I'm wondering if anyone has tried using an X2 spindle housing casting and boring it out to hold a variable speed router motor. Most of the router motors have cylindrical bodies that would probably fit without too much problem in an enlarged cavity where the spindle goes. This could yield a 3.5 hp spindle with variable 8,000 -24,000 speeds. Someone on this forum must have tried this. Anyone?

Bill

It could be done as well as treadmill motors or a 3 phase with a VFD. Build a belt drive to get rid of the troublesome gears, upgrade the bearings and it should take lots more HP. With that said you have to think if the rigidity is there to push alot harder and deeper cuts. You have to watch the HP ratings on motors like that also you can find 10 different units that run the same rpm range and vary from 1-4 hp but draw exactly the same amps on the motor plate. An excellent example of this is I have a large cabinet table saw that is belt drive with a 4 hp motor plate says 15 amps. My aunt gave me a cheap small tablesaw that claims 4.5 hp and 15 amps also it is belt drive with a belt drive that utilizes the same pulley sizes. The motor on the cheap saw is about a 1/3rd the size and will easily choke out making lesser cuts on softer woods. Moral is there is no standardized power rating for these power tool motors so you dont ever know if its correct or inflated.

Good point, amps are probably the best indicator of motor power, not HP ratings. Router motors do seem to pack a lot of power into a small unit. Some are 15 amps.

Even the amp ratings cant be trusted. Motors wont usually draw the amps they say on the spec tag, the rating is the max amps it should draw while running. A 15a motor will usually run about 12-13 amps until it is a few years old then as things are wearing out it can go up. The table saw example is a good show of this. Putting a amp clamp on the power wire going into the unit would be the only way to figure out how strong it is. You cant access it on the stock cord so you would have to make a receptical box with the hot wire exposed so you could put the meter around it. Then multiply imput voltage by amps and you have the wattage of the motor.

Motors will also draw more power under a heavy load, than when spinning freely. The power (watts) required to spin the armateur are not the same as required to cut.
Its more like a car, you need a dynomometer to measure max power.

While the router motor is definately a viable idea and could work mechanically, an 8000+ rpm spindle speed would be utterly useless for any type of metal machining. If you had your mill dedicated to cutting wood only, it would be a great idea.

While the router motor is definately a viable idea and could work mechanically, an 8000+ rpm spindle speed would be utterly useless for any type of metal machining. If you had your mill dedicated to cutting wood only, it would be a great idea.

Where did you get that idea from? Small cutters need high rpms - especially in aluminium, 10-12k rpm is quite common on modern VMC's and Daytron make some amazing alloy-cutters that run at 60k rpm: http://www.datrondynamics.com/velociraptor.htm

YouTube - DATRON Hochgeschwindigkeitsbearbeitung von Aluminium

I don't understand though why it wouldn't be easier to just bolt a router to the side of an X2 head if needs be, or to use an easier to clamp router such as a Kress 1050FME.

Where did you get that idea from? Small cutters need high rpms - especially in aluminium, 10-12k rpm is quite common on modern VMC's and Daytron make some amazing alloy-cutters that run at 60k rpm: http://www.datrondynamics.com/velociraptor.htm

LOL! I guess I'm too old-school. The YouTube link was dead, but I did look at the other link.... WOW!, 60k RPM! I wonder what type of end mills they utilize in this range? I do realize that small end mills in aluminum need high RPM, but my experience in this relates to 1/8" dia. end mills in a Bridgeport, where the upper RPM range is more like 2200. I always thought that 60k rpm was the reserved province of Jig Grinders. Thanks for bringing me "up to speed". :)

Hi blades - I hope you don't think I'm rubbing it in - but you really do need to watch that video - with the sound down low unless you want bleeding ears! Talk about the preverbial hot knife through butter!

Just have a quick search for DATRON von Aluminium on youtube - I can't post the link without the forum software doing magic on it :(

Just because a Bridgeport can only manage 2200 rpm, that doesn't mean it's the ideal speed for aluminim - according to the excellent ME Consultant pro, the ideal rpm for a 1/8 endmill in aluminium is about 9400 - I don't have a copy of Machinery's handbook handy to confirm that the old fashioned way - yet!

When I last looked though, only the tiny desktop mills like the Taig and Sherline and the very nice but expensive Wabeco H(igh)F(req) mills offered spindle speeds above about 3k. I guess it's a cost cutting thing though...

Cheers.

This is not correct. 10,000 + rpm is great for aluminium.

As I understand it the two main problems with the use of routers are:

1) The stiffness of the bearing set-up is often not upto machine tool standard.

2) Many routers do not like continuous running for long periods.

The are right and wrong routers to use. I can’t tell you which is which so you will need to read around.

Phil

While the router motor is definately a viable idea and could work mechanically, an 8000+ rpm spindle speed would be utterly useless for any type of metal machining. If you had your mill dedicated to cutting wood only, it would be a great idea.

Are we talking about standard high-speed steel end mills at that type of RPM?

edit: I just watched that video! WOW!!!! I'm truly impressed!!

I have run my Milwaukee 5625 for over 6 hours for 1 job. At the end of the 6 hours, there was no perceptable heat in the motor.
The bearings in the Milwaukee are as good as any router I have tried.

The starting point for a 1/8" HSS endmill in aluminium is up around 10,000 to 15,000 rpm., depending on DOC etc, etc. Carbide endmills are double that.

Phil

Are we talking about standard high-speed steel end mills at that type of RPM?

edit: I just watched that video! WOW!!!! I'm truly impressed!!

The starting point for a 1/8" HSS endmill in aluminium is up around 10,000 to 15,000 rpm., depending on DOC etc, etc. Carbide endmills are double that.

Phil

Not quite.
A .125 HSS endmill at 200 SFM = 6112 RPM.
This is probably about the minimum you would want to run at.
Here's some nice calculators (http://www.americanmachinist.com/Calculators/SpeedsFeeds.aspx) and PDF charts (http://www.endmill.com/pages/training/spdfeed.html)for figuring speeds and feeds.
Very helpful.
Hoss

Thanks Hoss, The speed-feed charts are great. Bill