flattening heavy glue ups

[John Piwaron]

I've glued together the two halves of what will be a split top roubo workbench. Now flattening is required. They're heavy. Too heavy for me, working alone, to easily take anywhere to be thickness sanded. They're hard maple, planing isn't a great option because of the risk of tearout.

What I'm doing is using my belt sander for the task. It certainly doesn't seem like an obvious choice. It came to me to do it that way when I recalled having built the bench that is the cover story in issue #50 of Woodsmith magazine long ago. In that issue. The central slab is flattened in that manner.

Remarks? Pitfalls to be aware of?

Maybe I ought to make the effort to get them to a proper thickness sander to ensure uniformity between the two halves.

[scott vroom]

Maybe I ought to make the effort to get them to a proper thickness sander to ensure uniformity between the two halves.

That would be my choice. Do you have access to a pickup truck and a helper? There are folks here with the skill to flatten using hand planes, I'm not among that group.

[Kent A Bathurst]

YOu want the top side to be flat. I personally would not sweat an uneven bottom side.Shims to mate to base/frame.

[Mark Carlson]

How about using a router sled? I watched a video on the thewoodwhisperer.com where he did just that. I did the same thing on a much smaller scale to flatten some cutting boards.

~mark

[John Piwaron]

No pickup, I have a small utility trailer.

The router sled idea is good.

Calling my friends, the geriatric gang, makes a router sled the more attractive thought.

[Gene Davis]

Mark at Wood Whisperer walks you right through it with an excellent video, and he is using a router and sled. First step, place and fix the rails so they are perfectly parallel, and the panel to be flattened has its highest point or corner just barely below the surface of the temporary rails.

And lo, when he is done, he proclaims the routed surface good to go, needing no further smoothing.

Video up on YouTube. Search and you will find.

[Kent A Bathurst]

The router sled always looked pretty cool to me. But - a lot of work to build, and a LOT of work to use for a large surface. I have concentrated on flat glue-ups instead.

[Joe Kieve]

To save you some time, here's a link to the video that Mark and Gene mentioned http://www.youtube.com/watch?v=qtkBZHLJyD0

[Jim Matthews]

They're hard maple, planing isn't a great option because of the risk of tearout.

Bwah?
Softer stuff gives me more trouble than genuinely hard woods.

Roubo his own self did not have wide belt sanders, and managed.

Daunting, to be sure but so is traction after spraining your back wrestling with the slabs.

Router sleds will get you close, but you're still in for some finish planing.

Do you have a decent scrub plane for the job?

[David Robertson1]

I made a counter height table for my wife out of hard maple and decided to use my 4" wide belt sander to flatten/thickness plane instead of my hand planes. I had so much fine saw dust I saved it in mason jars (several).

I believe it would be easier in the long run to use virtually any other method like listed above. One thing that is easy to screw up on a belt sander is to round over the ends. Anything that machine touches, it eats. Then your left with 300x more work in removing the marks that the belt left.

Even though the table came out nice, I regret putting my belt sander anywhere near that table.

Just my little contribution, good luck.

-David

[Harold Burrell]

I just finished my roubo a few months ago. My initial flattening was with a router sled (please don't tell the guys on the Neader side :eek:). I finished it off later with hand planes. As Kent said, you don't have to worry about the underside too much.

[Ed Labadie]

Router sled here....

Ed

[John Piwaron]

I just finished my roubo a few months ago. My initial flattening was with a router sled (please don't tell the guys on the Neader side :eek:). I finished it off later with hand planes. As Kent said, you don't have to worry about the underside too much.

The fact that you use power tools but fly the hand tool flag is a secret that's safe with me.

[John Piwaron]

I don't have too many planes. A block, a small Lee Valley shoulder plane, a Record 05 and 07. Not a big choice.

I've asked my SIL to help carry it to the trailer to take it to the place with the thickness sander. Then back into the shop. I'll have them sand both sides while they're at it.

[Myk Rian]

No pickup, I have a small utility trailer.

The router sled idea is good.

Calling my friends, the geriatric gang, makes a router sled the more attractive thought.
My router sled for the table saw. It rides on the fence rails.

297983297984

[Jim Matthews]

The fact that you use power tools but fly the hand tool flag is a secret that's safe with me.

Traitors, turncoats and scaliwags - you scabarous dogs.
Of course, the Neanderthal code is more a set of guidelines...

[John Piwaron]

My router sled for the table saw. It rides on the fence rails.

297983297984

Ryan, could you post some more pix to more clearly show how yours works? It looks interesting.

[Erik Christensen]

I had to flatten my 3 1/2" thick hard maple work bench top a year ago. I was not confident of my hand planing skills so i only did the bottom with hand planes - the top I did with a router sled. Overall the sled might have been a bit flatter over the 8' length but the hand tools were faster start-to-finish. the only thing I would use a sled on for sure would be some type of live edge slab that i am sure I would hack up with hand tools.

[John Piwaron]

Well, it's done. Flat both sides of both halves. Son in law and I took them to Kettle Moraine hardwood where I them put through their big sander. The eyes of the store's manager bugged out a little when I told him how big the pieces were, otherwise it was just another day at the office. $5 a minute. It cost me $40. And saved me a lot of time. fwiw, it was the stores employees that did the work. They don't let me back there with the tools.

[Garth Almgren]

An excellent solution, sounds like it was well worth the $40 investment.