Lynn this is not aimed at anyone. It is commentary. It's good time to give a perspective. I've said this before on other posts.
Figuring out the bolts and general hardware is about the easiest task in restoring, refurbishing, assembling a basket case or a case of forgotten where hardware goes.
Most bolts are UNC (coarse). A few are UNF....door hinges as said. They are Carbon steel. Gr 5 is plenty strong. Trim screws are SS. Not many, if any, are AL and I don't know what Cl is.
Hardware is a basic component found all over the truck. If you want to learn a basic skill and enjoy fixup up trucks and all things mechanical, Bolts, Nuts, Washers and screws are easy. You don't have to learn the decimal equivalent like I had to, fractions are OK. Vendors and Stores speak fractions.
The tools and tricks:
1. Buy a tap and die set with hex dies. The set will have a thread gauge. You need the set to chase threads, renew threads, cut the rust and gunk out. I always save and reuse hardware. You don't need a set of "thread chasers".
2.When you see a threaded hole that needs a bolt, use a thread gauge if you can see OK. Have yourself a collection of known bolts and nuts. One of each size normally seen on our trucks. You use as a go/no-go gauge.
A thread gauge, calipers and a few trial bolts and nuts is a cheap kit. Asking folks to tell you a size for this and that is making them do work you can do and should do.
3. For length, it's the calipers. You figure what is called the stack-up. For thru hole conditions it's the thickness of parts, including the nut and washers and a little stick-out. For Blind hole condition, it's depth of threaded hole, plus stack-up, minus clearance at bottom of hole. The calipers are also used for basic diameter of hole or bolt or nut thread.
After a while you get leaned and know threads and sizes by sight. Threads are delineated by no. or nominal diameter, then the pitch/TPI/threads per inch, UN classification, tolerance(accuracy) and gender. I.E. Drawing callout: 4-40 UNC-2B.... .250-20 UNC-2B..... .375-24 UNF-2A. Now we have GD&T to add to that.
Common UNC sizes are 1/4-20. 5/16-18, 3/8-16...then you will also be able to know the hex size by sight many times. Like socket or wrench to use. 7/16, 1/2, 9/16, etc.
It's kind of nice to learn. It makes things faster and easier. No waiting for some answers on the internet. All mechanics, Jr or Sr, know that basic stuff.
When I renew old hardware, which I like to do, I don't media blast them. It takes off some coatings and sometimes turns them gray. I want to maintain that good old "blackened" look of them. So I clean then with gas and a wire brush, then wash and scrub with soap and water, then wire wheel to super new clean, then chase if needed, then blast with brake-kleen. Albeit I live in an area where there is no rust. Metal hardware on the truck does not get old. Once in a while the threads are damaged or rusted beyond rethreading. Flat washers are reusable. Don't reuse a split lock washer if it's flat.
There are many ideas and methods use by members here. They all work and have merit.
For decimal/caliper measuring: screws 2, 4, 6, 8, 10. start with .086 for no. 2 and add .026 each size up. .086, .112, .138, .164
1/4 and up is easy. Just decimal equivalents.
Sheet metal screws are caliper measured and are same nominal sizes as UN. 2, 4, 6, 8, 10, 12. If they have a taper, measure at the head end.
Bottom line, it's not learning a thing to ask what size bolt to use. It's arm chair mechanic'in. Figure it out, make a list and go to the store. Kits are too expensive but if you copy their lists it gives you a ball park location and size for bolts.
Merry Christmas everybody.
