[CanSir]

It seems like everyone recommends a variable speed router for CNC. Why is that? With CNC we have pretty good control over feed rates so wouldn't we just leave the router on it's fastest setting anyway?

Cheers!

[ger21]

Because most likely, the cnc router you build won't move fast enough to make up for the high spindle speed. When the spindle speed is too fast, it causes excess heat, which dulls your bits faster, which leads to more heat, and burnt wood before you know it.

Also, different tyoes of router bits, and different materials may require different feed speeds. The variable speed gives you a lot more options.

[Rodm1954]

It gives you more options and a quick way of adjusting speed if it isn't cutting as good as you would like it. Given that you are likely to be cutting plastics, aluminum and wood and using different size bits then being able to tweak the router speed on the run is an advantage.
I find aluminum and plastic the worst as they tend to melt and weld back to the job if you don't get the speed right.

Gerry beat me to it - I have to learn to type faster

[CNCRob]

When I first got into CNC'ing I couldn't figure out why it was bad to have too many rpm's. I thought it was better to make sure you were cutting the materal rather then take the chance of slowing it down. Then I started to understand it all. Now the way I look at it; it is kinda like having a car spin its tires at 50mph. It doesn't mean the car is going 50mph it just means the car is setting there or bearly moving wearing out its tires, and other componites. The same holds true for routers, when you are turning too many rpm's it doesn't always mean it is cutting any better, many times it just means excess wear and tear on the router and bits.

[CanSir]

Thanks guys. I'll keep looking for a variable speed router then!

Does anybody know where in Canada to get the best price on a Hitachi M12VC? $269 at the House of Tools seems really high compared to the $148 the U.S. guys are paying at Lowes. Trying to get something fixed under warranty might be a hassle if I cross border shop though...

[spalm]

http://www.amazon.com/gp/product/B00...lance&n=228013
M12VC $139

Steve

[Madclicker]

Thanks guys. I'll keep looking for a variable speed router then!

Does anybody know where in Canada to get the best price on a Hitachi M12VC? $269 at the House of Tools seems really high compared to the $148 the U.S. guys are paying at Lowes. Trying to get something fixed under warranty might be a hassle if I cross border shop though...

$148? I got mine for $114 at Lowes. Cheapest I could find anywhere...on or off the net.

[sdantonio]

if your not put off by refurbed stuff check out these guys

http://bosch.cpotools.com/routers/fi...617evs-46.html

also read the attachment

Steven

[spalm]

Too many guys named Steve.

Clicker, he is in Canada.

I have that Bosch, bought it as a refurb. I love it.

Steve

[sploo]

...also read the attachment

Steven,

The mill speed doc is very useful, thanks.

What sort of sfpm would you recommend for wood, or rather, MDF and plywood?

[Madclicker]

Too many guys named Steve.

Clicker, he is in Canada.

I have that Bosch, bought it as a refurb. I love it.

Steve

He may be in Canada, but here is what he said:

"seems really high compared to the $148 the U.S. guys are paying at Lowes."

[Semisentient]

Check out Boss Tools. They are a Canadian online tool supplier. $195 with free shipping.

http://www.bosstoolsupply.com/index....OD&ProdID=7097

[Semisentient]

This brings up a question though - Why not use an external speed controller? Seems like they can be had for prices starting around $20. This would allow speed to be adjusted on the fly... Plus I was just given a router that will work great for the CNC I am building, but it doesn't have speed control, so I have a vested interest.

[sdantonio]

This brings up a question though - Why not use an external speed controller? Seems like they can be had for prices starting around $20. This would allow speed to be adjusted on the fly... Plus I was just given a router that will work great for the CNC I am building, but it doesn't have speed control, so I have a vested interest.

I've wondered about that myself. The only thing I can think of is; would the air impeller that cools the router have a different pitch or configuration in the variable speed units to insure the same cooling at lower speeds. Also with a variac external controller you may be tempted to bring the router down to speeds where there is definitely not anough air passing through.

For example, if you were cutting mild steel with a .25in bit, your optimum spindle speed would be about 1000-1600rpm (for aluminum it would be about 3000rpm). I have not seen a variable router than goes much below 8000rpm.

Steven

[sdantonio]

Check out Boss Tools. They are a Canadian online tool supplier. $195 with free shipping.

http://www.bosstoolsupply.com/index....OD&ProdID=7097

I assume that is in Canadian dollars. Last time I visited there the exchange rate was about 30% which would just about account for the difference between the Lowes (US) price and tha Canandian price.

[Semisentient]

I assume that is in Canadian dollars. Last time I visited there the exchange rate was about 30% which would just about account for the difference between the Lowes (US) price and tha Canandian price.

Thing is, the exchange rate is now about 10%, but the price difference will still be there. I guess that's just the cost of being Canadian!

[sdantonio]

Gotta pay for that universal health care somehow

Lowes is a volume seller too. I'm sure that if you check some of the smaller woodworking specialty places like woodcraft supply their prices are higher (bad choice, just checked, they don't carry the hitachi, but you know what I mean).

[CanSir]

Well, Lowes website says that they are expanding into Canada in 2007. Hopefully I will be finished my first CNC router by then though! Thanks for the link to Boss Tool Supply semisentient - I'd never heard of them before and $200 including shipping is the cheapest Canadian source so far!

[Fifty_ohm]

The one thing I've noticed with the external variable speed controls is that when the bit loads up the revs drop on the router until I manually speed it up. With those variable speed routers (at least most that I've looked at) they maintain the speed when the load changes. I'll be upgrading at some point soon.

[yukonho]

No router in the world has enough torque to cut even butter at 1000-1600 RPM. Even 3000 RPM is too low, if you want to cut steel and aluminum, you need a mill. Mills are designed for high torque at low RPM's, routers are designed for high RPM and low torque. It is like trying to drag race a tractor trailer, or, conversely, pull a motor home with a crotch rocket, simply doesn't work either way.

Colin