New router

[Mick S]

Ultimately the depth of cut has several limiting factors, motor power being just one of them. You also have to take into consideration the material characteristics such as density, propensity to chip, propensity to burn, etc, bit diameter, bit condition (is it sharp?), rotation speed, how fast you're feeding it (to avoid burning), how well the part is secured, how well your guide system (router fence, straightedge, jig or template) is secured, quality of cut and more. 

An easy answer to your question is yes, the router has plenty of power to take a 1/2" x 3/8" cut in a single pass. And set up properly, the tool you selected will take a cut at least twice that deep all day long faster than you can move the router. A handheld router's power (torque) is directly correlated to its rotation speed. Faster rotation = more torque. Faster rotation is NOT always the best setting. The chip load directly affects the quality of cut. Chip load is the thickness of each chip being removed;  too thin and you get burning and greatly reduced tool life, too thick and you get chatter, tearout and possibly bit breakage. So chip load is a function of rotation speed, feedrate and the number of flutes. A router set to 16,000 rpm using a 2 flute bit and cutting 3/8" deep may cut beautifully at a forward rate of say, 200 inches per minute, but will fry the material (and the bit) at 20 inches per minute. Or it may snap the bit at 500 inches per minute. There's a sweet spot. Anyone who's used a router more than once has seen burn marks show up when they slow down or stop to reposition, move the cord, slow down in a corner, etc. The bit is rubbing, not cutting, so heat builds immediately. The number one cause of poor quality router results is using too high of a rotation speed for the feed speed and number of flutes. 

That's a long way around getting to the point - we're using hand held routers. The bit you chose was designed for use in an industrial CNC router moving WAY faster than you can or should be moving a hand held router. To get the same results that an industrial CNC user would get using the same bit you have to slow down the rotation speed. That means you'll have less torque than the router is ultimately capable of. That's why you get a 3 1/4 Hp router. It has the reserve power to get the job done properly at the correct rotation speed. A 1 Hp router using the same bit would need to spin faster to develop the same torque.

[curlyoak]

Thanks Tom. Makes sense. Basically slower under heavy cuts and faster with modest cuts. 

Quality service is meaningful. I have been an amana user. Due to quality service from my local suppler. I go with Amana. That what a local supplier offers. The people that run the business make me feel like family.  It just makes sense and it makes me feel good to direct business their way. I value quality relationships.

 

 

 

 

[Mick S]

18 hours ago, curlyoak said:

Makes sense. Basically slower under heavy cuts and faster with modest cuts. 

Not exactly. The chip itself is what carries heat away from the cutter. The thicker the chip, the more heat carried away. At equal rotation speeds, going slower only reduces the thickness of the chip, thereby increasing the amount of heat. If you slow down your feed rate you also have to slow your rotation speed to maintain the correct chip load (thickness of the chip).

[Mark J]

I just had no idea there was so much science in this.  Explains a lot of the router results I've experienced.

[curlyoak]

Thank you Mick! A good explanation. So for the theoretical dado example I set the speed 50% or maybe 75%. When I get to making dados I will run a few tests at different speeds. From above I want to run it as slow as is reasonable.I think as I use it I will find my way. With the good guidance from here with my previous experiences, I'm confident.

Mick are you an engineer?

[Mick S]

43 minutes ago, curlyoak said:

Thank you Mick! A good explanation. So for the theoretical dado example I set the speed 50% or maybe 75%. When I get to making dados I will run a few tests at different speeds. From above I want to run it as slow as is reasonable.I think as I use it I will find my way. With the good guidance from here with my previous experiences, I'm confident.

I think 50% would be a good starting point. If it sounds like the motor is stalling at the rate you're feeding it then increase the rpm until it sounds right.

43 minutes ago, curlyoak said:

Mick are you an engineer?

No, but I spent the majority of my career selling/consulting and training on industrial CNC routers, lasers, waterjets, plasma, etc. I was fortunate to go through the weeklong Onsrud Cutter training session a couple of times. Learned a lot!

The problem for anyone new to routing (and lots of people who have used them for years) is that the proper feeds and speeds (forward movement and rotation speed) are somewhat counterintuitive. People intuitively think faster rotation gives a smoother cut. It might for a while, but the heat buildup on the tool will, as Tom pointed out, dull the tool very quickly. The majority of time the opposite is true for wood applications. Any time I trained a new CNC router customer in a woodworking application I gave them a free ⅜" compression bit. I asked them to set their feeds & speeds to a conservative value then increase the feedrate but leave the rpm constant, until the bit broke. From there I had them set the feedrate to 10% less than they were running when the bit snapped. If the cut quality was good and the parts didn't move then that should be their correct speed for that bit.

With handheld routers we can't do that. We just can't push a router at 2000 inches per minute. So our only option is to slow the rpm to get a similar chip load. Also, the larger the bit diameter the slower the rpm, since the tip speed is so much higher on larger diameter bits. The high setting on our routers should really only be used for the smaller bits.

[curlyoak]

Mick, your knowledge on the subject is so deep on the subject. And now I know why. How lucky that you are sharing. More than I was asking for and happy to have it. I feel like I just qualified for a continuing education credits. Thank you.