Popular Woodworking 2004-02 № 139, страница 19
Q & A MDF is Inexpensive, But it's Not Sturdy Is MDF Strong Enough to Prevent My Shelves from Sagging? I am getting ready to make some inexpensive garage cabinets and I was considering using 3/4" medium-density fiberboard (MDF) for the case sides and shelves. The shelves will be 18"-24" deep and about 36" long. I am planning to use dados in the case sides to support the ends of the shelves; and I'll reinforce the shelf with a piece of 1"-wide hardwood along the front attached with biscuits. Will the dados in the sides be strong enough to support the shelf ends? Will the shelf sag over time? Would I be better off with birch plywood? Jeremy Graham Bend, Oregon While the dados will be OK, 36" is a mighty long span for MDF, even with the "dropped edge" detail that you plan to add. The maximum span for MDF without a dropped edge is 32". With the addition of a 3/4" dropped edge, a 36"-long MDF shelf will sag unacceptably with only 90 pounds on it - that's not much for a garage cabinet. Yellow poplar - even without a dropped edge - won't sag until you put 284 pounds on it; yellow birch sags at 348 pounds. MDF's weakness is that it doesn't have a grain structure like solid wood or plywood. Save the MDF for shorter spans and stick to birch plywood or solid wood for your shelves. — Christopher Schwarz, executive editor Why is the Blade of My Shoulder Plane Wider Than the Tool's Body? I recently purchased a Stanley No. 92 shoulder plane. The blade is precisely 3/4" wide. continued on page 19 WRITE TO US Every day we get questions from readers on all subjects about their woodworking. Some are letters; many are e-mail messages.We are more than happy to share our woodworking experience with you by answering your questions or adding some clarity to whatever aspect of your craft you are unsure about. In addition to the hundreds we answer privately every month, we want to share the best questions here with readers. Send your questions via e-mail to popwood@fwpubs.com. Or send a note by mail to: Popular Woodworking, Q&A, 4700 E. Galbraith Road, Cincinnati, OH 45236. popwood.com 17 36-312,12" Front Bevel Lock Compound Miter Saw The Dursbie Saw You Can Take From Site To Site Innovative Front Bevel Lock and detents mean no more reaching behind the saw. Lightweight, compact and durable. Easy to carry from job to }ob. Cuts 7i," base and 8V crown. For your nearest dealer, visit d e itam achinery. c o m/re b ate. Rebate valid 11/1/03 through 2/15/04. Offer not valid in Canada. Your achievement. Our tools. CIRCLE NO. 135 ON FREE INFORMATION CARD. |
