Wednesday, June 30, 2010

June 2010

“XP-82 Restoration Project”
#44-83887 Twin Mustang Progress Report

Work Progress
What a good month it has been.  We were able to hire Bryan, a very experienced sheet metal mechanic to replace Jason. Bryan was very instrumental in the restoration of the P-38 Glacier Girl.  Really tired of corporate aviation and wanting to get back into warbirds, he fills a much needed open hole and is doing great.  

Horizontal stabilizer with leading edge
The leading edges of the horizontal stabilizer (two) and one vertical stabilizer are now complete and are being riveted.  (Pictures attached)  Barry (ATL) finally finished the extremely difficult four S-shaped rear fuselage forward leading edge attach angles--a miserable and time consuming job to do, but as usual they came out perfect.  (Picture attached)  

Tom and Tom riveting lefthand fuselage
One of our investor volunteers and Randall have been finishing up the last details on both rear fuselage vertical stabilizers, i.e., shooting all of the ribs, spars, bulkheads, nut plates, etc., together as two major sub assemblies prior to skinning.  One cannot believe how many parts these two tail sections have in them that needed work.

Tom Rasch and I are now full time into riveting the mid LH fuselage skins on the framework.  This is going as fast as lightening compared to the aft fuselages.  Not quite, but a lot faster.  (Picture attached)

Vic (PA) has nearly completed the number three center section spar cap and is into the fourth.  He is also making some of our spar web reinforcing angles.

Dimple machine dimpling sheet metal
We were having an impossible time dimpling 3/16” (#11) holes in 7075 T-6  aluminum without cracking the holes in the skin.   It didn’t matter if we used a hot dimpler (heated dies) or preheated the holes.  We finally cured the problem by first dimpling the hole with a 5/32” (#21) die and then following up with an #11.  Presto!  No cracks.  The original skins (24SRT) are not as hard as the required 7075 T-6 replacement aluminum which is substantially harder to form.  
Dimple dies

For readers that do not know what a dimple in the skin is, let me try to describe the process.  When one is dealing with a .040 thickness skin, the most common size on our aircraft, when using a countersunk rivet from the flush head down to the shank, it is shaped like a cone.  If one were to countersink the hole, i.e., drill a cone shaped hole in the top of the skin to fit the counter sunk head, by the time you got deep enough for the flat head of the rivet to be flush, the cone counter sink tool would have penetrated all the way through the skin, enlarging the rivet shank hole which is an absolute no-no.  The rivet shank must be a virtual zero clearance fit in the drilled hole.

Dimpling sheet metal
To correct the problem, a cone (dimple) is pressed into the skin, creating a countersink which the head of the rivet fits flush into without enlarging the hole, forming an opposite cone on the bottom side of the skin.  The underlying structure will have the matching dimple in it, so the skins will fit together with no gaps in-between, ensuring a tight rivet installation.  Clear as mud?  Just come to Douglas, and we will demonstrate the procedure of dimpling skins.  (Pictures attached)

Engine mount
We are reassembling the original LH engine mount with all of its original and replacement parts to make a fixture from--a rather quick job as everything is fitting back together very well.  We have all of the parts built for the second mount with the exception of three lower beams; one replacement for the corroded lower left beam for the left mount and the two lower beams for the right mount.  Barry (ATL) is hard into these, and we expect delivery in about six weeks.  (Picture attached)

Michelin Air tires
I retrieved out of my storage container two brand new Michelin 32 x 8.8 main aircraft tires that I had bought years ago.  They are still in perfect condition as they were kept dry and not exposed to any UV rays.  Today’s value of these tires is $903 each.    By the way, they fit our XP-82! (Picture attached)

I am also continuing to contribute bearings, rivets, hardware and other misc. supplies out of my Kissimmee stock to the XP project.

With the stock market being so uncertain lately, we have had a number of our investors increase their shares these past months.  Thank you, every one.  We had a few other very nice, acceptable pilots and businessmen also make inquiries this past month.  

Rear fuselage forward attach angles
Being a stickler on having certification papers on every last part, rivet, etc., I called to order the internal wrenching 7/16” (.437) M.S. (military standard) bolts to attach the verticals to the lower aft fuselages.  Fourteen in all are required.  None of the hardware suppliers I called had any in stock anywhere in the country.  My price would have been 106 dollars each!  So as a last resort, I called my surplus hardware dealer and he had them in the original military boxes for the astronomical price of one dollar each.  What a deal!!

Welcome to the Group
A pilot and businessman that I met in Lumberton, NC, last month has come on board and joined our group.


Our new mill
Weather
Summer in Georgia sure came on with a vengeance as the daily temps in the hangar are over 100 degrees F each day.  We have lots of fans running so we are not losing much efficiency.  The temperature in our #1 container with the water spray on the roof and walls maintains a very comfortable 80-85 degrees.

The Katz
Our inseparable Katz
They are inseparable.  When Rivet went to the vet to get fixed, Allison was beside herself looking for her for two days.

Bumps in the Road
One small one.  We had to make the four engine mount side skins, each being 6” x 48” by .063 over again due to making them out of 2024 T-3 instead of 7075 T-6.  The XP-82 side skins appeared to be imprinted with 24ST, but all of the later production models were 7075 T-6.  Not bad--one half sheet of aluminum and one day drilling.  Since the beginning, I don’t think we have lost a total of two sheets of aluminum out of over 150 due to mistakes.

Question
We have had a number of investors express an interest in having a XP-82 party in the hangar later on this fall when the temps come down.  I have kept everyone’s identity and investment amount private.  A party could be an opportunity for every investor to meet one another.   Let us know if you are interested, and if you are, we all will pick a convenient date.


Come see your aircraft!    Happy Fourth of July!!





Thankx

Tom

No comments:

Post a Comment