Bosch trim router speeds

[jamomer1]

I have an older Bosch trim router mounted on my CNC. It has a speed dial with numbers 1-5. I think the max speed (5) is 33,000 - but what speeds are the other 4 numbers? I cant find it anywhere.

[litzluth]

There are plenty of freeware applications you can use to measure the frequency of an audible sound (or use a frequency counter if you happen to have one).
Then you can use this converter to calculate the rpm of the router from the frequency it is emitting.
https://thistothatcalculator.com/rpm-to-hz-calculator/
As an example, the router frequency at 33000 rpm is 550 Hz. 233 Hz at 14000.

[TReischl]

That sounds a bit fast for a router. Usually they top out at around 25K. I have never seen one much above that, but then I have not seen everything yet.

The bottom end on most routers is around 12K, otherwise they have zippity doo dah torque. Well, they have very little at 12K actually.

So I would subtract one from the other, divide it up by the total minus 1 and then start adding to the bottom number. Get ya in the ball park anyhow.

BTW, I run a full size Bosch router and I typically run it at the lowest speed setting. Create more what looks like chips that way.

[FabLab Wageningen]

I second Ted. 33.000 sounds a lot.

We have a DeWalt with 6 speed settings, from about-ish 14.000 till 25.000, We rarely go over 18.000 anyway.

Marcel

[Rcnewcomb]

It depends on the model.
From the Bosch manual: the PR20EVSK has speeds from 16,000 - 35,000

Therefore, my guess would be:
1______16,000 RPM
2______19,167
3______22,333
4______25,500
5______28,667
6______35,000

[TReischl]

It depends on the model.
From the Bosch manual: the PR20EVSK has speeds from 16,000 - 35,000
.......

That sounds a bit fast for a router. Usually they top out at around 25K. I have never seen one much above that, but then I have not seen everything yet.
......

Welp, now I have seen some more!!!!

[adze_cnc]

Interesting that it says "no-load RPM" max of 35,000.

How much does it drop when you insert a bit? When trying to skim off 1mm of material...2mm..?

[4DThinker]

Interesting that it says "no-load RPM" max of 35,000.

How much does it drop when you insert a bit? When trying to skim off 1mm of material...2mm..?

The router doesn't sense the load on the bit, and is rated at 1.0hp. How much drop in speed would vary with the size of bit used and depth of cut and material being cut.
BTW although the router will run at 35,000rpm I found keeping it set on 4 rather than 6 would make them last longer on a set of bearings. Only small diameter bits (1/16", 1/8") would be worth running at 5.