Stripped screw holes

[Supercop0184]

What’s the best fix for some of these cowl and avionics access cover screw holes   Right in front of the windshield. that just won’t hold a screw? 64C model. Seems like several of each type are stripped and I’m OCD enough that it’s got to be fixed. 

 

Thanks! 

[Hank]

You can clip in a nut plate of the correct size, or take the lazy way out and use a larger screw. But you'll need a "supervising" A&P, so ask him about the approved methods. My C has quarter-turn dzus fasteners, and I don't want to talk about having to replace any of them.

Edited April 9, 2019 by Hank

[Shadrach]

Specific location would help. Likely in need of new nut plates (requires riveting) or replacement tinnerman nots. Over size screws create more problems then they solve.

[jaylw314]

22 minutes ago, Hank said:

You can clip in a nut plate of the correct size, or take the lazy way out and use a larger screw. But you'll need a "supervising" A&P, so ask him about the approved methods. My C has quarter-turn dzus fasteners, and I don't want to talk about having to replace any of them.

Replacing non-structural standard fasteners is allowed under preventative maintenance, so technically you don't need a supervising A&P.  On the other hand, trying to squeeze nutplates (one of the more hilarious phrases in aviation) is something best done with knowledge, experience or practice first (or preferably all of the above)...

[RLCarter]

I assume they are machine screws an not sheet metal screws, some are nut plates and some are rivnuts, either way they have to be replaced to correct the problem, both also require the proper tools to replace them. 

[carusoam]

SC,

Now would be a good time to throw in a pic...

Or MS will solve every screw challenge you are going to have for the next five years.  

My M20C didn’t take many screws out of the cowl, except access panels and that only happened annually...

Make sure you have the right screws to match the threads that are there... stainless ones, because they hold water in the top... if there aren’t threads there... something happened to them... 

sheet metal screws... for this application... are probably not the right screw for the application...

If you need to replace the threads... they are the riv-nuts... threads riveted in place... see your mechanic... quickest and lowest cost method....

Great question... just need some more detail...

My M20C was stock 1965...

PP thoughts only, not a mechanic...

Best regards,

-a-

[Guest]

7 hours ago, Supercop0184 said:

What’s the best fix for some of these cowl and avionics access cover screw holes   Right in front of the windshield. that just won’t hold a screw? 64C model. Seems like several of each type are stripped and I’m OCD enough that it’s got to be fixed. 

 

Thanks! 

Most of the cowl screws on the cowl are #8 PK type screwed into Tinnerman clip on nuts, quite easy to replace.  The instrument panel access is a combination of #8 PK screws and AN 526-832R8 screws, most of these are riveted the airframe.

If you can operate a drill and a pop rivet gun you can do this.  You need a #40 bit.  If you don’t have solid rivets and a squeezer,  Cherry rivets are available for holding plate nuts on.

Spruce has everything, search for Tinnerman nuts and CCC-32 Cherry rivets.

Clarence

 

[47U]

I think OP might be talking about this little gem, mounted at a right angle just in front of the windscreen.  On my '63C, it holds the aft row of screws on the avionics access panel and his '64C might be the same.  Might take a call to Dan at LASAR to find it.  As a temp repair, I tapped my four or five stripped 8/32 nutplates out to 10/32 and deferred for phase for a more permanent repair.  If I can find the nutplates.

Tom

[carusoam]

Great pic, Tom!

Thanks for sharing that.

Best regards,

-a-

[Shadrach]

1 hour ago, 47U said:

I think OP might be talking about this little gem, mounted at a right angle just in front of the windscreen.  On my '63C, it holds the aft row of screws on the avionics access panel and his '64C might be the same.  Might take a call to Dan at LASAR to find it.  As a temp repair, I tapped my four or five stripped 8/32 nutplates out to 10/32 and deferred for phase for a more permanent repair.  If I can find the nutplates.

Tom

Thats an easy fix with a rivet squeezer.  Most A&Ps will have one.

[RLCarter]

46 minutes ago, Shadrach said:

Thats an easy fix with a rivet squeezer.  Most A&Ps will have one.

Not an A&P, but I like sheet metal work, my IA gives me little side jobs he doesn’t want to fool withd

[Marauder]

Not an A&P, but I like sheet metal work, my IA gives me little side jobs he doesn’t want to fool withd

Dude! What a toy box. Where can I get one?


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[RLCarter]

1 hour ago, Marauder said:

Dude! What a toy box. Where can I get one?
 

 

lol, I hate paying shipping, so I order stuff that I've had to barrow and use it as fillers to get me to free freight. I still have all the part#'s from Spruce if you really want them, 

[Supercop0184]

7 hours ago, Shadrach said:

Thats an easy fix with a rivet squeezer.  Most A&Ps will have one.

Yes. THOSE!!! Thanks! They are a pain!

[Shadrach]

15 hours ago, Marauder said:

 

Dude! What a toy box. Where can I get one?


Sent from my iPhone using Tapatalk Pro

 

Haven't you spent enough this year?

[Shadrach]

15 hours ago, RLCarter said:

Not an A&P, but I like sheet metal work, my IA gives me little side jobs he doesn’t want to fool withd

Is that a Tatco Squeezer?  Does it have interchangeable yokes? I'm going to need to replace the rear left nut plate on my upper cowl. It is sandwiched between an inner and outer skin so I may be in the market.

[RLCarter]

35 minutes ago, Shadrach said:

Is that a Tatco Squeezer?  Does it have interchangeable yokes? I'm going to need to replace the rear left nut plate on my upper cowl. It is sandwiched between an inner and outer skin so I may be in the market.

ATS Squeezer, but Tatco yokes are supposed to fit. 

[Yetti]

CB solution.    https://m.harborfreight.com/45-piece-threaded-insert-riveter-kit-1210.html?utm_referrer=direct%2Fnot provided

[jaylw314]

2 hours ago, RLCarter said:

ATS Squeezer, but Tatco yokes are supposed to fit. 

If you do any amount of rivet squeezing, you NEED to get the Cleveland Tools hand squeezer.  It's expensive, but you can use the standard yokes used on all the pneumatic tools, so whatever your A&P uses you can just snap those into your hand squeezer.  It's made out of aluminum so it's half the weight, and it has a two-stage mechanism so you have more leverage as you set the rivet further, which means your hands and arms will thank you.

 

[Marauder]

Haven't you spent enough this year?

I am working on the best equipped non-maintenance shop in southeastern PA!


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[Marauder]

Haven't you spent enough this year?

And BTW, is this my wife who hacked into your account. I’ve heard this before.

That reminds me, my Pig Mats are getting delivered today!


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[RLCarter]

6 hours ago, jaylw314 said:

If you do any amount of rivet squeezing, you NEED to get the Cleveland Tools hand squeezer.  It's expensive, but you can use the standard yokes used on all the pneumatic tools, so whatever your A&P uses you can just snap those into your hand squeezer.  It's made out of aluminum so it's half the weight, and it has a two-stage mechanism so you have more leverage as you set the rivet further, which means your hands and arms will thank you.

Well Crap....Anyone wanna buy a slightly used ATS squeezer? Just kid'n, when you only squeeze a dozen rivets or so a month the ATS works really well

[jaylw314]

8 hours ago, RLCarter said:

Well Crap....Anyone wanna buy a slightly used ATS squeezer? Just kid'n, when you only squeeze a dozen rivets or so a month the ATS works really well

It makes squeezing rivets akin to a religious experience, I'm telling you!  

[Yetti]

Ok who wants to help me buy cheap tools.   On the front baffle, the one you can see looking at the prop there is a riveted 3/4' strip that connects to the side baffle with a machine screw.    If I took it off I could use a squeeze, but that would be a pain.    So I would like to buy an assortment of rivets a bucking bar and and rivet gun with a rivet set.   1/8" rivets is what i think we will be putting in for two pieces of .125 alum.

 

And go.   I have money for ebay if needed.  The CB wins

[lamont337]

On 4/9/2019 at 3:01 PM, 47U said:

I think OP might be talking about this little gem, mounted at a right angle just in front of the windscreen.  On my '63C, it holds the aft row of screws on the avionics access panel and his '64C might be the same.  Might take a call to Dan at LASAR to find it.  As a temp repair, I tapped my four or five stripped 8/32 nutplates out to 10/32 and deferred for phase for a more permanent repair.  If I can find the nutplates.

Tom

I described these to Dan about two years ago and he knew exactly what I was talking about. $5 a piece if I remember correctly, removed from a salvage plane.