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Tip: EZ removal of firewall mount battery

Rick_A

Well Known Member
I’ve always struggled with getting my PC680 battery out of the firewall mounted battery box. There is no place to get a hold of the battery and I just barely have enough room to lift the battery straight up (because of other things mounted above the battery).

I made a simple battery lift strap and it worked like a charm. I used a couple of small L-brackets that I covered with heat shrink/electrical tape. I drilled a hole in each leg of the bracket. I than screwed one leg of each bracket down using the screws that attach the electrical connections. I ran some 1/4 rope that I had laying around though the upright leg of each bracket.

The old battery lifted right out - easy peasy. Then it was just the usual maneuvering the battery to clear the engine mount.

I can’t believe that it took me 13 years of working on the plane to figure this one out. :)

P.S. I actually didn’t even have to make the brackets. I found a couple of pieces of bent scrap metal with holes already drilled to the right size.
 
I used some bulk nylon strap material (7/8" wide IIRC), folded the ends, burned a holes with a hot nail. I just could not get my battery out so made this completely non-conductive tool. It is light, strong and travels well in the tool kit.
 
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Van's battery box..... I just reach under the box and push the battery up till I can grab it. PC680.
 
I like it

I used some bulk nylon strap material (7/8' wide IIRC), folded the ends, burned a holes with a hot nail. I just could not get my battery out so made this completely non-conductive tool. It is light, strong and travels well in the tool kit.

I like this idea better than the way I did.
 
Just replaced mine after about 7 years as it was getting tired, same PIA to get it out, finally tied some cord around the post bolts and lifted it out and used same procedure to lower new one into the box. Simple and cheap. I followed Dan when building my -7 but missed the battery box hinge idea, simple but brilliant :D
Figs
 
For simple and compact, i just take a strip of gorilla tape and stick it to the side of the battery so that it sticks up an inch more or less above the battery. double it over so that it sticks to itself. now you have a tab sticking up that you can tuck into the battery box. use fingers or pliers to lift the battery. fabrication time: 15 seconds. cost: 15 cents
 
Which one?

anyone know the mounting hole pattern of this pc680 bracket ?
dimensions

The aft mount trays, the steel box from Odyssey (via Vans), or the FW mount used with the 14? The 14'ers were nice enough to share their plans for FW mount. I need weight forward. It was one of the easier "incorporations" into my build. Added bonus = Battery can be lifted up or forward for removal. No additional improvisation for battery removal is needed (hopefully).
 

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They were prepunched. IIRC, the top line of 6 @AD4s go through the FW cross support angle per design. One of the lower corners incorporated a small stiffener on the aft side of the FW . The remaining sides were through the FW sheet only @24 total #4s.

I was additionally able to pick up one each rudder hangar support. Both top and one side have some modified spacing but it’s at least as securely fastened as 14.
 
Am making my own bracket, so, if there is a standard hole pattern,
distance between holes, etc, I'd like to know it per the prepunched bracket.
 
Am making my own bracket, so, if there is a standard hole pattern,
distance between holes, etc, I'd like to know it per the prepunched bracket.

None of the structural guys answered so here goes. There are too many variables/unknowns to answer your question correctly. Some conservative assumptions can be made but they are only that. Vans engineering determined the number of #4 rivets needed to support the shear load of that battery at the conditions/category of the 14. It's an easy back calc from the load to determine -> the area needed in shear (based on known properties of AD rivet material and geometry) to support such -> # of rivets required. The battery has a fairly even weight distribution with a center of mass near the geometric center; so, you could easily assume that evenly spacing the same number of rivet around the periphery of whatever frame you're making would be a safe application. This also assumes the EDs and spacing did not exceed minimums which they don't. All of these assumptions are for the #, SIZE, and TYPE OF RIVETS ONLY. I personally would be more concerned about the support from the FW and the battery "bracket" you're proposing. That's all that can really be answered with the details you've provided.
 
ok, thanks for answering..
I assumed there was a " standard " hole ( .25") size and layout ( 2" apart )
so, that a new bracket could replace an old bracket, without drilling new holes.
I will show picture of it soon.
 
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