Solid Rivet shop head size criteria

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BBerson

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I don't have that much problem myself with years of experience. I am concerned that the solid rivets are not the ideal choice for the next generation kit builders for a bunch of reasons, including noise. Is it realistic? Or is blind rivets the choice for the modern aviation fastener? Or bolts like the BD-4.
 

Angusnofangus

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I don't have that much problem myself with years of experience. I am concerned that the solid rivets are not the ideal choice for the next generation kit builders for a bunch of reasons, including noise. Is it realistic? Or is blind rivets the choice for the modern aviation fastener? Or bolts like the BD-4.
I think some people might think that it's too steep of a learning curve to use solid rivets, but I don't feel that it is really that bad. I had my grandson driving rivets when he was six, and after the first few, he got right into it. Noise could certainly be a factor, especially if one is building in their garage and the neighbours are close. Personally, I would use solid rivets even if blinds are called for, but that's me. I'm more than comfortable driving rivets.
 

N804RV

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I don't have that much problem myself with years of experience. I am concerned that the solid rivets are not the ideal choice for the next generation kit builders for a bunch of reasons, including noise. Is it realistic? Or is blind rivets the choice for the modern aviation fastener? Or bolts like the BD-4.
When strength and weight and cost are considerations for aluminum semi-monocoque construction, solid rivets will always be the fastener of choice for the majority of the structure.
 

rv7charlie

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If you're designing (and you know what your'e doing), you can design for anything you want as long as it's safe. But if you're building a kit, or even building from plans, it's likely very unwise to change the fastening method specified by the designer. Extreme example: the homebuilt that had a wing failure & crashed at OSH a few decades ago. NTSB found that the outer wing attach areas had aluminum rivets instead of the specified bolts. Even replacing rivets with bolts can be problematic in some specific circumstances. Replacing bucked with pulled is almost never wise if the structure is designed for bucked; pulled rivets (even Cherry Max) may have the same clamping force but do not expand to fill the holes. The attached components can then move in shear (same potential issue using bolts to replace rivets).

Charlie
 

BBerson

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Right. The designer in chief can write the criteria.
My logic is this: the handbook says to use rivets of same alloy or softer than my 6061 sheet. Since 6061 rivets are not readily available, it's reasonable to hammer the typical hard 2117-t4 rivet somewhat less to avoid sheet damage.
As Mad Mac said, fatigue life requires hole filling. So I will drill out a few samples to see if the hole filling is correct.
The guy at the rivet store suggested 1100F soft rivets. My chart shows 1100F are 1/3 the shear strength of 2117T3. So I didn't find his advice appropriate. In the past I had found a loose aileron control bracket on a J4 Cub. The rebuilder had used soft 1100F rivets.
 
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Dan Thomas

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Air hammers are not the same as rivet guns, you don't have the control that the teasing trigger of a proper rivet gun has. I have a spare 3X gun that I would let you have cheap. PM me if interested.
That there. I tried the muffler gun, too. A waste of time and money. AD rivets harden as they are bucked, so they have to be hit hard for a few bangs, not weakly for lots of bangs, or you'll just get frustrated with the results and maybe make a mess. I have a 4X gun, and in one place the guy I worked with had a 7X that was often very handy for larger rivets.
AD rivets aren't supposed to age-harden, but they do, slowly. Buy them from a supplier that sells lots of them so they're fresher. Store them in a freezer to keep them fresh. Warm them to room temp before using.
 

BBerson

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AD rivets aren't supposed to age-harden, but they do, slowly. Buy them from a supplier that sells lots of them so they're fresher. Store them in a freezer to keep them fresh. Warm them to room temp before using.
Not very practical. That's why I am looking at all ideas..
I tried various ways of heat treating them. Largely impractical for home experimenters.
 

TFF

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The real choice is make sure the thickness needing riveting match off the shelf rivets
to a T or spend the time cutting the rivets down. Just a little long for me never works. I also find, the more pressure you can put on the rivet head before and during the job, the better of things look. For me once I can’t put pressure on it, it starts going down hill.
 

BBerson

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A belt sander will make a rivet shorter. Take off 1/8" in about 5 seconds and the rivet will get very hot and somewhat softer. A cheap wire crimper has holes for bolt cutting. Works well to shear rivets. Another hole can be drilled in the tool for 1/8" rivets.
 

Angusnofangus

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Right. The designer in chief can write the criteria.
My logic is this: the handbook says to use rivets of same alloy or softer than my 6061 sheet. Since 6061 rivets are not readily available, it's reasonable to hammer the typical hard 2117-t4 rivet somewhat less to avoid sheet damage.
As Mad Mac said, fatigue life requires hole filling. So I will drill out a few samples to see if the hole filling is correct.
The guy at the rivet store suggested 1100F soft rivets. My chart shows 1100F are 1/3 the shear strength of 2117T3. So I didn't find his advice appropriate. In the past I had found a loose aileron control bracket on a J4 Cub. The rebuilder had used soft 1100F rivets.
Those 1100 rivets are 'A' rivets, 2117's are 'AD' s, 'A' rivets are very soft and never used structurally. RV7 Charlie's example of someone substituting rivets for bolts is a huge no-no. You can NEVER substitute a weaker fastener for a stronger one. That said, Cherry-Max can be used in place of solids, but not on a one-to-one basis. And actually, Cherry-Max DO expand and can fill a hole that is slightly bigger. The recommended hole size for nominal 1/8 is .129-.132, this for a rivet that is .125 in diameter.
 

proppastie

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1/2 dia min. height shop head. (I will try to find ref.) usually from 1 dia protrude before driving. Link a little different and more detailed.
 
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BBerson

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Those 1100 are "A" rivets, 2117's are 'AD' s, 'A' rivets are very soft and never used structurally. RV7 Charlie's example of someone substituting rivets for bolts is a huge no-no. You can NEVER substitute a weaker fastener for a stronger one
The soft "A" rivets are not used on certificated aircraft. But could be used on an ultralight if the designer used three sizes bigger than that "AD". The AD rivets are three times stonger. The 3/16" "A" rivets are widely used for structural truck panels.
 

gtae07

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Right. The designer in chief can write the criteria.
My logic is this: the handbook says to use rivets of same alloy or softer than my 6061 sheet. Since 6061 rivets are not readily available, it's reasonable to hammer the typical hard 2117-t4 rivet somewhat less to avoid sheet damage.
As Mad Mac said, fatigue life requires hole filling. So I will drill out a few samples to see if the hole filling is correct.
The guy at the rivet store suggested 1100F soft rivets. My chart shows 1100F are 1/3 the shear strength of 2117T3. So I didn't find his advice appropriate. In the past I had found a loose aileron control bracket on a J4 Cub. The rebuilder had used soft 1100F rivets.
I don’t see any reason to treat AD rivets in 6061 any different than you do in 2024. Nobody else does, and that includes on transport-category jets (yes, they use 6061 on occasion). Just buy some rivet head gauges, set them, check them, and build on.
 

Angusnofangus

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1/2 dia min. height shop head. (I will try to find ref.) usually from 1 dia protrude before driving. Link a little different and more detailed.
The general standard for aluminum rivets is 1 1/2d protruding through the material stack-up. You could get an acceptable shop head size with 1 1/4d but not with 1d.
 

Angusnofangus

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The soft "A" rivets are not used on certificated aircraft. But could be used on an ultralight if the designer used three sizes bigger than that "AD". The AD rivets are three times stonger. The 3/16" "A" rivets are widely used for structural truck panels.
'A' rivets do have some use on certificated aircraft, mainly in thin fairings, but never in anything structural. It would make no sense to use a larger (3/16) A rivet if a 1/8 AD is the same strength.
 

BBerson

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'A' rivets do have some use on certificated aircraft, mainly in thin fairings, but never in anything structural. It would make no sense to use a larger (3/16) A rivet if a 1/8 AD is the same strength.
Actually, the Airframe Handbook recommends 1100 "A" rivets for parts fabricated from 1100 and 3003 alloys.
It doesn't mention structural or not. That's up to the designer.
Using a hard rivet in soft metal doesn't get enough bearing area.
 

Angusnofangus

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Actually, the Airframe Handbook recommends 1100 "A" rivets for parts fabricated from 1100 and 3003 alloys.
It doesn't mention structural or not. That's up to the designer.
That makes sense, as driving AD's in 1100 or 3003 will give you big divots around each rivet head. I'm sure you won't find either alloy used structurally in any certificated airplane. No designer worth his salt would use those alloys as structure in a homebuilt either.
 
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