Burned out on runout

[don62]

how does one solve the runout problem?
ran a pc for years, rebuilt bearings several times. seemed everytime i needed a joint to fit together (think puzzle pieces) there was slop in the joint - i assumed it was either a software problem or a function of the prt96. then late summer i got a milwaukee 5625 and did a few joints and they were outstanding - almost no runout. but soon the milwaukwee lost its trueness - first sign was a change in the sound of the router and now i needed to do a puzzle joint and the slop was awful. i run mainly solid surface - both cutting with a .25 onsrud spiral at 1.0 to 1.7 and engraving (usually 45 v). i understand a bearing change in a milwaukee is easier than a bearing change in a pc, but i sure do not want to do this every time i need a tight joint. what is the solution? slow down the cut speed? if i go to a spindle how long will that last before it needs bearings and how complicated/expensive is that. i am running a prt96 and always assumed it was the limiter on accuracy of cuts, but i am now convinced the router is the main culprit. need adult guidance pls!

[beacon14]

The spindle is the ultimate solution. I was changing bearings every 6-8 weeks on the PC, went well over a year on the 2.2HP spindle, then had them changed because I figured it must be time.

[navigator7]

Two Porter Cable routers?

[coolhammerman]

Don:
Have you upgraded to the G4 Gecko drives? When I did the accuracy was incredible and the speed more than doubled.

I do some micro cuts which have to be extremely accurate. See the attached photos. I normally use cutters smaller than 0.050 for these cuts.

I have a PRT 4896 PC 3-1/4 G4 upgrade. I also purchased a precision collet from PreciceBits.com for 1/4" and 1/8" shank bits. That combination seems to do the trick.

Ronco
7223
7224
7225

[don62]

Ron,
beautiful work! i thought my problem was the prt; however, when i installed the new milwaukee and did a puzzle joint the intersection of the two pieces was dead on - beautiful. after a few months use the milwaukee has a sound that says something is wrong (only makes the sound when it is cutting) and the intersection of two joints is horrible - i am convinced that the problem is the router, so before i consider upgrading the prt i need to solve this problem. what are you using - router or spindle? which way would you go for a small shop - two milwaukees that you keep replacing the bearings (<$1k) or a spindle ($2.5K)? thanks, don

[garyb]

water cooled spindle and VFD $400 -$650 for the budget minded
http://cgi.ebay.com/WATER-COOLE-MOTOR-SPINDLE-1-5KW-AND-MATCHING-INVERTER_W0QQitemZ230400340462QQcmdZViewItemQQptZL H_DefaultDomain_0?hash=item35a4ee31ee

[waynelocke]

Has anyone used one of these?

[garyb]

Only on a machine I went to work on for a customer, it was a 3hp water cooled, worked well while I was there.

[coolhammerman]

Don:
That's like asking me if I want a jointer or a planer because you need both of them. The real question is which one do I get first.

Fact: Spindles are better than routers.

Fact: Gecko Upgrade improves resolution by 2.5 times, therefore accuracy and speed. Imagine if you could only set points the the nearest 1/8" of an inch then someone showed you how to set points to the nearest 1/64"th. How much better would things fit with the better resolution?

Given that I'm an original cheapskate, I would (did) go for the G4 upgrade first. When I did it it was $1,250. I still use a PC router with upgraded collet, but I know a spindle is better. Can't afford it yet and the router is working great for now. When I get rich and famous I will then buy a 2.2hp spindle.

Good luck.
Ronco

[rb99]

About the Ebay water cooled spindles...

I only know hp not KW. How do they rate for hp?

Also how do you circulate the water?

As stated on EBay:"top quanlity item" :-)

RIB

[waynelocke]

Hp = watts/746

3000 watts spindle =4.02 hp

...I think

[jerry_stanek]

You use a aquarium pump and if you live in a cold climate you pump RV antifreeze to cool

[don62]

Gary, looked at the ebay site in your post and it seems tooooo good to be true. are these seconds? from midnight auto parts or what? have you or anyone else purchase from this group? thanks

[bill_lumley]

A friend of mine who is building a Mechmate is using this spindle at the moment . He fried the controller/spindle first time he fired it up because the speed was set too low .... no instructions ! They did replace it though free of charge . They come direct from you guessed it China !

[garyb]

Don, I don't stand behind or recommend this spindle, Ive had no experience with them except for the one that was on the machine that I went to work on.
I just posted the link, you're on your own the rest of the way.
My customer had no problem with his purchase and it runs quite well especially for the money.
They are new as posted.

Bill, I presume your refering to the power supply not the rpm that your friend failed to check before hotting it up. I'm surprised they replaced the VFD over that one but it does show the integrity of the company in standing behind their product even if it is from China.

[watswood]

Don, You may want to try the PreciseBits.com collets that Ronco recomended. I run a dual Z machine with a spindle and a Bosch router. For years I dismissed the Bosch as having inferior bearings and blamed it's slop on it's bearings until I tried the prcesion collets...I was amazed. I no longer have to put tiny little inlay bits in the spindle simply because it was more accurate than the router. They are pricy, but a relativly cheap experiment.

[erik_f]

Don, I've been playing around with trying to get more accurate with my machine. I just bought the Precise Bits kit that includes a 1/4" and 1/8" collet, nut, spanner, and collet care treatment for around $80 shipped. I also was able to find a test dial indicator with stand on ebay for $40 shipped. the test indicator is accurate to 0.0005". I figure it will be more that enough for my set up. From what I understand most of the run out is in the collets from Porter Cable not that actual router. I will try and test this when I get my new gear in. Pretty cheap over all and should hopefully improve my accuracy. The Precise Bits site has some pretty good info on it as well.

[bstern]

I have thought about the liquid cooled spindles because they eliminate warm up time. I sometime run a lot of on and off all day. I warm up each time the spindle is stopped for more than 15 minutes.

If anyone gives it a try, please keep us posted!

[coolhammerman]

Erik:
Merry Christmas! The photos above are projects I have made on your old PRT. I tweeked it some and did the G4 Gecko upgrade. The beefed up running gear and extra Y motor really make a difference, I think. I am still using the same PC router you had and couldn't be happier.

Hope things are going well with your Buddy ShopBot.

Ronco

[erik_f]

Thanks Ron. Merry Christmas to you as well. I am enjoying the Buddy...I do miss that nice big table. The dual Y motors really must be super nice with the G4 upgrade! I'm jealous of my old machine with G4
Glad the machine is working well for you. It seems you have it running very well. I always knew you would be able to do more with it that I was able to.

[coolhammerman]

Erik:
As you can see, I have very little trouble using cutters 0.492" (about 1/20" of an inch) and also have pretty good success using 1/32" cutters. This machine is very rigid and I'm convinced that the two Y car drives give it even more accuracy. I know lots of folks that tell me Bots are not capable of that kind of accuracy until they see what I produce.

All but the Masonic emblem actually has a female pocket and male inlay pieces. The Masonic emblem is just too small and I fill it with resin. The bright white stuff on the rest is Corian which is much harder than acrylic. The fit is so perfect that I usually have to set them into the inlay with a hammer after I apply a little thin CA glue.

At the same time, I'm making custom cabinets from 4x8 Oak Plywood. The ShopBot is an extremely versatile machine. It also helps that the fellow I work for owns 4 including 2 alphas and is somewhat of a ShopBot Geek. Whenever I try to do techno crazy stuff, I pick up the phone and he always has a solution.

BTW I purchased exactly the same precision collet package from Precice Bits that you did and It was really the right choice. I still don't have a dial indicator, but if it works, and it does, I'm getting the job done. I have an order for the new year for 24 Masonic pen blanks and will be using the 1/32 cutters a lot!


Ronco

[erik_f]

Ron,
A dial indicator isn't the same as a test dial indicator. You may already know this, but a dial indicator usually has a travel of 1" and something like .001" resolution. A test dial indicator has much less travel, but higher resolution. Travel is on the order of .030" with a resolution of .0005" to .0001". What I ordered was a test dial indicator with .030" of travel and a resolution of .0005". I figure for $40 including shipping and the adjustable stand, it was a pretty cheap way of curing curiosity and maybe I'll learn something to

[coolhammerman]

Erik:
I actually did not know that. So thanks for the info. If you haven't visited my web site lately, you should go to www.coolhammers.com (http://www.coolhammers.com). You will readily see evidence of Bot activity even if I don't point it out all of the time.
Ronco

[don62]

First, Merry Christmas!
Really appreciate all the contributions and thoughts in this thread. Having satisfactorily completed the project that started this thread, to the customers satisfaction, and having made no hardware changes in the process, I am now pondering the following data points:

1.

[erik_f]

you just have to check to see if all is tight. You may also want to check your roller bearings. If you are running a PRT...when I owned one, the z bearings had loosened up and I was getting play in the z. If you were going to spend 4k you might want to consider selling your bot and talking that 4k and buying a newer used PRS.