My Father's RV-4 Project
Sat Sep 19, 2009 12:47 am
I just wanted to share some current pics of my father’s RV-4 project. The firewall forward is pretty much buttoned up now, and he's on to the cockpit and finishing out the fuselage interior. This is the seventh year of effort toward getting the little thing airborne. We had to build the shop before we could build the plane though. 
Sat Sep 19, 2009 8:48 am
Lookin' good, Rob. Be sure to update us when it takes to the air!
Gary
Gary
Sun Sep 20, 2009 3:26 pm
Looks like you did one heck of a good job on both the shop and the airframe! NICE JOB!!
I'd recommend seperating your ingition harness leads for a couple of reasons, one is induction, with the wires clamped together you could induce voltage into the other wire from the plug the mag wants to fire. Also, chaffing can be an unseen issue from the insulation minutely rubbing back and forth from engine harmonics, I recommend that you 'butterfly' your clamps and not run both wires in the same ADEL clamp. If you use a short spacer between the clamp and the rocker box cover for clearance, and place the clamps back to back the routing is just as neat and much safer. Also place firm silicone or rubber spacers (pieces of spark plug boot from HEI auto plug wires work well for that) on the leads and remove the Panduits on them (the outside world calls them 'zip ties') then panduit them around the spacers snuggly but not 'cut off your oxygen' tight. If you can find it, use SCOTCH 70 wire wrap @ clamping points, it's a grey rubbery tape that sticks to itself and is used on the 787 to insulate wires (including fiberoptic) where they are clamped, just a couple of 'pull it snug' wraps will work. (costly but cheap insurance)
Also keep your leads off of edges and away from sharp corners, chaffing can ensue and you are less likely to cause overheating in the strands from trying to 'push' the amperage around a sharp corner in the wire, electricity flows along the outside of the indivdual strand not the core of the strand and heat buildup can be an issue, plus a graceful curve is more organic looking than hard, sharp angles @ every turn or corner.
Sorry if this came out a long winded or preachy, just safety issues I've encountered over the years.
I'd recommend seperating your ingition harness leads for a couple of reasons, one is induction, with the wires clamped together you could induce voltage into the other wire from the plug the mag wants to fire. Also, chaffing can be an unseen issue from the insulation minutely rubbing back and forth from engine harmonics, I recommend that you 'butterfly' your clamps and not run both wires in the same ADEL clamp. If you use a short spacer between the clamp and the rocker box cover for clearance, and place the clamps back to back the routing is just as neat and much safer. Also place firm silicone or rubber spacers (pieces of spark plug boot from HEI auto plug wires work well for that) on the leads and remove the Panduits on them (the outside world calls them 'zip ties') then panduit them around the spacers snuggly but not 'cut off your oxygen' tight. If you can find it, use SCOTCH 70 wire wrap @ clamping points, it's a grey rubbery tape that sticks to itself and is used on the 787 to insulate wires (including fiberoptic) where they are clamped, just a couple of 'pull it snug' wraps will work. (costly but cheap insurance)
Also keep your leads off of edges and away from sharp corners, chaffing can ensue and you are less likely to cause overheating in the strands from trying to 'push' the amperage around a sharp corner in the wire, electricity flows along the outside of the indivdual strand not the core of the strand and heat buildup can be an issue, plus a graceful curve is more organic looking than hard, sharp angles @ every turn or corner.
Sorry if this came out a long winded or preachy, just safety issues I've encountered over the years.
Tue Sep 22, 2009 8:29 am
Makes sense, and thanks for the insight 
I'll pass it on when I get back to the shop next weekend and see what we can do about it.
I'll pass it on when I get back to the shop next weekend and see what we can do about it.