Idea for T & G construction assist tool

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Grumpy Cynic
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Why not just pick a single gusset thickness and live with the minuscule weight penalty?
With the one piece, non-adjustable version, make it for the thinnest gusset and then just wrap a sheet(s) of paper or aluminum partially around the tube for thicker gussets?.......Or tape the shim under the shoe if designed for the thickest gusset?
 

radfordc

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On my V2.0 tool I didn't add any allowance for the gusset thickness. Seems to work just fine.
 

Aerowerx

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With the one piece, non-adjustable version, make it for the thinnest gusset and then just wrap a sheet(s) of paper or aluminum partially around the tube for thicker gussets?.......Or tape the shim under the shoe if designed for the thickest gusset?
Shouldn't be the other way around? Make it for the thickest gusset and shim with paper/plastic/aluminum for the thinner?

And how much difference in weight would it make using all 0.040, instead of a mix of 0.025, 0.032, and 0.040??
{Edited] Corrected second 'thicker' to 'thinner'
 
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radfordc

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Here's an idea... Somebody mill these out of micarta or nylon and offer them through Aircraft Spruce, with the proceeds going toward HBA operation costs, server space, etc. Or offer them through Airdrome Aircraft.
Having worked with Robert Baslee I can't imagine him using a tool like this. Doesn't fit his "good enough is good enough" approach to building. I've never seen a cleco in his shop.
 

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Grumpy Cynic
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This thread consumed some of my early morning lay there and think about the day time. It occurred to me that this may be the only thread here on HBA where 'design by committee" has actually produced hardware.........usable hardware too :beer:

But we can still do better.

I have in mind a third generation version taking advantage of many of the good ideas already presented. Unfortunately for this thread, but fortunately for me, the weather here today and tomorrow is good. That means I have other projects that have priority........

No adjustment, single hand use, 3D printable/OTS hardware store parts.
 

FritzW

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Perhaps not, but the error is somewhere in the decimal points, which for pulled rivets is meaningless.
The error would be a fraction of the typical error you'd get hand drilling the same hole. Nobody holds a hand drill at 90.000 degrees to the work.
 
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Grumpy Cynic
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Nobody holds a hand drill at 90.000 degrees to the work.
Then your technique is poor. :p

I can guarantee that nearly 85.456% of my hand drilled holes are at 90 degrees to the work surface..........
at some point in the process..... but probably not in the X and Y axis at the same time.... or for very long.:oops:

Perpendicular!? It might have happened a few times over the last couple of decades. :(
 

Victor Bravo

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Eliminating those small errors is part of why this tool is useful. I'm guessing that a little better hole quality will add a little more service lifespan to the riveted joint. So if 89.5 degrees and v ery slight ovaling of the holes is "good enough", then 90 degrees and a better set of holes with no oval is probably a worthwhile thing. Especially when it was very easy to achieve with this little shop aid.

But... then when you consider that a fairly small Y axis offset in the gusset hole location will also put the hole off of the center line of the tube, and thus no longer at the contact point between the tube and the gusset... now you have a small amount of unsupported gap between the tube and the gusset.

I'm guessing that even a small gap between the tube and gusset will result in a shorter service life of the joint, or reduce the amount of cyclic load the joint can take before failure. A gap between the tube and the gusset means the rivet shank sees additional bending loads instead of just straight tension or shear???

Because of then umber of Graham Lee / Baslee airplanes out there flying safely, I'm guessing that there is plenty of extra load-bearing capacity and service life designed into the joints, even with mediocre workmanship. But if doing it better and safer and longer-lasting becomes easy and quick with a $5 shop aid tool, that's a huge winner to me.

The other aspect of this tool's usefulness, for the slovenly and lazy builder like me, is that it will save a lot of measuring, marking, and center-punching time over the course of building a fuselage using the T&G method.
 

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Grumpy Cynic
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Version Delta. Still multi part but simpler that my last. Use rubber bands on the peg and 'third hand'.
Put a slight kink in the metal spring near the shoe so the shoe always lays flat on the gusset.
Ver delta.JPG
Zip file is the SW file. Use as desired..........It is kind of an extemporaneous mess.

Edit: Won't modify the files now but a small 'shelf' 3D printed about 1/8" thick just under the alignment cleco would serve double duty in keeping the shoe down as well as on the intended rivet spacing.
 

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Grumpy Cynic
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What are the bolts for?

I like the mousetrap spring, but there may be a better idea for that aspect.
The gray strap is steel or aluminum for spring tension. Removes the need to adjust for different thickness gussets or different diameter tubes. Bolts hold it to the 3D printed parts. Original thought was to re-purpose an off the shelf putty knife blade, but if you have material for gussets you have material for the blade.

A simpler, better integrated, spring clamp would be an improvement.
 

Victor Bravo

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With sincerest possible respects, the business card(s) spacers (when necessary) would eliminate all of the bolts and the steel strap.

One machined or printed part, with a V-groove in the middle and a threaded hole for a drill bushing on each end.

One end has the Cleco-abutting recess (to locate Rivet Holes 2 through 4) and the other end has the bushing for Rivet Hole #1.

The bigger problem, to me, is that it may require additional complexity and parts count to grip or pinch this tool in place on the tube, so you can use both of your hands to do other things. That would justify additional parts. The mousetrap spring is OK, but it may not apply enough clamping force over a large enough area, AND it cannot be installed with the tube sitting in contact with the workbench.

So some sort of a side pinch seems like it could be the direction to go.

One other possibility to consider is that the "tongue" could slide in and out of the main V-groove block for larger size gussets, using something like a slide rule mechanism.
 
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