Final fitting the fuel pump cover - 2 hours

Managed another quick build session tonight. I need to complete the sides of the fuel pump cover. I clamped the assembly to the table and then began marking and drilling the remaining rivet holes. The top of the cover needs to be parallel with the bottom of the flange. The forward end of the cover is basically set...as long as the front is vertical. The assembly is clamped into place and I can then start drilling rivet holes.

Once that was done, I can then trim down the sides to fit the top of the cover. All I need to do now is final fitting and drill to the center tunnel cover. This is easy to do as I still have all of my reference lines in place. I started from the rear and moved forward. Drilling all holes, 3/32" first, 1/8" and then #19 last. 

More fuel pump cover fabrication - 3.5 hours

 With the top cover position established. I now can figure out how I want the cover to fit over the pump and where I want the cover to end. I measured and marked out all of the bend points, cut relieve notches and then made all of the bends.  A simple description but it was more tedious then that, I just don't want to mess this up. By the end of it, I was really happy with how the top cover was sitting and now I just need to start fitting the side covers.

I clamped them on, and started using a level to get things straight but soon found that a level is not going to work correctly as the centre tunnel is angled slightly and I want the cover to sit parallel with the pump. I'll stop here and come back to it when I can think it over a bit more.

Fabricating the fuel pump top cover - 2 hours

 Today I need to fabricate the top cover of the fuel pump doghouse. This will basically be a c-channel shape that I will eventually shape into the final cover. To make the initial cutout. I took some measurements of the original stock cover and worked my way from there. I cut a long rectangle out of 0.020" material and then started marking out my flanges. 

The first 90deg bend is fairly straight forward. Once the flange length is set, clamp the oak bending guide, start the bend by hand, and then finish with the rubber mallet. 

 

The next part is trickier. Get the other bend the right distance apart. This is where having the stock cover is super helpful as I can use it as an exact guide. After the opposite flange is bent...I checked it against the stock cover. I'm very happy with it.

Now I am ready to make the flange bend at the aft most end of the cover. Same process....

 

With that done...I am now able to place the cover on top of the fuel pump and establish the final height of the cover. I placed spacers on the top of the pump, placed the cover on, centered it and them drilled with 3/32" holes.

Started the custom fuel pump cover - 2.5 hours

 With the FlyEFII fuel pump and the Aerolab Gascolator I just won't be able to fit everything under the stock doghouse cover. I will need to make my own custom cover. I order to do this, I'll use the stock cover that I have as a guide and make a longer (shallower) version. 

 

I cut the forward fuel access hole out in the reinforcing plate yesterday. I can now get clamps in to hold everything in the right spot. I could then start sketching out all of the lines to determine the rough dimensions of the cover. 

First, I need to make the sides of the fuel pump cover. I choose to use the same 0.020" material as the stock cover. I basically need to cut out a long rectangle and bend one edge with a 90deg flange. 

I clamped the piece to a table and then using a piece of oak with a 1/8" radius, I began the 90 degree bend for the flange. The initial bend is done by hand, with the final process being a rubber mallet. I made both the left and right side covers this way.

 

 

 

Reinforcing the fuel pump platform - 7 hours

 Immediately it becomes apparent that the F-782C tunnel cover is not going to support the fuel pump adequately.

So I will need to reinforce the mounting to allow a more sturdy installation. Since the fuel lines are all hard lines, any excessive movement is sure to invite leaks. I began to think about how I was going to do this, lots of builders have tried various methods. I settled on keeping it easy. My plan is to support the platform with 0.063" baseplate and use 3/4"x3/4x0.063"angle. Here is a mock up to help me sort out the fit and dimensions.

 I started out by cutting the 0.063" plate to the correct size. Then I used a file and slowly worked a radius edge on the plate.

  Next, I rounded the angles with a router and a 1/8" radius bit. This makes for a really great fit with the tunnel cover.

With that done. The pieces are now ready to be fitted and drilled to the center tunnel cover. 

Preliminary installaiton of control sticks and mock-up - 3 hours

 Not feeling that I want to get too in-depth on the build today, I decided to mock-up/fit the front panel area. I've fit the pieces before and things seem very tight with the F-7105 sub-panels. Everything else is spot on so I think it will be just a matter of tightening up the radius of the mounting flanges. Easy enough to do, just a matter of working at it.  As well I like pulling the project out on the driveway when the weather is good like it has been, and it looks great with the front panel on. 

I'm at a point where I can install the control stick assembly. This part can be a little tricky from other build logs and sure enough getting the WD-610 control column slipped into position isn't the easiest, however it wasn't horrible.  What is horrible is getting the AN960-10 washers fitted on the control column mounts. That is horrible and not easy to do. Using a combination of a small film of grease to get the stack of washers to stick together and some safety wire bent to hold the washers...I could get them slipped into position. 

 

For now I just temporary installed the left and right control sticks and the F-665 pushrod for looks, but I will need to remove those and finish those items properly at a later date (Prime the pushrod, drill the safety bolt in the right stick, torque everything).

Modifying the center tunnel for the fuel pump - 6 hours

Time to get to work on opening up the center tunnel for the fuel line that exits the fuel pump. I started out by drawing all sorts of reference lines.

 

Now that I have the hole for the fuel line decided, I also have the line where I want to split the center tunnel into two. This will allow the fuel pump to remain in place if I ever need to get into the forward portion of the center tunnel. I need to drill the mounting screw holes accordingly.

The first cut dividing the tunnel cover in two is made.

I am now able to cut the opening for the fuel line.

 

Completed the right fuel vent line - 4 hours

 Well a decent day of building hours wise. but not a whole lot of forward progress to show for it. I managed to complete the right fuel vent line. Took me a couple tries for the right side still. Having all of the sample bends and the left fuel vent line done is a great template for getting the right side done. 

Here is the left side for comparison.

Completed the left fuel vent line - 3 hours

Well it took some work but I managed to complete the left fuel vent line. I was able to use all of the templates that I made previously as a guide. 

Even more fuel vent work - 6 hours

 Following the same method as before. I want to use smaller lengths of tubing to find the recipe and provide a template for the rest of the bends. It took some time to get it all worked out, but I'm pleased with the results. I will now be able to use these to make the permanent fuel vent.

More fuel vent work - 1 hour

 Just a small day today on the fuel lines. I used a long section of tubing and started the bends on my actual fuel vent line. Managed to get all of the initial bends right and was able to attached the vent line to the bulkhead with the adel clamps.

Began the fuel vent install - 6 hours

 This is a part of the build that I was never really looking forward to. From what I've been reading this isn't the most simple and straight forward process. Then again, what did I expect....were building an AIRPLANE!

I have been looking at the option of F1 rocket style fuel vents that are coiled tubing contained within the wing root. Lots seem to report they work well. However I met an F1 Rocket owner and he didn't seem all that enthused about how they perform when I asked him about them. I ultimately decided to face the tricky tube bending head on. 

1/4" tubing is way more easy to work with and tweek versus the 3/8" tubing. So straight off I knew this would be less challenging then I thought. I decided that I will work the tubes from aft forward. Starting with the most difficult bends first and then leave the most simple and straight forward bends at the end.

Rather than eat up long lengths of tube, I choose to fabricate each bend making a template out of small sections of tube. This would allow me to "stitch" together a complete fuel vent with a precise example to follow.  I should note that all bends are been done with a tube bending tool, and only slight tweeks are being performed by hand. I also use a 1/4" tubing straighter to get all the coiled tubes straight before I start the bends. Both tools are fantastic and easy to use.

The first challenge is to sort the first section which turns out to be the most complicated portion of the vent. My first attempt clearly shows that I have distance issues between the 90deg fitting and the side stiffener angle.

The tube makes contact with the angle. So to solve this...I need to shorten the distance between the flair and the bend. Learning from previous samples I have shaved down the AN fitting sleeve. The result is that I can move the sleeve out of the way and get a much tighter distance between flair and bend. 

The result is excellent. Great spacing to go up and over that angle.

That solved, the next hurdle is to get the tube bent under the rudder cable. Simple enough... Using a piece of hinge pin strung through the rudder cable holes and attached to the rudder pedal with tape, I can easily see clearances.

At this point things look really good, but now I need to get this tube to offset enough so that it sits closer to the F-902 bulkhead and can attach with an adel clamp. That part of the bend is a pain. With my current setup, getting that offset bend is difficult and takes up a lot of space. It also looks awful. So, the way to fix that is to start my offset bends further down as the tube slips under the rudder cable. The result, while still tricky is a much more clean bend.

This is the exact 'recipe' for this section of bends (Keep in mind, that these work with my particular brands of tools);

1. Start the tube by bending 45deg a couple of inches from the end.

2. Flip the tube 180deg and then bend the tube 90deg immediately.

3. Measure 1" (Measured from the end of the previous bend to the start of the next bend).

4. Make a 45deg bend. (At this point you are now slipped under the rudder cable and the tube is pointing straight up from the fuel vent fitting).

5. Rotate the assembly 45deg in the tubing bender and bend the tube 60deg. (This now angles the tubing toward the bulkhead).

6. Measure 1" and then bend 60deg. (At this point the tubing should now be straight up to follow the F-902 bulkhead as shown in the picture above.)

7. At the end you have started on. The tubing can be cut and flaired. The exact length is 3/4” from end of the bend to the end of the tube.

8. Some slight tweeks will be required to get it all straight and aligned.