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-   -   Andair Fuel Pump installation problems (https://vansairforce.net/community/showthread.php?t=57644)

RV7Factory 05-12-2010 02:52 PM

Bruce, thanks for your very kind words. :o

2009 was chaos for me, and I didn't get much done on the RV, but I am trying to get my butt in gear in 2010.

I've got a few ideas on how I will accomplish this. First, as you said, is to remove about 3/8" of material from the vertical component of the angle in the shape of an arch. This would give me roughly 9/16" clerance below it, which I am not sure is enough in the long run.

The other option is to replicate what you did by installing a doubler, but also tying it in to the vertical sides of the cover (perhaps by using some .063 angle). I've got a picture in mind and it shouldn't be hard to do.

BSwayze 05-12-2010 06:15 PM

Quote:

Originally Posted by RV7Factory (Post 432262)
I've got a few ideas on how I will accomplish this. First, as you said, is to remove about 3/8" of material from the vertical component of the angle in the shape of an arch. This would give me roughly 9/16" clerance below it, which I am not sure is enough in the long run.

The other option is to replicate what you did by installing a doubler, but also tying it in to the vertical sides of the cover (perhaps by using some .063 angle). I've got a picture in mind and it shouldn't be hard to do.

Brad, yes, that's exactly what I was thinking of doing at first. Cutting an arch in the angle, that is. In my case, I have installed some 1/4" soundproofing material to the floor, though, which limits the clearance even more. I'm considering another layer of the material applied to the underneath side of the cover, to create a "sandwich" of the material through which all the lines will pass. This will provide even better sound insulation as well as cushion all the lines from any vibration. So the angles just aren't good for me.

I see what you're saying about the .063 angle stock to tie the stiffener in to the side angles. I think it's all unnecessary overkill, though. Just my opinion. What may be another problem is that the angle built into your cover has a curved radius in it. The square corner of the .063 angle won't nest in it so you're in for some work to put a radius in the material. Then how strong would it be? Or you could use .032 angle so the radius is the same. If you want to overlap the stiffener plate and rivet it together, though, you'll also have to put a joggle in either the plate or the flange on the angle where it overlaps. It's all doable stuff if you have the tools and want to put in the time. I think you'll find, though, that it just isn't necessary.

If you could see how stiff and strong this assembly of mine is now, you would probably think so, too. Remember, the steel pump bracket adds even more strength The stiffener I made is large enough that it goes almost all the way over to the new angle on each side. I'm very pleased with it. The only thing I debated was whether to use .040 or .063 sheet for the stiffener. I ended up going with .040 since I had some on hand in my trim bundle. Plus, it won't be that hard to replace if I ever needed to beef it up. But I can't imagine that will ever be necessary. Time will tell.

Let us know what you finally decide to do.

RV7Factory 05-17-2010 11:19 AM

Just a quick follow-up with my research. Perhaps I am over-thinking this, but allow me to have my fun. :)

Here are the two options I mentioned. The first would be where I trim the angles, and the second is the use of a doubler and some angle along the edges for added stiffness.



By trimming the angles, I would end up with a space between the cover and the belly skin of approximately 5-3/4" x 3/4" (the block of wood is a 15/16" spacer I fabricted to set the cover height). It's probably adequate, but since I don't know what avionics I'll be using or how my electrical system will shake out yet, I am not sure if it's enough in the long run. You also have to consider that the pump mounting hardware will also penetrate this space.



The second option is to install a doubler (of .040 or .063) and use some .063 angle along the sides to stiffen it all up. This would leave almost the entire space under the cover available for use. The picture is just an example using some scrap, but I think you'll get it.

My vote, and the direction I am headed... Option #2.

BSwayze 05-18-2010 12:21 AM

I'm for #2
 
Brad,

Yes, I think you have a couple of workable plans here. I'm for #2, though, like you're thinking. Funny, the .063 angle stock I have seen has a square corner. Yours has a curved radius corner. So it would work much better than what I was thinking.

I still think the added angle is unnecessary, considering that the floor stiffener angle will stiffen the cover as it's bolted to it. So it acts as the stiffener you need. An additional one is redundant, as I see it. Not to criticize your approach, however. At all. Just my 2 cents worth. You're always better off having something too strong than to err the other direction. And your own comfort level matters the most.

If you do go with option #2, don't toss those angles you made just yet. Mine came in very handy to help me make and fit the forward fuel line. Using them, you can temporarily install the pump and its bracket using those angles, while leaving the cover off, so you have access and can see what you're doing. I described how it worked for me here:

Log Entry May 14th

Here's a picture:



I'm anxious to see what you end up with. Good luck!

RV7Factory 05-18-2010 12:34 AM

Quote:

Originally Posted by BSwayze (Post 433666)
Funny, the .063 angle stock I have seen has a square corner. Yours has a curved radius corner.

That's cuz I put it there... the radiused corner that is. :)

Quote:

Originally Posted by BSwayze (Post 433666)
I still think the added angle is unnecessary, considering that the floor stiffener angle will stiffen the cover as it's bolted to it. So it acts as the stiffener you need.

You're probably right, but I'm going to take the belt and suspenders approach with the fuel pump. The one thing that concerns me (even with a doubler installed), is the stress put on the bent corners of the cover over time. By doing what I am going to do, the angles will really beef up that area and prevent ANY vibration. Like you said, whatever gives me the warm fuzzies right. ;)

PS - Nice tubing bends!

erich weaver 05-18-2010 09:46 AM

You guys are way too far along for this to be useful, but for others reading, take note: Due to a past manufacturing error, many oversized cover pieces were shipped by Vans that were a shade to wide to fit properly between the floor stiffeners. I suspect many of us (me anyway) cussed at it, jammed it in there, and made it work with everything kind of tweaked. Somebody on this list finally bitched to Vans and they eventually fessed up, fixed the problem and sent replacement parts for the asking. If yours is too tight, you likely have this problem.

erich

BSwayze 05-18-2010 03:39 PM

Quote:

Originally Posted by erich weaver (Post 433775)
You guys are way too far along for this to be useful, but for others reading, take note: Due to a past manufacturing error, many oversized cover pieces were shipped by Vans that were a shade to wide to fit properly between the floor stiffeners. I suspect many of us (me anyway) cussed at it, jammed it in there, and made it work with everything kind of tweaked. Somebody on this list finally bitched to Vans and they eventually fessed up, fixed the problem and sent replacement parts for the asking. If yours is too tight, you likely have this problem.
erich

Wow, Erich,

Thanks for the info on this, even though it is way too late for me. I didn't know that! Mine's all fixed now and I'm finally happy, but I'm sure the cover was the problem in my case, it was so bad. I considered getting a new one, but thought it would be the same so what would be the point. I wish I had known. A new cover would have been nice. On the other hand, all the work that goes into that part is an big investment of your time, the bending of the louvers and all the tedious deburring followed by all the prep work, priming, riveting, painting, etc. It would have probably taken more time than the fix I engineered. So in the end, all's well that ends well. At least I don't feel so bad now thinking I installed the floor stiffeners "too close together". I went back and reviewed my pictures of how I installed them, and it was right on, by the book.

Hopefully this will help another builder. Thanks again!

erich weaver 05-18-2010 04:22 PM

well, at least you have some company in this regard huh?

The fit of the defective part was close enough to make you (and Vans) think its gotta be your own fault, but in this instance, that was not the case

regards

erich

bruceh 11-08-2010 06:27 PM

I'm contemplating getting my fuel system figured out and am considering the Andair Pump & Filter (already have their Valve).

My question is how can you access underneath the center tunnel once the pump is plumbed? It looks like with the access hole cut in the middle for snaking the fuel line that there is no way to take the tunnel cover off for wiring, etc. Is the lack of future access a problem, or do you just need to undo the fuel line if you need to get under there?

Looking at Van's Airflow Performance Fuel Pump set up, there is a separate aft tunnel cover and mounting bracket. It would be nice to have the Andair pump mounting be separate from the rest of the tunnel cover.

What are the options here? Cut the tunnel cover in two and fab up my own parts? Does Van's sell an AFP bracket without the various bends/cuts for mounting stuff? Leave it in one piece and put down some wiring conduit?

BTW: my tunnel cover also suffers from being just a bit too wide.

RhodeIsland9 11-19-2010 07:02 PM

cut the panel in half
 
I cut the original panel in two pieces and installed a .040 doubler and some .032 angle. The doubler was left long to fit under the front cover half and the fwd screw of the fuel pump cover fits into a nut plate in the doubler.




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