SonexBuilders.net

Hi All

Can anyone tell me the thread type for the screws holding the two circular inspection panels under the wings? Mine are rotten and I fancy some stainless replacements. I think the nut plates were part of the kit so they'll be an 'American' thread, meaning Ebay rather than a hardware store over here in Blighty.

Cheers

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I just used #6 sheet metal machine screws. If the hole gets enlarged then #8. Unless there is a nutplate, no specific thread type is really necessary. If there are nutplates someone must have added them (they weren't part of my plans anyway), and it would be hard for us to tell what thread they are.

Thanks Ryan
There is a nut plate and it looked from the plans like they were part of a sub-kit, hence the question. They look similar to M4 but I'm sure will be an imperial size.
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Hi Ad. If they look like 4mm they are probably 8-32.

What you need should be on this page somewhere.
https://www.aircraftspruce.com/pages/ha ... /an526.php

You can go to the hardware store and buy a couple screws to try. if they are standard nut plates they will be 6-32 8-32 or 10 32(3/16). I put in nut plates for all my inspection panels and used 8-32 size. The Ace hardware near my airport has these in stainless so I bought them there.

Thanks both.
I'm in the UK so buying 'american' hardware is mail order, hence trying to figure out the right sizes. I'll start with 8-32 as a best guess and measure the screws at the weekend if I'm wrong!

Cheers
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Hi Ad

What are you building in the UK?

Tell me which size and head of screws you need and I will look in my stock.

Cheers
Carlos
Portugal

Sheet metal machine screws...….???

There are "machine screws" and then there are "sheet metal screws"...….it's either one or the other.

Machine screw require a plate nut (anchor nut) like a K1000-8 for a #8 machine screw (8-32 thread)

A sheet metal screw requires NO plate nut but requires the right size hole (smaller) for the #8 screw to get a grip.

On my Onex all the inspection covers were designated #6 sheet metal screws. I discarded them and installed K1000-8 nut plates and #8 machine screws for all inspection covers.
I don't trust sheet metal screw in an airplane in the long term.

Hope this helps...………

Gordon...….Hummel 2400.....Onex

Has anyone tried Pem nuts instead of nut plates. Some of them will work on thin aluminum.

Carlos Trigo wrote:Hi Ad

What are you building in the UK?

Tell me which size and head of screws you need and I will look in my stock.

Cheers
Carlos
Portugal

Hi Carlos
I'm not building but I have a Jab3300 A model Sonex based at Henstridge in Dorset.

Thanks for the offer; I should be able to order what I need., it's just a case of figuring out which size they are.

Where are you in Portugal?
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