I damaged a screw securing an inspection cover on the Bonanza. I thought the hard part is identifying the screw type – and then replacing it would be very easy… the Internets surely being full of all kinds of screws!
So, my verdict: it is probably an American #10 diameter screw (= approx. 4.82 mm), 32 TPI (= approx. 0.8 mm thread spacing), 5/8" long (= approx. 15.88 mm), stainless steel, flat head, Phillips drive. Even though my rusty caliper says 4.6 mm diameter and 15.3 mm length, the American standard seems the closest and most probable fit. I somehow doubt Beech had used M4.5 (and the 0.75 mm comb does not fit anyway).
Now the easy part … turned out to be actually very hard! Apparently there is a market for American screws in Poland catering for Harley-Davidson motorcycle lovers… But it seems I can only get Torx head #10-32 screws domestically. Not sure how to google this effectively in German or French… So I thought that since it’s actually easier now to get stuff into EU from the US than from the UK, why not try a worldwide search. Alas! Applying all the specs on Amazon unbelievably yields 1 result (… 100 pcs at $80 … plus $94 shipping!). I also tried Military Fasteners someone here had suggested before . Again, a failure.
I only found a 675 item Beechcraft 33/35/36 screw kit that surely must contain the part I need… but it also looks like not entirely an economical and environmentally friendly way to replace a single screw (and maybe build a stock of five extra, just in case :-)
Any hints?
If you can find the same screw with another drive style (hexagonal or tork of preference) you should do it without doubt.
That Philips style drive is okay for an IKEA cabinet, not for an aircraft. Thus your problem damaging the head.
You would have to change all the screw on that cover, but screws are not something expensive.
Otherwise, your screw seems very standard (at least in countries using the imperial screws) so shouldn’t be too difficult to find, but I doubt you can find to purchase just one.
Otherwise you can also check from suppliers selling screws and bolts for the classic car market as it is common to use imperial on some classic cars. But then it will be mostly with hexagonal drive.
Hope it helps.
Found that after a quick search. Seems it matches
https://www.accu.co.uk/en/imperial-phillips-countersunk-screws/364449-SIK-10-32-5-8-A2
The UK should not be a problem unless the seller is simply illiterate, but I am happy to buy anything and airmail or courier it to anywhere.
rschris wrote:
You would have to change all the screw on that cover, but screws are not something expensive.
Hmm haven’t considered that … Not sure if I feel comfortable replacing all the inspection cover screws on an aeroplane that belongs to someone else… And it seems to me these Phillips drive screws were fitted originally by the factory (looking at that “general Beech screw kit”).
https://www.accu.co.uk/en/imperial-phillips-countersunk-screws/364449-SIK-10-32-5-8-A2
Thank you very much!
In a remote area of the US I’d get them from McMaster Carr link. They supply… ummm…. everything fast but don’t ship to Europe. If you want to order a bag of them and have them shipped to me in the US, I can post them to you. Send me a PM if needed.
The link is for stainless, they have plated screws too here
It’s probably an MS24693-S273 (10-32 thread, 5/8" long, cadmium plated steel, philips head) or a MS24693-C273 (same but stainless steel) and you can buy them from Aircraft Spruce or LAS Aero. Aircraft grade screws like these have a 100 degree angle on the countersink, which is different to ordinary screws.
Raiz wrote:
MS24693-S273 (10-32 thread, 5/8" long, cadmium plated steel, philips head) or a MS24693-C273
Now this is what IT calls a “unique identifier”. Extremely helpful in the Internets age. Now I can find these screws by the millions. Thanks!
@Peter and @Silvaire, I appreciate your offers to help with shipping! Anyway it looks like – given all the hints above – I can now find a supplier that will send me the screws here for a few bucks.
