Newbie question - Can this be done ? Trying to think how you would make a 2d drawing to do this. Or maybe you would model it. I want to cut the trough (say a half circle) in the xy plane.
Thanks

I also would like to know how to cut a concave. Trying to figure out how to make a highchair tray for my grandaughter.

Just draw a series of lines to clean out the area. The distance between the lines depends on the size of the bit, and how much you want to clean up afterward. Or use a flat bottom tool to clean out most of the material, and a ballnose tool to add the radius around the edges.

im not sure what you guys want to cut?you mean like cut a half circle dish or bowl?what software you have to draw it in?the easy way to cut the highchair tray would be to pocket it out and use a form cutter,basic 2d tool path than

This sounds like something you would want to use 3Dcut to generate a tool path. same people that make vcarve..

Least that is the way I would do it.

b.

oops!

The only software I have is Alibre for modeling and 2D drawing. I want to cut a half round slot in wood, like it you took a plunge router with a round cutter and dropped it in the middle of the piece and slid it a couple of inches. The difference would be at the start and end of the cut it would be more square that round like the plunge router would do. Hope this description makes some sense.

Thanks

A slot with square corners?

Do you mean the type of slot created by a woodruff keyseat cutter? If someone knows how to create that by plunging I would love to hear the explanation also.

Edit/ If I guessed right about the woodruff style slot, can you live with some rounding of the edges? Warning: woodworking is not my thing.

Yes I think the woodruff key is what I am describing. I am attempting to attach a model I what I want to do.

Thanks

Attempting that with a 2D drawing would be extremely difficult, although it could be done with a lot of layers and a lot of calculations. Your best bet would be to export an .stl and use a 3D CAM program.

OK, thanks for the help. Guess I'll need to scrape up some new software.

MecSoft's FreeMill will import stl. And it's free.

http://www.mecsoft.com/Mec/Products/FreeMill.shtml

Then why does it install avi edit instead of free mill ??????????????

try www.cncportal.com

I just downloaded it (again) fine from the link I provided. :confused:

Then why does it install avi edit instead of free mill ??????????????

Something must be wrong with the link. It downloads freemill.exe but it installs aviedit (avi editing program). See the attached install screen.
:confused:

Create a new directory, move the install program to it. Run it from from the new directory.

The install program is messed up. It started to install a different program on my system too...

Yep, moving to another directory worked ! Man that was freakin weird ! Never seen that happen before. Makes you wonder ??

Thanks

When you get to the last step with FreeMill you must pick a post process. Which one will be best to use with Mach3 ?

generic or iso? Fanuc maybe? Not sure what choices there are.

Well for what it's worth Freemill looked pretty good until it started locking up. Reinstall does not fix problem. It worked once and that's it. Guess you get what you pay for.

You can download a demo of Meshcam at www.meshcam.com

I got Meshcam loaded. Unlike Freemill it does not lockup, however I can't seem to get it to generate the correct tool path. If someone has Meshcam could you please load the attached stl and see if it will make the tool path correctly.

I had to rename the stl to slot.txt to upload, so rename it back to slot.stl.

Thanks

It looks fine here. What kind of problem are you seeing?

The tool path does not even resemble what I want. I must be setting it up all wrong. Funny I got Freemill to make a perfect tool path before it started locking up.

It looks fine here. What kind of problem are you seeing?

When you say it looks fine do you mean the toolpath in Meshcam looks fine ? I just don't see what I could be doing that wrong in Meshcam. However I am quite capable of screwing up in a big way.:) If you can make a nc file please let me see what it looks like.

Thanks

Cut3D from vectric.com will do this no problem as long as you have a model. Check it out.

Jason

Here's a pic from MeshCAM, Mach3, and the code. There's no roughing pass, just a finish pass with a 1/4" ballnose tool.

Jason
Cut3D does work for me. Too bad it won't make the post code (demo version crippled). Worked very easily.

Thanks


Gerry
Thanks for the files. I wish I new what I was doing wrong in Meshcam. I'll try again and maybe describe how I step through the program.

Update:
I went back and did the same process except I only used a finishing pass as you said and it worked perfectly !!
:)

I got a call from Mecsoft asking about FreeMill and how it was working. I told the gut it started locking up and would not work He said to turn of (set to none) the acceleration on the display card. I tried it and it worked. No more locking up. Thought maybe someone else might want to know about this.