Firewall and blind screws

[aviator_edb]

I'm about to start on the permanent firewall pieces and was wondering about the blind screw installs. I've read a lot of different solutions to the turning problem and was wondering how many folks went with Click-Bonds instead?

 

They seem like a cleaner and easier solution than some of the Rube Goldberg ideas I've read about (no offense). If I decide to go with click bonds would I mount them on the outside or would I mount them through the firewall?

[argoldman]

I'm about to start on the permanent firewall pieces and was wondering about the blind screw installs. I've read a lot of different solutions to the turning problem and was wondering how many folks went with Click-Bonds instead?

 

They seem like a cleaner and easier solution than some of the Rube Goldberg ideas I've read about (no offense). If I decide to go with click bonds would I mount them on the outside or would I mount them through the firewall?

 

Interesting question.

 

If I were to use the click-bonds, I would put them on the inside of the firewall, through the firewall. One would hope that the adhesive that you use would counteract the torque of tightening the bolts. Perhaps if you modify the shape of the flange and flox/glass over them.

 

I chose to use stainless steel thingies, from the ACE or True Value aircraft store that are designed to go through wood and provide a metal threaded recepticle. They have a flange with a female thread (kind of like a "T") and the flange has 3 tines which are driven into the firewall (from the inside).

 

These have no locking ability so that I will have to use Locktite (and safety wire).

 

One of the reasons that I chose to do this (mounted from the inside) is that your SS firewall material (or what ever metal you decide to use) will be primarily held to the firewall, sandwiching the Fiberfax, by the through the firewall bolts of the engine mount, the pulleys, and all of the other things that you bolt onto the firewall.

[rickh]

My solution was to cut two 'wings' into the wood instead of the plans full chamfer then flox fill, see attached. I trialed by attaching a nut a couple of times on a scrap piece of wood, with just finger pressure holding the screw on, no slippage. Ask me if it worked in a few years...

 

If me, I wouldn't use surface mount (surface mount clic-bond) due to potential 'under hood' temps and potential softening of the attachment glue.

 

Rick

[Phil Kriley]

My solution was to cut two 'wings' into the wood instead of the plans full chamfer then flox fill, see attached. I trialed by attaching a nut a couple of times on a scrap piece of wood, with just finger pressure holding the screw on, no slippage. Ask me if it worked in a few years...

 

If me, I wouldn't use surface mount (surface mount clic-bond) due to potential 'under hood' temps and potential softening of the attachment glue.

 

Rick

I would never rely on the attachment glue for anything I cared about. I use the plain, no-adhesive click bonds and attach them per the excellent drawings on the CozyGirrrls site.

[Big Steve]

I welded 3/4" long welding rod pieces to the heads of the screws then cut a slot in the plywood for them to fit. Covered them in Flox Might be considered Rube Goldberg but I bet they dont turn. Steve building on