Making a Workbench Top

I have been air drying some 3 1/8" x 1 3/4" maple for about 21 months now in the unheated section of my shop. This is lumber came from trees I cut and had a friend saw into lumber with his Timberking. According to what I have read, it should be dry enough to use by 21 months, although I do want to check the moisture. I didnt want to kiln dry it, because I am not sure people know how to kiln dry this thick of wood properly. I was considering having it kiln dried now, but that might be overkill or it might be good insurance.

After I square up the rough cut lumber, I was considering using at least three rows of biscuits per joint to glue the wood together. I am shooting for a final thickness of 2 3/4", but I am not sure biscuits are the right method to use.

What do you think about 1) kiln drying now and 2) biscuit method for gluing it up?

Thanks for your input.

If an alignment aid is desired, I would use a spline for a seam as long as a workbench top. A 1/4" or even an 1/8" stopped groove to house strips of 14" or 1/8" hardboard splines would do the trick. Or you could just skip it.

Can you come up with a moisture meter to check the wood? Kiln drying to finish it up may not be a bad idea and would take care of any bugs that may be in the wood. Overkill? Maybe, if it as already close to your ambient moisture in the shop.

biscuits will work, so will a spline, so will dowels. There are a lot of options. They are only for alignment and won't really add strength.

Glen and I were on the same page. I was thinking splines made of hardboard too. Must have read the same web site. That is exactly how I will do my next one.

One tip, when you square the board it's the perfect time to put in a series of square dog holes. I used my radial arm saw and cut them at a 2 or 3 degree angle.

Would it be beneficial to add threaded rod across the glued up top by drilling holes about every 12 to 16" and putting a threaded rod through it with washers and nuts? The counter bore the last piece of wood on each side for the nuts and washer and glue a thin piece on the outside to cover up the counter bores. I saw this in Wood's Labor of Love plan for the workbench top. Or is this just overkill - not giving glue the credit it deseves? So far, I have made two pieces that have split or broke and in both cases, the wood failed, not the glue joint. One was too large of panels glued up and the other project, the wood was not dry enough.

For a good Woodworking Bench Top, I definitely would NOT use threaded rods in the top, and I would just use cauls and/or a dead blow hammer to help alignment, (IF EVEN NEEDED). You can use splines OR biscuits, but I would rather just have good solid wood glued together with no internal voids except for the Dog Holes.

I agree with those folks that say the threaded rod would probably be overkill. If the wood is dry and you clean it up and glue it properly, rod just wouldn't be needed.

As for kiln drying... if it's been in your shop for that long (and it's been stickered properly all that time), it's already there. If you kiln dry it, then bring it back into your shop you will still have to let it sit there for a week or more to get acclimated to your shop if you don't want any wood movement. Do the final dimensioning right before you glue it up, don't let them sit there for even couple of days, as even normal humidity changes will cause that wood to move at least a little.

Actually, the wood is in my "cold" storage area of my shop. The shop is a pole building - 20 x 52, but only 28 of the 52 ft is heated. The unheated area stores the bulk of my wood and I bring in what I need for the next few projects to let it aclimate. In the winter time, the wood is not heated and I dont know how this affects the drying process. I assume this condition slows down the drying process.

I think that it is the first third of moisture content that can cause checking if it dries too fast and that after that kiln drying is fine. Can someone confirm this for Rich?

If you have some extra material maybe you could cut a sample a few inches in from one end of a piece and check the moisture by weight. Original weight vs completely dried weight.

The temp does not make a huge difference in drying. What does matter is the humidty in the air and air movement around the wood. I have had aspen(600 bdft) stickered in my soon to be shop for 9 month and when I took a sample to my suppleir it was 11%, which as low it will get around here.

For the glue up just glue will be fine, as the boards are wide enough to make a good strong bond.