I’m about to finish a new fireplace mantle and am wondering if I can safely glue down the top without risking it cracking due to expansion. I would attach it with wooden buttons, the way I do table tops, but it has to slip over an existing unremovable solid beam mantle. The top is cherry and will be only about eight or nine inches wide, so my thought is that it won’t move that much. The top will sit on a three sided built up moulding about two inches wide along the top edge with an overlap of about half an inch. Think of a table top six feet long by nine inches wide by 3/4 thick glued down on three sides.
Discussion Forum
Get It All!
UNLIMITED Membership is like taking a master class in woodworking for less than $10 a month.
Start Your Free TrialCategories
Discussion Forum
Digital Plans Library
Member exclusive! – Plans for everyone – from beginners to experts – right at your fingertips.
Highlights
-
Shape Your Skills
when you sign up for our emails
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. -
Shop Talk Live Podcast -
Our favorite articles and videos -
E-Learning Courses from Fine Woodworking
-
-
Replies
I would just glue the back of the top to the build-up. This will keep the top in place yet still allow for expansion and contraction.
Jim
The problem is that on the three sided frame, the back is the missing 4th side. Another problem is that the weight of the entire mantle is held by the top resting on the existing beam mantle. Thanks for the quick reply, though.
Use construction adhesive
Use a construction adhesive that remains somewhat flexible, instead of a glue that hardens completely. Large adhesive surface = very strong bond.
I guess what I'm really looking for is how much could an eight or nine inch wide cherry board be expected to expand. I'm thinking not enough to make a difference. I've seen two of my breadboarded table tops, one oak and one cherry, expand a quarter of an inch across a forty inch wide top, so I still have some concern.
shrinkage calculator
Open this link, put the specifics into the boxes, and get an answer which is better than guesswork.
http://www.woodweb.com/cgi-bin/calculators/calc.pl?calculator=shrinkage
This is one of those "tools" that is very useful to have in your favorites box.
This forum post is now archived. Commenting has been disabled