[SSN Vet]

I want a high speed milling option for my CNC X3 (but the question is generic to any CNC mill).

The intended purpose is for cutting wood on the mill, as well as using small cutters on Aluminum.

Here's a pic I pulled off of Bob Warfield's site that shows what I have in mind.

Attachment 234394

I'm stuck deciding for either the Bosch Colt PR20EVSK or the Makita RT0701C, both of which get great reviews on the wood working boards.

Makita
1.25 HP
10,000 - 30,000 rpm
1/4" & 3/8" OEM collets available
no after market support (would have to use a collet reducer to run small cutters)

Bosch
1.0 HP
16,000 - 35,000 rpm
1/4" max size collet (which I think is adequate)
1/8" after market collets and high precision after market collets available.

So my questions are....

Would I be better with the extra rpm at the low end or the high end?

Would using a collet reducer on the Makita give me too much run out?

I've inspected both and they are each really nice units and the price is the same. Both have soft start and speed control to put more amps to motor under load.

[hoss2006]

.

[Hypnotoad]

I've got the Bosch. From my woodworking experience the extremes of the RPM range aren't used much in practice. The 1/4" shank has been a limitation at times -- far more interesting 3/8" bits out there -- but in a CNC context that's irrelevant I guess.

I've put a fair amount of miles on my router. I don't have a full size router so it gets used for things it's not really up for. Over the years I've broken a collet and had to do some maintenance on the brushes. Not bad considering the abuse.

What's the advantage of a router when going at wood? The higher RPM let's you move faster thru the material? My G0704 is on the way and I sort of just assumed I could work hardwood with it.

[SSN Vet]

Well, I went back to the BORG and inspected both more closely, after reading some negative reviews about the Bosch having a problem of the body slipping in the base.

Yup... the reviews were spot on, and I could easily rotate the body and disengage the depth setting threads and move it up and down. This wouldn't be a big deal for use on a CNC, as the base get's removed. But the Bosch has a plastic body with three metal bearing pads spaced evenly about the circumference. So when the base clamps to the body, the plastic flexes slightly, preventing a good firm metal to metal lock up. THIS IS AN ISSUE FOR CNC USE.... as the typical mounting bracket is a circumference clamp.

The Makita has an all metal body, and though the depth adjustment in the base is course, that is also N/A for CNC use, as the base is removed.

Both have spindle locks for single wrench tool changes. And while the lock on the Bosch is tucked in nicely into the body, it will require add'l machining in the mounting to provide clearance. The lock on the Makita is under the body.... so it's not as easy to access, but it is more out of the way and will not require a clearance cut.

Leaning towards the Makita, but would love to hear feed back on collet adaptor run out, and speed range.

Hypnotoad.... we use more 3/8" tooling than anything else on our CNC gantry router at work. So your point is valid.

But then again, I'm hoping to run 1/16" end mills, for some smaller scale and intricately detailed relief work.

We run almost everything at 18,000 rpm on the CNC at work (accept for the occasional large cutter), but that's because it is the spindles max speed. We make our adjustments with feed speed and depth of cut, concentrating on clean cut and no burning. We adjust the feed speed to get hot chips, which means the heat is going out of the cutter and into the waste.

[Connor]

The Bosh Colt is a VERY good router for CNC. You may want to check the wood router forum on the topic. I have one and have had no issues. I use Collets from Precision solid carbide tools for woodworking and metal forming.
Not sure what your talking about with regards to the plastic. As far as machining out extra access for the spindle lock, that's not a big deal.

Thanks, Billy

[wizard]

I'm not a big fan or Bosch.

For ease of installation make sure the selected router has a round body that is easy to mount and adjust if needed. There are a few trim routers out there where the body followed the design of larger routers with the base that slips on the tubular motor housing. This appears to be a new example: Porter-Cable. I can't saY if it is any good as I've never used one.

[SSN Vet]

Following up, I purchased the Makita...

I think I have the collet challenge solved as I read on another forum where a guy modified a universal die grinder collet buy turning it down ~5 thou at the base. I measured my 1/4" die grinder collet an it's very close. So I ordered a 1/8" collet off eBay for $4 and was pleasantly surprised at the quality of the part.

At 10k rpm, you can barely hear the Makita.

[NSchlee]

I use the Makita, very little run out, metal body and the body is 65MM so it will fit the imported tables with a 65mm spindle clamp.
The only drawback when using with Chinese tables is, the router will not drop down low enuf in the mount, you'll need to add spacers on the table to use.

Neal