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jeremy romoser
03-29-2020, 2:44 PM
Some background:
I am attempting to build a desk top for my wife's home office.
I bought 5/4 s3s walnut.
I have cut the boards down to 65". Finished length will be 60"
I have not cut them to width yet but finished width will be about 5" for an overall finished glue up width of about 29-30"
Some of the boards are bowed on the face side. some on the edge side but slight enough that I should be able to remove when I cut them to final width.
While I am slightly improving with each project, I am still fairly inexperienced at wood working and even more inexperienced with hand tools.
Question is: what is the proper technique for removing the bow to have a flat face so that I can either continue hand planing to final thickness and dimensions (preferred) or run them through the small lunch box planer I have?

I currently have a LN #7 jointer, LN #62 LA Jack, and LN # 601/2 Rabbet Block plane.

Thanks to all on this fantastic site that take the time to respond.

Jeremy

Phil Mueller
03-29-2020, 3:30 PM
Hi Jeremy, a number of us would be happy to help, but first, just to make sure we’re understanding your situation, and because you mentioned both the face and the edge, are the boards bowed, cupped, crooked, twisted?

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Warren Mickley
03-29-2020, 4:03 PM
It would be helpful to know how thick your boards are right now.

In hand work, we would glue rough boards together, then flatten one side and joint an edge, then plane to thickness. This avoids flattening the boards individually, gluing up, and then having to flatten all over again. I also saves on material thickness.

In your case, given the size of the final board, I would think that you would want to aim for a full inch of thickness. Also you might need 3/16 or even more of extra thickness to play around with after the glue up. This probably does not leave much if any to plane off with your lunchbox planer.

Whatever you do, plane only the high spots. If you go over the whole board planing crosswise, or planing both diagonals like some beginners on U-Tube, you are planing low spots and diminishing the final thickness you can achieve.

jeremy romoser
03-29-2020, 4:19 PM
Hi Jeremy, a number of us would be happy to help, but first, just to make sure we’re understanding your situation, and because you mentioned both the face and the edge, are the boards bowed, cupped, crooked, twisted?

429077 There are some that are crooked but my primary question is about the bowed boards. Primarily, do I put the board with the bow up (like the letter n) and plane the middle down to match the ends or do I put the board with the bow down (like the letter u) and plane the ends down to match the middle. The bow is fairly subtle.

jeremy romoser
03-29-2020, 4:23 PM
It would be helpful to know how thick your boards are right now.

In hand work, we would glue rough boards together, then flatten one side and joint an edge, then plane to thickness. This avoids flattening the boards individually, gluing up, and then having to flatten all over again. I also saves on material thickness.

In your case, given the size of the final board, I would think that you would want to aim for a full inch of thickness. Also you might need 3/16 or even more of extra thickness to play around with after the glue up. This probably does not leave much if any to plane off with your lunchbox planer.

Whatever you do, plane only the high spots. If you go over the whole board planing crosswise, or planing both diagonals like some beginners on U-Tube, you are planing low spots and diminishing the final thickness you can achieve.
thank you for this info. You saved me a lot of time.
Just to be clear, when you say gluing the rough boards, you mean after I joint the edges to glue together?
So I need to joint the edges to be glued, glue them together then flatten the whole desk top as one?

Warren Mickley
03-29-2020, 4:56 PM
Yes, joint the edges and use winding sticks and straight edge on the edges to make sure they are flat. Then with one board in the vise, lay the other on top and make sure the two boards fit nicely without gaps or rocking. If one board is humped in the middle, so they rock, just plane the high part in the middle. Don't keep planing the whole length and expect the plane to correct the problem. Also while one board is balanced atop the other, check that the two faces form as flat a surface as can be done by working the edges. I would glue one joint at a time.

Charles Guest
03-29-2020, 5:19 PM
I see that you're trying to glue up a large panel. If the boards are bowed in the faces, end to end (not crooked along their edges) then joint the edges normally, then arrange the boards to achieve your cosmetic goals for the panel, do a test clamp up but also adding battens on the top and bottom of the panel in three or four places depending on the length of the panel. If the edges look good, tight on the ends, and moderate pressure closes them up all along their length with no gaps then you're good to go. Put wax paper between the battens and the panel and do your glue up. Let the glue dry for 24 hours then process the panel as a unit - out of wind and flat in length and width. This will work even if your boards are not all exactly the same thickness, but not if they're wildly different which I assume is unlikely.

Here's what it would look like in a set of Plano racks. All you're doing is replicating this with bar clamps and battens, but likely horizontally. The Plano racks clamp from the edges and from the top and bottom simultaneously.

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David Eisenhauer
03-29-2020, 5:51 PM
Question for Warren: By gluing one joint at a time, does that eliminate your use of cauls or is there ever a time you use cauls to help even out hi/low on a panel glueup?

Warren Mickley
03-29-2020, 6:22 PM
The reason I recommended one at a time was that these boards were not really flat and so the edge joints needed to be made so the boards line up as well as possible. I put a straightedge across the faces with one board balanced on the edge of the other. Also I thought for Jeremy the idea of making four joints at once with 60 inch boards was a bit much for someone without a lot of experience.

I am generally doing a glue up with 1/8 inch or more of thickness to spare, so I am not trying to coax pieces into conformity with others. Sometimes I have to repair a joint that has failed on a piece of furniture. In that case there is sometimes a lot of extra clamps or whatnot to make everything come out nice.

steven c newman
03-29-2020, 6:32 PM
Hmmm...cauls are your friends..
429088
4 plank glue up...with all the clamps and cauls..and.
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After the glue up was done...

David Eisenhauer
03-29-2020, 6:52 PM
Thanks Warren. With an extra 1/8" thickness, it changes things unless you have some "firewood candidate" panel material to deal with. I like to do one joint glueup at a time when things are less than fairly perfect as well, but do use cauls as a mostly default setting when doing a multi joint glueup.

Rafael Herrera
03-29-2020, 8:12 PM
Question: given that his boards are bowed, why are you all not recommending get rid of the bow first? Using cauls to force them flat, even if that's possible with his boards, would result in a panel with internal stresses that may lead to failure over time?

jeremy romoser
03-29-2020, 8:38 PM
Warren: Thank you for your advice. Looks like my next step then is to rip the boards to proper width then dress the edges for glue up as you state. You saved me a lot of time from the way I thought I was going to do it. I don't have winding sticks or a vice, yet, would think I could make winding sticks pretty easily out of the scraps I have laying around. Also, you asked earlier but I didn't answer...the boards are currently 1 1/4". Hopefully when done, the finished top will be at least 1" thick.
Charles and Steve: I appreciate your helpful responses too. I don't have a plano press but did order and am awaiting the arrival of 3 sets of veritas panel clamps which appear to be a similar idea as the plano clamps. Some of the boards are bowed in the faces. What everyone has suggested makes sense to me now. I was stumped trying to figure out how planing the bow out was actually going to get rid of the bow.

To all: I intended to use dominos on my edge glue ups...thoughts? necessary? helpful? Waste of time?

Armed with more knowledge...back to the shop I go...

Charles Guest
03-30-2020, 4:49 AM
Warren: Thank you for your advice. Looks like my next step then is to rip the boards to proper width then dress the edges for glue up as you state. You saved me a lot of time from the way I thought I was going to do it. I don't have winding sticks or a vice, yet, would think I could make winding sticks pretty easily out of the scraps I have laying around. Also, you asked earlier but I didn't answer...the boards are currently 1 1/4". Hopefully when done, the finished top will be at least 1" thick.
Charles and Steve: I appreciate your helpful responses too. I don't have a plano press but did order and am awaiting the arrival of 3 sets of veritas panel clamps which appear to be a similar idea as the plano clamps. Some of the boards are bowed in the faces. What everyone has suggested makes sense to me now. I was stumped trying to figure out how planing the bow out was actually going to get rid of the bow.

To all: I intended to use dominos on my edge glue ups...thoughts? necessary? helpful? Waste of time?

Armed with more knowledge...back to the shop I go...

You typically don't need to reinforce the edges in a panel glue up, but in the instance of bowed lumber they might provide an assist with alignment - dowels would, but I'm not sure about the Domino system as they are wider and I've never used them, they might make alignment harder. Do a dry run after you get the Veritas clamps to see if you think you'll need anything to help getting things aligned. I doubt you will.

Prashun Patel
03-30-2020, 10:17 AM
I sometimes use Dominos to assist in alignment and to prevent squirreling around during glue up of very large pieces - but not to correct a twist. More than likely, forcing it into alignment on one edge will cause a force somewhere else.

lowell holmes
03-30-2020, 10:20 PM
I would run it through the planer bow up and then thickness plane them.