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BJC

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If you are talking about on the floor? Rugs are one of the last thing I'd want on my shop floor. Nothing but dust collecting tripping and fire hazards.:eek:
Yes, area rugs on the floor.

I have bad legs, but have never tripped on any of the rugs. The sanding dust is easily vacuumed out, the aluminum drill debris does not get imbedded into my shoe soles, and almost all of it is vacuumed out with a good household vacuum cleaner made for rugs. My shop vac does not do an acceptable job of cleaning the rugs (the message in post #137) and it is a PITA to use compared to the Oreck.


BJC
 

BJC

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When you need to drill over 300 rivet holes in aluminum hinge, setting up a simple jig is worthwhile. I marked this hinge before I decided to make the spacing jig. None of the rivets will be visible on the exterior of the airplane.
CDF64D62-DD90-4CD4-8EF3-9F85B8FFAD7E.jpeg

BJC
 

BJC

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Question on riveting.

I’m ready to rivet a piano hinge half to the inner side of a curved upper cowling. Will the riveting try to straighten the curve? Will it try to increase the curvature? Will it have no effect? If it does tend to change the curvature, is there a technique to minimize it?

0886DE96-E1FC-47B0-A902-54F6A9EE169B.jpeg

Thanks,

BJC
 

gtae07

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Question on riveting.

I’m ready to rivet a piano hinge half to the inner side of a curved upper cowling. Will the riveting try to straighten the curve? Will it try to increase the curvature? Will it have no effect? If it does tend to change the curvature, is there a technique to minimize it?
In my experience (piano hinges riveted to fiberglass cowls is the blueprint RV method, and it's what we did on Dad's airplane), it won't really change anything. There might be a tiny bit of localized deformation of the hinge from riveting, but if you're using solid rivets and a squeezer I wouldn't expect anything noticeable. The cowl will still pull into shape just fine. If you want, you could even manually pre-bend the hinge a bit to more closely match the curvature but I don't think it'll make a difference. I'd just be careful not to over-squeeze the rivets because you could crack the fiberglass. A hand squeezer is best, IMO, but it can take some forearm strength to set 1/8 rivets.

One thing we did, that might or might not make a difference, is we roughened and bonded the hinge to the cowl with epoxy as well as installing rivets.
 
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BJC

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Thanks, ‘07. I’ve used a hand squeeze to set lots of solid rivets in fiberglass, so I know that the 1/8th inch take a good effort to squeeze. The hinges have a slight bend, but don’t totally conform. I have bonded hinge in place, but will skip it this time. It is messy, and I have the exact fit that I want. I appreciate the input.

My local expert aircraft builder also looked at it this morning and provided input. He thinks that it will not change the shape of the cowling. Before he retired, he built and sold carbon fiber cowlings that are held together with piano hinge, so he has directly applicable experience, too.

Thanks,

‘70
 

rv7charlie

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BJC,

Are you using epoxy on the 'glass' side hinge stock? I'd strongly advise it. Drill 1/8 or larger holes in the hinge between the rivet holes, and mix flox with the epoxy, to help give the epoxy something to grab. Cleco the hinge in place with the epoxy, and allow to cure before setting the rivets.

Reason: the glass interior finish is relatively uneven, compared to the aluminum structure on the other side of the hinge. If you have free hinge pin movement with the hinge cleco'd in place, squeezing the rivets will deform the hinge stock to conform to the 'glass, distorting it and causing the pin to bind. If you bed the hinge in epoxy/flox *and let it cure first*, then the hinge won't deform when riveted. The epoxy/flox will also save a ton of grief down the road at 100-200 hours of flying, when the softer 'glass' starts to loosen around the rivets and the rivets start 'smoking' and eventually cracking because of the movement. Epoxy locks everything in place.

*Many* RV guys have paid the price of not using the epoxy.

FWIW,

Charlie
 

BJC

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Thanks, Charlie.

The hinge fits smoothly to a bed of resin, cabosil and milled fiber. The relatively stiff glass cowling under the bed is about 1/8” thick.


BJC
 

rv7charlie

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Sounds similar to a typical RVx cowl. The RVs use 3/32 rivets; much lower load on the 'glass' when squeezing. You can purchase softer rivets, to help avoid crushing the 'glass. I didn't need them using 3/32, but squeezing standard structural 1/8 in 'glass may well cause fracturing in the 'glass as they expand. As others have said, as long as the hinge stock conforms well to the curve prior to drilling, the riveting operation should have no effect on cowl fit (hinge distortion is another story, covered earlier).
hinge closeup (Medium).jpg

Charlie
 
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FinnFlyer

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Do notice that Van uses a smaller hinge pin in the curved hinges. I think it may be 0.093 in hinges designed for 0.125 pins.
Yes definitely drill 3/16" or 1/4" holes in the hinge between the rivet holes for epoxy/flox to flow through, as called for in the plans.

Finn
 

rv7charlie

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1584201714737.png

Above from the construction manual, pg 12-3, of my '03 vintage RV7 (didn't see it on the plans sheet, but definitely in the instructions).
 

gtae07

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One little trick that really helped on my engine build:

I purchased serviceable major components of an O-360-A1A (case, crank, cam, tappets, gears, etc.) and set about ordering all the parts I needed to build it, referencing the IPC (do note, the oil pump drive shaft in Figure 10 item 4 is not listed for many engine models, but you really do need one! Part number is 61174).

As all the parts and hardware came in, I placed them in clear plastic bags labeled with part number and the IPC figure and item numbers. Then I put all the parts for each IPC figure into a box labeled with that figure number. This made it really easy to inventory everything and easy to find them during the assembly. This kind of OCD organization is not typical for me--my shop could be described as "organized chaos"--but it was the best way I could think of to do it.
 
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BJC

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Guys, I'm not building an RV, and my plans / instructions do not indicate the holes you have recommended.

I'm not disagreeing with what you are saying wrt the RV, only that my installation is different.

BJC
 
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