Piano hinge

g zero · #1 05-13-2012, 04:03 PM

Any reason to "upgrade " the piano hinge for the cowl to the extruded type ? I just used some on a biplane cowl , nice stuff , but pricey .
Tom.

Jeff R · #2 05-13-2012, 04:14 PM

I used the standard hinges for the cowling and were I to do it over again, I would use the sky bolt or the mil spec fasteners. The hinge pin technique is a huge pain leading to scuffed knuckles and scraped wrists. My hanger mate, who just started a -7, has seen my frustrations installing and removing the pins and is going with the sky bolts. More work upfront perhaps, but far easier over the long run.

Walt · #3 05-13-2012, 06:08 PM

Quote:

Originally Posted by g zero

Any reason to "upgrade " the piano hinge for the cowl to the extruded type ? I just used some on a biplane cowl , nice stuff , but pricey .
Tom.

The extruded mil spec hinge is much stronger than the other "stuff". I used it on my cowl all the way around and have zero problems. My cowl goes on an off with no effort, all pins slip in easily, no fuss, no muss.. eazy breezy

Dean Pichon · #4 05-13-2012, 06:12 PM

Quote:

Originally Posted by g zero

Any reason to "upgrade " the piano hinge for the cowl to the extruded type ? I just used some on a biplane cowl , nice stuff , but pricey .
Tom.

Rolled hinges are much more susceptible to eyelet failures. On my -4, after breaking a number of eyelets, I switched to a combination of extruded hinge and cam-loc fasteners. In my humble opinion, rolled hinges have no place on an aircraft. Given the small cost delta between rolled and extruded, I would go with extruded every time. This is one of the few places where I believe Van's Aircraft missed the mark.

Ironflight · #5 05-13-2012, 06:58 PM

Well, I know that (as others have said), the extruded hinges are better than the rolled ones - but I have had ZERO hinge loop failures on the sides and firewall hinges on the RV-8 in 1500 hours. If you take the time to fit and install everything with low (or no) pre-load, then the stresses should be minimal. Of course,e there is nothing wrong with buying extruded hinge to replace what comes in the kit....but better isn't necessary if good is good enough.

Paul