Saturday, January 19, 2019

More tailcone stiffener drilling

 Started today by adding the right hand stiffeners to the assembly

 Then the right skin.  Cleco'ed the right side skin to the bulkheads and the bottom skin.

 Drilled all the stiffeners to the skins per the directions.  Simple....just align the marks on the stiffener with the holes and drill.  It takes some arm gymnastics to keep the lines centered in the holes.  Just go slow and carefully and keep the lines centered.

 Right side stiffeners all drilled.

I flipped the whole tail cone over on the horses.  Then I cleco'ed the back two bulkheads and the bottom aft skin to the assembly.  It is amazing how tight all these parts are.  At first it seems impossible but the more cleco's that go in, the better things start to align.  It is a testimony to Van's engineering department!  I remember similar pain and agony getting all this stuff in this area to align when I built the RV-7.

 The aft two bulkheads all cleco'ed to the assembly

 Next I added the stiffeners to the left side.

 And then cleco'ed the skin to the bulkheads and the bottom skin.  Also the aft two bulkheads and aft bottom skin.  Had to use a sharp scratch awl to align some of the holes.

Starting to look like airplane parts around here!

Thursday, January 17, 2019

Tail cone bottom stiffener and bulkhead drilling

 Started tonight by adding the vertical extension to my new saw horses.  This gets them up high enough to clear all the bulkheads.  Easy peasy.

 Then I cleco'ed the aft three bulkheads to the bottom skin.  This is a bit challenging to align.

 Then I slid the two fwd stiffeners into place.

 Then I aligned the centerline with the holes and aligned the starting point to the fwd most hole and drilled the stiffeners to the skin with my new 4000rpm drill.  Man I love this thing!  Makes fast work of these holes!

 Here are the fwd end of the fwd stiffeners all drilled.

 And then I drilled the aft end of the fwd stiffeners to the skin.  Go carefully and make sure the line stays in the middle of the holes!

 Then I slid in the aft center stiffener and drilled it the same way.

 Then I cleco'ed these two bellcrank ribs to the assembly.

 And match reamed their holes that are common with the skin.  I could not find anywhere in the directions on when to do this so I did it now.

 Then I match drilled these bellcrank rib flange to bulkhead web rivet holes to #30.  Used a 12" drill bit to make it easier to align.

Here are the stiffeners and bellcrank ribs all drilled to the bottom skin.  I love the new drill!

Tuesday, January 15, 2019

Tail Cone, saw horses and stiffener marking

 Tonight I had to go invest in some adjustable saw horses for assembly of the tail cone.  I will have to add a plank to the top of them to get them high enough while the assembly is upside down.  This is so the largest bulkhead will clear the ground.  I am just going to screw a 2x8 edgewise to the top of them to solve the issue.

 Next I marked the centerline on the J stiffeners along the long edge.  I bought this compass thing at Lowes for $5, added two zip ties and a sharpie pen and walla, instant adjustable edge marking tool supreme!   Doing the marking this way prevents the bow in the stiffener from screwing up the centerline.

Works slick as a ribbon!

Monday, January 14, 2019

Tail Cone Longeron Work

Back to work on the plane!  Been sick and out of town for a couple weeks!  Tonight I got started by marking the longerons for cut to length.  They are shipped a little long.  Measure about 10 times on this one because you don't want to screw this up!

I used the cut-off wheel for this job.  To long and wild for the band saw.

Then I marked the HS stab mount bar relief holes and punched them for drilling.

Started with a smaller drill.

Then went up to 1/4".

Next I marked for the relief cut.

And used the cut-off wheel to cut out the material.  Then used a few files to clean it all up.

Next comes the whack a mole method to bend the longerons 2° down at just the right spot.  I just followed the directions and it works.  Seems brutal and it is but it works.  Did the same thing back when I built the RV-7.

Here you can see the slight angle starting at that line when compared to a straight edge.

And once the second one is done, here are the two back to back.

Monday, January 7, 2019

Been sick....Got new tool!

Been sick as a dog for over a week!  Very little getting done on the plane....

So I built an entire RV7 with a cheap, slow and noisy Harbor Freight pneumatic drill motor.  I decided I had had enough of that and bought this Nova 4000 rpm motor!   This thing feels like a very quality tool.  It is very lightweight, compact, and feels great in your hand.  Half the price of its nearest competitor.

While the new drill motor is only 1/4” capacity, it is much more compact vs the old motor.  The Nova has a feathering trigger/throttle which is awesome!  The old one is basically on/off.

The old motor weighs 2 lbs 8.6 oz.

The Nova is almost a pound lighter at 1lb 9.8 oz.

I tested the speed of the old motor and it came in at 1475 rpm.  The Nova turns 4058 rpm!  The higher rpm is better for small holes in aluminum.  The high speed helps minimize the pressure required and gives you a rounder hole.  The high speed is an advantage on drilling thick stock like the million holes in the longerons.

The old motor is very loud,  the Nova is almost as quite as my battery powered drill!  
I did a test with a dB meter 1’ away from the motors.  The old motor averaged 100dB while the Nova averaged only 78dB!  


Saturday, December 29, 2018

Tail Cone Bulkhead and Stringer Work

 So my wife bought me this time saving tool for my birthday.  Definitely a luxury tool!  I tried it out on a few holes and it seems to work as advertised.   May have to get a #30 sized one as well.  Basically this lets you deburr both sides of a hole with one quick motion.  Works also for blind holes and holes where you can't get normal deburr tools to the backside of a hole like close rib flanges and stuff.

 Started today by fabricating this stiffener that goes on top of one of the bulkheads.  The ends are to be cut at an angle.

 The bandsaw made this easy.  Just used a piece of wood to hold the aluminum angle up as required for the cut.

 Next was separating these doublers.  I think these were added to the kits as a SB at some point because this bulkhead was cracking.

 Used the bandsaw to separate them, then deburred them.

 Now I marked center and the 1/8" line on the aluminum angle I cut above.

 And clamped it to the top of the bulkhead after clecoing the doublers on.  I used the center line and the 1/8" offset line to center and properly position the angle.

 Then I match drilled the angle to the bulkhead.

 Next I cleco'ed this bulkhead together.

 And match reamed the common holes.

 The next bulkhead got the same.

 And match reaming.

 And punching up these holes to 5/8" with the unibit.

 Then the largest bulkhead.

 Only the top cross part gets match reamed at this point.  The bottom ones don't get done at this point.

 Finally I cut all the J stringer's to length.

And cut the ends at the 45° angle per the directions.