Wood router duty cycle?


I am considering to use a Bosch Colt wood "palm router" (or even a
bigger wood router) as a high speed spindle for milling small detail
on my CNC mill.
Kind of like this:
formatting link

When I talked about it somewhere, somebody said that it cannot survive
this for long due to poor cooling, and that it will never have the
duty cycle as needed on a CNC machine.
For me, say, 4 minutes on/6 minutes off would probably work out okay,
as the speed of the cutter enables me to complete typical milling jobs
quickly.
But still, the duty cycle question is important.
So: what do you think is the duty cycle on these and how much could
they take before they overheat?
i
Reply to
Ignoramus12820
Loading thread data ...
Ignoramus12820 fired this volley in news:34WdnVDmwp7NufDRnZ2dnUVZ snipped-for-privacy@giganews.com:
I know that the head on one of my vendors' CNC router - by itself - cost over $700.00. It is rated for 5000 hrs continuous duty at 45KRPM before requiring a bearing overhaul -- which is a factory-only job.
They claim it's good for five re-builds, minimum, if the chuck is never crashed into the work.
This "head" isn't a router in the conventional sense. It's just a motor with mount pads and a collet-style chuck on a fairly short shaft. Nothin' much to look at. But it's virtually silent running at 40K under no load. It runs on a dedicated speed controller, and is purportedly a multi-phase motor. The controller was extra $$, and misbehaved badly for speed regulation and control until swapped out twice by the factory rep.
Don't remember the brand, but it's the one the ShopSabre folks recommend for the machine.
LLoyd
Reply to
Lloyd E. Sponenburgh
I would guess that 4 minutes on and 6 minutes off would be no problem. Not familar with the Bosch but I think all routers have a cooling fan.
Dan
Reply to
dcaster
Should only cost you about $100 to find out, buy one and see how it holds up.
Reply to
Leon
Probably ok for continuous shallow duty. Notwithstanding, for 100 bucks how can you go wrong? You have 10x that in the holder/bracket and that great camera. Don't sweat it; if it blows up get a PC 690, known to run forever at medium duty levels. ***************************************************************************= *******************************
formatting link
Router Woodworking *******************************************************************
Reply to
routerman
Why not use a Speeder? One of those BP doo-hickeys that uses gears and belts to triple the spindle speed.
Reply to
Mike Henry
...
Somebody is talking out of somebody's rear orifice. While you're not generally going to find one at the business end of a $100,000-$300,000 commercial CNC machine, where a $5000 spindle motor is not a big expense, tens of thousands of $2,000-$15,000 homebuilt or kitbuilt CNC routers run them with no particular problems.
Other than being LOUD due to the universal motors, quality wood routers can be used rather extensively. If you can arrange to feed it clean air (possibly force-feeding it - ie, put a duct and blower on it), so much the better. If you actually service/replace the bearings per schedule (IIRC Porter-Cable specs 100 hours on the 690) better yet.
CNC wood router folks have used them for quite a while - the folks with money do like to step up to much more expensive and powerful (and quieter) spindle motors, but in bang/buck the router does fine. I've run mine for hours at a stretch, and so have a lot of other folks with CNC routers. Even if you simply run it til it dies and replace, the bang/buck is good, but servicing it properly the bang/buck should be better.
Unless you have a specific need for the small size, pick a normal router over a laminate trimmer/palm router/whatever.
A 690 mounts nicely to a chunk of channel with a big hose clamp, by the way. Just take the base off.
Crapsman, B&D need not apply...
Get good, comfortable hearing protection - you'll need it.
In (non-cnc) router table service, it's not uncommon to switch one on and run hundreds of feet of molding though a router, so running them for hours at a stretch is not some oddity that only CNC router folks do. The cooling air on a 690 makes one heck of a breeze...
Reply to
Ecnerwal
I did not find any speeder that would cost what I can pay and would fit my spindle in some way (NMTB 30 or straight shank). Otherwise a speeder would be nice.
i
Reply to
Ignoramus12820
Yes. I was thinking about it as I was walking to work.
I realized that, say, 30,000 RPM is not that big of a deal for a small spindle on this Bosch Colt. It is not like it is a 2.5" Bridgeport spindle with huge bearings and huge linear speeds. The spindle bearings are probably 3/4" ID or there abouts.
The manual on it calls for a factory rebuild (read bearings replacement) every 300 to 400 hours.
If I can get 300, or even 200, hours out of it, this is all I really need. It is a lot of hours for a hobby use. Considering that a very fast head like this can complete projects very quickly due to high feedrates possible, 200 hours could complete a lot of projects. Similarly, because it works so fast, it would not need to stay running for very long, before it completes the assigned task.
I thought for a moment yesterday that I will use my big 2.5 HP router, but I am backing out of this, it is a little too big and there are complications with overhang, etc that would impact accuracy too much. Plus it is inconvenient to mount.
This Bosch Colt looks very appealing, because of ease of mounting, reasonable power, etc.
I think that I could use it with a 10A solid state relay, because, IIRC, it has a soft start.
Here it is 300 hours. Not really a problem.
Just what I hoped to hear.
What about something like this:
formatting link
I think that it can be taken out of the base and then mounted in some kind of a round clamp. I have a CNC mill, so I can make an aluminum clamp that fits perfectly.
690 is something like this, right:
formatting link
That could also work. Any comparison with the Bosch one?
yep
Well, that is very nice to know right from the horse's mouth, so to speak.
thanks
i
Reply to
Ignoramus12820
You have compressed air available and the router will be fixed on the machine, so just adapt it for forced cooling air. Fabricate a manifold to introduce the cooling air (via a filter and a throttling valve) to the top intake of the router. You'll benefit both from the cooling action of the decompressed air, as well as a clean air source.
Reply to
Pete C.
You know Pete, this is a good idea. It definitely needs a good filter, but it is a great suggestion. It may be that I can find a "turbine" for paint sprayers that would deliver more air at the pressure that I need, as opposed to a compressor.
After a lot of thinking, etc, I have decided to bite the bullet and bought this Bosch router:
Bosch 1617EVS 2-1/4 HP Variable-Speed Router
formatting link
It is only marginally more expensive than Colt, and should be trivial to mount in a clamp, due to its round body. The speed range of 8,000 to 25,000 RPM is also ideal for me. Soft start is also a huge plus. It comes with a 1/2 and 1/4" collet.
i
Reply to
Ignoramus12820
How about this one
formatting link
. I Don't know what it would cost to ship to the US or if any US firms stock it already.
Reply to
David Billington
I know of a few CNC's (General Gorilla) that use those 2.25HP (1/2" shank!!!!) Bosch's in school settings. Aside from the noise, they're holding up very well. Shopbot also sells a 3.25 HP universal motor PC router body that also seems to run quite well.... but they do offer rebuild-kits matter of factly. I run an Elte 3HP 3phase spindle off a VFD and it runs quietly and full power at any speed....and cool.
Reply to
Robatoy
I have put 100's of hours on a PC 690, used for wood as well as high density polyethelene (hdpe) with 1/2" diameter bits running 3 inches/ second (60% cut, 1/4" max depth per cut).
Wore the brushes out, replaced them from the ShopBot spares kit, original bearings still working just fine. The dust collection does pull the exhaust air from the collet end (the only danger I saw was the sparks from brush end of life and fine sawdust mixing ... no fires or explosions, thank you very much.
I tend to run the 690 on the middle of the 5 available speeds ... no noise reduction, just adjusted everything for shavings per bit manufacturer.
Hope this helps.
Rick
Reply to
Rick
I used to work in a place that used router tables to trim plastic. The routers were working continuously for up to three hours at a time. Only thing they ever needed was normal bearing replacement. Porter Cable 690 routers.
Reply to
CW
Iggy, This maybe a bit off-topic, but NMTB30 is very popular in Europe, as opposed to R8, which isn't. It appears that it is exactly opposite in the states. You may find tooling hard to find and expensive there. If shipping is an issue, contact me off-line perhaps I can help. Steve
Reply to
Steve Lusardi
I see the router setup to be a better way to go. The referenced speeder is rated for only 9000 rpm output. Most newer CNC mills will do 10000 stock. Another is that is a kit.
Reply to
CW
Good to know. I will use a Bosch router that can be easily mounted inside a round clamp.
i
Reply to
Ignoramus12820
to R8, which isn't. It appears that it is exactly
If shipping is an issue, contact me off-line
Steve, it is not that hard to find, but I could not find any decent affordable high speed spindle in NMTB30.
i
Reply to
Ignoramus12820
Seems like some kind of a homemade contraption to me.
The router would go from 8,000 to 25,000 RPM.
i
Reply to
Ignoramus12820

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.