Gluing Up a Solid Oak Top From Narrow Strips
Advice on ripping, planing, sanding, gluing and clamping for a quality wood countertop. February 20, 2008
Question
I am making a couple of small cabinets with solid oak tops, approximately 27" x 18", and would like to know the right way to glue up narrow pieces to achieve this width. What is too wide of a piece to use? Should I use biscuits or not?
Forum Responses
(Cabinetmaking Forum)
From contributor V:
Do you have a jointer? I use the jointer to flatten the edges and then just use I-beam clamps and glue. Alternate the grain heart-side up, then -down. Then run it through an overhead sanding machine. Using biscuits sounds like too much time.
From contributor J:
I skip plane mine heavy, then edge, rip no wider than 3", edge glue while setting on 1" pipe clamps, tighten and allow to dry, then finish plane or sand to finished thickness. If your glue up is larger than your planer or sander, then I might do the panel in two pieces with biscuits and then sand the joint to smooth.
From the original questioner:
Yes, I do have the equipment to edge, plane and sand one wide piece. Why no wider than 3''? And when clamping, how many on 60'', and do you put clamps on top and bottom?
From contributor J:
The narrower the stock width-wise, the less room for cupping if cupping occurs. I do a lot of glue ups in a year and that's the widest I go. Anything wider I feel that if it cups down the road, it will be felt by rubbing your hand over it. As far as the clamps, yes, I alternate them from one side to the other. On a 60" piece, probably 5 clamps, maybe 6 clamps depending on the material and how good of a job you do on jointing and ripping. Make sure your clamps are flat on the work surface or that can also transfer to the glue up. I usually scrape off as much squeeze-out as I can also before planing/sanding.
From the original questioner:
Thanks for the information. I'm going to glue up a couple panels Monday.
From contributor R:
I have glued up a fair amount of panels but have never subscribed to ripping perfectly good boards into 3 inch strips or alternating growth rings. I have always gone with the width of stock on hand and match the best grain and color patterns for the best looking panel. If your wood is dried and acclimated and milled correctly, you should have no problems with warping or cupping; at least it has worked that way for me.
From contributor F:
Yes... ripping to no wider than three inches is extreme, and in my opinion unattractive - or butcherblock-ish. I do it like the guy above. I arrange the boards for the most pleasing grain and color match and disregard the growth rings orientation. I limit my board width to about 10" across the grain to minimize cupping per board. I sometimes rip wider stuff down the center and then re-glue on the center line. Some say it will still cup the same amount when glued back together, but I think it breaks the continuity of the grain and you get two cups half as extreme as the whole board would have done.
From Professor Gene Wengert, forum technical advisor:
Using narrow rips (3") is a standard operation to account for any moisture changes after gluing. However, as mentioned, wider pieces can be used if the moisture level is correct. That is usually about 6.5% to 7.0% MC. If there is no moisture change in use, then there will be no warp.
When using narrower strips, good operations will also color match, and maybe even grain match (flatsawn versus quartersawn), to achieve a more uniform look. However, many operations do not. In a few operations, I will even see them flip the individual staves end for end and also alternate the barkside (up and down) in adjacent pieces. These last two items are not necessary and do little, if any, good. Rather than spend time doing this alternating, why not just assure that the MC is correct?
To measure the low MCs, a pin-less meter will be necessary. With any meter, it is important to use it correctly; otherwise, a 1 or 2 percent MC variation from the truth is likely.
Incidentally, no one has commented on biscuits... do not use them. They are used only for alignment and do not increase joint strength.
Using a ripped edge is common, but it usually requires a SLR saw with a blade that has been side dressed properly. That is, the sides of the teeth are what prepare the surface and not the tops.
From contributor K:
To prepare edges... Line up pieces for your panel. Draw a triangle to keep pieces in order. Put an X on the right side of each board, put an X on the opposite side of board on the bottom. Run each piece over the jointer with the X side to the fence. This makes mating edges line up perfectly even if the jointer fence is not at 90 degrees. No gaps, perfect glue-ups every time.
From Professor Gene Wengert, Sawing and Drying Forum technical advisor:
When gluing off of a sawn edge, it is important to have a sharp saw, plus a fairly smooth surface. A dull saw, or one with poor tooth design for ripping, will heat and burnish the edge and that makes a weak joint. Rough surfaces will have too many areas over 0.006" apart and that will weaken the joint. My preference is to avoid an ATB type sawblade.
From contributor L:
The biscuits aren't going to help on these small tops. If you use a jointer to prepare the edges, make sure it is perfectly set up. You should be able to lay the parts in place without glue or clamps and not see any air gaps. If you have a slider, you can saw a better edge for gluing than the jointer will give. Better yet, a straight-line ripsaw. 3 1/2" strips alternate center of tree side. If you have a moisture meter, check the boards to be sure there isn't a wild one mixed in.
