# Options For High Speed Milling



## TomS

Now that I have a few weeks of run time on my CNC conversion (PM-932) it's become apparent that the 1970 RPM top speed is limiting me on feed rate and not nearly fast enough for small end mills.  I've been looking around the internet to see what my options would be for a high speed spindle and have a short list of three ways to go.  Subject to change of course based on the feedback I'll get from the experts on this forum.

The three options I've come up with so far are:

1.  Replace the mill motor with a 2 - 3 HP three phase motor and wire in a VFD.

2.  Buy a high speed air cooled spindle (about 1.5 to 2.2 kw) and VFD.

3.  Buy a router motor and variable speed controller.

All three of these options have pro's and con's.  Option 1 is relatively inexpensive.  My guess is about $500 to $600 for the motor and VFD.  But I think the upper RPM limit is about 6000 RPM.  A little slow for 1/4" and smaller end mills in mild steel and aluminum, particularly if they are carbide.  Option 2 can either be inexpensive or the most expensive option depending on where I buy the spindle and VFD.  Ebay sells an Asian spindle and VFD for about $350.  Not sure of the quality I would be getting for this price but I'm not optimistic it's top quality equipment.  On the other hand one U.S. vendor has the 1.5 to 2.2 kw spindles listed at just shy of $900.  Add in a VFD and the package price is around $1,200.  Then there's option 3 which I'm not sure is viable but certainly is the least expensive.  I would think the bearings for a name brand router motor would be good quality but will they hold up to the rigors of machining metal?  What about motor torque at lower RPM's, e.g. 8,000 to 12,000?  I would think flood coolant is out of the question as well as mist and cutting oil.

I'm anxious to here everyone's comments and opinions on how best to approach this high speed milling question I have.  

Thanks in advance.

Tom S


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## REdington

#1  Fist question I would have before adding any speed to the original spindle is find out how much more rpm the bearings will handle.

#2 If I ever move up to a high speed spindle, this is the one I'm going to get. By most accounts I've seen, the guy that owns Light Object is real easy to get along with and goes out of his way to make most happy (some you cannot make happy no mater what).

http://www.lightobject.com/15KW-24000rpm-CNC-Spindle-220V-Germany-shaftball-bearing-P638.aspx

#3 I've seen some of the router guys use the Dewalt 611 trim router with success on aluminum. The variable speed is PWM so it shouldn't loose torque at lower rpm. BTW that is what I have on my CNC router that isn't finished yet.

Rodney


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## JimDawson

I just put a Porter-Cable 7518, 3 1/4 HP motor on my router.  About $300 from many sources, I bought mine from Grizzly.  Adjustable speed 10 to 22 K.  Speed control seems to work well, but a little slow ( a half second or so) to recover after a heavy momentary load.  In general it seemed to work fine.  I ran it for about 24 hours in two 12 hour runs at 13K, didn't even get warm.  I was cutting 1.25 thick UHMW in this case, but a lot of guys use them on aluminum from what I understand.   I would expect to get 400-500 hours out of it.  You can get collets for them from 1/8 to 1/2 inch, by 16ths.  I would not be afraid to use mist coolant with it, the fan in it blows down and is like a leaf blower, it must take about 1 hp just to run that.

For really high speed work in the mill, I use a Harbor Freight pencil, air die grinder (about $20) mounted in the spindle.  The specs say 50K, but I normally don't run it flat out.  Seems to be holding up well, and I have a lot of hours on it.  I have run endmills down to 0.020 with it.  I use an in-line oiler with it.


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## jumps4

Hi Tom
this is like what I have... (I got the 1.5 but with the er20 collet I wish I would have gotten the 2.2. It will take tools up to 1/2" )
coolant is not a problem because the air blows down towards the tool and it will not enter the motor.
Ebay item number 251263506939 $355 and free shipping
Steve


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## RJSakowski

Tormach has some solutions for high speed spindle requirements.  http://www.tormach.com/product_pcnc_acc_spindle.html

Possibly some ideas on how to solve your problem?

Bob


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## TomS

Thanks for your input.  I did some more searching and reading last night trying to determine which option will cover an RPM range from 7,000 to about 15,000.  If I use carbide end mills exclusively this would get me into the desired RPM range.  From what I learned router motors don't work well below 10,000 RPM.  How slow can you effectively run a high speed spindle without losing too much torque?  I'm mostly looking to machine aluminum and mild steel so I need something that has enough power in the lower end of the RPM range.  A 3/8" end mill would be the largest end mill I would use in such a set up.    

Tom S


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## TomS

jumps4 said:


> Hi Tom
> this is like what I have... (I got the 1.5 but with the er20 collet I wish I would have gotten the 2.2. It will take tools up to 1/2" )
> coolant is not a problem because the air blows down towards the tool and it will not enter the motor.
> Ebay item number 251263506939 $355 and free shipping
> Steve



Steve - I got the high speed spindle idea from your build thread.  Are you happy with the quality of the spindle and VFD?  

Tom S


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## TomS

RJSakowski said:


> Tormach has some solutions for high speed spindle requirements.  http://www.tormach.com/product_pcnc_acc_spindle.html
> 
> Possibly some ideas on how to solve your problem?
> 
> Bob



Thanks Bob.  I looked at the Tormach offerings and the Spindle Speeder is interesting but the price (~$1,400) is out of my price range.  The Companion Spindle is similar to a router motor and the price is attractive.  Looks like anything electric driven is limited on the lower end to 10,000 RPM.

Tom S


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## countryguy

I have the Dewalt 611 trim router and think it is grand!  I also have the same air powered pencil spindle noted above as Jim and the guys here helped me get my high speed engraving spindle basics nailed down.    The only item I have a comment on is related to Carbide small end mills on high speeds.  I tried that.  Broke most everyone of them (with CNC being used for engraving).   So brittle and delicate.   Of course, I am also very new and learning but did fare much better with HSS in those really small sizes. I now also love Cobalt.   I'm just curious what type of material you would use these Carbides and higher speeds upon?     When I used my setup for engraving on Brass- the carbide would just not last long when cnc driven.   I also ran them on Steel and Stainless.  In the end I needed a mount w/ a spring spindle and HSS.   Thought I would toss in my newb feedback on really really small carbide EMs


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## RJSakowski

Gunrunner you need to order a set of these for the Z axis hand crank. Bill did you just spit coffee on your monitor? :rofl:

View attachment 253356


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## TomS

countryguy said:


> I have the Dewalt 611 trim router and think it is grand!  I also have the same air powered pencil spindle noted above as Jim and the guys here helped me get my high speed engraving spindle basics nailed down.    The only item I have a comment on is related to Carbide small end mills on high speeds.  I tried that.  Broke most everyone of them (with CNC being used for engraving).   So brittle and delicate.   Of course, I am also very new and learning but did fare much better with HSS in those really small sizes. I now also love Cobalt.   I'm just curious what type of material you would use these Carbides and higher speeds upon?     When I used my setup for engraving on Brass- the carbide would just not last long when cnc driven.   I also ran them on Steel and Stainless.  In the end I needed a mount w/ a spring spindle and HSS.   Thought I would toss in my newb feedback on really really small carbide EMs



My choice of materials is aluminum and mild steel.  I'm considering carbide because the high speed spindles and router motors I've looked at are rated 10,000 RPM on the low end.  10,000 RPM is too fast for a 1/8" HSS end mill in mild steel.  My mill's top speed is 1,970 so I have a gap to fill between 2,000 and 10,000 RPM.

I've been in the machining industry my entire career (45+ years) so I understand feeds, speeds, chip load, chip evacuation, etc. but I don't have any experience running end mills smaller that 1/8" so I appreciate your feedback on using small diameter carbide end mills.   Always something new to learn. 

Tom S


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## TomS

Gunrunner you need to order a set of these for the Z axis hand crank. Bill did you just spit coffee on your monitor? :rofl:

View attachment 253356


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## RJSakowski

TomS said:


> My mill's top speed is 1,970 so I have a gap to fill between 2,000 and 10,000 RPM.



That is going to be your problem Tom. It doesn't appear to me that you will be able to cover your desired range with a single option.

I took a look at the PM932 brochure at it appears that this essentially the same as the Grizzly G0755 which I have some experience with.  If you are considering changing the motor, how well will your spindle bearings hold up running at six times the rated spindle speed and how well balanced is your spindle?  Tormach goes so far as to cut a second keyway on their R8 collet for the TTS system. Finally, how would the gear train hold up to the increased speed?  

For what it is worth, the Tormach 770 uses a 1 hp. (1.5 hp peak) 3 phase vfd controlled spindle motor coupled with a dual pulley system, low range 175 -3250 rpm, high range 525 - 10200 rpm.  The motor maxes out at just under 7,000 rpm.  It is fairly anemic at the low end of the speed range, however.  Based on your gear train, that still wouldn't get you to 10K.

Regarding the speed increaser approach, here is a link to a German company:  http://www.henningerkg.de/produkte/...lauf-frasspindeln-mit-ubersetzung-16/?lang=en.  I suspect that the price will make the Tormach solution look like a bargain though.  

Here is a wild idea.  Rather than using a gear train to achieve the speed increase, how about a hydraulic system.  A relatively high volume hydraulic pump driving a low volume turbine.  The advantage would be the mechanical isolation between the input and output.  With the right drive coupling, any spindle runout would not be of consequence..  The output drive would be a turbine on a shaft with high speed bearings and something like an ER20 collet chuck.    Hmmm......

Bob


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## JimDawson

Somewhere I saw a pretty cool setup on a mill, it may have been on HM but I don't remember.  It had a high speed spindle that was held in the mill spindle in a collet.  It was driven with a timing belt powered by a router motor mounted to the side.  This would allow a speed reduction from the router spindle.  A 2:1 reduction would put you in the speed range that you are looking for with a 2:1 increase in torque.


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## jumps4

Tom 
I am quite impressed with with the unit I purchased and how well it works, If I had it to do over though I would have purchased the 
2.2 to get the larger collet size. ( I can only use up to 7mm ) I have never wired my vfd to my controller I manually turn it on and off because I also use it on my Sherline mill for making really small parts and 4 axis engraving. 
One thing that I do notice and try to stay ahead of is the micro fine chips coming off of the cutter. I keep a guard as close as possible to the work and place a 
rag over the table drain to catch everything I can. They are so fine they will float on the coolant and get into everything including your fingers it is like your playing
with a cactus. When I use it I vacuum everything to keep it out of the ways. when doing steel placing a magnet by the drain may even be a good idea.
Steve


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## TomS

RJSakowski said:


> That is going to be your problem Tom. It doesn't appear to me that you will be able to cover your desired range with a single option.
> 
> I took a look at the PM932 brochure at it appears that this essentially the same as the Grizzly G0755 which I have some experience with.  If you are considering changing the motor, how well will your spindle bearings hold up running at six times the rated spindle speed and how well balanced is your spindle?  Tormach goes so far as to cut a second keyway on their R8 collet for the TTS system. Finally, how would the gear train hold up to the increased speed?
> 
> For what it is worth, the Tormach 770 uses a 1 hp. (1.5 hp peak) 3 phase vfd controlled spindle motor coupled with a dual pulley system, low range 175 -3250 rpm, high range 525 - 10200 rpm.  The motor maxes out at just under 7,000 rpm.  It is fairly anemic at the low end of the speed range, however.  Based on your gear train, that still wouldn't get you to 10K.
> 
> Regarding the speed increaser approach, here is a link to a German company:  http://www.henningerkg.de/produkte/...lauf-frasspindeln-mit-ubersetzung-16/?lang=en.  I suspect that the price will make the Tormach solution look like a bargain though.
> 
> Here is a wild idea.  Rather than using a gear train to achieve the speed increase, how about a hydraulic system.  A relatively high volume hydraulic pump driving a low volume turbine.  The advantage would be the mechanical isolation between the input and output.  With the right drive coupling, any spindle runout would not be of consequence..  The output drive would be a turbine on a shaft with high speed bearings and something like an ER20 collet chuck.    Hmmm......
> 
> Bob



Bob - I have to agree with you that the spindle bearings, even if I upgrade to high quality, probably max out at about 6,000 RPM.  The gear train less than that.  The three phase VFD conversions I've seen have a top speed around 6,000.  Speed increasers tend to be expensive but I'm still looking.

Tom S


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## TomS

jumps4 said:


> Tom
> I am quite impressed with with the unit I purchased and how well it works, If I had it to do over though I would have purchased the
> 2.2 to get the larger collet size. ( I can only use up to 7mm ) I have never wired my vfd to my controller I manually turn it on and off because I also use it on my Sherline mill for making really small parts and 4 axis engraving.
> One thing that I do notice and try to stay ahead of is the micro fine chips coming off of the cutter. I keep a guard as close as possible to the work and place a
> rag over the table drain to catch everything I can. They are so fine they will float on the coolant and get into everything including your fingers it is like your playing
> with a cactus. When I use it I vacuum everything to keep it out of the ways. when doing steel placing a magnet by the drain may even be a good idea.
> Steve



Steve - thanks for the info.  At this point I'm not sure which direction I'm going.  Still searching and looking at what's out there.

Tom S


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## TomS

JimDawson said:


> Somewhere I saw a pretty cool setup on a mill, it may have been on HM but I don't remember.  It had a high speed spindle that was held in the mill spindle in a collet.  It was driven with a timing belt powered by a router motor mounted to the side.  This would allow a speed reduction from the router spindle.  A 2:1 reduction would put you in the speed range that you are looking for with a 2:1 increase in torque.



Thanks for turning the light on.  I now remember an article in either HSM or MWS magazines a year or so ago.  I'll have to dig through me magazine stack and find it.

Tom S


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## jbolt

When I did the research on a spindle for the CNC router we built for the high school robotics team I spoke with many suppliers, manufactures and end users ranging from the hobby level to industrial. Our requirement was to cut aluminum from sheet to 1/2" with high precision. My conclusions were that the wood routers and low end Chinese spindles would not hold up based on our indented usage. The bearings are not up tot he task and they are not designed to plunge repeatedly (drilling). We settled on an industrial 3hp spindle made in Italy specifically configured for our application with the correct radial and axial bearings. The Spindle and Drive were $2800.

I think you can get away with a lot from low end spindles cutting just aluminum on a hobby level but steel is a whole other animal. 

Also consider the feed rate limitation of your mill. The faster you turn the cutter the faster feed rate you may need to maintain the recommended chip load. I am finding my little CNC router cannot move fast enough to properly use some cutters even at the min spindle rpm of 8K.


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## jbolt

In this build thread he did a belt drive/VFD conversion on a PM45 that ran at 8K with a good quality motor/VFD and I believe high end AC bearings on the spindle.

http://www.cnczone.com/forums/benchtop-machines/122462-cnc-cad.html


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## compsurge

jbolt said:


> In this build thread he did a belt drive/VFD conversion on a PM45 that ran at 8K with a good quality motor/VFD and I believe high end AC bearings on the spindle.
> 
> http://www.cnczone.com/forums/benchtop-machines/122462-cnc-cad.html



I was going to suggest this as option #4. A spindle bearing upgrade and a two range belt drive should work very well. The Chipmake 5000 build is a great thread.


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## countryguy

Gunrunner you need to order a set of these for the Z axis hand crank. Bill did you just spit coffee on your monitor? :rofl:

View attachment 253356


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## TomS

I think I have a workable plan.  I'm going to buy a 2 HP router motor that has a speed range of 8,000 to 23,000 RPM and a router speed controller.  The largest end mill I'll run with this setup is 3/16" and small DOC in aluminum so I don't think I'll have a problem with reduced torque with RPM's below 8,000.  Mostly I'm looking at end mills in the 1/64" to 1/8" size range cutting aluminum and some plastics.  For larger end mills (up to 1/2") I'll be able to run them at the speed appropriate for the material I'm cutting.  We'll see how this works out.

Thanks to all for your input.

Tom S


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## TomS

TomS said:


> I think I have a workable plan.  I'm going to buy a 2 HP router motor that has a speed range of 8,000 to 23,000 RPM and a router speed controller.  The largest end mill I'll run with this setup is 3/16" and small DOC in aluminum so I don't think I'll have a problem with reduced torque with RPM's below 8,000.  Mostly I'm looking at end mills in the 1/64" to 1/8" size range cutting aluminum and some plastics.  For larger end mills (up to 1/2") I'll be able to run them at the speed appropriate for the material I'm cutting.  We'll see how this works out.
> 
> Thanks to all for your input.
> 
> Tom S



Slight change in plans.  I bought the router as planned and currently working on the mount to adapt it to my mill.  Pictures to follow once the machining is done.  As some of you said the motor torque is significantly reduced at lower speeds.  I wasn't too worried about the reduced power as my plan is to run small end mills (1/64" - 3/16") most of the time.  But you never know.  Reading through some of the woodworker forums I ran across this website - http://www.vhipe.com/product-private/SuperPID-Home.htm.  The woodworkers rate it very high, RPM can be reduced and controlled to 5000, and it's compatible with Mach 3.  Price isn't too bad either.  Anyone have experience with this board?

Tom S


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## compsurge

That's what I'd get if I wanted a simple solution for router control. If I use an existing Porter Cable 3 HP router for a future CNC router table, I am going to get the SuperPID. I haven't had first-hand experience, but I would trust the satisfied users on the woodworking forums. At the cost after router motor and the SuperPID, you should compare one of the generic Chinese 2.2kW spindle motors from eBay with VFD.


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## TomS

compsurge said:


> That's what I'd get if I wanted a simple solution for router control. If I use an existing Porter Cable 3 HP router for a future CNC router table, I am going to get the SuperPID. I haven't had first-hand experience, but I would trust the satisfied users on the woodworking forums. At the cost after router motor and the SuperPID, you should compare one of the generic Chinese 2.2kW spindle motors from eBay with VFD.



The lowest cost I've found for a 2.2kw air cooled spindle and VFD is about $360 delivered.  Water cooled spindles are a bit more because they require a water pump.  My router cost $150 (Porter Cable 1-3/4 HP) and the Super PID is $155 plus shipping.  Adding in the miscellaneous hardware to make the Super PID run puts the price about the same as the Chinese air spindle setup.  I have Chinese motors and electronics on my mill and they work just fine so quality doesn't appear to be an issue.  I've already bought my router so the Super PID is the direction I'm headed.

Thanks for your input.

Tom S


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## chevydyl

I know you guys have this conversation going into motors and bearings but I would like to point out that High Speed Machining isnt exactly the spindle, Ive always understood it to be a tool path technique that removes the metal faster than standard tool paths. Advanced Pocket is a type of HSM. All that being said, I too would like to have some more speed out of my spindle, 4200rpm max right now, I do have a Mitsubishi VFD but ive read that its hard on the motor to run em up much more than the plate rating.... not sure if its really fact to a point or what but I don't really turn mine up that much, anyone can chime in on that.

edit: LOL I just reread your title, MILLING, key word eh. Dummy haha


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## TomS

chevydyl said:


> I know you guys have this conversation going into motors and bearings but I would like to point out that High Speed Machining isnt exactly the spindle, Ive always understood it to be a tool path technique that removes the metal faster than standard tool paths. Advanced Pocket is a type of HSM. All that being said, I too would like to have some more speed out of my spindle, 4200rpm max right now, I do have a Mitsubishi VFD but ive read that its hard on the motor to run em up much more than the plate rating.... not sure if its really fact to a point or what but I don't really turn mine up that much, anyone can chime in on that.
> 
> edit: LOL I just reread your title, MILLING, key word eh. Dummy haha



FWIW I asked Matt if running a 3450 RPM motor on my PM-932 would have a negative affect on the spindle bearings and headstock gears.  His advise was the higher speed would not be good for the gears and bearings.  So if you increase spindle speed the existing bearings may be a limiting factor.  Upgraded bearings would solve this problem, to a point, but then the gears become the limiting factor.  I guess that's why most gear head VFD conversions are belt drive.  As I remember your mill is variable speed so gears may not be part of your equation but bearings may be depending on how fast you want to go.

Tom S


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## chevydyl

I agree on the bearings, and yes Im vari-speed, Bridgeport clone. I would be especially hesitant of the bearings because of the cost of the machine, everything is purpose built, and not much room for more out of it. The max freq I run is around/under 75, 5200 rpm max, and not for very long durations.


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## TomS

chevydyl said:


> I agree on the bearings, and yes Im vari-speed, Bridgeport clone. I would be especially hesitant of the bearings because of the cost of the machine, everything is purpose built, and not much room for more out of it. The max freq I run is around/under 75, 5200 rpm max, and not for very long durations.



I'm limited to 1970 RPM so running an end mill smaller than 1/8" is virtually out of the question unless I crank the IPM way down and wait hours for the program to run.  I want to do engraving.  That's what's driving me to an auxiliary spindle.

Tom S


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## chevydyl

fwiw ive had success engraving alum with my 4200 rpm, running about 5-6ipm, WD40,  I use a Micro 100 60* split point 1/8th shank, and .062 2fl ball from Harvey Tools


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## TomS

chevydyl said:


> fwiw ive had success engraving alum with my 4200 rpm, running about 5-6ipm, WD40,  I use a Micro 100 60* split point 1/8th shank, and .062 2fl ball from Harvey Tools



Once I get my auxiliary spindle up and running I'll give those cutters a try.  With a spindle speed of 1970 I'd have to be at 2 IPM +/- to get the chip load where it needs to be.  At that feed rate I'd have to shave twice before the program is done.  LOL.  The new spindle will go as low as 5000 rpm and as high as 30000 which gives me more options.

Tom S


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## TomS

Today I finished up the router bracket and mounted the router on the mill.  The bracket started out as a piece of 1-1/2" x 5" x 13" aluminum.  I wittled it down to what you see in the pictures.  

I ordered the Super-PID speed controller about a week ago.  Hoping it gets here before Thanksgiving so I can wire up the electronics and start engraving.  Here's a few pictures of the bracket and router on the mill.

Tom S


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## JimDawson

Nice job!  Looks like it will work well.  Sure is fun to make piles of aluminum chips with a CNC!


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## chevydyl

nice job man


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## TomS

Thanks guys.  I appreciate the your comments.

Tom S


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## TomS

In between home projects and some traveling I finally got my high speed spindle up and running.  I mounted a Porter Cable 1-3/4 HP router on a bracket that clamps to the quill.  Spindle speed is controlled by a SuperPID speed controller.  The SuperPID controls spindle RPM from 5000 to router max speed of 27500.  It does everything as advertised.  The only downside is their communication was not good.

Here's a shot of a 1/2" 2 flute carbide end mill taking a .050" wide x .050" deep cut in aluminum at 6135 RPM feeding at 30 IPM.  It cut smooth as silk and this was reflected in the finish.    


And a picture of the control panel.  Pretty simple.  I used a 8" x 8" x 4" plastic enclosure box.  It houses the SuperPID circuit board, a 3" fan and a 5vdc and 12 vdc wall wart.  I mounted an on/off switch so I don't have to reach into the mill enclosure to turn off the router.  The router rpm didn't vary more than +/- 20 rpm while cutting.  It's also got a heat sensor.  It reads 8 deg C.  A little cold in my shop today.


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## chevydyl

Nice job, I'm jealous, I actually got my router sitting out so I can make a mount. I have a Bosch colt, but you can only get 1/4" collets for it so whatever


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## chevydyl

So I'm curious how square it is, do you have to tram when you install it?


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## TomS

chevydyl said:


> Nice job, I'm jealous, I actually got my router sitting out so I can make a mount. I have a Bosch colt, but you can only get 1/4" collets for it so whatever



Thanks.  Have you tried PreciseBits.com for collets?

Tom S


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## TomS

chevydyl said:


> So I'm curious how square it is, do you have to tram when you install it?



I haven't checked tram yet.  Before I finish bored the mounting bracket bores I checked tram on my manual mill drill and bored both holes in one setup.  It should be close but I will check it.

Tom S.


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## JimDawson

chevydyl said:


> Nice job, I'm jealous, I actually got my router sitting out so I can make a mount. I have a Bosch colt, but you can only get 1/4" collets for it so whatever



These guys also, I bought a full set for my PC.  http://elairecorp.com/routercollets.html

It looks like the Bosch Colt will only take a maximum of 8mm, you may have to get a bigger router if you want to go to 1/2 inch


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## chevydyl

Thanks for the tips, yeah I may want to go to half inch, I'm really loving my CGS Ferocious end mills and a 1/2 inch wants about 8-10k rpm for starts


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## TomS

chevydyl said:


> So I'm curious how square it is, do you have to tram when you install it?



Today I checked the mill spindle to table and I'm within .0005" in X and Y.  No complaints there.  Put the indicator in the router and tram is out .0085" in X and .0105" in Y.  I was expecting it to be within a couple thou of the mill spindle so I'm not a happy camper at the moment.  

I have to do some checking but my guess is the OD of the router housing is not in line with the spindle.  It's a stack up assembly with the bearings in housings that mount on each end of the stator so there may be an accumulation of manufacturing tolerance.  Whatever the cause I need to correct it.  My plan is to remove the bolt on collar and overbore the router end of the mounting bracket about .030" for clearance.  Then I can drill and tap the bolt on collar for set/jack screws adjacent to each of the four bolts and use those to tram the router.

Tom S


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## chevydyl

Bummer, hope the solution works out for you.


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## TomS

chevydyl said:


> Bummer, hope the solution works out for you.



It'll work out.  I built this without any adjustment features with the thought that everything was square and true.  The plan is to build in adjustability.  I have a preliminary plan but need to think it through before I start modifying anything.

Tom S


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## chevydyl

It for sure has me rethinking my plans for mounting up my Colt, I'd rather not have to tram my head just to use it


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## TomS

chevydyl said:


> It for sure has me rethinking my plans for mounting up my Colt, I'd rather not have to tram my head just to use it



I agree with you.  I don't want to tram in the router every time I use it either.  So I'm going to overbore the mounting bracket on the router end.  Then I can shim the bolt on collar to get the tram where I want it.  No different than tramming the main column which we all do from time to time.

Tom S.


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## chevydyl

I was thinking I would just tram the head in both planes,(bridgy clone) but.... that's a lot of time with the tenth indicator, plus the offset of the router would be a pita to deal with tramming


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## TomS

chevydyl said:


> I was thinking I would just tram the head in both planes,(bridgy clone) but.... that's a lot of time with the tenth indicator, plus the offset of the router would be a pita to deal with tramming



Tramming the router is a one time task, unless I crash it.  I'm willing to spend the time now and get it out of the way so when I need to do precise work I'm ready to go.  It's just the nature of the beast so to speak.

Tom S.


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## chevydyl

so youll be leaving the router and bracket attached at all times? or your thinking that attaching the bracket to the quill will keep tram after removal and installation.


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## TomS

chevydyl said:


> so youll be leaving the router and bracket attached at all times? or your thinking that attaching the bracket to the quill will keep tram after removal and installation.



I'll remove the router from the bracket when using the main spindle.  When using the router I cut down the flow of coolant to a trickle but when using the main spindle it's wide open.  I wouldn't want coolant getting into the router motor.  My Z axis DRO is attached to the bracket so the bracket will will stay unless it gets in the way of my set up/fixturing.  This is my intent but we'll see how it goes and adjust from there.  

I loosened the bracket and moved it vertically then retightened the clamp bolts.  Checked the tram and it was the same.  I'll do a more thorough check later but my initial check indicates tram should be repeatable.  

Tom S.


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## TomS

I originally checked the router tram using 123 blocks.  Rechecking the tram with the indicator sweeping the table tram was out .005" in X and Y.  Evidently I had some debri under the 123 blocks and got erroneously high readings.  Ended up with a .003" "U" shaped shim under one of the collar bolts.  Tram is now within .0005" in X and Y. 

Haven't checked repeatability yet but will see how it works out the first time I remove the router and bracket.

Tom S.


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