HOW IT WORKS: Aircraft Flush Riveting

for possible projection from the outer surface of the airplane everything that would induce turbulence with its attendant drag must be reduced to a minimum the use of a rivet whose head is flush with the surface being riveted eliminates the drag of the ordinary rivet head and thus aids in accomplishing our higher speeds the choice of method to be used in flush riveting is based on the thickness of the sheet next to the manufactured head let's assume we're driving a rivet 1/8 inch in diameter with a 100 degree counter sunk head probably the best production method involves sheets of 40,000 thickness or greater we start with the assembly of the sheets drilling the correct sized hole for the given rivet we're using a 1/8 inch rivet so we drill a number 30 hole then countersink using a special countersinking tool with a 2 flute cutter and with a 100 degree cutting angle and number 30 pilot unless specific approval has been obtained from the stress engineer the countersinking should not go through the first sheet if sheets are properly clamped during countersinking it is not necessary to disassemble them for borrowing which is a costly operation next we insert the rivet the length of which has been determined by adding 1 and 1/2 times the diameter of the rivet to the grip the grip as shown here in white is equal to the total thickness of the material being riveted a vibrating type air gun with the flush rivets set and a regular bucking bar may be used ordinary riveting technique will do for driving of this type rivet the finished rivet should have a formed head 1 in 1/3 times the diameter of the and about one half the diameter hi the flesh nosov the rivet as determined by aerodynamics must run in the neighborhood of plus or minus mm we have just demonstrated the countersink method of riveting this is a method used when both sheets are over 40,000 s in thickness structural requirements make it necessary to dimple the sheet next to the man affected head if this sheet is under 40 thousandths and thickness this double dimple method is used for flush riveting thin sheets here again we start with a number 30 hole and follow this with insertion of the rivet the length of the rivet is again the thickness of the material plus 1 and 1/2 times the rivets diameter the driver uses a standard flush rivets set the bucer uses a special dimpling set that has been adjusted by the tool Department to give the correct angle and depth of the double using the rivet as a punch we dimple the two sheets together into the dimpling set the special dimpling set is removed the driver retains the standard flush driving set the work then proceeds with the Bucer using an ordinary bucking bar driving this type of rivet requires greater skill than was required in the previous method any clinching our offset of the rivet will cause the dimpled edge to crack the rivet must be driven straight we have just shown double dimple method of riveting this is one of the methods used when both sheets total 40 thousandths or less in thickness a third method used for riveting of slightly heavier gauges than in the last method involves a separate dumpling of the sheets again we start by drilling our number 30 hole the sheets are then disassembled and machined dimples separately on the squeezer note the angle of the dimpling tools the dimpling punch for the top sheet has an angle of 100 degrees the same as the rivet head the dimpling die has an angle of 110 degrees the dumpling punch for the bottom sheet is also 110 degrees to correspond with the top sheet and the dimpling die is 120 degrees this difference is necessary in order to get a good nesting of parts upon completion of the dumpling operation the parts are reassembled sheet metal riveting clamps are used to hold the parts together until riveting is completed the rivet is inserted and from here on the work proceeds using a regular flush riveting set and the ordinary bucking bar driving this type of rivet requires the same skill on the part of the operator as in the former dimpled method it is very important that the rivet be driven straight we have just illustrated the pre-dental method of riveting the sheets were taken apart and machined dimples separately on the squeezer this is a method used when the sheets are too heavy for the double dimple process for sheet gauges for the top sheet is too thin to countersink and the bottom sheet too thick to temple we must use a combination of pre dimpling and countersinking the top sheet being under 40 thousandths must be dumb old the bottom sheet being over 40 thousands will be countersunk again we start by drilling and number 30 whole sheets are disassembled and the upper sheet is machine dimpled using special dumpling tools on a squeezer type machine the bottom sheet is countersunk using the special countersinking tool the angles of the dapple and countersink are very important the angle of the dimple next to the rivet must be 100 degrees because the rivet head is 100 degrees the angle on the opposite side of the sheet is 110 degrees the angle of the countersink is also 110 degrees parts are reassembled using sheet metal clamps rivet is inserted this is followed by driving the rivet using a standard flush driving set and bucking bar this riveting technique is fairly simple because there is no lip on the under sheet to cause cracking or failure from clencher rivets we have just demonstrated the combined countersink & dimple method of flush riveting this combination is used in cases where the sheet next to the rivets manufactured head is too thin to be countersunk and the bottom sheet is too thick to be dumped old now let's review the four methods of flush riveting just demonstrated countersinking used when the top sheet is 40 thousands thickness or greater the flush nests of the rivet is obtained by setting it into a hole countersunk by special to double dimpling use when the total thickness of the sheets being riveted is 40 thousandths or less in this method the flush this of the rivet is obtained by using the rivet itself as the punch to form the dimple pre dimpling used when the top sheet is 40 thousands or less and the total thick of both sheets is over 40,000 and under 90,000 s the flesh nosov the rivet is obtained by setting it into a dimple form mechanically on a squeezer combination counter sinking and dimpling used when the top sheet is too thin to countersink and the bottom sheet is too thick to dimple the top sheet is dumped 'old and the bottom sheet is countersunk the result obtained by each of these different methods is the same the head of the rivet is flush with the surface so that the turbulence or drag is held to a minimum you with the ever-increasing demand for greater speeds and aircraft it has been necessary to remove every possible projection from the outer surface of the airplane everything that would induce turbulence with its attendant drag must be reduced to a minimum the use of a rivet whose head is flush with the surface being riveted eliminates the drag of the ordinary rivet head and thus aids and

Channel: DOCUMENTARY TUBE

Views: 2,085,261

Rating: 4.8326092 out of 5

Keywords: make, machining, build, plane, aviation, engineering, mechanical

Id: IDbTUt3OG9s

Length: 10min 36sec (636 seconds)

Published: Wed Oct 22 2014

Reddit Comments

[u/HAIL_TO_THE_KING_BB]

Now I wait for aircraft rivets to come up in a casual conversation.

[u/Dadanoosh]

I do this for a living. This video has some ancient tools, and hand countersinking rivets can suck my nuts. The absolute best way to do this so your rivets don't end up all fucked up is with a stop-countersink and a drill press. Except most parts don't fit in a drill press. So you have to hand countersink. Fuck.

[u/slingerpanty]

I wish this video was more riveting.

[u/[deleted]]

I used to work on airplanes, but I've never riveted like this. We had these pre-made rivets that forced a ball at the end of a stick into a sleeve.

Here they are.

You would just use a gun to pull on the stick and diagonal cutters to snip it off. I'm sure sheet metal guys probably riveted the old fashioned way.

[u/FFG36]

I not only found the topic interesting, I absolutely LOVE movies like this that were made in the 1940s. Instructional videos of the era really are great.

[u/[deleted]]

Show me your double dimples!

[u/5k3k73k]

Someone should invent a thixotropic fastening fluid. Until activated it would be hard and inert so it could be safely painted at fasten points on the mating surfaces any time before assembly (or painted on the entire surface making any area a potential fastening point). During final production the mating surfaces are held together as an ultrasonic transducer ("sonic screwdriver") applies a specific high energy frequency (one engineered to never occur naturally) to lower the viscosity of the fastening fluid and allow the fluid to flow between the two surfaces. Once the surfaces are bound the transducer is removed and the fluid returns to its normal high viscosity/semi-solid state.

Assuming such a fluid could be engineered there would be many benefits:

• Faster production (no pre drilling)
• Cheaper production (fewer parts)
• Greater structural integrity (no holes and any number, shape, or size of fastening points)
• The process can be reversed for easy disassembly (maintenance, upgrades, replacement, etc)

[u/turbojugend79]

I watched way too many minutes of that.

[u/crasfpv]

Great to learn this but i fall in sleep when review stared.