M20F cribbing/trusses

[Jpravi8tor]

Greetings fellow MF’ers (Mooney Flyers) has anyone designed built or used wooden cribbing to support the aircraft while removing the gear for overhaul? Are there plans available? Any pictures thoughts comments advice welcomed

[A64Pilot]

Strong saw horses and blankets.

You can get much more complex of course, but I assume your leaving it on jacks and just want the backup?

[Jpravi8tor]

Seriously? That was

[Fly Boomer]

2 minutes ago, Jpravi8tor said:

Seriously? That was

Read up on this.  It's slightly more involved to avoid damage to your wing.

[Jpravi8tor]

I plan on discussing this with as many people as I can, I would like to find an instance where someone designed a crib, I suppose I will make a wing contour template or use airbags or old mattresses on tables 

Edited April 23, 2022 by Jpravi8tor

[Guest]

Mooney installed a set of very convenient jacking points on the main wing spars used to support the plane during gear work.  The only Mooney to use saw horses that I’ve heard of is a Mite.

Don't damage your wings by doing it wrong.

Clarence

[A64Pilot]

Honesty thick blankets, old style quilted furniture blankets, several or old mattresses will work, I’ve done it on much larger, heavier aircraft. I’ve even recovered a U-21 under a Skycrane using primarily old mattresses at Savannah Army Airfield, by I, I mean I was part of the team, not the guy in charge, just a worker bee. I was a PFC at the time. We didn’t damage it either, removed the flaps as the straps used for lifting would probably damage them

Idea is obviously distribute the load, or concentrate it on the spar, jack point covers the spar, old mattresses will distribute the load. I’d leave it on jacks myself, but don’t see any harm at all in having a backup

[N201MKTurbo]

I’ve taken all three gear legs off of a couple of Mooneys. I just leave it on jacks.

[EricJ]

My hangar neighbor with an M20A puts his on sawhorses, as there are no jack points on those.   Apparently that's what the manual says to do.

With a metal wing there's not much reason to not leave it on a jack instead.   If jacks are not available or financially feasible, I'd still use the jack points and just figure some method to support the airplane there.   That's what they're for.

[carusoam]

11 hours ago, Jpravi8tor said:

Greetings fellow MF’ers (Mooney Flyers) has anyone designed built or used wooden cribbing to support the aircraft while removing the gear for overhaul? Are there plans available? Any pictures thoughts comments advice welcomed

Jpr,

Find M20Doc’s post above… click on his avatar… find the follow button… he is one of the most valuable resources around here for your project…   

MSers like to build things…

Group thinking takes a while to get All of the bugs out of the initial discussion…

This has been done a few times… 

Look up building jacks for your Mooney… safety collars are a must… for long term storage… a big safety item for all piston like jacks…

And building the tail tie down… make sure what you bolt it to has the proper thread qualities…

 

It is incredibly disappointing when a plane falls off the jacks…

 

Cradles are most often used for off field recovery, and they are mostly temporary…

+1 for using proper Jack points and tie downs…

There are to many pics around here of jacks poking through the wing, and props bent pointing at the floor…

 

Jacks are good at leaving you with the most area to work under the wing… compared to a saw horse…

Jacks are perfect for refurbing Mooney legs…

 

There is probably a really good explanation for this in the Maintenance Manual… as well…

Some times re-inventing the wheel sounds better than it really is… 

PP thoughts only, seen a lot of this around here…

There may even be pics of saw horses too… to support 3k#s of airplane… they better be strong… 

Best regards,

-a-

 

[Jpravi8tor]

Thanks for all the input, I might have to leave the aircraft outdoors when removing the gear thus the need for additional stability. I need to source or make some jacks and jackpoints. I have seen some posts about jack point construction and will continue my research. When I start this project I will be documenting the progress here.

[A64Pilot]

Due to winds you really, really don’t want to leave one outside when not supported on its landing gear. If the winds are 10 kts and I have to change a tire outside, I’ll wait until tomorrow.

As a kid I did something stupid and was trapped under a farm tractor, it was quite awhile before I could work under a car without being nervous.

For that reason I guess I could understand wanting a secondary support. But if this cribbing is meant to be primary, how are you getting the airplane up in the air without jacks?

A couple of short strong sawhorses with a piece of plywood and a mattress or anything thick and soft would spread the load enough to not cause damage, but jacks are what’s meant to be used and inside, if the winds blowing even moderately hard, don’t even open the doors.

Jack points are in the airplane, remove the tie downs, that’s the jackpoints, do not use the tiedowns, the ring may break. Although I don’t have the manual in front of me procedures for jacking are always in it, and usually in the section known as servicing. Don’t do or plan anything until your familiar with that section.

‘Apparently Chapter 7

Edited April 24, 2022 by A64Pilot

[A64Pilot]

This is I guess the whole procedure for my J model, I do not know if yours differs

 

[EricJ]

1 hour ago, Jpravi8tor said:

Thanks for all the input, I might have to leave the aircraft outdoors when removing the gear thus the need for additional stability. I need to source or make some jacks and jackpoints. I have seen some posts about jack point construction and will continue my research. When I start this project I will be documenting the progress here.

Lasar sells jackpoints as well as the combination tie down/jack point that you can just leave in all the time.

https://lasar.com/tie-downs/tie-down-jack-point-combo-ss-tie-down-wing

[A64Pilot]

2 hours ago, EricJ said:

Lasar sells jackpoints as well as the combination tie down/jack point that you can just leave in all the time.

https://lasar.com/tie-downs/tie-down-jack-point-combo-ss-tie-down-wing

I have those and they work well, but if I left mine tied down I’d have to take a Dremel and smooth the edges where the rope goes through as I think over time it might cut a rope as is. I thought it interesting that your supposed to remove the tie downs before flight, not that I do.

Clicking on the LASAR link came up with this https://www.mooney.com/wp-content/uploads/2020/12/SIM20-114.pdf

I wonder why the change from lifting on the Prop? I used to lift from the engine mount on my Maule to put on the Bushwheels, engine lifting point scared me, but I guess maybe a Mooney front end weighs less than the engine maybe?

Edited April 24, 2022 by A64Pilot

[EricJ]

4 hours ago, Jpravi8tor said:

Thanks for all the input, I might have to leave the aircraft outdoors when removing the gear thus the need for additional stability. I need to source or make some jacks and jackpoints. I have seen some posts about jack point construction and will continue my research. When I start this project I will be documenting the progress here.

If it needs to be outside definitely make something with a very broad base.   You could make a wooden tripod or pyramid with a connected base that can't topple but has something for the jackpoint to sit on and potentially move around a bit.  I wouldn't trust normal jacks for that if it might be outside in the wind.   That's a tricky problem, and you're right that maybe something broader than the jackpoint might be a good idea, but I'd be very careful about what parts of the wing structure are bearing the weight, especially if it does move in the wind a bit.

Airliners get supported sometimes on ricking towers built from timbers like railroad ties, so it's definitely doable, but proceed with caution.

[Fly Boomer]

3 hours ago, A64Pilot said:

Jack points are in the airplane

These are the "traditional" jack points

 

[carusoam]

Something to consider when parked outside…

1) Weather is often taken into account…

2) Prop blast can be considered as well… all kinds of students doing wacky things over time…

3) The one that surprised me was helicopters air taxiing by….

4) Then there was the goofball air taxiing by in an R66…

5) Nothing says you’re an ingenious helicopter pilot like flying one like an R22….

6) 2700# suspended in the air as it creeps by your plane on jacks…. 
 

7) Jack stands connected by a threaded bolt may be a good idea…

8) Expect that a pilot taxiing by in his rented R66 thinks YOU have considered all of HIS actions…

 

PP thoughts only, not a mechanic…

Best regards,

-a-
 

 

Edited April 24, 2022 by carusoam

[A64Pilot]

23 minutes ago, Fly Boomer said:

These are the "traditional" jack points

 

OK jack point receptacles then? Until,I bought the LASAR ones, I’ve always taken a bolt and ground the head.

You want to get scared? Take a look at C-210 jack points, held on by sheet metal screws, then you have to have a jack about at least eight ft tall as the wing is about six to start with so even a tall jack with that long of an extension is wobbly

https://youtu.be/FMFWIP0B6wA

This is a 182, a 210 has to be even higher so those mains don’t drag

 

Edited April 24, 2022 by A64Pilot

[Guest]

A unique set of home made jacks I spotted in a hangar today.  Turn the two handles to spin the nut to extend the giant screw to lift the plane.

Clarence

[A64Pilot]

Those don’t bleed down either, just may need a pipe to work it, wonder if those are square threads?

AKA jack stands, screw type

https://www.amazon.com/s?k=screw+jack+stands&crid=PNXCEJTADSZM&sprefix=screw+jack+stands%2Caps%2C214&ref=nb_sb_noss_1

Edited April 24, 2022 by A64Pilot

[Fly Boomer]

1 hour ago, A64Pilot said:

You want to get scared? Take a look at C-210 jack points

Yikes!  I wouldn't walk near that thing, let alone swing the gear.

[Guest]

12 hours ago, A64Pilot said:

OK jack point receptacles then? Until,I bought the LASAR ones, I’ve always taken a bolt and ground the head.

You want to get scared? Take a look at C-210 jack points, held on by sheet metal screws, then you have to have a jack about at least eight ft tall as the wing is about six to start with so even a tall jack with that long of an extension is wobbly

https://youtu.be/FMFWIP0B6wA

This is a 182, a 210 has to be even higher so those mains don’t drag

 

Just to keep things accurate, the two jack pads are screwed to the wing with three 10-32 structural screws, not sheet metal screws.  None the less the base of those jacks is way too small.

Clarence

[A64Pilot]

Making the base larger wouldn’t do much as then your off of the spar, but it’s been done that way for a long time, and I guess few have been dropped. If you watch the 182 vid notice how the guy who flips the gear switch bolts when he does.

Just gives me the willies is all, I really, really hated to swing the gear on the 210, only did it once, other Annuals I contracted out. You can’t even use a swing set and have a backup as the engine mount isn’t steel tubes.

It’s been years but I think they were #8 screws?

Four 1/8” bolts hold the landing gear onto an OH-58 helicopter and we would have four people stand on the skids to pull enough torque to see when the bled valve closed, after noticing what held the gear on, we piled into the back seat instead, I can only imagine one of those bolts breaking, dynamic rollover with four standing around.

Notice how the jack pads on the 210 aren’t pointy? You don’t need pointy.
 

 

 

[Shadrach]

20 hours ago, A64Pilot said:

OK jack point receptacles then? Until,I bought the LASAR ones, I’ve always taken a bolt and ground the head.

You want to get scared? Take a look at C-210 jack points, held on by sheet metal screws, then you have to have a jack about at least eight ft tall as the wing is about six to start with so even a tall jack with that long of an extension is wobbly

https://youtu.be/FMFWIP0B6wA

This is a 182, a 210 has to be even higher so those mains don’t drag

 

So much that is sketchy about this. The jacks, the height, the fact that significantly more clearance is required to swing the gear than is necessary to raise it off the floor. So many ways things could go sideways.