Sunday, November 25, 2018

Section 28

I am finished with section 27 which is the Firewall section.  There are still a few things to do such as the heater boxes need to be bolted on but I'm still thinking I might buy some stainless steel boxes to replace the aluminum version's that Vans includes in the kit.  Still not sure on that one but in any case its just a quick bolt on.

I jumped ahead a bit to the brakes section.  The plans tell you that its ok to jump ahead and do the brake lines that run down the tunnel at this time so I went ahead and started that process.  It reminded me of why I went with braided lines for the 9A...bending tubing is a bit of a bugger!  I got one side done but will likely redo it as I'm not 100% happy with the way it turned out.

Lastly I got my sump back from Divco last week.  I primed it this weekend and I now have everything I need to assemble the engine.  My only hold back is that once its assembled its going to be pretty darn big and I'm running out of room to store stuff! 

In my office I have a huge box with windows, the overhead console and the center console as well as a few odds and ends.  In the work area of the garage I have the instrument panel, the various pieces of the fuselage, and who knows what else...its getting tight!

Oh yea, I forgot that I had drilled the cotter pin holes in the two wheel pant standoffs that I turned last week...I had to buy a centering jig and then find a way to "clamp" it to the standoff.  A hose-clamp worked out nicely.

Right down the center of the hole!

Lots of RV-10 parts sitting in my office waiting their chance to get installed. 

Firewall all cleco'd together with Firebarrier 2000+ (the grey stuff) to prevent any carbon monoxide gases from getting into the cabin.

Same thing, other side.

New parking brake mount installed. (the black part on the left side of the photo.  This is the part I created with my CNC.
Here is the parking brake valve installed and the left side brake line attached.  I still need one more fitting for the right side brake line and that should arrive later this week from Aircraft Spruce.

Wednesday, November 21, 2018

Another modification - Wheel pant extensions

One of the commonly known failure points on the RV-10 is the extension that attaches the main wheel pants to the axle nut. Being the creative group that airplane builders are it didn't take long for a few options to appear including this one.  Some of these solutions are available commercially such as this kit from Cleveland tools which lists for $50.

I'm a long ways away from needing these but since I have Ben's lathe set up I decided to take advantage of it and turn my own.  I spent $6 for the aluminum, and 6 hours of airplane time, to make my own version.  Was it worth it?  No doubt, not in the money saved ($44) but in what I learned about metal work and also the satisfaction of having made my own parts.  There is still a bit of work left to be done on these (tapping the bolt holes for example) but overall I'm happy with how they turned out.  I love these modifications!

Here they are.  Two nicely turned extensions with a huge pile of aluminum shavings in the background.

Sunday, November 18, 2018

Special Mods

I really look forward to working on the fuselage for a couple of reasons.  First its simply because the fuselage is "where the people go".  It also, and probably because of the first reason, is an area where I plan to do most of my modifications to the airplane.  This week was a week (actually 2) of modification.

On the firewall I plan on mounting a parking brake.  This requires a mount of some sort and there happens to be a bracket that gets riveted to the upper left side of the firewall that is designed to connect the brake lines with the lines coming from the pedals.  This seemed like a good place to mount my parking brake and there happens to be a company (Airward) that makes a "kit" that allows you to do exactly this.  I like this company's products but I don't care much for the prices....or at least thats what I thought at first.  For $197 they will send you everything you need to mount the parking brake valves in the required location.  Being the cheapskate that I am I decided I would just use my CNC and make my own kit for about a quarter of the price.  Sounds logical doesn't it?  Well, having spent about 10 hours of my time coming up with a similar "kit" I am starting to see a lot of value in that $197.  :-)  None the less I did manage to get the parts I needed and am ready to move forward on that project.

F-6122-1 is the bracket that I will be replacing with a parking brake mount.

This is my CNC noisily cutting away at the square bar that I purchased to make the bracket replacement.

Another view of the CNC cutting away.  This is a huge mess to clean up by the way.

Anyway after many hours this is what I ended up with.  It doesn't look like much now but soon it will have a parking brake valve bolted to it and it will be riveted in place of that F-6122-1 bracket you saw in the plans above.

Next up on the modification list is a tunnel access plate.  The electric fuel pumps are located in the center tunnel.  Working on those pumps and associated fuel lines and power leads requires you to work from above with very limited space.  The company I mentioned above (Airward) makes a "kit" that you can purchase and install in the side of the tunnel to give you a nice open way to access the tunnel components.  Unfortunately the kit they make is not the size I needed so so once again I took to the CNC and made my own access panel and backing plate.  This was much easier than the bracket above but it did take about 8 hours total to design, cut, and install the access panel.  As of this time it is not riveted in place but its ready.

This is the tunnel side wall.  The pen marks are the size of the access cover that I will be installing.

And after many hours of cutting, deburring, drilling, dimpling and even a little riveting this is where we stand tonight.  

Finally I have one more customization that I completed today.  My good friend Ben let me borrow his lathe again so that I could turn a couple of inserts that will go inside the step support tubes.  The RV-10 has a problem where the bolt used to fasten the step support tube in place has a tendency to loosen due to the bolt collapsing the thin tubing. There is another company that makes an insert that prevents the tube from collapsing.  Well since Ben has a lathe I decided to spend $8 on a piece of aluminum and turn it myself.  This wasn't a long project but it sure is a satisfying one.

HAH, this picture makes it look like the bar is all white but as you can see below its actually just simple 6061 aluminum.  The spinning motion must have given it the white appearance.

Here is the aluminum stock turned down to the proper size.  The grooves you see are where I will be cutting these "blocks" off of the bar with my band saw.

A bigger picture of the entire lathe and bar set up.

After turning the bar I used my dowl centering jig (the blurry thing sitting on the bench to the right of the picture) to drill these holes into the exact center of the blocks.  Once these holes are drilled I simply cut the blocks off of the bar using my band saw.

And finally the blocks get slid down into the step tube after the bolt holes are drilled.  You can see how these new blocks prevent the collapse of the thin aluminum tube when bolts are tightened.  

Sunday, November 4, 2018

Starting the firewall

Travis came over this weekend to help me finish riveting the mid fuselage floor skin to the bulkheads.  It was nice having him over again to help with the riveting.  He, and many others helped a lot on the 9 when I was building it but the 10 has been a little different in that I have found ways to do most of the riveting solo. 

I started on the Firewall this weekend and I will say that it seems to be much easier than the 9 firewall.  Maybe its just experience but it seems to go together much easier and there are fewer self manufactured parts in this firewall.  More detail in the pictures below.

I have a few modifications to make to this next section of the plans.  First I had to drill another hole in the firewall for a return fuel line.  I plan on having either a EFI fuel return of at least a purge valve to help with hot starts.  Next I am cutting access panels into the side of the tunnel so I have better access to the fuel pumps and related fuel system components.  That requires a backing plate and a cover plate so I designed a pair and then started the cutting process this weekend (on the CNC).  So far I've made two covers but no backing plates.  There are a couple of changes that I still don't know about yet that will have to have a modification made to the firewall.  First I don't plan on using Van's method of oil cooler mount.  It basically bounces the air flow off of the firewall and then back into the oil cooler.  I think I can come up with a little better system than that.  Second, I plan on using stainless steel eyeball type control cable penetrations and the three small holes that Van's put in the firewall for this purpose are too close together for the 1" eyeball.  So a little work will be required there.

This is the mid fuselage section that Travis and I riveted the floor skins to.  Notice the bubble wrap?  Well those two bulkhead frames kept poking me in the face...

Oh yea, another modification that required some custom work.  This is the fuel selector mounting plate.  The Andair duplex valve that I purchased is different than the one Van's supplies in the kit.  So I had to modify the mounting plate to fit the new valve.  You can see the part that I cut out (blue) and the new section riveted to the side flanges.

Here are some measurements for the access plate that I am putting into the tunnel walls.

And here is the CNC happily cutting away on the first cover plate.
And finally, after several hours of deburring both the aluminum parts as well as the stainless steel firewall parts I was able to fully cleco the firewall together.  Next up is the round of final drilling the holes before disassembly.   See those steel plates on the bottom of the firewall that look like shovel heads?  Well those are not on the 9A firewall.  On the 9 I had to fabricate some beefy aluminum angle and I remember that giving me all kinds of fits.  In fact I had to drill them both out and "bend" the flanges to get everything to line up during final assembly.