I'm building a 5x10 foot CNC router for cutting 1" plywood, and is trying to figure out what spindle motor I need to put on it, and I'm at my wits end.

I'm ping-poinging between thinking that I need a 1/2 Hp motor at 30.000 RPM or maybe a 12Hp motor at 18.000 RPM. I have no idea.

I have cut some 1/2 inch MDF with a $30 1000w router, and that went resonably well, but I guess I'll be needing at least twize that to cut 1" plywood?

1000w is just about 1.2Hp, right?

What brands should I look at? - I'm hoping to get something for under $1200.-

So - what is your experience? How large should the motor be, and what brand should I go for?

Regards,

Michael, Denmark

It depends on how fast you want to go. The SMALLEST motor I would use is a Porter Cable 7518. http://www.porter-cable.com/index.asp?e=547&p=2819

At a certain speed, though, even this will not have enough power. Unfortunately, for the next step up, the price goes up at least 10x.
Look here: http://www.ekstromcarlson.com/router_packages.htm
http://www.shopbottools.com/routers.htm

Our 12HP router at work can cut 3/4" plywood at 10m per minute at 14,000 rpm, if that helps you at all. Tooling plays a big part.

I use a cheap chinese hand held router, that is attached to the cnc machine.
It is rated at 2400w and has variable speed control between 18000rpm and 28000rpm.

My router has had a tough life cutting a venere of 10mm MDF and 2 x 1mm aluminium sheet on both sides. I have gone through 2 of them in a year. The bearing is the weakest link. But I dont mind since the routers only cost $200 to replace. I treat them as a consumable item at that price, and the certainly pay for them selves 100 times over in terms of what they cut.

Possibly try one of these first, until you have earnt enough bucks to buy an industrial one.

The other consideration is cutting your material in two passes. The first pass at 1/2 inch and the second pass the full depth. This can help by not bogging down the router.

I want to go 300 inch/min or less.

//Michael