Panther Builders, ever wonder why there is no AN3-8 or AN3-9 bolts or what is the difference between an AN365 nut and an MS21044 nut?
In the new builders manual a hardware reference guide was added that answers these questions and more. The last section contains torque specs, cross references and tables for the most common hardware used on the Panther. It is by no means a complete listing of all the mil-spec hardware as at last estimate, there are approximately 55,000 specifications. To make it easier to find the hardware we limited it to the 100 or so most common hardware items used on the Panther. The list is broken up into sections for nuts, bolts, screws, rivets, etc.
The title for each item contains all the specs that item has been listed under in years past. The coverage of the part number includes material, size and finish codes. Also included is a table of specifications and cross references for the most common dash numbers.
So, check out the section in the builders manual if you have a hardware question. Remember, the builders manual is for registered Panther builders and requires a log-in. If you haven't done so already check it out.
This link is for a video of how to register/login to the manual.
http://support.flywithspa.com/solution/ ... ers-manual
If you can't find the information you need on the hardware, another good source is
http://www.everyspec.com. They have many if not all the specs, and best of all, it is free.
In answer to the first question, the AN3-20 series of bolts have their overall length measured in 1/8" increments. If the dash number is a single digit, the bolt is that number of 1/8" long+ 1/32" for extra lead in thread. So AN3-4 is 4/8" or 1/2" long + 1/32". If there is 2 digit dash number, the first digit is the number of whole inches, and the second dash number is the number of 1/8" increments. So, an AN3-10 is 1 inch and 0/8" long + the extra 1/32". The AN3 and AN4 diameters follow exactly this rule, the AN5 and higher bolts follow the same basic format, but have slightly longer lengths for more lead in threads. Who needs the $10 AN bolt gauge when you have this knowledge. (In case you didn't figure it out, there is no -8 or -9 because they would of been 8/8" or 9/8" long per the rule above, which is an AN3-10 and AN3-11 respectively.) If you hadn't heard this rule before, don't worry, their are many professionals in the industry that don't know it either. You can impress your friends, it is also been used as a trivia question asked to gauge your knowledge of the specs.
The second question, AN365 and MS21044N series of nylon lock nuts are identical, the MS21044N number is the newest specification, the AN365 spec was canceled in the late 1960s. One popular aircraft hardware supplier only lists the AN365 on their website, but ships them in bags marked MS21044N. Most other vendors lists both numbers in their catalog. In the manual, we try to call out the newest specification, as that is what specification the hardware is made to and shipped as from the majority of vendors.
Don't forget the torque specs in this section. It is an excerpt from the FAA AC-43.13-1B and covers rules for torque and the common torque values. Torque values are listed by the bolt diameter and type of nut used, as you are supposed to torque the nut whenever possible.