Replicating a Hawker spun rivet joint

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Harvardiv

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What TFF said - That hawker tool is a dead ringer for my stainless brakeline double flare spinning tool. Well, after you cross it with a forged structural C-clamp (actually, have to say "G-cramp" if it is to be properly Bitish, of course) & spin grind the cones for the desired contour.

Point being, for maybe $90 - $150 and some fun time at the lathe, milling machine, with perhaps some spinning on the surface grinder, you can have a dead ringer for the original tool, to form original looking functional connections.

Dunno what your scrounging options are, but sometimes shopping fleamarkets and junk shops are productive for the raw materials.

If the facility exists to make your own dies, it might even be possible to start with one of the low-buck soft metal tube tools from china.
If spending over $30, be sure the tool is eccentric/spinning type, and was designed to include stainless brake lines.

smt
Rather than doing all that, why not use the method ccf used and replace the tube rivets with solid rivets?
 

Aviacs

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Rather than doing all that, why not use the method ccf used and replace the tube rivets with solid rivets?
Might be your approach, might be my approach for my own project.
The man asked how to do it.
I spent some portion of my professional life helping people do the (mostly simple) things other people told them should not be done; often for historical reasons. I truly have no investment in what method is chosen or why. But if someone wanted to do it as original, it is accessible. & no doubt expensive in either time, or money. :)

smt
 

Harvardiv

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Might be your approach, might be my approach for my own project.
The man asked how to do it.
I spent some portion of my professional life helping people do the (mostly simple) things other people told them should not be done; often for historical reasons. I truly have no investment in what method is chosen or why. But if someone wanted to do it as original, it is accessible. & no doubt expensive in either time, or money. :)

smt
I see, when one works on a British aircraft, I think at some point they have to decide on which battles to fight. Lol Do you have a link for your double pipe flaring tool? My idea is to use an alligator riveter with a cone for both of the teeth and do it that way. However the question comes up how do we know how much strength such techniques have? So using a solid rivet at least gives you a known tensile and shear strength.
 

Aviacs

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Do you have a link for your double pipe flaring tool?
That was eccentric double flare tool.
Double flare feature not needed for the rivets; however the simple flare tools are often not eccentric spinner type which is desired.

My notion is to miscegenate the screw and eccentric needle bearing cone from one of these:
1638054202934.png

with one of these heavy I-beam clamps:

1638054292284.png

& spin grind the forming cone to necessary shape, make tail end anvil & spin to shape on a surface or T & C grinder as well.

Mine is a Rigid, however these tools are available in a range of prices depending on source, including "import", or surplus or fleamarkets, etc. The clamp body could simply be cut out of, say 1-1/4" plate or whatever will accommodate (thick enough) the given screw from the donor.

Depending on rivet size, the cheap spinners from china for soft metals might be contrived to work with a suitable shop made or shaped & hardened cone (I don't know). The essential feature is that it is eccentric, and spin-forms the shape, not just compress it. (Though simple compression might or might not be adequate)

Making the tool does not seem inaccessible nor like it needs be particularly expensive.
However, there are a lot of ferules, crush tubes, and hollow rivets to be made.....
Along with a bit of engineering as you mention.

smt
 
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Tiger Tim

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why not use the method ccf used and replace the tube rivets with solid rivets?
CCF? As in Canadian Car and Foundry? I didn’t realize they made them that significantly different from Hawker. I mean, apart from the slightly different engine and the prop that had a hub too big to fit a spinner.
 

Harvardiv

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CCF? As in Canadian Car and Foundry? I didn’t realize they made them that significantly different from Hawker. I mean, apart from the slightly different engine and the prop that had a hub too big to fit a spinner.
I didnt either until I talked to 2 Canadians who rebuilt 2 of them.
 

Fiberglassworker

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The tubular rivet with flared or spun heading was in common use in Germany and the UK in the construction of light aircraft and sailplanes, in the 1930's. up to the present day.
In Workshop Practice an updated translation of "Werkstattpraxis fur den Bau von Gleit - Segelflugzeugen." from the 1930's on page 166. there are 4 pages covering the installation of these rivets.
This book can be obtained from the Vintage Sailplane association Vintage Sailplane Association .org . It should also be noted that some grommet installation tools have a contour that is very similar to the formed ,head of a tubular rivet
 

Harvardiv

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The tubular rivet with flared or spun heading was in common use in Germany and the UK in the construction of light aircraft and sailplanes, in the 1930's. up to the present day.
In Workshop Practice an updated translation of "Werkstattpraxis fur den Bau von Gleit - Segelflugzeugen." from the 1930's on page 166. there are 4 pages covering the installation of these rivets.
This book can be obtained from the Vintage Sailplane association Vintage Sailplane Association .org . It should also be noted that some grommet installation tools have a contour that is very similar to the formed ,head of a tubular rivet
Thanks for this info!
 

Harvardiv

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brake pad brads and lawn chairs have the same but simpler construction...
inner tube prevents crushing, ferules for sheer loads and the hollow brad holds it all together
Yes and jewelers also create these rivets from tubes and a round punchwhich pushes the edges outward.
 

Harvardiv

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That was eccentric double flare tool.
Double flare feature not needed for the rivets; however the simple flare tools are often not eccentric spinner type which is desired.

My notion is to miscegenate the screw and eccentric needle bearing cone from one of these:
View attachment 118456

with one of these heavy I-beam clamps:

View attachment 118457

& spin grind the forming cone to necessary shape, make tail end anvil & spin to shape on a surface or T & C grinder as well.

Mine is a Rigid, however these tools are available in a range of prices depending on source, including "import", or surplus or fleamarkets, etc. The clamp body could simply be cut out of, say 1-1/4" plate or whatever will accommodate (thick enough) the given screw from the donor.

Depending on rivet size, the cheap spinners from china for soft metals might be contrived to work with a suitable shop made or shaped & hardened cone (I don't know). The essential feature is that it is eccentric, and spin-forms the shape, not just compress it. (Though simple compression might or might not be adequate)

Making the tool does not seem inaccessible nor like it needs be particularly expensive.
However, there are a lot of ferules, crush tubes, and hollow rivets to be made.....
Along with a bit of engineering as you mention.



smt
Do you mean like this?
 

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Aviacs

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Do you mean like this?
Yes, now you are catching up! :)

The OP indicated that such tools were unobtanium and likely expensive:

....had an idea that i think will let me make the spun rivets without the complicated and rare tool that Hawker (and now Retrotec) used
His sticking point for the original method of construction seemed to be the lack of a suitable installation tool. Looking at the sketches, for several reasons, the original parts seem simpler (& more reliably secure in shear) than the alternate method he proposed. IOW, from my biased stand point, making the rivet components as original seems simpler (probably cheaper) and the installation tool does not look insurmountable.

Since a lot of what i have done over the years includes making effective one-off specialty tools, (& short run, manual production of parts like the rivet components) i posted the proposal for relatively cheap, accessible options to re-create the original tool if one cannot be found, or if it costs significantly more than, say, $250. A person with good local resources and some simple machine tools could recreate it for less than $100, albeit at some cost in time, more or less based on existing skills.

Again, I really don't care how anyone does their project.
As has been pointed out by others, there may be simpler, less costly in parts, solutions.
But when someone says "....I could do it right if only i had the right tool..." my mental gears kick in.
It is a sickness.

smt
 

Riggerrob

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The offset required to spin a rivet-setting tool reminds me of a fancy lathe in our engine over-haul department (Coast Mountain Bus Company. It just works from the original center when turning crankshafts where they meet main bearings. But the entire crankshaft can be offset by a few millimeters when machining where piston rods attach.
Bottom line, any of the better-equipped engine over-haul shops should have that type of lathe.
 

Harvardiv

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"But when someone says "....I could do it right if only i had the right tool..." my mental gears kick in.
It is a sickness."

Not implying that, but rather an alternative which is original to CCF.

Why does this tool need to spin? I must be missing something. I would think that a pull down cone would be enough.. Another question, anyone know what the weird shapes for the dies are for this tool, which I attached earlier? Thanks.
 

cvairwerks

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Orbital riveting produces a smooth shop head with less chance of cracking vs standard riveting methods. If you look a tubular rivet that was set via standard methods, you typically see the head split a number of times. While it installs faster, it has much less strength than if done with orbital setting.

Orbital uses slow and even stretching of the tube to roll and set it.
 

Aviacs

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anyone know what the weird shapes for the dies are for this tool,
They are a function of the offset. Since the tool orbits while creating a volute type form (as opposed to straight taper), they will be a slightly different shape, and smaller, small-diameter than the finished form in the hollow rivet.

If the eccentric form is axial, the form of the punch will be the same, just reduced initial diameter, tapering toward the full form as the punch fully seats.

If the form is advanced on a skew, it may be slightly different shape.

smt
 

Harvardiv

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Ok, got it, I am not sure the device in the image I showed earlier does that, perhaps it is ratcheting instead? BTW, Other organizations rebuilding Hurricanes use a rivet gun with a special bucking bar and head to install tube rivets. (Of course anything I have mentioned here is hearsay and subject to verification by anyone reading).
 

cvairwerks

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That’s why I suggested getting in touch with the guys that did the Demon restoration down under. They redid every joint on the fuselage with correct tubular rivets.
 
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