Planing with a router - which bit do you use?

[Prashun Patel]

I have to thickness a couple 100"+ walnut slabs for a dining table. I'm planning to do this with a router on rails.

I was planning to go at this with a 1" bottom cleaning bit, but Amazon's Big Brother search engine found me out and suggested I get this:

http://www.amazon.com/Magnate-Surface-Planing-Bottom-Cleaning/dp/B0093C1ZNC/ref=sr_1_fkmr3_2?ie=UTF8&qid=1414329965&sr=8-2-fkmr3&keywords=router+bottom+flattening+bit

Has anyone used a bit like this on a 2hp or 3hp router?


Is it advisable to use a smaller bit so I can take slightly deeper cuts? I have no aversion to cleaning up with a handplane.

Other suggestions of bits to use welcomed.

[Mark Wooden]

The only experience I've had with having to surface with a router was with a large convex surface. We found that a large tray/bowl routing bit gave the smoothest finish because of the radius on the corners of the bit.
http://www.eagleamerica.com/product/vp13-2502/pc_-_groove_forming

[James Zhu]

https://www.youtube.com/watch?v=qtkBZHLJyD0

Marc Spagnuolo used Amana 45453 1 3/4" diameter straight bit to flatten the workbench top in the video, check it at 4:03.

[Cary Falk]

1/4"shank on a 1 1/2" bit does not sound like a good idea.

[Mark Wooden]

1/4"shank on a 1 1/2" bit does not sound like a good idea.

It's not, too much chatter/vibration

[Rich Engelhardt]

Over on Router Forums those Magnate bits get pretty good reviews.
The other cheapie that fares well is the Yonico (http://www.amazon.com/dp/B00KZM20GU/ref=asc_df_B00KZM20GU3373257?tag=thefind0126298-20&creative=395261&creativeASIN=B00KZM20GU&linkCode=asn)
http://www.amazon.com/dp/B00KZM20GU/ref=asc_df_B00KZM20GU3373257?tag=thefind0126298-20&creative=395261&creativeASIN=B00KZM20GU&linkCode=asn

Sorry - I haven't used either, but, I was looking at Router Forums for suggestions.

Naturally - as expected - Whiteside &/or Amana get top marks over there for the best.

[Bill McNiel]

I do a lot of router sled planing of large hardwood slabs, 1 to 2 per month on average. After trying numerous bits I settled on the Magnate 2706 Bottom Cleaning Bit ( 2" cutting diameter, 3/4" cutting length with a 1/2" shank) in a PC 890 (2 1/2 HP) running at 16,000 RPM. This bit really does a solid job but be aware that upon completion of the planing process there will still be a need to sand out the tiny ridges, more like registry lines, that one gets with any bit in this process. Magnate seems like a solid company; wide selection, reasonable prices, quick shipping, good people and the bits outlast any of the others I have tried.

Someone else here has undoubtably had a good experience with a different set-up and I welcome their input as well.
.

[scott vroom]

Prashun, what type of planer do you have? I've planed a number of 10'-13' boards on my 15" using infeed-outfeed roller stands. Are your boards too wide for your planer?

[Bruce Page]

I bought one of these to surface the spoilboard on my cnc router. It works great.
Freud 12-194 (http://www.amazon.com/gp/product/B00004T7CZ/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1)
What ever you decide on, I would not go with anything that has a 1/4" shank.

[John TenEyck]

I've done a couple of large slabs with a Grizzly 1/2" shank bowl bottoming bit in my 3 HP router and it did a great job. Straight to the ROS afterwards.

John

[Prashun Patel]

Thanks Guys. I did not realize that shank was 1/4". I definitely would use a 1/2" shank bit.

Scott, the slabs are each 22-24" wide. I am SO tempted to rip them down the center and then run them through the planer. But I think I'll have more issues re-gluing them perfectly.

John, do you have a picture of the sled you used?

The other issue I have is that the slabs are over 100" long. So making straight rails for the router is an issue; I'll have to bricklay a couple 8' sections and then joint the rails, I guess.

[Ray Newman]

Considering the length of the material-- 8 feet + and almost 2 feet wide -- that you are attempting to thickness, I would obtain some bids from cabinet shops/lumber yard as to how much they would charge to run it through a large surface planer and/or drum sander.

[Dave Kirby]

1/4"shank on a 1 1/2" bit does not sound like a good idea.

^^^THIS x10!!!^^^

[Kent A Bathurst]

........I am SO tempted to rip them down the center and then run them through the planer......

To quote Conrad in The Heart of Darkness: "The horror!!! The horror!!!" :eek: :eek: :eek:

Take one more step closer to that line, and we will be obligated, by blood oath, to convene The Secret Society off-forum to decide your punishment. You will be notified of the penalty assessed.

Router sled or machining service.

[Alan Lightstone]

I usually go for the biggest bottom cleaning bit I can find.

[Prashun Patel]

Alan, do you have a picture of the jig you use?

[Jeff Lucht]

Prashun - here are pictures of the jig I built. It is a slightly modified version of the Nick Offerman flattening jig that was featured in the FineWoodworking article. I oversized it a bit to accommodate a 44" wide slab I was making into a dining room table. I clamp everything to my assembly table and level it. I can then store all the individual pieces when I am not using them. I will re-run them through my J/P if they warp at all. Ideally I would love to be able to do slab flattening in some sort of outdoor setup because of the mess it makes.
299145299146

[Prashun Patel]

Thanks, Jeff. That's very nice. I'll build the Offerman jig, I guess.

Here are the slabs. I'm not sure if it's more work to build a huge rig/jig for this or to just flatten it by hand...

[Jamie Buxton]

Here's a thread about flattening big slabs with a router bridge ---
http://www.sawmillcreek.org/showthread.php?97018-Face-jointing-a-big-plank-with-a-router-bridge&highlight=slab

[Jim Becker]

For this kind of thing, I'd also go to the trouble to build the jig and use a router, especially when multiple slabs will be involved...like for a future dining table I have planned that uses a couple of large cherry slabs. I'd probably opt for a 1/2" shank bit in the 1.5-2" diameter range and if I could find one with a slightly rounded edge, that would be my choice...more forgiving on overlaps. The nice thing about using the jig is you can shim and work things out to get an even thickness, too.

[James Zhu]

If multiple slabs will be involved, probably worth buying the Woodhaven planing sled and supply your own rails.

https://www.youtube.com/watch?v=8aWze4UM32U&list=PL8C642BB5BB948ADE

[Prashun Patel]

Thanks for posting that thread, Jamie. That's exactly what I'm trying to do - bookmatched halves. The issue is that my bench space isn't large enough to accommodate this, so I have to do it on horses. The string trick is just the ticket I need to get my my rails level.

I am also very interested in how you draw bolted the two halves. I think my neighbor would love the ability to take the table apart if/when they move.

Can you post some pics of that? What bolts did you use?

[Jamie Buxton]

Thanks for posting that thread, Jamie. That's exactly what I'm trying to do - bookmatched halves. The issue is that my bench space isn't large enough to accommodate this, so I have to do it on horses. The string trick is just the ticket I need to get my my rails level.

I am also very interested in how you draw bolted the two halves. I think my neighbor would love the ability to take the table apart if/when they move.

Can you post some pics of that? What bolts did you use?

Unfortunately, no pics. The draw bolts are pieces of 3/8" threaded rod. There are 1/2"-diameter holes in the edges of the slab, leading to routered-out nut pockets. The threaded rod goes into the 1/2" hole before the slabs slide together.

[Myk Rian]

I used a 1" bit to do this slab. Never heard of Magnate brand.

299213

[Kent A Bathurst]

I am also very interested in how you draw bolted the two halves. I think my neighbor would love the ability to take the table apart if/when they move.

Can you post some pics of that? What bolts did you use?

Prashun - SOP hardware for long countertops. Google countertop draw bolts, and get a jillion hits.

one example, at random:

http://im-7.eefa.co/ha-262.96.946-s7.jpg




http://www.kitchensource.com/counter-tops/images/ha-262.96.946-spec.jpg

[Keith Hankins]

Most others had great ideas, I'd add if you going to sling a bit over 1", I'd make sure that router has soft start. That's a lot of torque to wind up all at once. I've got a sled I use for making 8 sided pencil post beds that uses a 7518 and a 2.5" bit. I make sure it's under control and without the soft start, I'd not want to try it. Any other use she'd be in a table. Good luck and stay safe.

[Bill McNiel]

I use the 100 mm Zipbolt Countertop Connectors from Lee Valley ($2.10 @)

[Prashun Patel]

Thanks, Kent. I will use these. I saw these @ LV. I was concerned that the little allen hole would strip out. These slabs are > 100 lbs each.

I might just do as Jamie did and use draw bolts with an open-ended wrench.

Keith, thanks for the idea about the softstart. I have a Hitachi 2hp that has a variable speed, so I will probably use that.

I'll be using this bit. I gotta say though, this slab is surfacing so nicely with planes - any direction, no tearout - and it's already close to flat, I'm tempted to just do it by hand...

WHAT AM I SAYING?!!!!!

[Prashun Patel]

I decided to use some QS white oak; I may have to do this in the future, so I wanted something reasonably stable. I made 'L's on the bottom for clamping, per Jamie's design.

Making rails this long was a challenge for me. I ripped them as long as I could with a track saw, which produces a better jointed surface on long stock than my table saw (read: me at my table saw). Then I screwed/glued extensions.

They were still not flat or square enough, so I screwed the two rails together then ran the rig through my planer. This produced two identical 108" extended rails that were perfectly square to the faces.

I'll pocket screw identical cross pieces between the rails to support the slab and to shim it up closer to the top of the rails. I overhung the clamping "L's" by 1/4" on the inner face to allow registration for those cross pieces, and to help distribute the load.

I can't help but feel this is a little over-engineered. This slab loves being hand planed, so I'll likely correct any sins at the end with that.

Question: How do you guys rip thick things with portable tools? My track saw doesn't have the depth of cut. I am considering planing the thickness down to accomodate the max cut 1 5/8 of the track saw.

How do you joint thick edges?

I was considering this if the track ripped joint isn't good enough:
Glue the two halves together. Route a 1/4" channel through the seam. Rip the pieces apart. Flush trim the edges on each half with a top-guided bit and then from the other side if necessary with a bottom guided bit. Will doing it in multiple passes compromise the truth of the joint? I am concerned that using a 2" long flush trimming bit may flex if I do it in a single pass. Am I wrong?

Stupid? Too much effort?

[Jamie Buxton]

.. How do you joint thick edges?...

So you have a track saw which can cut a straight line the length of the slab. It just doesn't have the depth of cut. One approach is to make two passes with the saw -- one from the top of the slab, and the other from the bottom of the slab. I wouldn't worry about precisely aligning the bottom cut with the top cut. I'd offset the bottom cut slightly to the waste side. Then I'd stand the slab on edge and get out those handplanes to trim the bottom cut to flush with the top cut.

If it turns out that your tracksaw doesn't cut perfectly straight, you may see a gap in the middle or at the ends when you butt the two planks together. Again, a handplane can improve the fit.

For ease of transport, I'd build this big table top as two planks which assemble on-site. That is, there is going to be a seam running the length of the top. I might even put on a microbevel like manufacturers of prefinished flooring. The seam won't be visually obnoxious; you're already seeing these two big planks. And the seam/crack/microbevel means that the edge-jointing on the slabs doesn't have to be 100.000% perfect.

[Bill McNiel]

Prashun,
My process to join two thick slabs using a tracksaw and router;
-Prelim cut the two edges that will be jointed (TS for max depth and then router with a pattern bit for the balance of depth of cut).
-Butt the two slabs together (level and true as possible)
-Recut the joint with the TS cutting both slabs simultainously (this creates a perfectly matched joint as viewed from the top/exposed surface)
-Router with pattern bit for the balance of depth of cut
-Use dominos for joint registry
-Drill and rout for coutertop connectors
-Apply finish
-For final install pull the slabs together (use bar clamps with padding to protect live edge as required) and then install Coutertop Connectors (they are really only used to keep the slabs together
-Mount on base

Hope this helps -

[Prashun Patel]

Thanks for all the help so far.

I'm going to start router-planing the bottom side first.

I had a chance to add cross braces and to level my rails today. That string trick is wonderful. I drilled 4 screws at opposite corners and wound cotton string clockwise. Pulled it taught and then drove the screws home. The screws tighten the string even further. It shows you immediately where the twist is. I shimmed the corners of the bed under the low string until the two strings kissed and it was level. The other trick is to shim the higher string up the width of the line such that when the lower comes up to kiss it, the two rails are actually coplanar - and not off by that width. It's hard to describe, but easy to get yr head around. The Wood Whisperer shows this technique really well. This whole thing takes a little time, but is straight forward and doesn't involve any guesswork.

Happy to report that after correcting the rails, the slab doesn't rock, so the top is already fairly flat! I got lucky.

Now time to build the router sled. The old one in the picture isn't good; the slot's too narrow for my new bit, and it rocks (in a bad way); I made the mistake connecting the bottom TO the sides instead of the sides to the bottom. This resulted in protruding pocket screws in the base, and doesn't allow the straight sides to pull out any bow in the base. What was I thinking ?!

[Art Mann]

I frequently use a 2" diameter, 1/2" shank diameter Magnate bit similar to the one in the link to resurface the spoil board on my CNC router. My experience is that it does a very smooth job on MDF rather quickly. I expect it would do well with hardwood using a frame supported router operated by hand.

[Prashun Patel]

Took about 45 minutes to get low enough for an even pass across the entire slab.
My rails are a little short, but the ends cleaned up easily with a hand plane.

I'm a little nervous about getting the two slabs exactly equal thickness.

I'm using a fixed router base for this. I like the idea of locking down the bit depth and not relying on the plunge mechanism to repeat exactly the same. (I know that sounds dumb). The other reason for using a fixed base is the lighter weight, and lower grip. This makes it more ergonomic to slide the router back and forth with one hand while gripping the sled with the other.

Of course, midway through my second surface, I got too comfortable. Big spark. Motor stopped. Thought I burned out the motor or hit some metal. No. I routed through the cord ( I know that sounds dumb.) Please say this has happened to you :(

That black streak on the bottom is from a nail I found buried inside. This will be the bottom. I'll book match on the left side, since it's more straight. The issue is that I want a little Georgia O'Keefesque gap in the center, but the sapwood and beveled edges create some issues for that; getting beyond the bevel may require removing all of the curve. Leaving some of the curve may leave too-skinny a sap band that could look unfinished...

[Jim Becker]

Of course, midway through my second surface, I got too comfortable. Big spark. Motor stopped. Thought I burned out the motor or hit some metal. No. I routed through the cord .

In the immortal words of Homer Simpson...

"D'oh!!!!!!!!!!!!!"

[Pat Barry]

Of course, midway through my second surface, I got too comfortable. Big spark. Motor stopped. Thought I burned out the motor or hit some metal. No. I routed through the cord ( I know that sounds dumb.) Please say this has happened to you :(..
Thats a big reason why these things are double insulated. Good safety factor.

[Prashun Patel]

Ok, I've completed all four sides. I don't know if I will do this again (unless the slab is much smaller and can fit on a stable reference like my bench).

Here's what I liked: It was very good at removing most of the twist and getting to pretty flat.

Here's what I did not like:
1) Something was shifty in my set up. I can't tell if the bed was wracking under the weight of the slab even after squaring it. I tested for coplanarity halfway through and it fell out a tad. The slab did not rock either before or after the fix though. ???
2) It's hard to keep the bit depth perfect and to avoid tearout. This method is very fatiguing and it's too tempting to overdo the depth of cut. I got some cross-grain tearout in places that needs to be fixed with my plane anyway.

[Prashun Patel]

I ended up completing the flattening by hand (bless the Veritas BU Jointer, it's a joy to use).

I have an EZ Smart guide but it only goes to 100". These are 108". Also the base makes the depth of cut just too shallow.

I made my own straight guide and removed the EZ base, but the saw is hard to dial into 90. I think I'm going to suck it up, rip it as well as I can, and then edge joint it by hand (the Veritas edge jointing guide is really nice to use too!)

Figuring out how much of the middle to rip is tricky. Looking for some symetry of the sap wood, but have to work around the alternating bevels. Also leaving some of that center sap band will result in a very wide 45" table. I may rip it all off. The grain matches fairly well along the rest of the length. Design critique welcome!

[Kent A Bathurst]

Personal choice. Me - I don't like the sapwood contrast. Outer edges mutch more aesthetically pleasing to me than sapwood down the center - looks like a racing stripe on a SuperBee. Your call.

On ripping for center match:
1. pick a common grain ref point both ends, both pieces - somewhere you know the grain matches.
2. Measuring from those ref points, rip inside waste, but leave 1/4" + extra waste.
3. Now you can butt them together, and start running the blade down the common seam, as suggested way earlier. Will take 2+ passes.
4. Keep it up until you have a perfect match.
5. Slip/slide the 2 pieces to get the book matching correct.
6. Glue it up.
7. Trim the ends.

[Jim Becker]

Honestly, I'd love to assemble the table exactly how your slabs are pictured in post #38...with the groove and some creative splines to reinforce and add some splash. Given the length, the 45" wide wouldn't scare me one bit! I would like that proportion. (And have a room it would fit in very nicely) That said, it would also likely look very nice if you had to do the center rip, but you could still leave a 1/2"-3/4" wide open groove down the middle to make for an interesting table that hints at a bookmatch.

[Prashun Patel]

Thanks for the opinions, Guys. I'm on Kent's side of the fence on this I think. I like trying to find that line between organic and refined. A 2 slab table (while SO appealing for the ease of construction) just feels 'rustic' to me. Kent, I take your point about getting rid of the center sap line altogether. While it may take more time, I might just nibble away at the edge until it feels proportional and right.

Off the circular saw, the cut is a little ragged for my taste - even with a guide providing zero clearance on the good side. Also, like I said, the blade doesn't make it through all the way. I think I have to tediously: flip, cut good-side-down, complete with a handsaw, flip, flush trim with a router.

Given that I'm planning to make several cuts to sneak up on the final width, if anyone has a more efficient method, I'm all ears. Boy, if I could JUST put an 8 1/4" blade on my saw.

[Prashun Patel]

Here's the first nibble...
I think if I try to get rid of all that center sap, it'll remove maybe too much of the straight heartwood grain at the bottom and top.

Kent? Rip more?

[Prashun Patel]

More trimming.
I was able to rip the slabs and complete the cut with a pull saw.

I used this Veritas jointer plane to smooth it. Man, what a joy! This wood and this plane just made it so easy for someone like me. The edge guide is fantastic. I couldn't figure out how to stand the boards on edge since my bench space is too small, but I was able to shoot it pretty square. I'll find out on Monday if the glue line is straight enough...

There's still a tiny bit of sapwood in the middle :( Let's see how it looks when the boards are side by side.

["Felix Marti"]

Thanks Guys. I did not realize that shank was 1/4". I definitely would use a 1/2" shank bit.

Scott, the slabs are each 22-24" wide. I am SO tempted to rip them down the center and then run them through the planer. But I think I'll have more issues re-gluing them perfectly.

John, do you have a picture of the sled you used?

The other issue I have is that the slabs are over 100" long. So making straight rails for the router is an issue; I'll have to bricklay a couple 8' sections and then joint the rails, I guess.
-----------------------------
Hello Prashun.
I believe the Wood Whisperer did a video on the exact task you have before you (http://www.thewoodwhisperer).
The length of rails you need to construct is no challenge. If there were a means of talking I could talk/show you the process.
Felix

[Mike Heidrick]

I use a yellow import 1.75" dia 1/2" shank one from Ebay but I am only surfacing MDF on my CNC table.

[Art Mann]

I believe I am using the 2" version of that exact same bit to periodically resurface the spoil board on my CNC router. It works well for me.