Any recent Smooth belly mod for m20e

[Hradec]

Anyone do the smoother belly mod recently on an M20e?  

I'm in the process of changing the aft stub spar due to corrosion. I have to drill out the 2 riveted panels in the belly and unscrew the other panels. They are dirty, grimy, need paint. A dozen different fastener sizes. Riveting the 2 panels back in will be time consuming.

Is this mod a sensible use of time and money? I will be doing all the work myself (ap/ia minimal GA experience) 

I was looking at the lasar mod. 

No change in wt and balance. 

I believe 4 panels are removed, some stringers, lots of screws and clipnuts.

Glenn

[cctsurf]

I love the idea, I just can't justify spending the AMUs.

Cuts a LOT of screwing around out of annuals.

What's your time worth (now and later)?

[Hank]

My C has the one piece fiberglass belly. There are 52 screws that hold it on, each countersunk through a dimpled washer.

For some more money, a carbon fiber belly is available with dzus fasteners, for easier removal and reinstall.

[carusoam]

Very often the one piece panel is considered an upgrade...

If something happens to the existing belly panels,the one piece makes a lot of sense...

One advantage of the plastic panel... antennas can be mounted on the other side... (?)  where. Aluminum would block the signal...

PP thoughts only, not a mechanic...

Best regards,

-a-

[Hradec]

4 hours ago, Hank said:

My C has the one piece fiberglass belly. There are 52 screws that hold it on, each countersunk through a dimpled washer.

For some more money, a carbon fiber belly is available with dzus fasteners, for easier removal and reinstall.

Who makes/markets the carbon fiber belly for the m20e? 

[Hank]

4 hours ago, Hradec said:

Who makes/markets the carbon fiber belly for the m20e? 

I don't recall, but I've seen ads for it. It is not inexpensive. 

[mike_elliott]

9 hours ago, carusoam said:

Very often the one piece panel is considered an upgrade...

..and very often a one piece belly and 3 blade prop are the sign of a previous gear up, often not recorded in the logs. Not that this in itself is bad if the repairs were properly done to the gear, etc. but often this is embellished as a feature, when it really could be a detriment.

[M20F-1968]

There is a one piece belly on e-bay for sale.  I do not know for which model.  It possibly can be shorted if need be.  Fiberglass can be remodeled easily.

The one piece belly mod is not for the faint at heart.  There is structure removed and new structure installed.  You will need documentation such as an STC or DER approval.

 

John Breda

[Hradec]

42 minutes ago, M20F-1968 said:

There is a one piece belly on e-bay for sale.  I do not know for which model.  It possibly can be shorted if need be.  Fiberglass can be remodeled easily.

The one piece belly mod is not for the faint at heart.  There is structure removed and new structure installed.  You will need documentation such as an STC or DER approval.

 

John Breda

I couldn't remember where I saw it for sale, thanks.

At $2500 the one at lasar is new and cheaper.

 

[Hradec]

2 hours ago, mike_elliott said:

..and very often a one piece belly and 3 blade prop are the sign of a previous gear up, often not recorded in the logs. Not that this in itself is bad if the repairs were properly done to the gear, etc. but often this is embellished as a feature, when it really could be a detriment.

I got my plane for next to nothing, had 2 incidents one in 1965 and then again in the 70s. So much monkey motion in the belly of these planes. Will make it much easier for me to maintain  it. Going to have the belly pulled and riveted panels removed. I think it will be a time saver for reassembly and then again a time saver in the future.

[Tim Jodice]

3 hours ago, Hradec said:

I got my plane for next to nothing, had 2 incidents one in 1965 and then again in the 70s. So much monkey motion in the belly of these planes. Will make it much easier for me to maintain  it. Going to have the belly pulled and riveted panels removed. I think it will be a time saver for reassembly and then again a time saver in the future.

A HUGE time saver in future annuals. My friend has a 67 F with around 300 (kidding but it is a lot) regular screws. I have a 85 J with (I think)36 1/4 cam locks. I have never removed all of the screws on his plane but you can take a 1 piece belly pan off alone in 5-10 minutes.

No doubt it is a big deal to modify the airframe but it sounds like you might be almost there labor wise doing the required repairs. If you do it please post some pictures I would love to see what it takes.

[Guest]

I did one of the aftermarket smooth belly mods on my second E model and switched the fasteners from 10-32 screws to 1/4 turn Southco fasteners.  While not quite as nice as the Mooney factory kit it works quite well.  The factory kit is a flush installation, where the aftermarket version fit on top of the remaining belly skins.

If the labour is your own, it’s worth doing.

Clarence

[Hradec]

On 10/16/2020 at 8:56 PM, Hank said:

My C has the one piece fiberglass belly. There are 52 screws that hold it on, each countersunk through a dimpled washer.

For some more money, a carbon fiber belly is available with dzus fasteners, for easier removal and reinstall.

How thick is the panel? How thick at the fwd leading edge and aft edge?

[Hank]

2 hours ago, Hradec said:

How thick is the panel? How thick at the fwd leading edge and aft edge?

It's a pretty uniform thickness, maybe tapered a little bit at the front. But I didn't go to the airport today; memory says it's fairly thin. Maybe 1/4"?

Here's a picture with it off at annual, sure does make it easy to clean the belly!

[Hradec]

1 hour ago, Hank said:

It's a pretty uniform thickness, maybe tapered a little bit at the front. But I didn't go to the airport today; memory says it's fairly thin. Maybe 1/4"?

Here's a picture with it off at annual, sure does make it easy to clean the belly!

Thanks for sending the picture.

I was just at the hangar under the airplane and just drilled out the rivets of the 2 center belly panels realizing it's going to be a pain to reinstall. I have a copy of the stc and looks like some stringers and formers get removed. It is going to allow for amazing access. Really looks like it will be a time saver in reassembly after my aft stub spar replacement and in the future for lubrication and inspect. Looks like I'm going to pull the trigger.

What antenna is mounted to your panel?

[Hank]

1 hour ago, Hradec said:

Thanks for sending the picture.

I was just at the hangar under the airplane and just drilled out the rivets of the 2 center belly panels realizing it's going to be a pain to reinstall. I have a copy of the stc and looks like some stringers and formers get removed. It is going to allow for amazing access. Really looks like it will be a time saver in reassembly after my aft stub spar replacement and in the future for lubrication and inspect. Looks like I'm going to pull the trigger.

What antenna is mounted to your panel?

It makes annual inspection pretty easy. Just remove all screws except 4 (leave 2 about a foot from each end, one on each side). Roll a stool or slide a box underneath, remove the last screws, unplug the antenna (push, twist, pull off) and slide it out. Reinstallation is the same, prop it up and connect the antenna,  start some screws, then get them all started before trying to run any all the way in. Yes, I've been seating screws and remembered the antenna    just back out most of them, remove some at the back and reach in . . . .

The antenna is a big white one, with a quick-disconnect coaxial cable. This is the inside. Looks like I cleaned off grease drippings from the jackscrew--gotta get fixed up for photos, right?

[Hank]

6 hours ago, Hradec said:

How thick is the panel? How thick at the fwd leading edge and aft edge?

I have no idea why I took this picture several years ago, but it shows the rear of the belly panel and the sometimes aggravating drain that pokes through it. As you can see, it's not thick at all.

The panel starts about an inch toward the camera from the drain pipe, and is in front of the large white antenna. 

[Hradec]

1 hour ago, Hank said:

I have no idea why I took this picture several years ago, but it shows the rear of the belly panel and the sometimes aggravating drain that pokes through it. As you can see, it's not thick at all.

The panel starts about an inch toward the camera from the drain pipe, and is in front of the large white antenna. 

Thanks for the pics and info. Was trying to convince myself it was worth it. Just got my ppl. This plane I bought hasn't flown in 5yrs. Friend says just make it airworthy and fly it save some money  if I have cam corrosion. I I however feel if I am there, I'm going to make it right and make it easy for me.

By the way, lasar was kind enough to send me a copy of the stc to determine if it would be a helpful purchase in my aft stub spar endeavour. This stc says the tube does NOT go through the belly panel. Not sure how they want it routed.

 

[carusoam]

Is that the roof vent drain they are discussing?

They are describing exiting out the wing...

The roof vent drain, runs down the side of the wall and can pretty much drain anywhere...

+1 on save your dough...

It is a long way to AW!

Once there... save your dough... there are so many other things needed!

When you have a stack of AMUs... you get to decide which luxury you are going to spend it on...

PP thoughts only, not a mechanic...
 

best regards,

-a-

[cogboxer]

We just finished this on my ‘62 C. All told the hours exceeded the estimated 70 by a fair amount, but I wouldn’t say anything was all that difficult. Lots of drilling out of rivets, and installing nutplates. The documentation isn’t bad. The most useful tool we had was the hole-finder my mechanic made out of a strip of sheet metal and a screw with a hole drilled through it — that helped us position the fastener holes properly on the panel.

I’m pretty pleased with how it turned out. Now we’re thinking about what antenna we can move to the belly. First flight should be Sunday. 

[Hank]

6 hours ago, cogboxer said:

I’m pretty pleased with how it turned out. Now we’re thinking about what antenna we can move to the belly. First flight should be Sunday. 

Glad yours went well. Just be sure to leave some slack in the antenna wiring so the belly can be dropped far enough to reach inside, and use an easy-to-remove-while-blind coupling in the lead. I drop the belly about 6", reach inside with one hand and disconnect the antenna then slide the whole belly pan out from under the plane.

[Hradec]

Does anyone remember how much the short body smooth belly stc for the fiberglass panel was from LASAR?

I finally need one already made the modifications to my plane to accept it.

I called LASAR and they are in the process of having some faa approval for them to mfr them at their new location. They were not sure of the pricing yet. some numbers they mentioned  were really really high. 

Does anyone recall what they paid and when? 

Thanks

Glenn 

64E putting it back together after spar cap and stub spar replacement 

[hammdo]

Glad to hear the corrosion fix is done!

The one on my Mooney was installed years ago and looks like it was ~$1500 at the time of the gear up fix (2006). Not sure who has them now besides LASAR. Maybe @Alan Fox might?

-Don

[Fly Boomer]

4 hours ago, Hradec said:

putting it back together after spar cap and stub spar replacement 

That's some major work.  Who is doing it?

[hammdo]

@Hradec did — has a thread on here showing him doing the work - he is an A&P…