How to mount 5/8" shank in Router

[Doug Hepler]

I was considering the use of a 5/8" upcut spiral bit in my handheld router (PC 690). All such bits I could find appear to have 5/8" shanks. Naturally, these would not fit in my 1/2" collet. I have been unable to find a workaround, leading me to suppose that such large bits are meant for milling machines, etc, not routers.

Do you use a 5/8" spiral bit in your handheld router, and if so, how do you mount it?
If this is generally a bad idea, why is that?

Doug

[J.R. Rutter]

They are milling bits. You should be able to find 1/2" bits that are otherwise the same. I have a few that I got years ago.

[Gerry Grzadzinski]

If you need a 5/8" router bit, get a carbide tipped 2 flute.
I use 5/8" spirals on our CNC router, with a 10HP spindle. But there's nothing similar available for handheld routers. You can probably get one made for about $300+.

[pat warner]

Boring data.
Most solid carbide router bits have the same cutting diameter as their shanks.
Grinding this stuff down is too expensive.
The 5/8 shank could be turned down to .499 but that too would be expensive.
Industrial routers use bigger shanks, 5/8 - 3/4", typical.
I also like 5/8" CD cutters but use brazed on carbide (on steel).
Straight not spiral; the spirals carry too many spontaneous surprises.

[Ray Newman]

Interstate # 320-2848; Heretl # 337-5069.

See p 122 of ENCO master catalogue:

5/8" end mill dia, 1/2" shank, 1 5/8" long cut, 2 flutes, TiN coated, approx. US$#15.00 Interstate, $23.00 Hertel + s/h

http://www.use-enco.com/CGI/INPDFF?PMPAGE=1109

[Doug Hepler]

Ray,

Thank you a lot. Your response opens up a new area for me. An end mill of the size I need costs about 1/5 or less of an Onsrud router bit of the same diameter. That's great.

I have heard the term end mill before, and I have now read descriptions and looked at pictures. They look a lot like a router bit. Beyond that, I am not familiar with them. I will be reading about them. I understand that some end mills will not cut straight down. My specific questions are (a) is there a trade designation for an end mill that will cut straight down or plunge into wood? (b) am I correct to assume that an end mill with a 1/2" shank will go into a normal 1/2" router collet? and (c) are these meant to operate at typical router RPM?

By the way, the exact ENCO model number you gave me no longer is valid. Just for your information. Now that I know what to "ask" for I will have no trouble finding what I want. They have a 4-flute bit that looks pretty cool.

Thanks again

Doug

[Myk Rian]

I was considering the use of a 5/8" upcut spiral bit in my handheld router (PC 690). All such bits I could find appear to have 5/8" shanks. Naturally, these would not fit in my 1/2" collet. I have been unable to find a workaround, leading me to suppose that such large bits are meant for milling machines, etc, not routers.

Do you use a 5/8" spiral bit in your handheld router, and if so, how do you mount it?
If this is generally a bad idea, why is that?

Doug
Ain't going to happen. Why? They don't make a 5/8" collet.

[Bill Orbine]

Amana has 'em. Here's a link to one of the many: http://www.amanatool.com/46263-cnc-solid-carbide-spiral-plunge-for-solid-wood-1-2-dia-x-1-5-8-x-1-2-inch-shank-up-cut.html

The downside........expect to pay some $$$$ as most of these spiral ups or downs are solid carbide.

[Greg Hines, MD]

I would question why you need that size? Its generally easier to use a smaller bit and make two passes to do the work. For example, if you are plowing out a 5/8" mortise, make two passes with a 1/2" bit and you can make it exactly 5/8" wide.

Doc

[michael langman]

An end mill that you can plunge with is called a center cutting end mill. End mills for aluminum have a different helix when using the end mill for cutting aluminum and softer non ferrous metals.. Tin coating is well worth the extra cost .

[Brian Gumpper]

Those are High Speed Steel, that's why such the price difference.

[Doug Hepler]

Greg, I am using a bracket jig with a guide collar and cutting tenons by the distance between the cutter and the guide collar. Given available guide collar diameters, a 5/8" dia cutter works out well. I know I can use a straight bit, but a spiral bit cuts so much more cleanly. I have always cut tenons with a saw, but on my current project I am experimenting with this jig. Probably I should have provided more detail in my OP but I did not want to complicate the question.

Michael, thank you for answering my question

Doug

[pat warner]

So the cutter is between the bracket jig and the work?

[Doug Hepler]

Pat

Yes. I have always advocated laying out the tenon itself instead of measuring the waste to be removed. But this method cuts the whole tenon, measured from a reference edge and produces accurate tenons regardless of minor variations in the thickness of the work piece. I know a lot of people cut tenons with a router this way.

Doug