath.

User avatar
Leo
Vectric Wizard
Posts: 3250
Joined: Sat Jul 14, 2007 3:02 am
Model of CNC Machine: 1300 x 1300 x 254 Chinese Made
Location: East Freetown, Ma.
Contact:

Re: Letter cut outs with sharp corners

Post by Leo »

I have a picture in my head as to what you want. In my head I don't see any way possible except by hand, with a small file to blend it all in. To my knowledge there is nothing in Vectric similar to an engraving v-carve toolpath that would work with a pointy roundover bit, to make the sharp corners on a roundover inside corner. Although, THAT "would" be a really "nice to have" feature.
Imagine the Possibilities of a Creative mind

www.leosworkshop.com

chunkstyle
Posts: 33
Joined: Wed Mar 24, 2010 12:59 am

Re: Letter cut outs with sharp corners

Post by chunkstyle »

Thanks Adrian.

Yes, point roundover bit. I have one ordered and on its way. https://www.amanatool.com/56123-carbide ... 1&fp=10850

This bit makes sense for doing the plunge and rounding over on the machine but can it make a more coped inside corner appearance as opposed to a radius..?

I think that would have to work similar to how it's achieved with a V carve inside corner. The bit would retract out as it cuts the corner but, instead of a straight line path, the bit would have to follow an arc path to achieve a coped look.

Possible?

User avatar
Adrian
Vectric Archimage
Posts: 11805
Joined: Thu Nov 23, 2006 2:19 pm
Model of CNC Machine: ShopBot PRS Alpha 96x48
Location: Surrey, UK

Re: Letter cut outs with sharp corners

Post by Adrian »

Don't forget you'll have the round cutout to deal with as it's an interior cut so a roundover coming to a point would look a bit odd. You could "lie" to the software and tell it the bit is a v-bit I guess and use the Sharp Internal Corners option. It would take a bit of experimenting to get the pass depths right I expect if it would work at all.

Personally I do them on the router table with a pilot bearing tool that matches the diameter of the cutout tool as I find that to be more efficient than changing bits on the CNC.

chunkstyle
Posts: 33
Joined: Wed Mar 24, 2010 12:59 am

Re: Letter cut outs with sharp corners

Post by chunkstyle »

Thanks Adrian,

I guess getting a coped inside corner, similar to coping running trim stock, is not going to work then on the machine.

I take your point on doing secondary operations rather than the CNC. Always a question of where to do the work that makes the process go quicker.

If only the program would carve like a V bit but take a radius path coming out of the corners. That would be sweet.

User avatar
dealguy11
Vectric Wizard
Posts: 1830
Joined: Tue Sep 22, 2009 9:52 pm
Model of CNC Machine: Anderson Selexx 510
Location: Henryville, PA
Contact:

Re: Letter cut outs with sharp corners

Post by dealguy11 »

Only way I know to get a coped inside corner on something like this is with a moulding toolpath and a smallish ballnose bit.
Steve Godding
D&S Artistic Woodworking http://www.dsartisticwood.com

Post Reply