# Feed speed.



## Artemix (Aug 10, 2014)

I wonder, what could happen if my router feed speed is too high?.

I had to do several notches and I just increased the speed, and despite hearing my router lower it's RPM, didn't notice any problem.

What's your stance about this?.


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## DonkeyHody (Jan 22, 2015)

If you increase the feed rate, the bit has to take a larger bite with each half-revolution. Cut quality will be lower and chances of chipout will be higher. With 1/4" shank bits, the chances of breaking a bit are higher. What's the hurry?


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## Stick486 (Jan 4, 2013)

meet the speed to the need...
save the bit and don't destroy the router...


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## Artemix (Aug 10, 2014)

I will provide more info:

- material: MDF
- notch: 0.23x0.23", square
- router bit: straight router bit, 3/4" diameter 
- RPM: 20k RPM approximately
- speed: I'd say to finish 35" it takes more or less 15 seconds if I go fast.

The finish seems to be the same, going slow or fast, I don't smell any burnt wood (or MDF in this case), I only notice that there is a mild vibration like sound, that I suppose its coming from the speed.


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## Stick486 (Jan 4, 2013)

the vibration is coming from taxing the equipment...


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## Artemix (Aug 10, 2014)

Is it unsafe?, it is a Dewalt DWP611PK.


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## Cherryville Chuck (Sep 28, 2010)

A 3/4 D bit is a relatively large bit for that router although you aren't taking a large cut. One of the risks of slowing the motor down too much is that it causes the amperage draw to rise which also creates heat. Heat is bad for electrical windings and worse for electronic circuits. That's the risk but without hooking up an amp meter it's hard to tell when you reach "too much". The vibration is also bad for the router so if the router didn't vibrate on the earlier, slower cuts but it did with the more recent faster cuts then I would say you are trying to go too fast.


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## hawkeye10 (Jul 28, 2015)

I have this chart taped to my router table and I use it. If you follow the the manufactures guidelines for speed you be safe, your bits will last longer, your router will last longer, and cut quality will be better. Like "Donkey Hody" said WHATS THE HURRY?


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## mgmine (Jan 16, 2012)

The problem with speed is how do you measure it? Sure the router may have a knob or something that gives you a number but what does it mean and how accurate is it? I seldom change my speed and I don't have any idea of what I have it set at. I listen to it and if it sounds like an airplane propeller 
which large panel bits can make it sound) I slow it down. From what you describe *"I just increased the speed, and despite hearing my router lower it's RPM " * it sounds to me like the router was going to slow to start with. Unless I'm not reading it right you are taking less than 1/4" off in a pass. You are not taking much off, mdf is soft so I wouldn't worry about it. But how are you making a 1/4" notch with a 3/4" bit?


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## Artemix (Aug 10, 2014)

WIth speed I meant the speed of the wood I'm moving through the bit, sorry for the confusion.

Also, Chuck, my shaft is actually 1/4", only the cutting part is 3/4". 1/2" will also do, after all my cut is only ~1/4".

About using a larger bit to make a smaller notch, is that a bad practice?. I can change it for a 1/2" bit if needed.


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## DonkeyHody (Jan 22, 2015)

Artemix said:


> Also, Chuck, my shaft is actually 1/4", only the cutting part is 3/4". 1/2" will also do, after all my cut is only ~1/4".
> 
> About using a larger bit to make a smaller notch, is that a bad practice?. I can change it for a 1/2" bit if needed.


If a larger diameter bit and/or one with a larger shank will do the job, then I believe you should use it. Here's why:
1. With a larger diameter bit, the cutting edge exits the wood at a shallower angle. This may not be too much an issue with MDF, but with woods prone to chipping, you'll have less problem with chip out. 
2. With a larger diameter shank, the shank is more resistant to deflection. Shank deflection leads to vibration, (sound familiar?) rough cuts and broken bits.


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## Cherryville Chuck (Sep 28, 2010)

I knew what you meant Pablo, I have that same router. I thought about your size question and I'm not sure of the answer so try it and see. The larger bit has a faster linear rim speed than a smaller bit but any resistance to the cut also applies a longer torque moment against the routers speed.

To make that simpler imagine taking a 2.5m board and make it pivot .5m from one end. If you push on the short end the long end will move 4 times faster but I could easily stop it because I would have 4 x the mechanical advantage over you. Put me on the short end and I couldn't possibly stop you. It is easy to overwork a router with a large diameter bit and hard to overwork one using a very small diameter bit so just be careful going fast with that 3/4" bit in the router is what I suggest.


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## Herb Stoops (Aug 28, 2012)

I do it all by sound and feel, When I turn on the router ,I set the speed of the bit by the sound of the of the router, and when I feed it I can feel the limit of how fast to cut and hear the motor working.

Herb


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## Stick486 (Jan 4, 2013)

mgmine said:


> The problem with speed is how do you measure it? Sure the router may have a knob or something that gives you a number but what does it mean and how accurate is it?


you need to open and READ the PDF's...


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## mgmine (Jan 16, 2012)

Stick486 said:


> you need to open and READ the PDF's...


Okay I read the feed and speeds but I have no idea on how I would ever remember such a vast amount of information. For me it's all about sight and sound. If it looks right and sounds right it's right. Sort of like shifting the gears on the car, or pushing wood through the table saw or running a welding bead. Do it a few times then muscle memory takes over.


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## Nickp (Dec 4, 2012)

Stick486 said:


> meet the speed to the need...
> save the bit and don't destroy the router...


WOW...what an eye opener...I looked at the 1617 chart (Hardwood) and, if I read it right, a 1/2 bit at 16500 RPM should see a minimum feed rate of 10"/sec... (627 IPM). 

15.8"/sec if cranked up to 25000RPM...

After a good meal, I can't walk that fast...


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## Stick486 (Jan 4, 2013)

mgmine said:


> Okay I read the feed and speeds but I have no idea on how I would ever remember such a vast amount of information. For me it's all about sight and sound. If it looks right and sounds right it's right. Sort of like shifting the gears on the car, or pushing wood through the table saw or running a welding bead. Do it a few times then muscle memory takes over.


print the basic chart...
study it...
refer to it often as you teach yourself muscle memory...


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## mgmine (Jan 16, 2012)

Stick486 said:


> print the basic chart...
> study it...
> refer to it often as you teach yourself muscle memory...


Too late the muscle memory has been ingrained for over half a century.


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## Moz (Nov 13, 2015)

hawkeye10 said:


> I have this chart taped to my router table and I use it. If you follow the the manufactures guidelines for speed you be safe, your bits will last longer, your router will last longer, and cut quality will be better.


Oh AWESOME chart!
It is made to place the bit next to it for sizing! 

Here is a link to a version by Woodside.
http://www.woodline.com/instructions/Speed-Chart.jpeg
THIS one is getting put on the router table! I love visual aids!!!

What is the little chart on the LH side?
Is the plywood there to prevent sawdust? I like that idea.
~M


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## hawkeye10 (Jul 28, 2015)

Moz said:


> Oh AWESOME chart!
> It is made to place the bit next to it for sizing!
> 
> Here is a link to a version by Woodside.
> ...


It's another speed chart. Don't ask me why cause I don't know. :laugh2:


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## Moz (Nov 13, 2015)

How did you attach the plywood sides around the table base?
I'mma steal that idea. Anything to help keep the dust off stuff is welcome

~M


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