b.bixel

My Feedback: (123)

Any problem with using wood screws to mount an engine mount to a firewall versus using blind nuts and bolts?

khodges

My Feedback: (1)

I've seen some old planes done this way, they were all about .40 or smaller. Eventually, though, they're going to work loose. If you try it, use at least #8, and go long enough that they completely penetrate the firewall. You could put a little epoxy in before you place the screw, or a little silicone sealer to help hold it tight.

piper_chuck

My Feedback: (12)

Yes, there is a big problem using wood screws instead of bolts and nuts. You may have a close encounter of the painful kind with your prop when the wood screws pull out. Engines create a large amount of stress. Bolts with lock nuts and washers, or blind nuts, inside the firewall ensure that the engine mount will stay connected to the firewall.

Ed Smith

Calculate the cost and building time of your airplane, engine and radio. Do you want all of that hanging on four little wood screws?

Ed S

Cyclic Hardover

My Feedback: (3)

Yes , there is a problem. Shortcuts like this can get people hurt. Also when others find out what you have done, don't act surprised when nobody comes to you looking for advice.

flipstart

Its just not a good idea-no cost savings and T-nuts with socket head screws just give you one less thing to worry about-I am always careful not to let anything sharp protrude thru the firewall that might cut a hole in the tank-those sheet metal screws that come with a lot of mounts always get put back and mount drilled and tapped for socket head screws to mount the engine. 2-3 sizes of allen drivers and you can dissassemble entire plane, from engine to control horns. Just makes life a little simpler. Flipstart