Bolts and nuts

cnpeters · #1 08-24-2006, 07:18 AM

I am placing an order with Aircraft Spruce, and was wondering if I should order an assortment of AN bolts, screws, nutplates, and so on, to have handy. I know the kits come with the standard hardware to complete, but there are always modifications to be done, too. Thoughts on handy hardware items, fiberglass and resin, etc. to keep in stock?
Thanks,
Carl
RV-9A empennage

Robert M · #2 08-24-2006, 07:33 AM

Quote:

Originally Posted by cnpeters

I am placing an order with Aircraft Spruce, and was wondering if I should order an assortment of AN bolts, screws, nutplates, and so on, to have handy. I know the kits come with the standard hardware to complete, but there are always modifications to be done, too. Thoughts on handy hardware items, fiberglass and resin, etc. to keep in stock?
Thanks,
Carl
RV-9A empennage

Hi guy. I think you are correct in your thoughts about the hardware from Vans. They seem to supply everything. I have been told to use the supplied nuts, bolts and washers for final assembly only. Buy some cheap "hardware" bolts for the trial fittings and such.

You may also want to (as an option) use platenuts in some of the fiberglass tips for access to lighting. check some of the other posts in the forum where they talk about this thing - a search for this should bring results.

As you can see from my signature that I have finished my tail kit but I haven't done my tips yet but I'll have platenuts at the bottom of the rudder for acces to the tail light.

DGlaeser · #3 08-24-2006, 09:54 AM

It depends on whether you intend to do anything different thann the plans. For instance, I'm making my wingtips removable, so I had to get screws and platenuts for that (and have extra pop rivets now). I also made my baggage floors removable - same story.
I also ended up buying some extra snap bushings and adel clamps, but I'm rear mounting my batteries (for an Eggenfeller Subaru) so I have more wires running through the fuselage than Vans anticipated.
Other than that, I've found the Vans hardware to be pretty complete, and being cheap, I've only bought extra stuff when required.
You will definitely need some fiberglass & resin - but I haven't done much of that yet so how much is TBD.
Getting stuff from places like ACS is pretty quick - I do try to wait until I have a 'bunch' of stuff to order to minimize shipping costs. The problem with ordering extra stuff is predicting what you will need, so you don't buy stuff you don't need

thallock · #4 08-24-2006, 11:36 AM

Carl,
Do not buy "cheap hardware nuts and bolts" for your trial fitting. I would not put cheap hardware store parts where AN parts are intended to go. The AN hardware is fairly closely toleranced, the cheap hardware stuff is not. Use the AN hardware that is supplied, or if you are that worried, buy a few extra of all of the common nuts and bolts. Also, as Robert said, it does not hurt to have a few extra platenuts, pop rivets, snap bushings, etc. There's nothing more irritating that to find that you only have 5 10A bolts when you need 6 to complete an assembly. Nothing more dangerous than putting the 5 bolts in, and saying that you will add the 6th when it comes in.

Also, it is an "old wives tale" that you should throw away a nut with a nylon insert once it has been used. As long as the nylon insert is still good, the nut is ok to use. If your A&P told you to toss them once they have been used, then ask yourself who's paying for them. On the other hand, except for the wing bolts, most of the AN nuts and bolts that we use are not that expensive, so if it makes you feel good, then toss them after use--I don't, I won't.

Here's a link to Carroll Smith's book on nuts and fasteners, that dispels some of the old wive's tales. Hard to read every bit of the book, but there is still a lot of good information here. Worth having on your shelf.

http://www.amazon.com/gp/product/087...lance&n=283155

Tracy.

Robert M · #5 08-24-2006, 11:47 AM

Thanks for the info Tracy

Funny thing.... I was under the impression that using cheap bolts was OK because I thought I was getting "good" advice from somone I trusted that was also building an airplane - go figure.

I will use my supplied hardware. If it doesn't hurt the integrity to use it then why not1?!

Sorry about that cnpeters.

Paul Eastham · #6 08-24-2006, 12:35 PM

Hi Carl,
As you progress in the kit, you'll probably modify something somewhere. And of course there may be some nuts and bolts that get scraped up excessively or outright ruined.

However, I found that (once you get to the wing kit, at least) there are generally enough nuts and bolts of the right size, intended for other areas of the plane, so that you can keep building. I just kept a list of "stuff to order" from ACS or Van's and added a few bolts as I used extras. An order per month, building pretty consistently, and I didn't ever have to stop work for want of the right piece of hardware.

What I *did* order extras of were a few types of rivets that I was substituting frequently (AN426AD3-4 in particular), extra-long rivets that can be cut to any size, oops rivets, cotter pins, scotchbrite pads and roloc disks, sharpie pens...no sense in getting stuck over really cheap stuff like that. I did also grab a small selection of nutplates (including floaters and one-lugs), mostly #8 and AN3 -- those definitely came in handy.

Also good to have on hand: 1/8" and 1/16" aluminum angle, in 1 foot sections. .032 sheet and long strips (the latter can be obtained for free, I believe, by ordering "wing bundle trim" from Van's. Maybe the former too if you can figure out the part number of the practice bundle that comes with the emp)

thallock · #7 08-24-2006, 12:39 PM

Robert,

Sorry, I guess I shouldn't have been so adamant about not using HW store parts. To be honest, there are probably not that many instances where an out-of-tolerance bolt is going to get you in trouble. I mean, if the bolt is too big for the hole, most people are not going to go get a hammer and drive it in, so my advice is unwarranted.

I really just wanted to make the point that reusing AN hardware is not really a problem, as some people would have you believe. When test fitting parts, you really should not be final torqueing things, so there should not be a problem with ruining parts.

One thing that I always do is run a screw into all nutplates, either before or after I install them. This is just to make it easier to install screws later. I use the same screw for all of the nutplates, and I do not throw the screw away afterwards. Obviously, this one screw probably gets a little overworked, and maybe it will not be as good as a fresh screw. However, there are no places where the airplane is being held together with a single screw in a nutplate, so I doubt that this is a problem. Of course, if the head gets mucked-up, it needs to be tossed. Also, if you can insert the screw into a nutplate with you fingers, then it is probably hosed, and should be discarded.

However, I would never use a non-AN screw to clean out nutplates. A nutplate has been squeezed just slightly in order to be a reusable fastener (works like a nut with a nylon insert). You do not want to put an oversized screw in it. Also, I don't think it is a good idea to use a tap on a nutplate in order to get a screw to fit easier. I know Van recommends that you do this in a few places, but a tap will remove metal. In my opinion this defeats the purpose of the squeeze on the nutplate, and I would not do this, unless I had a nutplate that was just way out of spec. I have never had a nutplate that is so tight that running a screw in it will not ease it up just a little. BTW, I forgot to mention that I drag the screw in some Bolube first.

Of course, I am not a mechanical engineer, so this is just my opinion. Note, that opinions are like, well, you know, they are worth what you pay for them.

Cheers,
Tracy.

LettersFromFlyoverCountry · #8 08-24-2006, 12:57 PM

I usually order extra washers and nuts and bolts when I make an Aircraft Spruce order. Also cotter pins and castle nuts. Here's why. It's true that Van's supplies everything you need, but not if -- and this assumes you're like me -- you drop nuts onto the workspace floor, where it rolls under that 300 pound refrigerator you meant to throw out one day. Or you decide to mount the ailerons during wing mating and discover that back when you built the things a year ago, you really didn't do such a great job putting, say, the AN 3-14a bolts back where you could find them.

Obviously, YMMV may vary. And I hope it does.

az_gila · #9 08-24-2006, 01:59 PM

Quote:

Originally Posted by thallock

Robert,

Sorry, I guess I shouldn't have been so adamant about not using HW store parts. To be honest, there are probably not that many instances where an out-of-tolerance bolt is going to get you in trouble. I mean, if the bolt is too big for the hole, most people are not going to go get a hammer and drive it in, so my advice is unwarranted.
......

Of course, I am not a mechanical engineer, so this is just my opinion. Note, that opinions are like, well, you know, they are worth what you pay for them.

Cheers,
Tracy.

Actually, the hardware store bolts are more likely to be undersize, and thus may be a good temporary substitute for use in accurate reamed holes... until you come to final assembly with the correct hardware.

Just don't to anything that needs critical alignment with the hardware store bolts in place....

gil in Tucson

robjohnson · #10 08-24-2006, 02:37 PM

Hey Carl -- as you can see, you get a wide variety of answers on topics such as this. Is any one answer the "right" answer -- probably not. Things are so situational that what might work for one person doesn't work for another.

I can tell you that I have ordered extra rivets from Van's -- LP4-4's and LP4-3's (both for leading edge attachment to the spar). I ordered socket head screws for my tanks, and I do subscribe to the 'ol wives tale of only using a bolt once. Yeah, that means I have a bin of bolts that I don't use on the airplane -- big deal. Cheap insurance and gives me and my wife a piece of mind. I can use them on other things that don't fly up in the air. Like everyone else, I try to tally up my needs and place a bulk order to ACS.