>My first bridge that I will be gluing on has rib spacing varying from >about six inches to three inches apart. My understanding is that you >suggest that one screw/button placed every three to six inches (mid way >between each rib) along the bridge will provide sufficient clamping for a >Tightbond joint? Yes, it always has. >Might the fearful feel better if a larger block of wood is used >temporarily instead of a button? You can if you like, but it won't measurably improve the joint. Truly, it works just like we said, and produces a joint that far exceeds the minimum physical requirements for that joint. >With your process do you see good glue squeeze-out mid-way between screws >(as in on the top side of the board at rib locations)? Yep. You know the bridge isn't going to deflect much in that 6" span, and that 8mm spruce panel isn't going to let the resistance offered by a small pool of Titebond bend it enough to spoil the joint either. Not by a long shot. >Maybe part of my problem is I am imagining this floppy panel - but I >suppose it won't be so floppy after ribs are attached. Yes, the ribs make it stiffer in the direction in which it was floppy, and in the other direction, it never was floppy enough to be a problem. Wave that panel around some after you get the ribs on. Pound on it. Push on it. Try to bend it (careful of the edges, and don't dent it up). Marvel at how something that relatively light can be that stiff. That thing becomes it's own clamping caul. Ron N
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