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Not trying to take away sales from Old Man Emu but grade 5 bolts are the same quality as AN. It's just the tolerances that are'nt as exacting. Most good bolt and nut shops should carry them.

 

 

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Not trying to take away sales from Old Man Emu but grade 5 bolts are the same quality as AN. It's just the tolerances that are'nt as exacting. Most good bolt and nut shops should carry them.

Not being critical, but if the tolerances aren't as exacting, then I'd argue they can't be the same quality, even if the strength is similar. Bolts are cheap, and if the plans call for AN, I'd be wary of using other hardware in something that was going to leave the ground with me in it.

 

rgmwa

 

 

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I'm looking to source a small quantity of AN hardware in Australia. Any advice? Thanks Erik

Erik,

 

The hardware I sell is certified aircraft grade and is traceable back to the manufacturer. Since it's my business to support homebuilders, I put a price on my hardware that I'd be willing to pay if I was in my customers' shoes. I also try to keep postage costs to a minimum and only accept cheques or direct credit as a method of payment.

 

Old Man Emu

 

 

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l get all my AN bolts from US they are made by Airfasco industries and not the cheap Chinese copies

 

l just order two hundred bolts an 100 nuts and with postage was only $67.00.US

 

 

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Despite the Australian dollar being over parity with the US dollar, costs have risen recently because postage rates have gone up. A 5lb flatbox has gone up from $US13.50 to $US16.60 and the 20 lb box had gone up from $35.50 to $66.50. You have to bear in mind these factors when buying hardware. The cost of postage has to be spread over the whole order and therefore the retail price for a particular item can vary throughout the year, depending on the share each item has of the total postage cost. At the same time, Austpost has put up its rates, too. However, I find that Austpost is most frequently cheaper than courier for small weight parcels.

 

If you look at an AN bolt and see the letters AFC, that means that it was made by AirFasCo, so you know the bolt is OK. We can buy from them, too, but with a minimum order of $US200, we can't often use them for restocking. I can restock from a wholesaler in Australia for similar prices to those charged by AFC + postage.

 

However you choose to reduce your hardware costs, don't go near automotive or general hardware retailers. You can't trust the quality for use in aircraft.

 

OME

 

 

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One of the differences between AN and other bolts is that AN have rolled threads and also the root radius of the thread is greater. that means that they will develope more strength. Just the fact that the metals are similar is not enough to make them all the same quality.

 

 

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Okay...okay.....I stand corrected. I have used a few grade 5 bolts in non critical areas but it seems I should stick to the AN stuff for everything else. I should do an inventery of what I need to finish the Nieuport and send you a list Mark.112_im_stupid.gif.235c6602d589883b543a8ad3d313ca3c.gif

 

 

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Erik,The hardware I sell is certified aircraft grade and is traceable back to the manufacturer. Since it's my business to support homebuilders, I put a price on my hardware that I'd be willing to pay if I was in my customers' shoes. I also try to keep postage costs to a minimum and only accept cheques or direct credit as a method of payment.

Old Man Emu

Thanks OME, I'll be in touch.

 

Erik

 

 

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I have used a few grade 5 bolts in non critical areas but it seems I should stick to the AN stuff for everything else.

The plane that you build will be a display of your craftsmanship. You will be putting your heart and soul into the build, so why not use what a craftsman would use? Are adverse comments about your building efforts worth the saving of a few dollars made by using no-name hardware instead of certified stuff? I'm not concerned from where you source your hardware; I just want people to look at your finished project and say, "He went to a lot of effort to make things 'just so' in this build." Nothing detracts from the overall impression of a job than the smallest lack of detail.

 

(If the Grade 5 bolts are holding non critical stuff together, would it be too hard to replace them with the good stuff?)

 

OME

 

 

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so what happens if you keep cutting corners with your build? you end up putting yourself at unnecessary risk. I would stick to the specifications that Aerdrome have provided, at least you know its works.

 

 

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  • 4 weeks later...

Quote " One of the differences between AN and other bolts is that AN have rolled threads" ...............No it's not................... All bolts of any half decent manufacturer have rolled threads. .... Just don't use stainless bolts in high strength applications please.....(Galling issues ect ., )

 

 

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If my memory is correct auto grade 5 are considered satisfactory, for building our stuff. . In a world where even so called aircraft parts are not what they seem as there are a lot of "bogus" parts out there. I would hardly trust stuff you are getting from the hardware stores to hold up a fence. In times past, if you could read GKN or similar on the head they woud be OK. Brands like unbrako etc the same. Everything has changed . The stuff comes from anywhere. Medicines processed food pet food dried milk. Stick to AN from a proper source. You get specified lengths , drilled for split pins, proper nuts. plated. By the way, do not plate any structural parts on your plane unless they are heat treated to remove hydrogen embrittlement at the same time. The part can snap like a carrott. The AN bolts are not that dear and even grade 5 are becoming ridiculously expensive. A loose thread fit will weaken the torque spec of a bolt a large amount. Shear loads depend on fit of the parts too. A loose fit on one bolt shank may pass a lot of load onto another.

 

The local hardware chucked out everything but metric the other day. Nev

 

 

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My last two a/c have had the wings held onto the fuslage by two bolts each. Not much room for redundency- if one breaks there isnt another to take the load like in an airliner.

It's pretty standard to have just two bolts to hold each wing on - Cessna, Pitts (Lower wings). You are going to get other things breaking long before the wing attach bolts will shear.

 

OME

 

 

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It's pretty standard to have just two bolts to hold each wing on - Cessna, Pitts (Lower wings). You are going to get other things breaking long before the wing attach bolts will shear.OME

Out of all the thousands of bolts made, some must be duds. Do they get checked with x-ray or something. When your life depends on one bolt holding, you get critical. Never used to worry until I started snooping around to see how a/c were made. I would design two bolts for every critical fastening.

 

 

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The method used to produce them has a lot to do with their reliability. They are mostly used in a shear situation, and a small bolt will carry a surprisingly high load. Structural reduncancy is rare I would say in most simple designs. Systems redundancy is common in larger aircraft. One place where redundancy should exist is in pitch control capability.. You can't fly a plane without pitch control.

 

Your aircraft inspections should be sufficient to pick up loose rivets cracks etc If you start duplicating everything the plane will get very heavy, but there can be elements of good design put in to the plane that don't add weight. As an example the wing attach pins/bolts on a highwing where the highest loads are compressive, the spar end attach point could butt against a stop as well as the pin. This is done most times. Nev

 

 

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