Flatten and end grain board

[wtnhighlander]

Making a small cutting board today, I needed a way to flatten it after final glue up. I have no drum sander, and this piece is too small for the planer, even if that wasn't a terrible idea. So, I came up with this inverted sort of router sled. I just cut some sacrificial strips just wide enough to glue on opposing sides of the board, so it could float between them. Then I ran it along the fence of my TS router table insert, over a flat end bit. Rotate 180*, make another pass. Move the fence about 1 bit width, rinse and repeat. Worked like a charm, much simpler than a sled for the router to ride in.

[Coop]

Now that is cool!

[Immortan D]

Great idea!

 

[TerryMcK]

A great way to flatten. 

[treeslayer]

great idea, thats going to be one sweet cutting board

[weithman5]

very clever, any concern about getting the sled boards off after gluing?

i have tested silicon caulk to hold things temporarily, then slowly can pry apart, not tried on anything formally

[wtnhighlander]

very clever, any concern about getting the sled boards off after gluing?

i have tested silicon caulk to hold things temporarily, then slowly can pry apart, not tried on anything formally

I used hot glue, and sawed them off to square up the board, anyway. Doing it over, I would cut a bit farther from the glue line. Hot melt glue makes a gummy mess on the saw blade.

[Brendon_t]

Ross, I use the same theory to get the first flat side on the drum sander. I glue in a taller piece on each side,  plane one until it sits nicely on the table saw top. That's my first registration surface.  Once the side facing up is flat, rip the pieces off, flip it  and run the other side. 

[ponderingturtle]

I would consider using some serious glue and cutting the boards off after.  I would just be uncomfortable pressing down on any joint intended to be temporary firmly enough to make sure it got an even cut.

[AceHoleInOne]

Beautiful board, but this comes to mind. The pieces that have pith (center of tree) Is that a good idea? That area isn't very stable and chunks of the pith may dislodge over time causing a hole for food and whatever to get down into?

Or am I just being to anal?

-Ace- 

[wtnhighlander]

Ace, I hope its just you! Actually, those are what I would call pin knots, where the board was cut near a branch. Hopefully those will remain more stable rhan the actual pith would.

[wtnhighlander]

I would consider using some serious glue and cutting the boards off after.  I would just be uncomfortable pressing down on any joint intended to be temporary firmly enough to make sure it got an even cut.

I think you misunderstand how I used this rig. There is no pressure on the cutting board, only on the runners I glued on. So there is very little stress on the joint. Hot glue hold well and works fast, just don't try to remove the runners by sawing right along the glue line, because hot glue gums up the blade.

[AceHoleInOne]

Ace, I hope its just you! Actually, those are what I would call pin knots, where the board was cut near a branch. Hopefully those will remain more stable rhan the actual pith would.

I hear ya, but branch wood contains pith too. Since the cutting board is end-grain. And seeing the rings, one would have to think pith. Typically small pin knots and or knots in general show on the face side or long grain of boards.

Maybe I got it wrong?

-Ace-

[ponderingturtle]

I think you misunderstand how I used this rig. There is no pressure on the cutting board, only on the runners I glued on. So there is very little stress on the joint. Hot glue hold well and works fast, just don't try to remove the runners by sawing right along the glue line, because hot glue gums up the blade.

Then what is keeping it solidly referenced to uniform cut?

[wtnhighlander]

I hear ya, but branch wood contains pith too. Since the cutting board is end-grain. And seeing the rings, one would have to think pith. Typically small pin knots and or knots in general show on the face side or long grain of boards.

Maybe I got it wrong?

-Ace-

Time will tell. If what I see is the same as what you see, the knot or pith doesn't go all the way through, so maybe it will remain stable. I have some time before it goes to the recipient, so I'll watch it closely.

[wtnhighlander]

Then what is keeping it solidly referenced to uniform cut?

The glued on side rails are slightly wider than the cutting board blank. The rail edges rest on the table, letting the blank "float" about 1/8" above the table. I pass the blank over the router bit, guided by the fence, right along the glue line so the bit barely touches the rail. Rotate the piece 180* and repeat. Move the fence by one bit width and do it again, repeating until the passes meet it the middle. Flip it over and do the opposite side. The rails being equal width, and glued to the blank while reference from the flat table surface, allows this rig to produce flat and parallel sides. All the downward pressure is on the rails, rather than the blank.

[phinds]

This is a great idea. It's the kind of thing I wish I had thought of.

[Coop]

Ross, how will you/did you, remove the rails from the board, as the rails are now higher than the board?

Edited October 21, 2015 by K Cooper

[wtnhighlander]

Ross, how will you/did you, remove the rails from the board, as the rails are now higher than the board?

The rails were soft pine. A few passes with a jack plane brought them level with the blank, the I cut them off with the TS. That's where cutting right at the glue line was a mistake, as the hot glue gummed up the blade. Took a lot of scrubbing to get it off. I suppose one could break the hot glue joint, but I didn't try. An alternative is to use a scrap of plywood under the blank to hold it level with the rails not touching the table, and cut the rails off at the band saw.

[ponderingturtle]

The glued on side rails are slightly wider than the cutting board blank. The rail edges rest on the table, letting the blank "float" about 1/8" above the table. I pass the blank over the router bit, guided by the fence, right along the glue line so the bit barely touches the rail. Rotate the piece 180* and repeat. Move the fence by one bit width and do it again, repeating until the passes meet it the middle. Flip it over and do the opposite side. The rails being equal width, and glued to the blank while reference from the flat table surface, allows this rig to produce flat and parallel sides. All the downward pressure is on the rails, rather than the blank.

I understand that it is an upside down router sled with the board on the sled part.  But if there were upward pressure from the bit it might lift up against gravity and providing pressure opposite the cutter would be more stress on the joints.

[wtnhighlander]

I understand that it is an upside down router sled with the board on the sled part.  But if there were upward pressure from the bit it might lift up against gravity and providing pressure opposite the cutter would be more stress on the joints.

Agreed, but the cutting action starts from off the board, and is cutting from the side, so no vertical force is involved. I'm not saying hot glue is the best option, by any means. But it is quick.

[AceHoleInOne]

Ya know, I use a lot of times is double sided tape. I think it would work nicely in this situation. Most times you need to work a putty knife in to release the tape.

-Ace- 

[ponderingturtle]

Agreed, but the cutting action starts from off the board, and is cutting from the side, so no vertical force is involved. I'm not saying hot glue is the best option, by any means. But it is quick.

So if there is no sideways forces at a tablesaw why would anyone ever use something like a feather board on one?  I think I would feel more comfortable sacrificing a 1/4" and using normal wood glue.  Or a more traditional form of router sled.

[wtnhighlander]

So if there is no sideways forces at a tablesaw why would anyone ever use something like a feather board on one?  I think I would feel more comfortable sacrificing a 1/4" and using normal wood glue.  Or a more traditional form of router sled.

OK.

But I said no VERTICAL force, not sideways.

[Vyrolan]

OK.

But I said no VERTICAL force, not sideways.

He meant that in a tablesaw, all the force is in theory vertical...the blade is spinning vertically, yet we use featherboards to hold the stock horizontally...   Rotate that 90 degrees for your jig and you have horizontal cutting but no vertical pressure holding the stock being cut.

However, I don't think that matters...I think our pressure down and into the fence on table saws, router tables, etc is more about maintaining straightness and alignment of the cutter along our desired path...not to counteract a "sideways" force from the cutter.

I think with light cuts Ross's idea would work fine...sure you may get a tiny bit of chatter in the middle where cutter's force causes a slight bit of upward pressure that you're not counteracting in anyway, but it should be very minimal.   I also doubt he took them straight from this jig to the finishing...some quick passes with the ROS would take care of the final smoothing.    Using his jig would still cut out a ton of "make you quit woodworking" endgrain sanding from the process.

 

Also ponderingturtle you seem to be worried about the stress on the glue joints against the runner if you pressed down into the but, but screw that, I'd be a helluva lot more concerned about the piece getting a nasty catch along a glue line and cracking apart...and here's your hand right over the bit pressing down...that sounds unsafe as heck....even with a push paddle or grrripper or anything.    You'd also have to control how much pressure your apply very delicately...if you push too hard trying to counteract the bit of upward force from the cutter's shear then you could bow the board down and it wouldn't be as flat.   I think Ross's no-pressure-on-top approach and very light cuts so the board's natural strength prevents any upward bowing is a safer and better approach.