creating an accurate trough

[brian]

I've been asked to make a 1.5 dia trough for a flute.It starts out with two 1 inch peaces of wood that will both have a 1.5 wide by .75 deep trough.When glued together it makes a 1.5" radius bore
He wants it fairly accurate.
I've used the shape editor to try to get what I want so far I've been able to get the 1.5" wide I need but the accurate depth is the issue.So far either it's been to shallow or way to deep

Brian

[Brady Watson]

Just draw a 1.5" circle, using node editing mode (N key) and remove the 2 upper arcs. You'll have a perfect shape.

-B

[garyb]

As Brady said node edit your 1.5" circle for a profile, then do a two rail sweep
Gary

[harold_weber]

If you are going to make more than a few of these parts, I'd buy the Whiteside #1415 corebox bit (which is a 3/4 radius) and create a toolpath that simply has a few depth passes and one light final cleanup pass. The cutting will go much faster (there will be no stepover, just stepdown). Hope that's clear - coffee's not ready yet.

[Gary Campbell]

Brian...
Agree with Brady & Gary on the 2 rail sweep. Cut 2 pieces of material together as per Gary's picture, then assemble.

Cant see how Harold's method will work. Using a 3/4 radius tool can possibly reduce stepover of 1 1/2" radius cut path, but not eliminate multiple paths to get final cut.

[harold_weber]

OH,,,,,,,,,,,,,,,,, now that I've had some coffee, I see he wants a 1.5 inch radius circle, I thought I read 1.5 inch diameter. Sorry.

[Gary Campbell]

I KNEW it was a coffee problem! :D

[MogulTx]

I have heard of this "Two rail sweep" a couple of times on this forum. I need to look through the help files and see what I can learn about that. I think it will be the next big tool in my skills kit ... it sounds like it will add some great capabilities.

[gc3]

http://www.vectric.com/forum/viewtopic.php?f=28&t=4749

here is a good and quick tut on a sweep

[brian]

Thanks for the quick responses.
I didn't think the two rail sweep would work for this.


Thanks again

[knight_toolworks]

no need for a two rail sweep. just draw it up with the right width and ends
choose create shape and choose circle and make it negative 90 and it will be right if you don't limit height.

[MogulTx]

Thanks Gene! I appreciate it!

Monty

[brian]

I initially used the shape editor and was having problems with an accurate depth.I created an 90deg arc in shape editor but the depth was too deep.If you limited or set the depth it would flatten the bottom of the radius and make it too shallow.
I found the two rail sweep works but leaves a rounded lip.I dont know if this is due to improper Z depth setting or if it's normal with a 3d profile.
I still playing with it.It's only off by .01 but I'd like to get it more accurate if possible.
This makes me feel like a bit of a dunce(why do I hear my wifes voice in my head :) )
I'm going to due some random depth tests with the Z axis today to see if that's where the problem is


Brian

[bleeth]

It must be 1 1/2" D since the block is only 1" thick.

If you do your vectors right there is no "rounded" edge.
After drawing my lines and a halved circle the right size I used the same half circle by copying and pasting to make the ends and then cut them and joined to get a clean top and bottom rail with no gaps. You could shortcut this by drawing a rectangle with .75" radius corners and then cutting the vector in node editor to get 2 matching vectors. Make both start points at the same end after you split it.

Attached is a shot of my quick model.

BTW : I use ACPro but it works just the same in Aspire