[kbillan]

Greetings all.

I bought a taig mill, meshcam, mach3, rhino.. the whole deal... i drew up my part, and i exported it from the 3dm file from rhino to a dxf file.. for meshcam.. well, when i try to open it, it says that the drawing was not created from polygons- or something to that effect...

can someone tell me what i did wrong? What i have to do? The drawing is exactly what it should be as far as dimensions go.. and i have used surface patch to make surfaces.. and everything.. the thing renders nicely.. I just cant bring it into meshcam..

assistance would be SUPER appreciated...

keith

[ger21]

From Rhino, you should export as an .stl file. If you don't know exactly what you're doing, .dxf import into MeshCAM can be tricky. .stl's shjould be much easier to use.

[kbillan]

Why thank you! Your quick reply is super appreciated.

It worked= sort of. I now have the main object in meshcam, but am missing some parts of the drawing that tied surfaces together.. hard to explain really.. but ill try..

Better yet, ill attach a pic of what i drew...

the black part of this buckle, is the base layer of my drawing. I turn on other layers and the gold ring and dials appear, then the outer buckle.

i want to generate toolpaths for the black part so I saved it as a different file, deleted the rest and imported it. But the file in meshcam is not showing any of the angled steps (theres 2 of them around the center rings)

[robgrz]

I'm going from memory here but I believe you have two options in Rhino- you can save the file as STL or you can select the objects you want and export only them. Which are you doing?

-Robert

[kbillan]

I'm going from memory here but I believe you have two options in Rhino- you can save the file as STL or you can select the objects you want and export only them. Which are you doing?

-Robert

I took this to your forum-- but ill answer here as well.

I took all of the stuff out that i wasnt working with.. IE, the stuff that is not done.. I then save the file, as a .stl and then tried to open it with Meshcam.. which it opened fine. But, like i said- the angles in the steps did not come for the ride...

[ger21]

Sounds like you're doing something in Rhino that doesn't export. Perhaps a different modeling method?

[robgrz]

FYI- Kieth sent me his file and Rhino V4 seemed to export everything cleanly. I was able to open the resulting file in MeshCAM and it came in OK.

I used an STL tolerance of .001 in Rhino but I don't think it would cause parts of the model to be excluded if a different value was used.

-Robert

[kbillan]

Yes, it has all been cleared up. being a new guy i have a lot to learn.

I am now cutting parts quite well. Thank you Robert..


My next question is regarding tool paths and tool clearances.. It seems like the software should compensate for tool diameters when writing the code. But while cutting parts- there will be sections that get marred up because the endmill (.062 ball) bumps into the part, at the shaft.

How do i compensate for this?

for this tool- as an example.. how would you enter this into all of the fields in meshcam?

http://www.bitsbits.net/index.php?ma...products_id=70


Keith

[robgrz]

When defining the tool, set the shaft diameter to the correct value, 1/8" in the one you linked to, and the flute diameter to the cutting length of the mill. This should solve the problem but, because of the tool geometry, areas of the part will not be fully machined.

-Robert

[kbillan]

When defining the tool, set the shaft diameter to the correct value, 1/8" in the one you linked to, and the flute diameter to the cutting length of the mill. This should solve the problem but, because of the tool geometry, areas of the part will not be fully machined.

-Robert

cutting length of the mill? what does this mean? I am taking this as the length of the cutting surface on the end mill. But in the case of this tool, it has a taper... and that is where it is messing up.

You say it will only be partially machined.. how to compensate? I have other end mills- will pencil finish accommodate this? or will writing a whole other code and just saving the finishing path work? or would it be more beneficial to run the part with a smaller bit?

I would think the program would cut the verticals with the larger bit i am roughing with.. and then cut around that...

there has to be a better way. awful lot invested to settle for this.. and I am not doing anything PRECISE.. im pretty easy to please.. and i know that this machine is capable of doing things precisely..


Keith

[robgrz]

Set the flute lenget to the length of the mill at the start of the taper- treat the taper as part of the shaft.

The only way around the unmachined problem is to find a mill (the bit, not the Sherline) with a longer flute length. These are tough to find, expensive, and fragile- other than that, no problems. Whenever possible I prefer a tapered ball mill. They have the best strength and give pretty good accessibility. They are tough to find in small sizes and the are even more expensive. They are more durable so they tend to last longer for me.

I would look around at jeweler forums as well- they use small versions of this a lot.

-Robert