Measuring speed - OF1400 speed

[bobtskutter]

I just thought I'd post a quick piece about how I measured the rotational speed of my OF1400 router.

I used an Android phone Spectrum Analyser app to display the frequency of the sound generated by the router with no bit installed.
There were specific frequency peaks as a changed the speed dial from 6 to 1.

6 = 363Hz => 21780rpm
5 = 322Hz => 19320rpm
4 = 275Hz => 16500rpm
3 = 243Hz => 14580rpm
2 = 193Hz => 11580rpm
1 = 167Hz => 10020rpm

To convert from Hz to rpm: 363Hz x 60 = 21780rpm.

The numbers match pretty closely to 10,000 - 22,000 /min number on the Festool name plate of the router.

Now...onwards to the other Festools in the collection.

regards
Bob

 

[festal]

Nice. Thank you

 

[Cheese]

Thanks for posting that info  [smile] just nice to know.

A few years ago I plotted the router speeds on my 1010, 1400 & 2200 routers. I had to assume that the speed control was linear and I simply divided the speed range by 6 and after some whole number rounding and Kentucky windage, I arrived at these speeds for the 1400.
6 = 22,500
5 = 19,500
4 = 17,000
3 = 15,000
2 = 13,000
1 = 10,000

I like your method better.  [cool]. Also interesting to note is that at max speed the 1400 is 700 rpm below its rated speed of 22,500.

 

[Sparktrician]

If you're interested in a precise speed, you might want to use a StroboTach.  Back in the days of iron men and wooden ships, we used to use something quite similar for checking shaft speeds on the ships.  [smile]  (There are other less spendy options at the bottom of the referenced page.)

 

[Bob D.]

How accurate are those cheap photo tachs that use reflective tape on Amazon? They are less than $30.

 

[GarryMartin]

These are the numbers I posted using a laser tachometer back in 2014. Obviously you have to account for some variability based on how accurate you can position the dial in relation to a specific number, but you'll find it's a *very* linear progression through the speeds.

Speed Setting 1  -  10000 RPM
Speed Setting 2  -  12400 RPM
Speed Setting 3  -  14800 RPM
Speed Setting 4  -  17200 RPM
Speed Setting 5  -  19600 RPM
Speed Setting 6  -  22000 RPM
https://www.festoolownersgroup.com/ask-festool/of-1400-speed-control/msg297916/#msg297916

 

[woodbutcherbower]

Maybe I’m missing something here. Why would anyone want to know the exact rotational speed of a router cutter?

35 years on the tools as a pro, and it’s never been something I’ve thrown a microsecond’s thought at. Please explain.

 

[peter halle]

Maybe I’m missing something here. Why would anyone want to know the exact rotational speed of a router cutter?

35 years on the tools as a pro, and it’s never been something I’ve thrown a microsecond’s thought at. Please explain.

The speed comes into play when you start using larger and larger bits.  Generally speaking their operating speed should optimally lower.

Peter

 

[Willy Eckerslike]

I'm with Butch on this one.  Accepted, larger cutter slower speed but given that the speed dial doesn't have stops, it just rotates from fast to faster and nothing else is governed during use such as quality of cutter, feed rate/rate of travel, depth of cut, or type/density of material, why do you need to know the exact rotational speed when everything else is so vague?

 

[Cheese]

Maybe I’m missing something here. Why would anyone want to know the exact rotational speed of a router cutter?

It's a general reference for a starting point...I wouldn't exactly call a 2000 rpm range exact...just a reference point and I treat it as such. I have a cheat sheet that gives the maximum cutter revolutions for various diameter cutters based strictly on the engineering data that was used to prevent a catastrophic event.
The data lists general diameters so again, they're just a starting point:
Under 1"
1" to 2"
2" to 3"
Over 3"
So its just a quick place to begin and then fine tune it from there.

It's not unlike looking at the speeds available on a drill press and then setting the speed in accordance with the diameter of the drill bit.

Same thing with a band saw and setting the band saw blade speed accordingly for the type of material it's cutting. 

 

[woodbutcherbower]

I'm with Butch on this one.  Accepted, larger cutter slower speed but given that the speed dial doesn't have stops, it just rotates from fast to faster and nothing else is governed during use such as quality of cutter, feed rate/rate of travel, depth of cut, or type/density of material, why do you need to know the exact rotational speed when everything else is so vague?

Exactly. Every other aspect of cutting with a router is dependent on all of this - not just the cutter speed. Notwithstanding what Peter Halle said, huge cutters have no place in the collet of an OF1400. Many years ago and being pushed for time, I stupidly put a panel-raising cutter into my OF2200 instead of spending time setting up my spindle moulder - and yes, the 2200 was set to a low speed. The outcome scared me half to death. A few hundred rpm wouldn’t have made that experience any more pleasant. It’s not just coincidence that above a certain diameter, the Trend catalogue stipulates ‘THIS CUTTER MUST ONLY BE USED IN A STATIONARY MACHINE’.

 

[Crazyraceguy]

There are quite a few variables involved including the feed-rate of the material, type of material, and depth of cut too.
It is just as possible to go too slow as it is too fast. The cut quality suffers with both, just in different ways. The exact number, not overly important, but it does at least give you a starting off point.