Author Topic: Placing Cadet on stands  (Read 2934 times)

Bill Poynter

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Placing Cadet on stands
« on: April 06, 2012, 11:54:13 AM »
My original intent was to write a posting about landing gear inspection and maintenance.  Since almost all landing gear maintenance requires that the plane be raised enough to remove the weight from the gear, I thought that we should discuss that first.  The PQ-8 maintenance manual addresses using saw horses to support the aircraft, but doesnít really get into some of the issues you should consider when jacking a Cadet.  Hereís the way I do it:

1.   Use really strong, stable saw horses.  Some landing gear maintenance requires getting in and out of the plane numerous times.  Iíve attached a photo of mine.  I havenít seen any store-bought ones that I would trust.  Every joint on mine is glued as well as either bolted or screwed together with deck screws. 
2.   I use an aircraft jack stand to support the tail.  This makes it easy to level the plane on the horses.  Place about 50 lb weight on the horizontal stab to hold it down on the stand. 
3.   I use a Harbor Freight engine hoist, connected by a rope to the engine mount at the firewall, to lift the plane so that the saw horses can be placed under the wings.
4.   Be sure that the aircraft is sitting level when you lower it onto the saw horses.  Lower it very slowly so that you can be certain that all weight is centered on the bottom of the main spar.  You donít want to damage a rib or the plywood skin.
5.   The PQ-8 manual suggests placing a sandbag between the saw horses and the main spars.  Iíve tried that and found that it causes too much pressure on the adjoining skin/fabric/ribs.  I just covered the top of my horses with carpeting.  This prevents localized damage to the spar area and if youíve leveled the plane properly, doesnít spread any load to the areas in front of and behind the spar.

If anyone has another way of raising their plane, please give us some suggestions.

Paul Rule

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Re: Placing Cadet on stands
« Reply #1 on: July 18, 2012, 12:56:47 AM »
Bill,

I just could not stomach (same as you) the idea of climbing in and out with the airplane titering on a saw horse...  I drilles a 3/8" hole in the heavy flange in the center of the large diagonal tubing assembly at the base of the wing.  This location is directly behind the main gear about 2.5" behind the spar centerline.  I installed a heavy duty eyebolt on spacers that sticks out through a hole drilled in the the inspection cover.  The eyebolt is strong enough to put a jack under and also I can put a link through it and use it for tie-down.  I had to make a set of custom jack stands that are shorter then standard Piper jack stands.  Works great... have to put about 30 lbs. of balast on the horizonal stab.

Clarke Tate

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Re: Placing Cadet on stands
« Reply #2 on: June 28, 2014, 09:13:21 PM »
I am attaching a few photos of my Culver Cadet up on jacks for a gear swing.
This Culver has tiedown and jacking points on the metal wing truss as indicated on page 16 of the PQ-8A Manual Figure 22.
The jacking point for the PQ-8A jacking is shown at station 91.

The engine hoist was merely attached as a backup to the 60 lbs. of sandbags on either side of the root of the horizontal stabilizer.
I really didn't want to experience the Culver tilting forward. There were also RV stabilizing jacks added with oak wood blocks and rubber facing on the spar near the gear as an added stabilizing point. I now think this was unnecessary.

There is wood blocking shown in Service Memo 19 Figure 5, at the fuselage and wing juncture. This seems like a preferable secondary point as opposed to my RV jack location in these photos. I have added that figure below.
« Last Edit: June 30, 2014, 05:47:01 PM by Clarke Tate »

Clarke Tate

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Re: Placing Cadet on stands
« Reply #3 on: June 30, 2014, 05:36:25 PM »
Knowing what I know now I will modify the wood blocks and the RV jacks. These will be placed as located in Service Memo 19 Figure 5, as a secondary support point. The aircraft is still jacked up by the station 91 jacking points as mentioned above. I'm not totally sure these secondary supports are needed, but I do find it provided some secondary support that doesn't seem to hurt. Peace of mind from all the weight being carried by the station 91 jacking points.
« Last Edit: June 30, 2014, 05:46:16 PM by Clarke Tate »

Keith U.

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Re: Placing Cadet on stands
« Reply #4 on: February 28, 2016, 06:22:27 PM »
Hi Bill,
Will you post the dimensions (height/length) of your saw horses?  I am almost ready to mount my wings and want to get the height of my horses right.  Thanks,
Keith

Keith U.

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Re: Placing Cadet on stands
« Reply #5 on: May 28, 2016, 09:55:39 PM »
My version of Bill's stands.  They work well enough, engine hoist for insurance.  did not want to build crooked horses so just blocked up one side to account for the dihedral.