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Lifting an RV12

Does anyone have experience lifting an RV 12 as it shows in the manual, with sturdy saw horses under the tail and nose section. Mine has only been lifted by the A&P using jacks under the wings (and cushioned boards) but I don't have jacks and would like to be able to service my own tires.

I think I would build a cushioned support a couple inches higher that the front belly of the plane, press down on the tail, put it the front support in place and lift up the tail with a jack of some sort under the tail cone using a cushioned board, then lower the rear tie down ring onto the support I've built.

Does this sound right?
 
The maintenance manual will give you the details of the stands to build, and how to get the plane onto them. There is a nice set of plans here: http://www.vansairforce.com/community/showpost.php?p=755417&postcount=13

I built my set 25" tall as specified, then put a couple layers of carpet on top. We occasionally increase the height an inch or so using foam pads cut from those interlocking floor mats.

Word of caution: WATCH OUT FOR THE TRANSPONDER ANTENNA when you slide the front stand in. They're cheap, but a PITA to replace.
 
See Page 1-17 of the maintenance manual or search for "Lifting and supporting".
If working by yourself, the nose can be lifted by hanging 60 or 70 pounds of weight on the tail tie-down. Slide the front sawhorse into place. Buy this scissor jack from Harbor Freight to lift the tail. $30 with 20 percent coupon. SKU: 96406 It extends to 23 inches. After lifting the tail, slide the rear sawhorse into place as shown in the maintenance manual.
 
Ted,

Good advice given by others.

I would like to add a couple of thoughts.

First ... I found if one builds two 25" sawhorses per the plans it will support the fuselage just fine, however it will not quite give enough height to get the main gear totally off the ground. I found I needed to make another sawhorse just a little taller. I use the 25" sawhorse aft and the 27 1/4" taller one forward.

Second ... It is really easy to purchase an inexpensive Harbor Freight tall jack and mount it on a platform to use for jacking up the tail cone.

Here is a link to my blog covering both items mentioned above.
http://www.dogaviation.com/2017/09/preparations-for-first-condition.html

Hope you find the above useful.
 
On my kit the extrusion with the threaded hole for a tie-down ring has a similar threaded hole facing upward, and there's a hole in the skin that could be enlarged for a lifting ring. Has anyone tried using that?
 
I made a fixture from angle iron that I bolt to the MLG leaf spring, it has a flat space on it for a bottle jack. It works great for tire and wheel bearing work.
 
I had seen the need for a lift during my build and decided a conversion of a Harbor Freight lift would work fine. To my surprise, it is so easy to use the new owner even uses it for a quick easy tire pressure check. If interested PM me for photos.
 
I do not lift my 12 by anything but a jack using the tie down point, but if I had to I would drill the tie down blocks from the top down to the threaded portion, insert eye bolts from the top to thread through the threaded portion of the block, put on an area washer and nut at the bottom and then lift by the eye bolts.
 
I do not lift my 12 by anything but a jack using the tie down point, but if I had to I would drill the tie down blocks from the top down to the threaded portion, insert eye bolts from the top to thread through the threaded portion of the block, put on an area washer and nut at the bottom and then lift by the eye bolts.

Lifting one side of the airplane by jacking up wing at tiedown bolt puts a concentrated force on the wing. Wing spar is a cantilever designed to have uniform loading spread over entire length. Sometimes spars are tapered and thinner toward the tip in order to save weight. Wing tip sees nearly zero load and root of spar sees entire load. I doubt if designer calculated strength to allow lifting with concentrated force at 2/3 length of spar.
 
Lifting an RV-12

To life my RV-12 to change a tire or brake, I use a floor jack. I have two pieces of 4 X 4 that I have cut at an angle to match the floor. I have rubber padding on one side of each piece. I then use a large C clamp to clamp both pieces securely to one landing gear. I then jack it up with the floor jack. It works well to jack up one side at a time. here is a picture.

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oNc.jpg
 
First ... I found if one builds two 25" sawhorses per the plans it will support the fuselage just fine, however it will not quite give enough height to get the main gear totally off the ground. I found I needed to make another sawhorse just a little taller. I use the 25" sawhorse aft and the 27 1/4" taller one forward.

Based on my experience and John's blog pictures the taller sawhorse needs to be placed in the REAR, not in the front.

I put mine on the horses pushing down on the tail to lift the nose and slide the front sawhorse in place. I use a couple of pillows on the ground under the tail tie down, for height, lay on my back and lift with my hands for the rear sawhorse. A second person is required for this method. Both directions, up and down on the tail only requires about 50 pounds of effort.
 
Interesting thought, Jim. The geometry of the lever arms when jacking up one side is a little different since the pivot point is the opposite tire. If I was worried I?d probably go through the gymnastics of calculating moment and compare it to 1G flight, but given that I can crouch under the wing and raise the tire off the ground using my back I don?t think the force involved is worth the math. I am much more feeble than the spar,😜
 
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