Idea for T & G construction assist tool

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Victor Bravo

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I will surely be relinquishing the Rube Goldberg Complexity Award for writing this, but really I do not see a need for a hinged or articulated "shoe" on a tool for THIS kind of use.

Basically the tool is only to guarantee you drill through the apex (tangent line) of the tube under the gusset. It's all on the same axis, because you are drilling the same tube you are using as a guide. Unless you have a curved tube, it's all in one straight line.

A v-block with a tongue like my sketch would do that acceptably, while being the easiest to fabricate, machine, print, etc. To me, the most important thing by far is that with the simpler version of the tool, the same amount of tool manufacturing/machining/printing can yield three or four tools (of different hole sizes or rivet spacings) in the same time as one complicated articulating tool.
 

Hot Wings

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If you want it by tomorrow afternoon you need to send me the STL files (or the SLDPT's)
You expect us to do 'some' of the work?!

If you are serious about trying to do something like this I could work up a real model, but I can't say just when. The weather is "nice" today and I have outside work that needs to get done.

I will surely be relinquishing the Rube Goldberg Complexity Award for writing this, but really I do not see a need for a hinged or articulated "shoe" on a tool for THIS kind of use.
Without the shoe the simple tool would have to be made adjustable for each combination of tube diameter and gusset thickness or there is the possibility of slanted drilling. The articulated shoe solves this, but does introduce the need for a third hand, or some kind of quick clamp..........Thinking about version B.
Jig B.JPG
Thinking about version B.

Version B.JPG
 

Victor Bravo

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Oh my heavens... :)

Technically, yes you would need to have the drill bushing able to move up and down in the Z axis a little to compensate for gusset thickness. However, recall that the "hole finder" or "strap duplicator" tool we all use every day on overlapping skins relies on a small amount of spring flexure, both to "install" in position on the skins... and to "lower" the drill bushing down onto the upper skin.

I believe this is clearly one of those instances where the Z axis movement does not have to be quite that precise. If we were making a drill jig for something using 1/4" plate, where the main wing pins are going through it, then yes of course. But in this case for a T&G Pietenpol or Baby Ace type of affair, we are going to be talking about .025, .032, and .040 gussets sitting on top of 3/4, 7/8, and one inch tubes.

The basic idea (at least in my cracked skull) was that you would have a few different versions of this, the same as most of us have a few strap duplicators laying around. One universal tool with change-able bushings is a wonderful daydream, but most of us would rather just pick up the right size drill jig from the workbench and put it on the tube five seconds later - not unscrewing one drill bushing and then looking for where the other bushing rolled under the bench, etc.

The good part of this is that the tool should be simple and cheap enough that buying or making five different sizes is not a significant investment.

Now manufacturing or fabricating these tools... IMHO the main handles should all be identical (printed, machined, or shop-fabbed), and simply have different size bushings glued or threaded into the ends.
 

Hot Wings

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Oh my heavens... :)
However, recall that the "hole finder" or "strap duplicator" tool we all use every day
A flexible tongue - good thought! Still 3D printable using a hack saw blade as the connector.

Just another example of how good software makes it easier and faster to make mistakes............:oops:
 

FritzW

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I don't think the difference in gusset thickness is enough to worry about (.016 at the thinnest and very few gussets at .040 or bigger). What is probably a bigger issue is the height difference due to the tube diameter.

Of course it would change a little with the shape of the V groove but it's still a much bigger deal than gusset thickness. Hot Wing's adjustable block is simple enough and would solve the problem. ...let's print one and see.
Drill guide LO.jpg
 

FritzW

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That worked. ...Unless I'd get run outta town for doing it, I might tweak it a little and make it a little more "maneuverable".
 

Hot Wings

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That worked. ...Unless I'd get run outta town for doing it, I might tweak it a little and make it a little more "maneuverable".
Do with it as you like! It was offered only as a base to work from as you see fit. I have no idea what kind of clearance you need with your printer or what you might have in the scrap drawer for the other little bits.

Drill bushings:
https://woodworker.com/18x38x12-drill-bushing-mssu-821-862.asp

McMasters Carr probably has a better selection?
 

FritzW

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The "one tool per tube size" is great but the set will cost 37 cents more than an adjustable one. :rolleyes:
 

FritzW

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Here's the pocket version of Hot Wings drill guide, seems to work great on any size tube.

It took a little "file to fit" because I didn't leave clearance on the slide...
20191114_185317_resized_1.jpg

20191114_185512_resized.jpg

Until you got a couple of clecos in the gussets it would take three hands (mentioned earlier). After playing with it for a little while, I'm not sure it wouldn't be easier just to put a straight edge on it instead of a drill guide, mark your drill line and kick it old school.
TnG Ruler.jpg
 

radfordc

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After looking at the one I made, I would make changes....
- reduce overall length from 9.5" to 6"
- only have one drill bushing located 1" from end of tool, or at whatever rivet spacing you want
- include a half round hole on the end of the tool to match the diameter of a cleco fastener; after drilling the first hole install cleco and butt tool up to it to drill next hole.
 

Victor Bravo

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Like like like like!!!!!

Radford, that is exactly what I had in mind. Seeing three or four different guys bring an idea like that to life in actual parts is truly inspirational !

Try the "first hole" tool on one end, and the cleco-abutting design on the other end of the same stick :)
 
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Victor Bravo

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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. Would be a small way to give something back to HBA. Would also open up a lot of additional T&G design ideas.
 

Aerowerx

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.... But in this case for a T&G Pietenpol or Baby Ace type of affair, we are going to be talking about .025, .032, and .040 gussets sitting on top of 3/4, 7/8, and one inch tubes.....
Why not just pick a single gusset thickness and live with the minuscule weight penalty?
 
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