Granite Engraving tool serach

[student1616]

Hello all,
I know this type of post is not new here.i red all the 16pages from this section but couldn't find the answer i was looking for.

after going thru he required pages,i think granite is the worst job to engrave on CNC.keeping this in mind i did some more search and ended up here.
http://www.incimar.com/download.aspx

its cutting granite like butter.they provided all of the tool data,imean tool types and cutting angles,except tool material.
i wonder,such cutting is possible with Carbide? i don't see any diamond tips in the image.it just look like pain carbide tool.then how come its working for them and not working for rest of the people.
and it gave me goose bumps when i saw dry cutting

[Litografa]

Do you speak about tool FOR ENGRAVING or FOR MILLING? On link you provide is milling.

[student1616]

if the machine can mill so good then iam sure it will be able to do engraving much better.
iam concerned abt the tool which can carry out such operation.
i know the engrave tool won't be same.

[Litografa]

Not agree with you. Engraving and milling FOR STONE are absolutely different technologies.
Engraving like here (BE CAREFUL 5 Mb!!!!)
http://www.litografa.lt/picture/uplo...%20mid.pdf
was done with needle (on attachment). Needle could be from Tungsteen steel (resharpable, quality of engraving decrease with each portrait, cheap) OR with synthetic/real diamond endcap ( expensive, hard to resharp, excellent longlasting quality).

May be you can see small diamond insert on picture.

Milling like on your link was done with bits (second attachment). In my life I saw ONLY diamond bits and milling always is with water.

[student1616]

thanks.
actually my requirement is,head stones made from granite.
usually lettering will be the most of the work.
but some times i might need to engrave small images along with letters.

iam building the machine my self using linear guides and 1000W high speed spindle.

[student1616]

excellent,amazing
i post the response with out looking at the PDF you posted.

my idea is something like that only.but not like the work from pdf.
its so complicated and detail.
but i must say,its the real work.

so is it done by using diamond engraving (the first image you posted) or the milling tool (2nd image)

[Litografa]

Images were done witn diamond needle (which is on right on first picture).
May be for lettering is better use sandblasting. Of course if you don't need real 3D. For real 3D CNC is vital but be ready that work will take REALLY long time Some of my customer decide DO NOT purchase CNC equipment as manually workers do 3D works faster.

[student1616]

Thanks for the info.
can you educated me little bit more regarding the tooling.
the diamond tool looks like the one people use to cut glass with.is it so.
and iam not able to see,is the tool tip at which the diamond is placed,has some angle or its just sharp conical tip?
and does the tool rotate in an spindle or it vibrates?
whats the recommended speeds and feeds for that.
and any source from where i can get one.

Thanks once again for the help

[Litografa]

Generally speaking our engraving needle and glass cutting tool are very similar. Both designed as metal holder with 0,05-0,07 carat diamond (for needle), and slightly bigger diamond 0,08-0,12 for glass cutting tool. Difference is in motion direction - for needle is hammer type motion DOWN-UP. For glass cutting tool is linear motion.

Milling tool for stone is very similar to any other milling working tool - for wood, PVC and etc. Difference is that working surface of milling bit is covered with diamonds which are 0,01-0,02 carat. They specially fixed on metal holder.

There is two ways of fixing diamond on metal
Image 1 - baking (not sure that this is right word but you will understand) - expensive but better.
Image 2 - spraying - cheaper

For DIY CNC - we also produce combined equipment with two heads - engraving and milling. In our equipment we use 1,2 - 1,5 kWt spindle with 11 000 - 25 000 rpm. Really universal equipment take may be 3-5% of our sales. Rest - only engravers. Reason - as I told you before - very slow speed of milling for all stones, except marble.

[student1616]

Thanks.once again.
i tried one yesterday.but the grid on the tool was very fine and i was running it at 10K rpm.it got blunt too fast.
i will try to make 2 new tools as you said.one with single diamond tip for engraving granite, fitted in indenting type vibrating dremel (http://www.machinemart.co.uk/images/.../060810763.jpg)
and other one with high grid diamond coated conical tool(the last image on right)
with spindle rotates at 5-7K rpm
i hope they will solve my problem.

Thanks and Regards

[Mark Smith]

Student, we stock the engraving tools you seek >> http://www.nicolaidiamant.com/swf_ca...cnc/index.html Call me with any questions.

[stevespo]

I'm new to stone work, but experienced with wood, plastics, mother of pearl/abalone and non-ferrous metals.

I need to profile some small shapes out of a "sandwich", made up of a .060" layer of a dense acrylic, a .030" layer of granite, and a .030" layer of another dense acrylic.

The tool diameter would be something around .125" (or smaller) and I also need to drill some 1/16" holes.

I'm experimenting with some carbide tooling as well as diamond coated tooling, with very little success. I'd like to be able to do this dry, but could run coolant if necessary.

I've seen the videos of people engraving granite (dry) with specialized tooling (diamond?), but the details are very sketchy.

Any pointers to tooling, feeds/speeds, or other parameters would be greatly appreciated.

I should also mention that I have a small (but sturdy) benchtop wood router, with a 2.2kW high speed spindle. Aluminum frame, steel rails, BLDC servos motors. Perhaps an entirely different class of machine is necessary for this work?

I'm eager to get this project underway.

Steve