Need help building a cnc-cutter

[Blackrat]

There is a machine on cnczone that does exactly this... I'll find the link

[Boyan Silyavski]

You can laser cut it too, though you need some additional things to consider like good ventilation, what power you need and so. Seems 50-60w will cut 1mm without problems. the best would be to find somebody to do it first for you so you know firsthand the eventual problems and know what power you need for the material.. But the benefits are quite great, starting from detailed perfect finish/if you manage it/ and practically no consumatives apart from the life of the tube. Plus Chinese machines are quite cheap.

On the other hand you will need vacuum holder, high quality carbide bits. But the good part is that you will be able to shape yourself the molds from different materials.

At the end its up to what is your exact need.

[Blackrat]

he means raw carbon .... before its had epoxy applied to it

http://www.cnczone.com/forums/diy-cn...8-cnc-cad.html

for me the hardest part is understanding the post processor for g-code to turn the head to follow the line its cutting

[Boyan Silyavski]

Then you need something similar to drag knife, rotating blade as you say. It must be offset from the shank . Aspire 4 is the answer. It can generate drag knife tool paths .
This is done without motorized knife. its very easy to modify the tool path in any program, once you get the grasp of it.

http://forum.vectric.com/viewtopic.php?f=27&t=19617

By the way i am exactly now developing a drag knife, which is cheaper and i would say better, meaning more functional than the original one. It seems i have to think also of rotary attachment. Just tomorrow would be going to friends house to do some tests. The normal drag knife with utility blade will cut it, though holding down the material will be a problem. But not necessaryly, cause this will be much cheaper than round blades, if managed to achieve. Will report my findings, though glass fiber cloth, i dont have carbon fibre cloth.n

[Blackrat]

why must it be offset from the shank ?

[Boyan Silyavski]

why must it be offset from the shank ?

cause it rotates over the offset point, meanwhile the z is making the corner

[Blackrat]

i understand having it offset from the center point for a drag knife as this acts the same as a castor wheel on a trolley for example

but for a pizza cutter ?