January 30, 2005

Brian's Bird

Brian Mayette is moving along on getting his RV-7A done for Oshkosh this summer. He called and asked for some help riveting some pesky rivet locations for the canopy. It turned out to be an opportunity to scope out the details on the canopy and to mill one of my bucking bars to do the job... Which will be coming up on ours as our finishing kit is scheduled for shipment in late March.

Brian is building a IFR panel, and has lots of the mega-bucks hardware required including a Blue Mountain EFIS with a 10-inch display... So I took the opportunity to get an intel photo and a good look at the part markings. It looks to be a industrial grade display, may also be of Rockwell manufacture, but I don't think so.

Meanwhile in my vacuum cleaning of information sources I have found a chinese 10" TFT display for automotive applications. If you search the net for automotive VGA displays you'll find there is a growing source of components including small form factor 1.1 gHz CPUs that are Linux friendly.

January 25, 2005


Not the best screen shot, but if you squint... or plug in the URL yourself you can see what the Cumulus folks are up to. They and lots of other folks are having a cow about the federaly's attempts to pull their (our) databases back.

After some snooping it looks like the feds are stupid enough to think they can retract information on federal airway locations et al... Well duh, how you going to navigate? It'll be interesting to see what the bureacrats screw up. Meanwhile, back at the ranch we've been busy soaking up every terrrain database we can ger our hands ...er, disk drive on.

The recent AOPA magazine had a nice article on glass panel technology including noting that Chelton uses the crossbow sensor for its solid state gyros. Crossbow had a booth last summer at Oshkosh and I expect them to be there again this year. Last summer the sensor was $10k and it's now $7.5k... We'll see where they go with the price.

At this point it definitely looks like the glass panel stuff is an integration of sensors and software and ...more on the software shortly.

January 21, 2005

Terrain Avoidance

Just a quick note to let everyboy know I haven't fallen off the fusalage on working on the plane but have been doin a little "snooping". This is a screen shot of a Linux-based application from Germany called KFlog, used by glider pilots.

I've done a little quick hack to it to force the mapping to put everything 500 meters and above in red... i.e. terrain avoidance. The image is centered over the general vicinity of Lebanon Airport (KLEB). I think I can hack the software so with a laptop and GPS plugged in you can get the poor man's version of terrain warning.

I'm also working on a little technical investigation to see about using the open sourced flightgear software for a HDD (head down display vs HUD) complete with with the artificial horizon indicators. I've already found an airline-grade sensor package which I've previously looked at at Oshkosh but at $7500 (down from $10k this summer) it's still too expensive.

Anybody got a price on the DYNON sensor?

January 16, 2005

Sound Effects

Finished all the detail drilling on the roll bar today. I have to primer a few parts before I can do the final pop riveting of the back row of rivets.

Once the roll bar was pretty much done it was time to go back and start cleaning up my endless punch list of miscellaneous items that need to be done - like countersinking some forward fusalage areas and assembling the various platenuts to hold the sheet metal on in the cockpit.

Besides doing the traditional RV "sit in it and make airplane noises" once in a while, I thought I'd do some goofing-off pasting together some panel ideas for starters.

January 13, 2005

The Mascot

The moose mascot has now moved from the wing load carrying bulkhead to the top of the roll bar.

Drilling the roll bar assembly is pretty straight forward ...after you fit the mounting brackets, which I did by flycutting them to match the outside contour of the fuselage. The flycutting operation worked great, as evidenced by the detail photo of the final fit.

My niece has been keeping the weblog up to date for me - And it turns out a co-worker of her husband is an RV-6 builder, EAA tech counsellor, and DAR in SoCal. That last photo is of Gary Sobek's beautiful RV-6 taken on a trip to the Bahamas!

January 12, 2005

Muscle Memory

Let's see if we remember how to rivet...

During the course of the day I managed to rivet on the roll bar using: (a) back riveting - didn't like the results but got me started; (b) squeezing rivets manually with the avery rivet squeezer; (c) the ol' rivet gun with bucking bar on a few; and my favorite when I can get the tooling to work out (c) the pneumatic alligator squeezer.

The pneumatic squeezers, alligator, or conventional type sure look like a luxury item in the beginning (and to spouses) but boy, once you get used to using 'em they sure start to look more and more like a necessity. Not only are they easier on your hands, but they're more consistent than you could ever be... With the possible exception of my trick: Using my body weight to press a manual squeezer with the squeezer mounted in a mill vise!

The first photo is courtesy of Dino Vlahakis, from when he and and Tom visited yesterday. They actually caught me smiling... Good work! I'm more light natured than I usually appear, but photos don't catch the "class clown" side too often.

Anyhow, I finally got to tackle the tougher riveting on the roll bar and found I could really tighten the joints up between the parts by using a pair of welding-type vise grip clamps to straddle the rivet being squezzed and make sure the spring between the parts was closed shut. There's only so much a rivet squeezer and bucking bar can do if the part alignment is a problem when you pull the trigger. I have the right (port) side mount drilled on the fusalage and the left (starboard) is clamped when I shut down tonight.

I'll do some drilling on the left mount tomorrow, hopefully, then work out the bracket drilling details between the roll bar and the bulkhead. After that, I can rivet the brackets to the aft side of the roll bar with solid rivets as opposed to the alternative pop rivets Van's specifies- i.e. if you do an oops and trap yourself. Whenever possible, I opted for the solid rivet specs over the pop rivets, it's sort of a let's see if we can solve this puzzle.

January 11, 2005

Prime Time

Boy, I could kick myself! I got a visit from Tom Williamson, our EAA Chapter's past president, and Dino Vlahakas a tech counselor. They took MY picture with the fusalage but like a dummy I forgot my camera and didn't get THEIR picture for the log!

Oh well, back to work... I did a fast heating of the garage and shot some primer on most of my backlog basket of sheetmetal. After the parts tack up (and the garage temp starts to go south again) I generally "hang the laundry" to cure in the workroom.

Come to think of it, I may be able to do some riveting on the roll bar tomorrow when the primer finishes curing.

January 10, 2005


Sunday started with some deburring of the small mound of parts queue'd up for priming. I finished the deburring this morning and noticed I had to do the detail milling of two slots in the sheet that covers the front of the fusalage for the tip-up canopy and do one more dimpling session.

Work space is getting a tad cramped in the house sometimes so for the dimpling I just set the press on the floor in a storage room and used my boot to support the sheet. Now if we get some warmer weather I'll stoke up the garage and prime some parts.

Meanwhile back at the ranch, we put in the finishing kit order.

January 07, 2005

Sunny Day

Got my brackets done, and the roll bar looks like it will fit nicely in the space alloted in the fusalage. Now its the deburr - dimple - prime - rivet - work on the roll bar assembly so I can do the final fit up of the brackets.

I have a large inventory of parts that are waiting for deburring and priming from the front of the the fusalage. Since we're supposed to have a heat wave for a bit next week I'll be concentrating on deburring and dimpling various parts for a priming session in the garage... Assuming I can get things warm enough for the primer.

Anna the cat is back this winter as the shop superintendent!

January 06, 2005

Shop Math

The brackets for the roll bar have lots of angles specified in the plans. It was a nice diversion to do a little "shop math" to figure out where the hole coordinates are so I could write the NC programs, check the fit-up on the fusalage and then back out to the shop to drill the holes and start milling all those odd angles. Didn't quite get all the brackets done, but I took my time. I'd rather not machine the bracket blanks twice!

January 05, 2005

The Details

Now that I have the basic roll bar assembly drilled it's time to work on the drilling, milling, and bending details. The milling of the 1.5" hole was pretty straightforward as long as you fabricate the wooden block to support the work in the vise. The one bracket requires bending a section of 1" x 1" by 1/8" channel to 101 degrees which takes a lot of "oomph" courtesy of the mill vise on the Bridgeport milling machine.

January 04, 2005


The plans call for the width of the roll bar to be 1.5 inches. I used wooden spacers between the sections and C-clamps to hold everything into position and get the width right as the parts want to wander all over the place. Now that the drilling is down I'll have to clean the disaster area in the dining room. The wooden jig table worked out very well. Next I'll be working on the various attachment brackets, some of which look pretty tricky to fabricate.

January 03, 2005

Bar Roll

Was just a tad icy today. Even the black lab puppy was slippin' and slidin' ...Note the fashionable NH footwear Cathy has on - crampons!

Drilling the roll bar assembly. I made a jig to hold the parts in alignment while drilling that seems to be working out pretty good. We'll see when the rest of the holes are all drilled.

January 02, 2005

Roll Bar

Some unfortunate folks have gone on to find out the roll bar on an RV actually works!

Decided to avoid the wrestling match of trying to hold various pieces in alignment by hand and built a fitting and drilling jig. Got a little NC work done in the form of drilling the splice plates. I had to run a heater in there for a while to get the temp up to about 55 from 30.

I still have to finish all the strip drilling to mate the front and back halves and mill a 1.5" dia. hole on the two ends of the rear section of the roll bar for fastener access later on assembly. Enjoyed making the jig.

The idea came to me in my sleep: a bad old problem solving habit from when I developed software... Usually got a stiff neck from debugging in my sleep!

January 01, 2005

Little Breezy

New Years Day started out in the 30s so we decided to climb Mt. Cardigan. It was blowing the usual gale force winds on the summit. With the wind chill you could feel the core heat being sucked out of you. It was definitely a day to crank the section to the summit above tree line, reset gear in the lee side of the fire tower, then beat feet out of there back to treeline.

On the RV-7 front, I am re-checking measurements and doing some more planning before machining roll bar parts. Hopefully tomorrow we can drill the splice plates for the roll bar and get the main pieces trimmed to size.