CNC Router project

[Paul Bonser]

I have a project I need to complete in the next week or two which will
require use of the big CNC router. I know it's just barely gotten up
and running, but I am hoping that this can be a bit of a test project
for it to help us learn the things that need to be taught and how to
do this particular type of project.

It's going to be a 5 foot diameter circular sign hanging at an event
during SXSW and the basic design is that it will be two layers of
plywood, one with a logo carved partway into it and another with the
same logo cut completely out of it and then inset into the first
piece.

In theory it should be a pretty simple job since it's just a 2D design
cut twice, once inside the lines and once outside the lines. There
will be a couple of places which will probably require finishing the
points with a handsaw since there are sharp corners.

Danny, what do we need to do to get started on this? I can meet you at
the space any evening this week to get going on this. I'm currently
planning on picking up the plywood from Austin Fine Lumber on Tuesday,
but would also be interested in running some smaller scale test cuts
before trying it on the full-size wood.

--
Paul Bonser | http://probablyprogramming.com | @pib

[Danny Miller]

Yeah, it's behaving better now.

Does it have to be exactly 5ft? Going all the way to exactly the 5ft
width is a bit problematic with the width of the dust shoe getting into
the rail clearances. It can do it without the shoe, but then, lotta
wood to clean up.

First off email me the design so I can play with the G-code export and
see how to make it work.

Danny

[Paul Bonser]

No, it doesn't have to be exactly 5 feet, but ideally as close as
possible. What size could we get with the dust shoe on? Something like
5.5 feet?

I've attached an Inkscape-friendly SVG of the logo that will be made
into the sign. You can see on the tree-trunk the parts that have the
sharp corners I mentioned. We could round those a little bit to make
the whole thing doable on the router, or if tool changes are an
option, we could have it do the design with a bigger bit and then
switch to a small one to finish off and make the corners a bit closer
to the pointiness intended.

> --
> You received this message because you are subscribed to the Google Groups
> "ATXHS Discuss" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to atxhs-discus...@googlegroups.com.
> To post to this group, send email to atxhs-...@googlegroups.com.
> Visit this group at http://groups.google.com/group/atxhs-discuss.
> For more options, visit https://groups.google.com/d/optout.

[Tim Fredlund]

I suspect you mean 4.5 feet with the dust shoe? : D

Tim Fredlund | @ethosrot | #tc

[Paul Bonser]

Haha, yes. That is what I meant.

[rc3105]

won't it need to be assembled from at least 4 pieces of plywood?

unless you're ordering sheets more than 4 feet wide???


-
R

[Tim Fredlund]

You can get 5x5 pieces of plywood -- part of the principle reason the active area for the table CNC is wider than 4x8.

Tim Fredlund | @ethosrot | #tc

R

[Danny Miller]

Alright are the square what stays, or goes?

Danny

[Paul Bonser]

Here's a filled version for clarity.

The black part is carved half way into the bottom layer. Then it is
cut out of the top layer and inset into the holes in the bottom layer.
So the final product will be the multiple shapes of the black portion
sticking out of a solid layer underneath.

I'll show you a 3d model of the final product as soon as I finish
extruding it in Blender in a few minutes.

[Paul Bonser]

Like so.

[Paul Bonser]

And just to be clear (and because I just spent a bunch of time re-learning how to use blender),

the top layer: 

and the bottom layer: 

I think those show the idea really well how the top pieces will nest into the bottom pieces.

[Danny Miller]

What's the thickness of plywood here?

Danny

[Danny Miller]

OK, I have toolpaths.

I used 3/4" plywood in the model and got 1hr 37min of machine time to do
the cutout sheet and the pocketed base.

Danny

[Danny Miller]

You gonna be able to transport a 5ft diameter sign??

Danny

[Paul Bonser]

Oh yeah, I didn't make the thickness of the 3D models to scale, I was
just demonstrating the general concept.

The plywood I was planning on using will be 1/2"

And yes, we'll be able to put the sign in the back of a truck at an angle.

[Paul Bonser]

Also, can we do a scaled-down test run on some 1/4" ply?

[Paul Bonser]

Danny, will you be by the space today? I'm going to pick up the plywood in a bit and I'd love to get this cut out today.

[Joseph Ngo]

Could someone please shoot video on the cut.  Thanks. Also what time if it is going to happen today?

[Danny Miller]

Probably 8PM or so.  So this is like the first time doing sheet so we're gonna be fumbling with software and holddowns and feedrates. 

I did load up your PDF and make some toolpaths that should work.

Danny

[Paul Bonser]

Sounds good! I've got the wood here at the space now and I'll be
around the space for the rest of the day.

I did get the 1/2" plywood rather than 3/4", if that makes a
difference or means we'll need to regenerate the toolpaths. Also I'd
like to try a scaled down version on some 1/4" ply first, so that
should give us an idea of how it will go with a larger sheet. Or I
guess a smaller piece of 1/2" plywood would make for a good test as
well.

[Clio Dunn]

Yes, I can be there by 8pm to shoot video. Just don't start early.  I'll be there at 8pm.