What about using epoxy?
That way you don't have to worry about clamping pressure.
From Woodweb:
Clamping pressure with epoxy adhesives
Precision joinery is one of the marks of a competent woodworker. But an obsession to achieve nearly invisible glue joints can be a liability when working with epoxies. The common adhesives that woodworkers are accustomed to working with (urea formaldehyde and resorcinol, for example) generally require tight joints, adequate clamping pressure, and warm temperatures to perform properly. These same bonding techniques are naturally used when a woodworker first starts to experiment with epoxy resin adhesives (old habits and obsessions die hard). The results are unexpected and disappointing when the resultant bond fails under light loading, and the epoxy is blamed for the problem. Most often, it's the woodworker's techniques that need to be examined.
1) Epoxy adhesives are far more forgiving when used in less than perfect working conditions.
2) They do not require tight fitting joints to successfully bond two pieces of wood. In fact, the joint strength will usually be higher if the joints are machined to a loose fit!
Epoxies are also used in boat building to coat and protect wood from moisture. When a coat of epoxy is applied, it actually seeps into the wood pores, providing a strong bond. This ability to "saturate" the wood fibers applies, of course, when two pieces of wood are bonded. If you plan to stain prior to applying finish, be sure to apply the stain in the bonding area before gluing. Otherwise, the epoxy "squeeze out" will coat and saturate the surrounding wood, effectively preventing stain penetration.
A No-Pressure Situation
Why does a woodworker often experience failures when using epoxy adhesives? They use clamping pressure (as opposed to simply closing the joint) and squeeze out most of the epoxy, leaving only a thin film that is absorbed by the wood. A starved joint results.
When bonding with epoxies, clamp to close, and no more. If the glue-up will be subjected to stress when unclamped, then allow the epoxy to cure for several days before removing the clamps - epoxies continue to gain strength for a week or longer. The addition of a filler such as fine sanding dust to the epoxy will act to fill gaps. When using a filled epoxy, be sure to coat both sides of the joint with the mixed epoxy before adding the filler.
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