[Trotline]

So, I cut quite a few celtic crosses. They're visually interesting, and people like them. I've probably sold more of those than any other thing I've done with my machine. Ever since I started Vcarving them, I've wanted to model them in 2.5D, and not long ago, I decided to go ahead and do it.

First, I did it using Embossing, in BobArt. It went pretty well, and the end result was a usable surface. Then I found out that I couldn't manipulate (scale or rotate) a BobArt surface. I have no idea how I went this long without knowing that. I've done a ton of embossing..

Attachment 181343

>.<

OK, back to the drawing board. Embossing was out, so it was time to get cozy with the solid modeling toolbox. Once I got everything done, I actually managed to get every one of these added and stitched into a single solid, but my computer just about has a cow when I try to do anything with that one. It will handle the whole pile as separate solids, though. I just have to be careful to always select everything when I do something to it.

I cut the first part today, and it came out really well. The sun had set by the time it was done, and I have a pretty lame camera, so I'll post a picture of that tomorrow. Total cutting time was a little over 4 hours, for a part 9.3" tall, and 6" wide. This is one of those times I'm happy to be done with a job. Both of those were time consuming and fiddly. I probably won't cut many of these, but it'll be nice to have a "Cadillac" version if someone wants to be a big spender.

Attachment 181342

Luke

[BurrMan]

Then I found out that I couldn't manipulate (scale or rotate) a BobArt surface. I have no idea how I went this long without knowing that. I've done a ton of embossing..
Luke

Did you know that you can save your BobArt Emboss surface out as an STL and reload it?

Also, Many parts of the pine tree are edible and grape nuts remind yule of wild hickory nuts.

[Trotline]

Yeah, I did save the emboss out as an .stl, and that does allow for some manipulation. You got me to remembering more about why I decided to try the solid model route now. All of the interlaced elements are done with 2-rail sweeps, and the ones in the corners, with the sharp bends, always looked funky, no matter how I played with the settings. That was the reason I tried a different tack, but I'd forgotten.

As it turns out, I ended up having to divide those elements into two solids to make it work right, and if I'd tried that with the emboss, it might well have fixed the problem I ran into. Just goes to show, there's generally more than 1 way to approach a problem, in CAD/CAM. Say, Burrman, I passed along your method of manually adding tabs on another forum the other day. It was much appreciated. I credited you, and linked the video you posted here a while back.

Mmm, pine nuts..

Luke

[jrmach]

Would like to see the pics.Time Killer,huh?

[Trotline]

Yeah, I really don't want to know how much time actually went into the two different ones. I'm kinda learning as I go, so it's concentrated up front in both cases. Figuring out what methods would get the results I wanted took some experimentation. Then it was mostly about doing the same sorts of operations a lot of times, getting better and faster at it as I went.

One thing's for certain. I designed my machine on a few sheets of graph paper late last summer. At the time, I didn't have any sort of CAD software, and wouldn't have known how to use it if I did. I've come a long way since then, even if I still have a long way yet to go.

Luke

[BurrMan]

Awsome solids Trotline........

[victorofga]

i have only version 22.. as much i remmeber didnt imported svg or eps..

inkscape import eps and can output bsplines in dxf.. so no more million little straigth lines from eps to dxf..
all node is ""ON"" type..

for celtic knots theres a free program made by steven abbots

http://www.stevenabbott.co.uk/Knots/knots.html

it makes true vaweing.. can save in obj format you migth convert with accutrans to dxf

[victorofga]

it has both an stl and a dxf file about a heart made of knots..
with accutrans stls can be converted to dxf..
if stl too large the free netfabb can slice up to parts, and parts can be converted to dxf so it can be editable..

[Trotline]

Here's the piece about halfway through finish sanding, next to a Vcarved one about the same size. Same .dxf "bones" for both of them, although I did some wholesale editing and optimization as I went through the process of converting to solids.

Attachment 181403Attachment 181404

Luke

[Trotline]

And here after a coat of Watco danish oil.

Attachment 181421

Luke

[jrmach]

Pretty Cool Luke.You use Slice Planar on the new one?What size tool and step-over?

[Trotline]

Yep, Slice Planar toolpaths, I did a roughing pass with a 1/8" ballnose at 0.05" stepover, then came back with a 1/16" ballnose and 0.005" stepover. I rarely use the 1/16" ballnose, but this time there were all those little corners to get into and define, so it more than paid for itself.

Luke

[Cloud rider]

Wow. I have a long ways to go before being able to do that. Great work. Thanks for sharing the pics.

Ronnie

[jcarpenter2]

Well Trotline i know this is any older thread, but after seeing your videos i had to give this a try. Im still new to cnc so your videos were great to watch. Mine didnt turn out as well. I still need to figure out why mine isnt doing the circular arcs right.

[jrmach]

upload your file and let us look

[Trotline]

Jcarpenter2, I'm glad you started looking at the capabilities of BobCAD's decorative toolkit, and I'm especially glad I could help you get started on it. I'm just about certain that your problem with the arcs is a Tolerance setting that's too high. Here's a screenshot of the settings I run. Under <Settings> [Part], and the same ones under <Settings> [Default]. I cranked these numbers way up, and simulated that file, getting results that looked exactly like what you see in your cut. If you'll trim these tolerances down, and regenerate your toolpaths, I believe you'll be pleased with the results.

Luke

[Trotline]

Dang it, I goofed when I reset my tolerances and the first screenshot is not what I actually use. Here's the correct numbers. Sorry. Set those as your Defaults, and they'll automatically apply to new parts, but for purposes of this part, you'll have to change the Part settings, then regenerate your toolpaths to get the desired effect.


Luke

[umairashraf]

NEED HELP....!!!!!!
I am new to CNC manufacturing working with catia...i want to know how to open and edit post processor and how to link catia with mach 3..
please some one reply

[jrmach]

NEED HELP....!!!!!!
I am new to CNC manufacturing working with catia...i want to know how to open and edit post processor and how to link catia with mach 3..
please some one reply

you are in the wrong Forum

[jcarpenter2]

I must have a different version than you, mine is v24 and in my system settings i only have a tolerance box with "system" and "chain select" and they are set at .0001 and .0010 respectively.

Dang it, I goofed when I reset my tolerances and the first screenshot is not what I actually use. Here's the correct numbers. Sorry. Set those as your Defaults, and they'll automatically apply to new parts, but for purposes of this part, you'll have to change the Part settings, then regenerate your toolpaths to get the desired effect.


Luke