[Bob La Londe]

I started using a Bosch Colt as a spindle router a while back. The first couple I got quite good life out of running 750 and 900 hours respectively. I would check the brushes and replace them as needed, but the bearings did quite well. I would see finish issues before they would start to get so hot that they would damaged anything. I figured I would just replace bearings every 500 hours and not worry about. No such luck. The newer ones started failing catstrophically at only 200 or 300 hours. One at only about 150. The difference in finish and bearing over heat would occur quite close together and melt the nylon insert in the router before I could stop the machine and replace the bearings. Once that's melted its quite difficult to dissassemble the router so I just have to replace it. I've gone through more than a couple of Bosch Colt Router. I think I have five of them on the bone pile right now.

Anyway. I have decided the Bosch Colt is not up to the agressive cutting I am doing, and I am ready to look at something better. I don't really need more power because I am working with cutters from .0625 to .125 most of the time, but I am pushing the maximum load on the cutters. I guess what I need is a spindle that can turn fast like that and hold up to the side load on the bearings as it cuts. (I do bog the motor once in a while on a plunge cut)

I'm not against buying one of the Chinese import VFD controlled spindles. I already have a 220V circuit on that wall I could use. I could get by with only the 24000 max RPM they advertise, but I don't want to spend several times what a wood regular wood routers costs if they won't hold up any longer running at their max speed.

On an aside from that. Are there any regular wood routers out there in similar size and spindle class that would make a better quality longer lasting replacement for the Bosch Colt. Slightly bigger would be ok but like I said I don't "need" more horsepower.

One of the issues I think with the Bosch Colt by the way is that the front main bearing is "insultated" by the nylon bushing it presses into. If it were pressed into an aluminum bushing it would transfer heat away from the bearing better and it would loose tolerance before it overheated more consistently. I had considered making my own bushing, but then the cost in time over weighs the savings in the router. This leads me towards looking at one of the import water cooled spindles. The back bearing has no more play in it then a new one when the front bearing fails. So its obviously the side load from milling that causes it to fail and heat up.

All of that not withstanding I also considered making my own spindles and using an external motor of some kind, but the array of available bearings is dizzying and I wouldn't have a clue where to start to select an strong high speed bearing for the application.


Summary:
Import 3 Phase VFD controlled spindle - Life under load with aggressive cutting?

Off the shelf router as spindle - something substantially better than the Bosch Colt?

I can make my own mounts anyway I go.

[Bob La Londe]

I must have posted in the wrong area or something.

Anyway, I just finished making a mount for a PC 690LR on this machine. I'll be sure to post back with a progress report as informative as all the help I got here... LOL.

Seriously is does seem a lot more robust than the Colt, but the bearings do not impress me so much. We will see. I'm goign to be setting up an 8-10 hour job on it shortly in aluminum.

[jimmyaz]

What about this?

It worked well for me, Dewalt got variable speed and governor geared 2-1, plenty of torque.

[Bob La Londe]

What about this?

It worked well for me, Dewalt got variable speed and governor geared 2-1, plenty of torque.

I considered doing something similar to that using a straight shank ER16 tool holder as the shaft of a home grown spindle.

How many hours do you have on your assembley?

What kind of material are you cutting?

What is the combined weight of your spindle, spindle mount, motor mount, and motor?

P.S. Very nice looking setup.

[jimmyaz]

I cut mostly FRP G10 or 6061 aluminum. About 50hours on g10 and 10hours in aluminum. Haven't discover any wear or slop on the bearings yet and they are just average bearings.

It's quite heavy, I estimate probably about 20-25pounds.

[RTP_Burnsville]

Have you taken a look at routers from Hitachi? One of the local stores just started handling them and they look very nice. In the past I have typically bought Bosch, but I think that may change on my next purchase.

Robert

[Bob La Londe]

Hitachi's motors used to be built by one of the big motor makers back when I was in the tool business, but I had heard they had gone to one of the chinese mass production shops a few years ago.

[ger21]

I must have posted in the wrong area or something.

Anyway, I just finished making a mount for a PC 690LR on this machine. I'll be sure to post back with a progress report as informative as all the help I got here... LOL.

Seriously is does seem a lot more robust than the Colt, but the bearings do not impress me so much. We will see. I'm going to be setting up an 8-10 hour job on it shortly in aluminum.

If you're taking a brand new 690, and running it at 27,000 rpm for 8-10 hours, you may be asking for trouble. I'd think some breaking it might be beneficial?? It's not designed for that kind of use.

As for the bearings, they're only about $15 for both.

I use a SuperPID to control the rpm on mine, and have run it for 12 hours a few times, but at 12,000-15,000 rpm, which keeps it much cooler. And it's 15 years old.

[Bob La Londe]

If you're taking a brand new 690, and running it at 27,000 rpm for 8-10 hours, you may be asking for trouble. I'd think some breaking it might be beneficial?? It's not designed for that kind of use.

As for the bearings, they're only about $15 for both.

I use a SuperPID to control the rpm on mine, and have run it for 12 hours a few times, but at 12,000-15,000 rpm, which keeps it much cooler. And it's 15 years old.

So you are saying the PC 690LR is LESS robust than a Bosch Colt?

Wow! I guess I'll just throw it away and go back to the smaller lighter router. LOL.

[Phife]

So you are saying the PC 690LR is LESS robust than a Bosch Colt?

Wow! I guess I'll just throw it away and go back to the smaller lighter router. LOL.

lol, ya just throw that thing away.. you sound like you have money to spare!

Since you seem to like to spend money why dont you just buy a 0.8KW water cooled spindle from ebay with a VFD and be done with it?

[Bob La Londe]

lol, ya just throw that thing away.. you sound like you have money to spare!

Since you seem to like to spend money why dont you just buy a 0.8KW water cooled spindle from ebay with a VFD and be done with it?

Money to spare? No. Hence why I asked here before getting anything. The lack of response led me to "just try something."

I would get a variable speed spindle off ebay if anybody could answer real world working questions about them in terms of life under full load, and service intervals. No point if I find out I have to rebuild them every hundred hours.

I get a couple hundred hours out of a Bosch Colt at 30,000 RPM at pretty good side loads. If I could more accurately predict bearing failure I would just keep using them. The only thing that goes wrong with them is bearing failure and brush wear. The problem is really only when the bearings fail to quickly to replace before they take out the nose of the tool.

[RomanLini]

If you are using high RPM like 30000 then routers will probably give better performance than a VFD spindle. The router peak power is at the high RPM end of the curve, where VFD spindles are a bit like stepper motors, their power drops off at high RPMs, and many VFD spindles are useful only into the low to mid 20k RPM zone, and even then will have a lot less power at >25K than a large router.

As for the SuperPID speed controller, it's probably not needed if you are only using RPM 25k to 30k, as that is the routers peak powerband and the router will have a ton of power there even without a sophisticated controller. But the SuperPID will allow much more power in the lower RPM zone (like 12k to 15k as Ger21 said he uses) and that reduced RPM will greatly increase bearing and brush life, and likely increase tool life too depending on the tool and material.

[Bob La Londe]

If you are using high RPM like 30000 then routers will probably give better performance than a VFD spindle. The router peak power is at the high RPM end of the curve, where VFD spindles are a bit like stepper motors, their power drops off at high RPMs, and many VFD spindles are useful only into the low to mid 20k RPM zone, and even then will have a lot less power at >25K than a large router.

As for the SuperPID speed controller, it's probably not needed if you are only using RPM 25k to 30k, as that is the routers peak powerband and the router will have a ton of power there even without a sophisticated controller. But the SuperPID will allow much more power in the lower RPM zone (like 12k to 15k as Ger21 said he uses) and that reduced RPM will greatly increase bearing and brush life, and likely increase tool life too depending on the tool and material.

I have been running the PC690 router for a while now. Just finished a 3 hour roughing job with it. It is definitely a lot more rigid than the Colt. I could see it in the lack of chatter marks in the more aggresive cuts. Also, the spindle collet and nut are only warm after running continuously for 3 hours. Not even enough that you might notice if you weren't checking things like that.

Anyway, thanks for your feedback. With small cutters the high speeds are really the only option for cutting to get decent material removal rates.

Its doing what I suspect will be about 6 hours of light finish cuts right now with a .0625" cutter.

[jm82792]

It's incredibly painful that things are not made they way they used to be, some of my father's powertools are older then I am and still run great.

[Bob La Londe]

I've got about 36 hours on the PC690LR now. Some taking light cuts continuous and some take moderately heavy cuts continuous. The spindle nose bearing definitely runs a lot cooler than the Bosch, and its definitely more rigid as shown in the much lower incidence of chatter marks on the heavier roughing cuts.

I even took some rather aggressive cuts with smaller cutters (.0625") and it performed very well. I think the better rigidity really made a difference there.

[cyclestart]

What about this?.

Nice !!
Small belt drive router spindles show up on ebay but I can't recall seeing one that size.

[LazyMan]

I know that the Chinese spindles are rated to 24,000 rpm but I would avoid running much more than 18,000. Precision steel bearings wont due well at much higher RPMS because they overheat. Take a look at all the "real" spindles like columbo; anything higher than 18000 uses ceramic bearings. Then again, those Chinese bearings really are not precision.