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Quick Build fuselage (landing gear fittings)

 
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billz



Joined: 08 Jul 2009
Posts: 26
Location: Clinton, New York

PostPosted: Mon May 30, 2011 11:37 am    Post subject: Quick Build fuselage (landing gear fittings) Reply with quote

I'm finally getting around to working on my quick build fuselage. As I've read from others, you start with dis-assembly of some parts, follow the plans to make sure everything is done correctly as you reassemble. I've gotten to the task of removing the landing gear fittings. Boy is this a pain!!

I'm having trouble getting the bolts out and am wondering how I'm ever going to get them back in, when the time comes. Any insights on the process of removing these bolts and then getting them back in would be greatly appreciated. I'm sure there are many techniques that work better than what I've been trying.

Thanks in advance.


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Mauledriver(at)nc.rr.com
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PostPosted: Mon May 30, 2011 12:07 pm    Post subject: Quick Build fuselage (landing gear fittings) Reply with quote

Don't do it? Not being trying to be facetious but some disassemble,
some don't.

On 5/30/2011 3:37 PM, billz wrote:
Quote:


I'm finally getting around to working on my quick build fuselage. As I've read from others, you start with dis-assembly of some parts, follow the plans to make sure everything is done correctly as you reassemble. I've gotten to the task of removing the landing gear fittings. Boy is this a pain!!

I'm having trouble getting the bolts out and am wondering how I'm ever going to get them back in, when the time comes. Any insights on the process of removing these bolts and then getting them back in would be greatly appreciated. I'm sure there are many techniques that work better than what I've been trying.

Thanks in advance.


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dmaib(at)mac.com
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PostPosted: Mon May 30, 2011 2:19 pm    Post subject: Quick Build fuselage (landing gear fittings) Reply with quote

Early in the program, some builders found a few odds and ends under
the floorboards when they opened them up. (clecos, rivits, etc.)
However, it seems that later on this problem was solved at the QB
factory. I started to take mine apart and had a terrible time with
the left gear weldment. It was clean under the floor, so I elected
not to open up the right side. I felt like I was risking doing some
damage while undoing a job that I had paid to have done by the
factory. No regrets in my decision and if I were to build another one
I would not consider doing it. Some folks planned to put in sound
deadening material or insulation while having the floors out. I think
that someone on the forum has figured out a way to do that without
taking the floors up. In the end, of course, this is a decision you
get to make. There are several builders who easily and quickly
removed and reinstalled the gear weldments and floors. I was not one
of them!
Just my $.02 worth.

David Maib
40559
Flying

On May 30, 2011, at 3:37 PM, billz wrote:

Quote:


I'm finally getting around to working on my quick build fuselage.
As I've read from others, you start with dis-assembly of some
parts, follow the plans to make sure everything is done correctly
as you reassemble. I've gotten to the task of removing the landing
gear fittings. Boy is this a pain!!

I'm having trouble getting the bolts out and am wondering how I'm
ever going to get them back in, when the time comes. Any insights
on the process of removing these bolts and then getting them back
in would be greatly appreciated. I'm sure there are many
techniques that work better than what I've been trying.

Thanks in advance.


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http://forums.matronics.com/viewtopic.php?p=341506#341506




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dlm34077(at)q.com
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PostPosted: Mon May 30, 2011 3:43 pm    Post subject: Quick Build fuselage (landing gear fittings) Reply with quote

Why disassemble; you paid to have someone else assemble and two other
compliance inspections performed. Make a visual inspection but don't undo
something for which you already paid. Some take the fuel tanks off the QB
wings; again why? They have already been tested at the QB facility. If they
leak, it will be your problem now or at some future time.It is possible to
create a problem during the tank removal. Some will install a stall warning
system; others will rely on an EFIS warning. If you fly the airplane and do
not feel the impending stall you are comatose or embalmed. The stick shakes
very noticeably. My point is taking everything apart costs you time and
money. Taking things apart can also cause problems noticed or unnoticed
during reassembly. That's the reason the post annual inspection test flight
is one of the riskier of the year.
---


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Jim Berry



Joined: 10 Jan 2006
Posts: 237
Location: Denver

PostPosted: Mon May 30, 2011 4:04 pm    Post subject: Re: Quick Build fuselage (landing gear fittings) Reply with quote

I was one of those that put insulation under the floor. If you want to go that route you can drill out some of the rivets and pull the aft edge of the floor boards up, without completely removing them. Use the rivet lines on the bottom to make templates for pieces of insulation to fit between the stiffeners.

If you don't want insulation, just tape a section of 1" tubing to your shop vac. and slide it through the lightening holes to suck out anything left under the floors by the QB guys.

Either way, there is no need to remove the landing gear fittings.

Jim Berry
N15JB


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Kellym



Joined: 10 Jan 2006
Posts: 1705
Location: Sun Lakes AZ

PostPosted: Mon May 30, 2011 4:45 pm    Post subject: Quick Build fuselage (landing gear fittings) Reply with quote

No. Do not loosen and retorque. First of all you cannot accurately
measure torque that was applied. All you are doing is removing more of
the cad plating on the bolt. An AN-3 properly torqued, when loosened
later will likely take 50-80 in/lbs to break free, even though only
25"/lbs plus the resistance of the locknut were applied to begin with.
Huge waste of time that accomplishes nothing.
It is easy to remove the few pop-rivets that hold the floor, to vacuum
underneath and a bit harder to push insulation in, but very doable
without removing fittings.
On 5/30/2011 5:25 PM, Phillip Perry wrote:
Quote:
I took one of mine out because of a screw up that I made. It was a
nightmare and there wasn't anything to see after I pulled it (I pulled
the floor skin "just because").

I'd leave them right where they are, but I'd consider loosening all of
the AN hardware to neutral and then re-tourqing so you know they're
correct.

Phil

*
*


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billz



Joined: 08 Jul 2009
Posts: 26
Location: Clinton, New York

PostPosted: Mon May 30, 2011 5:07 pm    Post subject: Re: Quick Build fuselage (landing gear fittings) Reply with quote

I appreciate all of your comments. It's great to learn from experience.

I'm all for taking the simple approach. I'm not planning to put insulation under the floor, but wasn't sure if I needed access for some other reason. Looks like a little cleaning and on to the next step.

Thank you,
Bill


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maca2790



Joined: 26 Jan 2011
Posts: 59
Location: Australia

PostPosted: Mon May 30, 2011 5:43 pm    Post subject: Re: Quick Build fuselage (landing gear fittings) Reply with quote

I know the feeling, I took the bolts out of my QB last week. It took nearly 6 hours to dissemble everything. There was a lot of damage done to the bolts during the process and they will need to be replaced.

I reamed out the holes that were tight and left the others alone but it left me wondering how on earth they put the bolts in with them being so tight?

Under the floor pans there was a little dust and some aluminium savings but otherwise it looks pretty good. I'm not planning on Insulating I just wanted to prime under the floor pans.

cheers
John MacCallum
QB 41016
VHDUU


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Kellym



Joined: 10 Jan 2006
Posts: 1705
Location: Sun Lakes AZ

PostPosted: Mon May 30, 2011 6:29 pm    Post subject: Quick Build fuselage (landing gear fittings) Reply with quote

If you do the factory stall warning vane, removal of the left tank is necessary. Regardless of aerodynamic warning, IMHO, either an AOA or stall warning system should be mandatory, as it is for certified planes. Not every pilot is observant of aerodynamic warnings when occupied with other tasks in the cockpit, and a horn, voice or flashing light is better than nothing.
There is nothing about removing a tank, short of dropping it that is likely to have one bit of effect on how well the tank is sealed. None of the fasteners penetrate the sealed portion. A tank is 100% easier to do a thorough leak check with it off the wing. If you have one that leaks, you will want to be able to negotiate with Vans ASAP, not months after delivery. Just my opinion and what I did with mine. Being owner built and maintained, all are welcome to make their own choices.
Kelly

[img]cid:part1.08030009.03010209(at)aviating.com[/img]

On 5/30/2011 4:40 PM, DLM wrote:
Quote:
- Some take the fuel tanks off the QB wings; again why? They have already been tested at the QB facility. If they leak, it will be your problem now or at some future time.It is possible to create a problem during the tank removal. Some will install a stall warning system; others will rely on an EFIS warning. If you fly the airplane and do not feel the impending stall you are comatose or embalmed. The stick shakes very noticeably. My point is taking everything apart costs you time and money. Taking things apart can also cause problems noticed or unnoticed during reassembly. That's the reason the post annual inspection test flight is one of the riskier of the year.
-




























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dhmoose



Joined: 22 Nov 2010
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PostPosted: Tue May 31, 2011 4:54 pm    Post subject: Re: Quick Build fuselage (landing gear fittings) Reply with quote

Just did this a few weeks ago. When I noted that all of the QB bolts had torque seal BUT the landing gear bolts, the floors can't be removed without removing the landing gear, and I want insulation under the floorboards...I decided to remove the landing gear mounts. I It was very difficult to remove both gear mounts due to the incredible force on some of the bolts. You can tell that some bolts were doing 100% of the work and others were doing 0% (as evidenced by the pressure to remove and the surface cad lost). In the end, they came out with some damage to the bolt heads (from the plier used to grab and pull). A few bucks worth of bolts from Vans and I was feeling good about my ability to access the floors. No odd findings, but good access to verify everything and add insulation. I fabricated drifts out of the old bolts (see image attached) which my tech counselor said would be very helpful in aligning everything for reassemby. Reassembly is around the corner...so I'll let everyone know if it was more/less difficult then removal. In the end, I do not feel it is imperative to remove the gear, but no harm is caused by doing so.

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Bob Turner



Joined: 03 Jan 2009
Posts: 885
Location: Castro Valley, CA

PostPosted: Tue May 31, 2011 8:31 pm    Post subject: Re: Quick Build fuselage (landing gear fittings) Reply with quote

BTW, my QB fuel tanks came installed - but with bolts that were one size too long! To compensate, there were 2 washers under each bolt head.

I thought this was a potential disaster waiting to happen. 10 years from now, someone (me) pulls the tanks, sees the extra washer, and throws it away. Now the bolts bottom out before coming tight.

Whether you choose to pull the QB stuff apart or not is your choice (I left my gear mount alone) but do check everything.


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nukeflyboy



Joined: 05 Jan 2008
Posts: 162
Location: Granbury, TX

PostPosted: Wed Jun 01, 2011 12:25 pm    Post subject: Re: Quick Build fuselage (landing gear fittings) Reply with quote

Don't take apart anything that you don't have to. I didn't understand the comment about removing the right fuel tank to install the stall warning. I didn't have to for it or for a heated pitot.
You can leak test the fuel tanks with them installed.
You should think about your electrical distribution and the need for conduit runs under the floor. This is a convenient place to run cable out of the way and the wires can be pulled later. You can also consider insulating the floor at the same time, though that is clearly optional.


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Kelly McMullen



Joined: 16 Apr 2008
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PostPosted: Wed Jun 01, 2011 12:44 pm    Post subject: Quick Build fuselage (landing gear fittings) Reply with quote

If you read the plans, the left(not right) fuel tank is called out to be removed to install the stall warning. Otherwise you are trying to do a knee scope with an endoscope designed for colonoscopy. Sure, you can avoid it, but the scrapes you get will be worse than pulling the tank. Other than being a fair number of screws and bolts, removal simply is not difficult, and does mean you can leak check with soapy water all surfaces while rotating tank to have tested area on top. It is not in the class of trying to remove the gear weldments.
Kelly
Finish/FWF+never ending fiberglass hell

On Wed, Jun 1, 2011 at 1:25 PM, nukeflyboy <flymoore(at)charter.net (flymoore(at)charter.net)> wrote:
Quote:
--> RV10-List message posted by: "nukeflyboy" <flymoore(at)charter.net (flymoore(at)charter.net)>

Don't take apart anything that you don't have to.  I didn't understand the comment about removing the right fuel tank to install the stall warning.  I didn't have to for it or for a heated pitot.
You can leak test the fuel tanks with them installed.
You should think about your electrical distribution and the need for conduit runs under the floor.  This is a convenient place to run cable out of the way and the wires can be pulled later.  You can also consider insulating the floor at the same time, though that is clearly optional.

--------
Dave Moore
RV-6 flying
RV-10 QB - FWF




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PostPosted: Thu Jun 02, 2011 4:46 am    Post subject: Re: Quick Build fuselage (landing gear fittings) Reply with quote

I did not pull the floors. You can access the front ones through the lightening holes under the seats, For the back ones I drilled a few holes at one end. I used a big magnet, vacuum, and borescope - saw nothing. I then filled them with Abesco FP200 fire proof foam. It is closed cell, won't burn, and gives a solid feel to the floor. Pretty pink color matches the canopy (g). Only expands about 2x. Here is the manufacturer:
http://www.abesco.net/productus/products/fp200.php

The suggestion about conduit is important. Get as much conduit in the baggage floors as you can.

John


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dhmoose



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PostPosted: Thu Jun 02, 2011 6:13 am    Post subject: Re: Quick Build fuselage (landing gear fittings) Reply with quote

Dave, what wire/cable are you running under the front floor panels? It seems like there isn't anything passing through that area and since I'm about to close it up, I thought I'd ask. What about antennas? I was planning the transponder antenna to go in the midline (under the tunnel) , not under the floor panels of the pilot/right seater. Thanks.
nukeflyboy wrote:
Don't take apart anything that you don't have to. I didn't understand the comment about removing the right fuel tank to install the stall warning. I didn't have to for it or for a heated pitot.
You can leak test the fuel tanks with them installed.
You should think about your electrical distribution and the need for conduit runs under the floor. This is a convenient place to run cable out of the way and the wires can be pulled later. You can also consider insulating the floor at the same time, though that is clearly optional.


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PostPosted: Thu Jun 02, 2011 6:28 pm    Post subject: Re: Quick Build fuselage (landing gear fittings) Reply with quote

David,
I couldn't recall which floor panels were installed with the QB and which ones I did. You are correct - there is no need to run anything under the front floorboards. I have run quite a bit under the rear seat pans and baggage floor. My comm antennas are attached on the belly just aft of the rear wing spar with the coax running forward just above the rear spar and then to the side panel (see photo).
There is plenty of room to run wires along the sides starting forward and running aft to the rear seat side panel. At this point my wires dive under the floor and emerge aft of the baggage compartment at the battery.


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PostPosted: Thu Jun 02, 2011 6:28 pm    Post subject: Re: Quick Build fuselage (landing gear fittings) Reply with quote

David,
I couldn't recall which floor panels were installed with the QB and which ones I did. You are correct - there is no need to run anything under the front floorboards. I have run quite a bit under the rear seat pans and baggage floor. My comm antennas are attached on the belly just aft of the rear wing spar with the coax running forward just above the rear spar and then to the side panel (see photo).
There is plenty of room to run wires along the sides starting forward and running aft to the rear seat side panel. At this point my wires dive under the floor and emerge aft of the baggage compartment at the battery.


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PostPosted: Fri Jun 03, 2011 10:11 pm    Post subject: Re: Quick Build fuselage (landing gear fittings) Reply with quote

Dave, Thanks for the pictures. It's always nice to get the visual! Today, it was front floors but the baggage/rear floors are around the corner. I'm excited to get to the conduit. Thanks again, David

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