Best Router Model to Use?

[4DThinker]

The new HD 2.0 will use any of several routers available. I have the old Shark Pro that uses the Bosch Colt, but we are getting an HD 2.0 for the college shop I teach in.

Just wondering if you have an opinion on which of the different routers would be the most durable in a Shark. I've read previous posts on the cheap bearings that PC has been using.

So which of these would any of you recommend? My Colt is the only Bosch tool I've every owned. I've used (and worn out) several PC 690 series routers. I like the Dewalt router I currently have in my home shop. I know I want a variable speed model. Opinions?

Bosch 1617 and 1618
Porter Cable 890 series
Porter Cable 690 series (6902VS must be manually started)
Dewalt 610, 616, 618

Thanks

[jeb2cav]

I'm using the Bosch 1617 EVS. As you've seen, I think I'm finding the bearings wearing out 'faster' than with the 1hp Colt. From the discussion, I think any of these larger routers will have similar outcome - less from cheap bearings and more from the larger bearing associated with these larger routers are not rated to run continuously for several hours at a time.

So while I don't know if this is the case, that is my intuition. If someone can get the bearing info for the other routers and share that, BillK or one of the other bearing experts may be able to give some additional info on the bearing aspect to help you decide.

2013 will probably see me moving to a spindle of some sort - still looking at that. I do use the 1hp colt for a lot of 3D work on the HD as there is no advantage for some of the complex 3D work I create with the larger router.

[4DThinker]

Thanks Joe. Still curious what opinions others have. I just ordered the big Bosch 1617 as Amazon has $25 off on the rather low price for them right now. My dept. will be ordering a PC 892 for the HD 2.0 and I've order PrecisionBits' upgrade collet for it. I plan on starting with the PC and logging the time it runs. When it fails for whatever reason I'll stick the Bosch in there and do the same. At least I'll then have some data for two models. This HD 2.0 we expect to be heavily used by a variety of people including several professors as well as 30 or more students in a semester. Big experiment to see how a Shark survives in that environment.

I'm hoping someone can come up with a replacement bearing spec that IS rated for lengthy CNC runs. It would be nice if NWA had a recommendation.

If you come up with a spindle you like that is an easy upgrade to the Shark then let us know. Our HD 2.0 hopefully will last 10 years or so until I retire, but we are not averse to significantly upgrading it over time.

Anyone else with a router preference?

[4DThinker]

Boy, I shouldn't have searched the web for info on the 890 series router. Apparently a recall in 2006, ongoing heat and failed bearing complaints, etc., mixed in with reviews from people who love theirs. I got fed up with Porter Cable last semester because none of the 690 routers we had would center a bit in the bushings for my PC dovetail jig. Ended up using an old Dewalt with the jig.

Wondering if new Dewalts are made any better than the Porter Cables. Do all these motors come from the same factory?

[Eagle55]

I'll put a little bit of information out and maybe the accumulation might help. I have PC690 set up in my HD machine. I am about to wear out the second set of bearings (second router) so in other words original bearings in two PC690's. I have heard feelings that Bosch might be a better built router, but since I had started my Precise Bits collet collection for the PC I really didn't want to switch and have to buy replacement collets. I also have the larger PC router in my table (7518 or what ever it is). I am going to get bearings and become skilled at the replacement procedure but have temporarily put a band aid on the situation by getting the PC890. I realize that they have had some past problems but gosh 6 years after the fact I'm not sure if I should still be worried about that issue. Surely they have clean up the mess by now. My hopes are that the variable speed feature will allow me to cut at slower rpm and be easier on the bearings long term. I stayed away from the 690VS because of the funky on/off ?safety? feature. I just can't stand it when safety feature get so obtrusive as to make you start to do unsafe things to get around them. I may also fix an adapter to use the colt on some stuff although I use my Colt a lot on the bench and don't really like the idea of being without it and even less buying another one at the moment.

Not a lot of well rounded experience, but at least tells you where I am at the moment.

Roger

[BillK]

I have about 30 years experience with bearing of all types from aerospace, railroad, automotive, etc. Here's a few points you need to consider about router size and bearing life:

1. All bearing have a "limiting speed" a rule of thumb is that that speed is based on roughly 5,000 fpm (FEET per minute) of the rotation of the pitch circle of the balls in a greased bearing. The larger the bearing, the slower the rpm (revolutions per minute) as one revolution covers more distance than in a smaller bearing.

2. If the bearing has a rubber seal, as most router bearings have, that speed can be cut down even further depending on the fit of he seal, sometimes as much as 50%.

3. Larger routers have more horsepower and larger bearings. So if you are doing heavy milling of shapes where you want to take a deep cut at a relatively fast feed rate with a large bit, use the large router.

4. Small routers like the Bosch Colt have small bearings which can withstand longer run times at higher speeds. This is ideal for your 1/16 ball end mill with the .005" stepover and .015 depth of cut. You need a higher speed for that cutter but not so much in the horsepower category to take care of those small amounts of material removal.

So your router choice should be based on what type of cutting you will be doing. With high rpm and long cut times, expect to wear out bearings in your large router. Take heavy cuts with large end mills with your small router and expect poor results. It really comes down to the type of cutting done and the bearing size of the router to determine the bearing life.

[4DThinker]

Thanks for your post, BillK. "Pitch Circle" and 5000 fpm is a tempting bit of info. Makes me wonder what this value relates to on an actual bearing that would be in the Porter Cable or Bosch routers. At 23,000 rpm (rated top speed) and maybe a 1" pitch circle for the bearing my math wants to claim (3.14" x 23,000)/12 = 6018.33fpm. I don't know the actual pitch circle, but if it was 1" this suggests that slowing down the router to 19,000 or so would put the fpm under 5000, and perhaps make a significant improvement in their duration. We normally run our Multicam spindle at 18000 rpm, based on similar advice from the Multicam technician who trained us on it. It uses ceramic bearings.

If this theory is correct, the important data needed is that pitch circle value for these routers. Anyone have that info?

BillK was nice to link me to some info on bearings. I also have a parts diagram for the Bosch. It uses what looks like a .75"id bearing with 1.1875" as the pitch circle diameter. The bearing matching that size does show 23,000rpm as the recommended speed limit. At 23000rpm the fpm is 7147, a bit above the 5000fpm suggested. Working backwords I get 16091rpm as 5000fpm.

The bit used, feed speed, spin rate, duration of cut, and material density all play a factor in how hard it is on the bearings when running in a CNC machine. So only generally is it safe to say that a slower rpm, when otherwise feasible, would result in longer life of the bearings used. It would be nice to set up two identically configured Sharks side by side with the only change between the two being RPMs run at. Limit one to 16000 and run the other at 23000. Log hours used on both.

If only I had two Sharks.....

[Scottart]

I have The Dewalt 618. I run it every day up to 8 hour shots, since November. I am no machinist so really could not comment on it's quality, it just runs and I have had no problems. I would be interested in the noise level of other units, but can't really comment on how long this unit might hold up.

[SPH01]

I have two of the 1617EVS, (you will need a spare) I may be wrong but I think the NEW 1617EVS have the safety feature that they will NOT turn on using the control box. Power switch has to be cycled in order to reset the router from a "power outage" for safety reasons. (this may be a new rule coming out, not sure). Like others on here I gave up on the router and went water cooled spindle. 90%less noise.
If you run a router (any router) do not run it a full speed and you will notice it will last 2x longer. I run my Bosch at 5 not 6 and it makes much less noise and the bearings last much longer.
Good luck.
Steve

[4DThinker]

We put the PC 892 into the HD 2.0 we have. I noticed the default rpm for most bits in the tool database was 16000 so I've got it set there and it has been fine with the few jobs we have run so far. It is surprisingly quiet at that speed. We raise our voices a bit but do not need to shout to hear each other while it runs.