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Fuel tank Z brackets: there ain't no "Checkoway method"

dan

Well Known Member
I keep seeing the "Checkoway method" mentioned in numerous threads when it comes to fuel tank Z brackets. I really want to put this to bed.

There ain't no Checkoway method. I didn't come up with anything. All the credit goes to Steve Hurlbut -- who posted it about 12 years ago. This is where I came upon it originally:

http://www.matronics.com/searching/...TNUMBER=138?SERIAL=1948382694?SHOWBUTTONS=YES

And in case that link goes by the wayside like some builders' websites have (ahem):

Message: #90620
From: "Steve Hurlbut" <hurlbut_steve(at)hotmail.com>
Subject: Perfect Fuel Tank Alignment
Date: Dec 16, 2001

I just finished my left wing fuel tank (not sealed yet) and the aligment with the leading edge is perfect. The problem with Van's instructions is they tell you to drill 1/8" holes and #12 holes in the fuel tank attachment brackets which will decide your alignment before you even get the tank on the spar. Here is what I did:

1.) Drilled 1/8" hole in exact centre on one side of attachment bracket. Make 6 of these. No #12 holes! Cleco brackets in place and drill remaining 4 holes ensuring it is centred.
2.) Put fuel tank skin in wooden cradle and cleco ribs in on one side only.
3.) Put baffle in place. With attachment brackets removed.
4.) Lift up free side of fuel tank skin and cleco ribs and attachment brackets to the baffle.
5.) Cleco second side of ribs to fuel tank skin
6.) Place in wing spar and put cleco and clamps in place to hold alignment with screw holes.
7.) Ensure zero gap between leading edge and fuel tank.
8.) Drilled fuel tank to W423
9.) Drilled attachment brackets with #12 from below using spar as a guide.

This worked great for me.

Steve Hurlbut
RV-7A
http://members.kingston.net/sjhdcl/rv7a.htm

Going forward, I'd love to see people talking about the "Hurlbut method." Sound like a plan?
 
"Checkoway" or "Hurlbut?"

Dan, I understand your request, but let's face it, you were blessed with a catchy last name. It's easy to remember, and it just has that special sound. People just don't want to talk about the "Hurlbut" method when they can talk about the "Checkoway" method. :)

But if I find myself talking about this topic, I'll honor your request. However, I may also add something like, "... also known by some folks as the Checkoway method." ;)
 
Hurlbut method

Sorry Dan. The last one was my fault. Guilty as charged.
You do have a catchy name but from now on I will make sure your name is not mentioned.
 
Interesting

Wow time flies. Thanks Dan - wish you were involved as much as you used to be - you have a natural building talent. Makes me feel old looking at Matronics postings.
 
(snip)
There ain't no Checkoway method. I didn't come up with anything. All the credit goes to Steve Hurlbut -- who posted it about 12 years ago.

(snip)
Going forward, I'd love to see people talking about the "Hurlbut method." Sound like a plan?

Sounds good. We could call it the "Checkoway plan".:)
 
I don't care who's name it goes by, but I am sure appreciative that you guys took the trouble to post about it. I just finished mine using the "method formerly known as Checkoway" an it was a life-saver!
 
Hey Dan! I still use your RV disk. Still helpful too.

ain't - - hmmmm, guess you have picked up some of that southern slang. Bet you are mashing buttons too.

Thanks for stopping in. You should splash your wit this way more often.
 
Thanks Anyway!

Well, to whomever came up with it, if a friend hadn't sent me this "method" I would still be trying to fit the tank baffle to the z brackets. You should see the stack of brackets I have that DIDN'T work! ;)
 
Checkoyway rocks

Hi Dan

10-4 on the credit for the infamous "Checkoway method" to fit my tanks. As usual, I check VAF for any hints prior to doing any significant ( and irreversible) ops on my 7. The aka "Checkoway method" worked great for me .. Even if you were just passing along the wisdom from others, thanks. It's all part of the RV community.

You still get free beer; and now Steve Huribut does, too! Sounds like a win win win.
 
Edge Distance ?

Hi Guys. Using the Hurlbut/Checkoway method, moving the #12 holes 1/16" away from the flange so that the socket can be placed over the bolt means that there is only an 8/32" edge distance, but a 9/32" is the minimum for a AN3 bolt (assuming a 1.5 edge distance factor). Is my math bad, or is this one of those moments where I should just "build on" because it is only one of the seven brackets? For the record, using the Vans method resulted in the same edge distance problem (yes, this is my second set). Thanks.
Tom.
 
Holes

Hi Guys. Using the Hurlbut/Checkoway method, moving the #12 holes 1/16" away from the flange so that the socket can be placed over the bolt means that there is only an 8/32" edge distance, but a 9/32" is the minimum for a AN3 bolt (assuming a 1.5 edge distance factor). Is my math bad, or is this one of those moments where I should just "build on" because it is only one of the seven brackets? For the record, using the Vans method resulted in the same edge distance problem (yes, this is my second set). Thanks.
Tom.

I used the centerline with no problem getting a socket on them. My set is thin wall though.
 
Hi Guys. Using the Hurlbut/Checkoway method, moving the #12 holes 1/16" away from the flange so that the socket can be placed over the bolt means that there is only an 8/32" edge distance, but a 9/32" is the minimum for a AN3 bolt (assuming a 1.5 edge distance factor). Is my math bad, or is this one of those moments where I should just "build on" because it is only one of the seven brackets? For the record, using the Vans method resulted in the same edge distance problem (yes, this is my second set). Thanks.
Tom.

I believe that step one in the Hurlbut method says: "No #12 holes"
 
Ok, so here's the plan. I'll move the 3/16 hole (yes Pete, I agree that drilling and reeming to final size gives far superior results in most situations to the #12) for the inboard bracket to 9/32 from the edge (1/32 over from center), then use a thin walled socket when installing (thanks Larry). I will only remove the remaining holes off center of I can't fit my ground down blind rivet puller in place on a test sample, as I'd like to keep the load path as centralized as possible (and yes, I have 14 potential test sample as this is my second set). I'll let you know how it goes.
Tom.
 
Close quarter puller

Ok, so here's the plan. I'll move the 3/16 hole (yes Pete, I agree that drilling and reeming to final size gives far superior results in most situations to the #12) for the inboard bracket to 9/32 from the edge (1/32 over from center), then use a thin walled socket when installing (thanks Larry). I will only remove the remaining holes off center of I can't fit my ground down blind rivet puller in place on a test sample, as I'd like to keep the load path as centralized as possible (and yes, I have 14 potential test sample as this is my second set). I'll let you know how it goes.
Tom.

Contact your EAA chapter and see if any 12 builders have one of these.
Close Quarter Rivet Puller
It worjs great on those z-bracket/baffle rivets.
DSC02784.JPG
 
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