CNC Tool Advice

[oldtbone55]

Hi There, Would anyone have some advice on the proper type of end mill to use on pine that is not clear and has knots in it? I want to use some inexpensive pine as a test bed for making a guitar body on a CNC mill and was wondering if there are issues regarding the knots. I can get three kinds of pine, one with large knots, one with small knots, and clear pine. Clear pine is 3 times the cost of the knotty stuff (not the naughty stuff). I have a carbide bit that I would want to use but if there's a better option please let me know.

Thanks.

[LibertyMachine]

You'll be fine with whatever bit you have, honestly. Pine is so soft, you could almost run a tool in reverse and still make some headway.

Couple of concerns though:

Knots. You cut through them, they might very well come loose and shatter your tool. Try to plan your toolpath accordingly.

Speeds. What is your machine and it's specs? How fast can it go, what size is spindle? When CNC routing softer woods you want to move as fast as the machine is comfortable moving. The slower you go, the more the sawdust is going to pack in and create heat, and lots of it.

Of course, if it's a small X-Carve, there is only so much you can do...

Another option is MDF. It's relatively cheap, but does make a lot of fine dust. Not sure what thicknesses you are looking at, just a suggestion

[daniel_lyall]

you can use router bits on cnc routers, the cheap one's are good for ruff material and knots depending on the age of the timber can be very hard, and can pop out and break ya bits or get you, they hurt a lot.

With the cheap ones it only cost you a few dollars for a mistake, keep the good one's for good stuff cheap for cheap.

And MDF eats bits use the cheap one with that to.

A good places to get good cutters from is toolstoday

[oldtbone55]

Hey Seth, thanks kindly for your reply. I wanted to stay away from MDF
because of the fine dust but I may wind up using it because of the cost. I
wish I could answer your questions about the machine I'm going to use but
unfortunately I don't have that information. I may opt for the clear pine
as I can get a few bodies out of a 2*" *x 8" x 8' piece as well as some
pieces to practice making the fingerboard and neck and it'll cost me around
$50.. I'll get back to you with the machine information when I can get to
the shop, most likely later tomorrow.

As always, thanks for your help.

[oldtbone55]

Thanks kindly for the help. I hate using MDF because of the fine dust. No
wonder everyone tells me to buy carbide bits. The don't seem to last very
long with MDF. I only have carbide bits but I may take your advice and buy
some cheaper HSS ones. I may opt for the clear pine as it has no knots and
I can get a few bodies and fretboards from a piece that's 2"x8"x8' and
it'll be kinder than MDF.

Regards.

[daniel_lyall]

We get 10 1/4 and 1/2 carbide router bits at a time for $40 including shipping they last about 6 months in mdf, It's a waste to use $100 cutters in mdf.

pine with no knots is like butter.

When you start doing non play items just rember to slow down a bit if your useing fancy woods.

[oldtbone55]

Thanks very much Daniel. I guess I'll use the bits I have as I don't do CNC work everyday (I'm a hobbyist) and I'd rather use the pine as it is very soft and I really don't like the MDF dust even though I have a filtration mask. Besides, this way I can get that pine tree fresh scent in the shop without buying air freshners. By the way, the price you quoted for those bits is great. 

Cheers!

[daniel_lyall]

I meant $40 each lot of 10, $4 each is good for cheap cutters.

you can get them cheaper over your way these are the 1/4

http://www.ebay.com/itm/1-4-Shank-1-4-Blade-Woodworking-Double-Flutes-Straight-Router-Bit-Cutter-/33...

the 1/2 are Red same shape they are everywhere on flea bay.