I'm about to begin installing the flange on my firewall for a 1/4 turn attachment system (Mil Spec). I'm wondering if it's necessary to radius the flange at the bottom corners of the fuse or could I make two straight unbent flanges one for along the bottom of the fuse and the other for up the side? I plan to scallop the flanges and except for leaving a radius piece of the flange intacked to support the cowling I don't see a real need to make the flange one piece since I wont be putting a fastener in the radius. Any thoughts would be a help. Links to builder sites with examples would be a really big help. Thanks
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¼ turn flange question
- Thread starter Rivethead
- Start date
My opinions having done this:
Separate pieces for bottom, sides, and top. DON'T scallop the sides, I did and have considered redoing it after 200hrs. The top rear corners of the bottom cowl get caught in the scallops when installing the cowl. No need to have any flange material around the bottom corners.
Separate pieces for bottom, sides, and top. DON'T scallop the sides, I did and have considered redoing it after 200hrs. The top rear corners of the bottom cowl get caught in the scallops when installing the cowl. No need to have any flange material around the bottom corners.
Awesome, Thanks for the quick reply. No scallops..OK, I'll take that as good constructive information. What about scallops across the top, they look so cool it seems a shame not to have a few.
Yeah, the scallops work fine across the top and on the bottom pieces.
alpinelakespilot2000
Well Known Member
Awesome, Thanks for the quick reply. No scallops..OK, I'll take that as good constructive information. What about scallops across the top, they look so cool it seems a shame not to have a few
You pretty much have to scallop at the top. If you don't, the attach strip will tend to angle up, preventing the cowl from laying flush.
dhall_polo
Well Known Member
No penalty for scalloping everywhere.
I just finished doing Skybolt fasteners. I posted pics of my camloc install to my website.
I went with a "no hinge" cowling, and I'm very happy so far with the Skybolt camlocs and installation. As others have said, scalloping is required around the top cowling, but you should be able to get by without scalloping everywhere else. The bottom flanges do angle upwards a bit, but they do so uniformly.
I've read about how others have not enjoyed hinge installation or the user-friendliness of the hinges thereafter. I thought the Skybolt camloc install was straightforward. Granted, it was a fair amount of work. It reminded me of doing the 1000 platenuts on the wing spar. Lots a repetitive steps, rinse, repeat.
At the very least, there's a modest weight advantage in scalloping as it removes a lot of excess metal. I think it looks better with the scallops, but that's subjective, and not many will ever see it. The fit around the front of the cowling is tight, and maybe it would be harder to install/remove the cowling with unscalloped trim along the sides.
One thing I would modify from Skybolt's instructions: They have you cut 4" wide attach strips to start with, and then you trim excess later. I think that was a great waste of material. 3" wide would be plenty.
Good luck!
I just finished doing Skybolt fasteners. I posted pics of my camloc install to my website.
I went with a "no hinge" cowling, and I'm very happy so far with the Skybolt camlocs and installation. As others have said, scalloping is required around the top cowling, but you should be able to get by without scalloping everywhere else. The bottom flanges do angle upwards a bit, but they do so uniformly.
I've read about how others have not enjoyed hinge installation or the user-friendliness of the hinges thereafter. I thought the Skybolt camloc install was straightforward. Granted, it was a fair amount of work. It reminded me of doing the 1000 platenuts on the wing spar. Lots a repetitive steps, rinse, repeat.
At the very least, there's a modest weight advantage in scalloping as it removes a lot of excess metal. I think it looks better with the scallops, but that's subjective, and not many will ever see it. The fit around the front of the cowling is tight, and maybe it would be harder to install/remove the cowling with unscalloped trim along the sides.
One thing I would modify from Skybolt's instructions: They have you cut 4" wide attach strips to start with, and then you trim excess later. I think that was a great waste of material. 3" wide would be plenty.
Good luck!
sprucemoose
Well Known Member
Scott knows of what he speaks regarding the bottom cowl hitting the scallops along the side of the firewall. Not a major issue but a PITA when installing the lower cowl solo.
You will need to scallop the top, as it curves down slightly and it is easier to bend the individual scallops. I made mine from a bunch of 1-foot sections, made it much easier to work with.
Some pics here:
http://home.mindspring.com/~rv6/RV6site/plenum.htm
You will need to scallop the top, as it curves down slightly and it is easier to bend the individual scallops. I made mine from a bunch of 1-foot sections, made it much easier to work with.
Some pics here:
http://home.mindspring.com/~rv6/RV6site/plenum.htm
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frazitl
Well Known Member
At the same place as Mr. Rivethead
and I'm using Milspec fasteners. Look very similar. They only call for 1 1/2" flange with a 5/8" spacing from the edge of the fiberglass. What dimensions did you guys end up with? I'm a little concerned with the camlocs that close to the aft edge of the fiberglass.
and I'm using Milspec fasteners. Look very similar. They only call for 1 1/2" flange with a 5/8" spacing from the edge of the fiberglass. What dimensions did you guys end up with? I'm a little concerned with the camlocs that close to the aft edge of the fiberglass.
Watch that your placement of the receptacles above and below the upper engine mount attach points allows room for the receptacle - so it doesn't foul the engine mounts. I expect this would also be a concern about the lower outboard bolts if you're using 1/4s on the lower cowl sides. If using hinges on the sides, provide a scallop relief above where you must withdraw the pins vertically.
Drill #40 tooling holes and cleco the cowl to the strips when fitting. It's much faster than trying to use the 1/4s at this stage. Also, it precisely relocates the cowl each and every time (there will be many) you remove/replace. Match drill 1/4s' centers last thing.
John Siebold
Drill #40 tooling holes and cleco the cowl to the strips when fitting. It's much faster than trying to use the 1/4s at this stage. Also, it precisely relocates the cowl each and every time (there will be many) you remove/replace. Match drill 1/4s' centers last thing.
John Siebold
dhall_polo
Well Known Member
I used 5/8" center to edge and 1-1/4" flange on the firewall.
I used 7/8" centers and 1-5/8" flange on the horizontal lines. Only reason I used a little more was for a little more separation between the 2 clocs right next to each other where the lower+upper cowling meet at the firewall.
I used 7/8" centers and 1-5/8" flange on the horizontal lines. Only reason I used a little more was for a little more separation between the 2 clocs right next to each other where the lower+upper cowling meet at the firewall.
Justin.Ice2010
I'm New Here
Hi Terry. I am completing an RV6 rebuild that had Milspecs in the cowling. The original build was 2004. I am looking for the install instructions that match the original install for re-license. Milspec will only supply 2009 instructions. Do you have earlier (2003-2004) instructions? Thanks, Justin
IowaRV9Dreamer
Well Known Member
what size mounting strip for Milspec fasteners?
In the file on Milspec's website ("RVLancInsr.pdf"), it says:
The distance from the edge of the cowling to the center of the fastener hole should be a minimum of 5/8?. The total width of the support strip should be 2.5?. The overlap amount (receptacle mounting lip) should be aminimum of 1-1/8? preferably 1-1/2? and the thickness of this strip should be a minimum of .040?
I have another file that (I think) came in the box with my Milsepc parts which says:
The distance from the edge of the cowling to the center of the fastener hole should be a minimum of 5/8?. The width of the support strip (receptacle mounting lip) should be a minimum of 1-1/8? preferably 1-1/2? and the thickness of this strip should be a minimum of .040?.
I'm not sure what they mean by ""overlap amount"... is that the part of the aluminum strip that is under the fiberglass cowl? If that is 1 1/2 inches, and the aluminum strip extends under the firewall flange another 5/8" or so... sounds like 2 1/8" would be a better total width.
Any idea why one version of the instructions specify 2 1/2" total width? Also, is it necessary to use the 0.063 aluminum? Is 0.040 adequate? Seems like it would be easier to work with.
Any advice would be appreciated - I need to know what width of strips to order from Vans.
I'm about to order my finishing kit and wanted to have Vans cut the finishing strips for me. I'm confused about the width of the strips.
In the file on Milspec's website ("RVLancInsr.pdf"), it says:
The distance from the edge of the cowling to the center of the fastener hole should be a minimum of 5/8?. The total width of the support strip should be 2.5?. The overlap amount (receptacle mounting lip) should be aminimum of 1-1/8? preferably 1-1/2? and the thickness of this strip should be a minimum of .040?
I have another file that (I think) came in the box with my Milsepc parts which says:
The distance from the edge of the cowling to the center of the fastener hole should be a minimum of 5/8?. The width of the support strip (receptacle mounting lip) should be a minimum of 1-1/8? preferably 1-1/2? and the thickness of this strip should be a minimum of .040?.
I'm not sure what they mean by ""overlap amount"... is that the part of the aluminum strip that is under the fiberglass cowl? If that is 1 1/2 inches, and the aluminum strip extends under the firewall flange another 5/8" or so... sounds like 2 1/8" would be a better total width.
Any idea why one version of the instructions specify 2 1/2" total width? Also, is it necessary to use the 0.063 aluminum? Is 0.040 adequate? Seems like it would be easier to work with.
Any advice would be appreciated - I need to know what width of strips to order from Vans.
