what is the correct bit for a router sled?

[Mitchell Garnett]

This is new territory for me and after watching videos and reading posts on various forums, it isn't clear to me whether I should use a plunge bit or just a straight bit/bottom cleaning bit. Some references in posts are just standard straight bits and others are plunge specific. Which one is right or does it matter?

thanks.

[Matt Day]

You should clarify what you mean by a router sled.

Do you mean to joint/plane wide slabs of lumber? If that’s the case, the Magnate surface planing bits are pretty well regarded I believe. No need for an upcut or anything. You’re going to be spraying chips everywhere anyway!

[Tom M King]

If you already have a large, straight cutting bit, it will work fine. I just tilt the router in to start if the router doesn't come in from the edge.

[Mike Cutler]

When I did it, I did it with a largish bowl bit I just happened to have, and it worked out.
Many of the You tube videos use a "largish" straight cutter with bottom cutter.
It's gotten to become such a "normal process" that now companies are making specific bit's for the process. Some are even insert type cutters. They look kind of like fly cutters for a milling machine.

[Mitchell Garnett]

Thanks to everybody who replied. I’ve got what I need I think.

[Jim Becker]

Just as an additional comment, obviously, using a larger diameter cutter for surfacing has some advantages for surface quality and time to do the job with about a 50% overlap. BUT...it's important to not use a cutter that's bigger than is safe to use for a hand-held router, even though a jig is being used. That's about an inch and a quarter max.

[Dylan Wyatt]

Look at the MAX speed rating for the cutter you plan to use. The last thing you want to do is get one of those big cutterheads with a non-variable speed router and attempt to cut at twice the rated speed for the bit.

[Mitchell Garnett]

Thanks Jim. You reminded me of another point - router power. I think my PC 690 will be under powered so I’ll have to get my 7218 out of the router table lift. Any thoughts?

[Brian Tymchak]

Thanks Jim. You reminded me of another point - router power. I think my PC 690 will be under powered so I’ll have to get my 7218 out of the router table lift. Any thoughts?

I used my Makita 1100 (2 1/4 hp) to plane some pieces. Not slabs, but still big enough. Just take it slower and as Jim mentions, try not to use too large a bit. I used a 1" planing bit. Worked well. anything with an edge on the bottom should work.

[Stan Calow]

I've only done this on some smaller pieces, but I like to use a 1 1/4" Freud mortising bit, just because its what I had on hand. I use it for routing tenons as well. Seems like that would be a lot of stress on the end of a straight bit's cutters.

[Jim Becker]

Mitchel, I agree that the 690, while it will work, will labor at the task. The 7518 is a better choice from a power standpoint, but un-mounting it from the table might be a pain in the you-know-what. In my case, it would be impossible because I no longer have the original base for mine. If you are planning on doing this kind of work with any frequency, it might be worth considering picking up either a mid-range 12 amp router or a heavier 15 amp router. It will spin a reasonable sized surfacing cutter and also be handy for other work that pushes the limits of the 690 or similar routers. You can never have too many of them, you know...

[Richard Verwoest]

I would also recommend the bits from Amana with the carbide inserts. If something happens(dirt, rock, nail) they are easy to rotate without changing any settings. a bit pricy at fist, but.....I would also recommend get a bit extension.

Richard

[Tom M King]

The enemy of any bit is heat, and more than a normal amount will be generated. Even that 7218 will need to be babied some, or at least, not pushed too hard. We milled the top 3/4" off of a couple of hundred feet of 200 year old Heart Pine flooring, and I kept bits in the mail, back and forth, being sharpened.

I did it in three passes. You can go faster with a lighter cut, but then you need more cuts.

Good luck.

[Martin Siebert]

I would also recommend the bits from Amana with the carbide inserts. If something happens(dirt, rock, nail) they are easy to rotate without changing any settings. a bit pricy at fist, but.....I would also recommend get a bit extension.

Richard

This!!! I have a Woodhaven router sled and I tried many different bits. They all worked and did just fine, but the one I liked best is the Amana RC-2250. It is an inch and a half cutting diameter and has the carbide indexable bits. And, as above, I had to get the bit extension. It's not that the Amana bit necessarily cuts any better or faster and it is kind of large for the average router to swing, it's that you don't need to send it anywhere when it gets dull. Which by the way is not very often. I have flattened at least 20 {probably closer to 30 in actual count} big hardwood slabs and have not had to rotate the cutters yet. I did go thru a set of brushes and so I now go slower and keep new brushes on hand. As posted previously, heat is the enemy of your bit and router both so take a thinner cut and move the router a little slower on the sled.
It appears that the Amana comes with a very good grade of carbide inserts. Not all carbide is created equal. Other fixed edge bits will probably last just as long as this one {on that one edge} as long as you get one that contains superior carbide. I also agree with Mr. King...you can take deep cuts slow or light cuts faster and get the same result. But, at the end of the day, anytime you are moving that much wood on that big of a slab somethings got to give {wear}.

[Bill McNiel]

Mitchell,
I use a Magnate Bottom Cleaning Bit #2706 at 16,000 RPM (2" Diameter, 3/4" Cutting Length, 1/2" Dia Shank) FWIW - I have flattened over 30 slabs over the years anf tried several bits with the Magnate being the best of the lot.
Regards-Bill