2-Stage Router Cutting

[steve siegrist]

Any thoughts / experience on preserving router bit cutter life by using two stage cutting? I've got some 500LF of raised panel to cut and will be using Infinity bits. I'm considering cutting most of the profile with one bit and finishing with another (same profile) to preserve carbide cutter life and hopefully maintain quality of the final pass?

[dave toney]

I would think your idea would work fine.

[Steve Jenkins]

I think it would be fine too. If you really want to extend the life of your bits or shaper cutters cool them as they cut. I made thousands of feet of rope molding with a Legacy Mill which uses a router. I went to the MSC catalog and bought a "cold gun". this is a device that you hook up to a compressed air source and it drops the temperature of the incoming air about 70 degrees and exhausts onto the cutter. The air coming out is around 0 degrees depending on ambient temp. Useing this extended the time between between sharpenings about 10 times. It does require about 12-15cfm though.

[Jim Neeley]

Steve,

I think it's a reasonable approach. IME, the key to success will be in getting the setting of the new bit to precisely match the old. You might want to consider using bit #1 to cut an alignment template from scrap for bit #2 setup.

[Myk Rian]

Steve,

I think it's a reasonable approach. IME, the key to success will be in getting the setting of the new bit to precisely match the old. You might want to consider using bit #1 to cut an alignment template from scrap for bit #2 setup.
I believe he intends to cut MOST of the profile first, then finish it to final cut with the second.
Easy to do with scrap setup pieces.

[pat warner]

My recommendation too, made a case of it in my book and website.
I do like the cold bit a lot too, an excellent attack but you lose the chip in the process.

[Peter Quinn]

500 Lf of raised panel profile? At that point I'm searching for a shaper.

[Larry Edgerton]

I do the same thing with the shaper when the wood used callls for it, for example cherry. A light final pass can be run at a faster feed rate and not burn. When doing a stubborn wood such as Jatoba I will set up the tablesaw with a feeder and cut the waste with that to save on wear on the cutters and the shaper.

I'll second the shaper suggestion if this is not just a one time thing. Any excuse to buy a new tool will do........

Larry

[Ryan Hellmer]

With raised panel router bits you're already talking multiple passes anyways. i wouldn't worry about two bits. Most people would recomment doing at least three passes. Besides 500 LF is nothing for carbide. I didn't see what species you will be routing but unless its something exotic I would just buy the one bit and do multiple passes.

That being said, I'm in the shaper club so I wouldn't use a router anyways...

Ryan

[Floyd Mah]

I used saws (table saw and bandsaw) to remove most of the waste when I made over two dozen windows. The benefits were longer cutter life and fewer chips. The drawbacks were many milling operations on each piece of wood (more than 20 after you did each face of the wood). It was made easier by the fact that the tasks were repetitive and I could process many pieces quickly since the saw could remove large pieces of wood that would otherwise be reduced by chipping away with the router. Anyway, consider using a saw to remove some of the waste, as long as you are able to leave a reference edge for the router and the piece remaining is not unstable (odd shaped).

[Tony Zaffuto]

I think it would be fine too. If you really want to extend the life of your bits or shaper cutters cool them as they cut. I made thousands of feet of rope molding with a Legacy Mill which uses a router. I went to the MSC catalog and bought a "cold gun". this is a device that you hook up to a compressed air source and it drops the temperature of the incoming air about 70 degrees and exhausts onto the cutter. The air coming out is around 0 degrees depending on ambient temp. Useing this extended the time between between sharpenings about 10 times. It does require about 12-15cfm though.

Excellent suggestion! I use a number of these "cold guns" in my manufacturing plant for drilling/tapping operations and some light metal cutting. Should work great for wood routing.

[Chris Fournier]

The cold gun idea is neat but they are expensive, noisy and require a lot of compressor. Floyd's suggestion of using the T saw to remove the bulk of the profile is how I've done it for years and you likely already own a T saw. I take a swipe off on the table saw that leaves me with one pass on the cutter to remove most of the material and a second light pass to get the best surface finish that I can.