Idea for T & G construction assist tool

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Victor Bravo

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All the talk about T&G got my brain cells all aflutter again.

When I built my Kolb tail surfaces I hacked and chopped out a simple and ugly tool that allowed me to match drill, and achieve better results than I should have gotten in the amount of time spent.

Now with all the printing of assembly aid tools and clever people who can actually do it, I want to re-introduce the idea to the people who can actually make a legitimate version pf this tool..

There ought's to be... a channel or grooved block of some sort that has an extension to one end of it, and the extension should have some sort of small drill bushing in it. Actually two or three drill bushings to establish rivet spacing.

So you have a piece of tubing laying down on your workbench. Sitting on top of this tube is a sheet metal gusset.You lay the tool down on the tube, with the "finger" or extension overlapping the gusset.

The tool puts the drill bushing over the gusset, and centered on the (not visible anymore) centerline of the tube. So when you drill through everything, the rivet hole goes through the gusset and the tube together, and the hole is centered on the contact patch of the tube, not offset. So your rivets are as good as they can be.

So if you are NOT building a CAD/CAM T & G fuselage, you can still achieve a very clean level of riveting workmanship without any of the holes be ing pre-drilled.

I'm guessing that even with a partially CNC'ed fuselage kit, there are still some gussets that will have 90 degree bends in them (for inboard longeron/upright/cross-member joints), or gussets that overlap more than one part, where it is too much trouble and trial/error to have everything perfectly match-drilled ahead of time.

Anyone else think this idea is good/bad/brilliant/ridiculous?
 

Aerowerx

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Pictures are worth 1000 words.;) Even a pencil sketch.

There are things for drilling holes in tubes, that consist of a metal bar with a v-grove length-wise down one side. And a series of holes of various sizes for various size drill bits. Do you mean something like that?
 

TFF

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It would be very easy to have a guide printed to match a design. Cluster of tubes with specific angles and such. A generic? maybe sort of. You don’t know number of fasteners needed so nothing pre drilled but maybe a holding hole for a cleco , angles are not generic.

Now in reality, how much time is this going to save you when you could lay out sides on some ply and draw a couple of intersecting center lines on a gusset to drill some holes. The plane, no matter how much prefab goes on, still has to be put together, and it will take you time. Number of started planes don’t count, only finished ones. Perceived easy planes still need nose to grindstone. You have to care more about finishing than easy.
 

Victor Bravo

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If somebody wanted to get clever, there could be some sort of clamp, toggle, rubber padded pinch mechanism, etc. built into this. So you slide it into place, toggle the clamp so it is fixed on the tube, and then you can drill through the gusset and the tube without risk of the tool sliding around or rocking on the tube.

As I said, this is not a perfect substitute for a whiz-bang CNC matched hole kit, but it would allow faster and less stresful construciton of scratchbuilt non-CAD tube and gusset fuselages, tails, etc.

There would likely have to be a couple of different tool sizes for various tube diameters, or some sort of parallelogram closure. Wait, that's it... two parallel arms that clamp together on the sides of the tube, making it a universal drill jig. More complicated to build the tool, but gives the tool more usable function.

The drill bushing holes would need to be #40, you'd use the small silver Clecos, then you can always go back and poke them out later for the larger Clecos.

Boy you guys are in trouble now, I'm in a brainstorming mood and I had to stay home from work because of these SoCal fires being blown toward me. I'll be lurking on this forum a significant part of the day :)
 
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Vigilant1

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Next--a three-chuck Robo-Drill that makes takes the place of the tang. One push on a lever and the three holes are done.
 

Aviacs

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What does T & G refer to as far as airplane construction?
As a woodwhacker, i can think of "tongue & groove" but not sure if that relates?

smt
 

Hot Wings

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The drill bushing holes would need to be #40, you'd use the small silver Clecos, then you can always go back and poke them out later for the larger Clecos.
Why limit yourself to just one size? Use an interchangeable bushing along with a couple of standardized holes in a hardened metal 'shoe'. Here is my interpretation of what you are proposing. Slide the "V" section along the tube and use the shoe to align the drill hole perpendicular to the gusset surface - and drill away. The notches on the ends can serve as witness to make sure you are on the intended line. With the hole a known distance from the end of the shoe you can also accurately locate the hole without actually seeing the center mark - kind of like an edge finder.jig.JPG
 

Aviacs

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DSC_0014.JPG DSC_0016.JPG DSC_0017.JPG In the interest of sufficient complexity.... :)

I think i would miniturize this; possibly put it on a sliding V-block base.

I agree with the idea of reaming & using press-fit liner bushings. Then insert working bushings for the size needed.
My tool above somewhat anticipates this, 7/8" being the max diameter, and other sizes can be used in it. Regular round bits run directly in the working bushing, paddle bits need to be fitted in a round holder.
 

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Hot Wings

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>>>insert standard Fritz rant<<<

...keeping in mind what this tool is for

What about a 3D printed shoe with steel inserts for drill guides?
I was specifically thinking about you printing up one of this exact configuration. We expect to see the finished tool tomorrow afternoon! :p
 

FritzW

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We expect to see the finished tool tomorrow afternoon! :p
If you want it by tomorrow afternoon you need to send me the STL files (or the SLDPT's) tonight before Star Trek comes on ;) It can be white, orange, black or yellow.

EDIT: should the mounting lugs and the big block be a single unit?
 
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litespeed

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Thread drift..............

Is there a new Star Trek?

You must tell us to maintain international peace.

Live long and prosper
 

FritzW

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There's Star Trek Discovery but it's such a dismal failure that we're not allowed to mention it on international forums. I just binge watch the old stuff and throw in a little Firefly to mix it up.
 
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