Fin Alignment Jig

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Elon

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I based this on the "guillotine" jig shown at Apogee, but made it capable of handling tubes as large as 3" and tubes too small for a rocket. The tube shown in the pictures is a 2.56 LOC Precision tube and a fin from a scratch-built 50s style sci-fi design. IT took a little less than a work-day to build and seems to work great.

Now that the jig is done I have to actually build the rocket!

Fin Alignment Jig 02 LR.jpg

Fin Alignment Jig 03 LR.jpg
 
I based this on the "guillotine" jig shown at Apogee, but made it capable of handling tubes as large as 3" and tubes too small for a rocket. The tube shown in the pictures is a 2.56 LOC Precision tube and a fin from a scratch-built 50s style sci-fi design. IT took a little less than a work-day to build and seems to work great.

Now that the jig is done I have to actually build the rocket!
You, sir, are a tool builder. I applaud that.

Now get busy on that rocket! :D
 
Elon is a class act and has PM'd me about my concerns. I'd fly with him anytime.

Here https://www.rocketryplanet.com/forums/showthread.php?t=9089 is the original disclosure of my design. If anyone is interested in building their own Guillotine Fin Alignment Jig with their own hands and using their own tools, feel free to PM tmacklin here, on Rocketry Planet or on YORF.

I'll sell you an autographed design drawing for a fair price. :y:
 
Elon is a class act and has PM'd me about my concerns. I'd fly with him anytime.

Here https://www.rocketryplanet.com/forums/showthread.php?t=9089 is the original disclosure of my design. If anyone is interested in building their own Guillotine Fin Alignment Jig with their own hands and using their own tools, feel free to PM tmacklin here, on Rocketry Planet or on YORF.

I'll sell you an autographed design drawing for a fair price. :y:

Well I am not as handy as you all .. nor do I have the materials. How much for an autographed jig shipped to Sacramento CA? :D
 
Well I am not as handy as you all .. nor do I have the materials. How much for an autographed jig shipped to Sacramento CA? :D

You want the actual jig, not just the design drawings, right?

The current retail price of the standard size Guillotine Fin Jig is $85 U.S. I would charge my actual cost for postage to your ZIP. (My signature is priceless so I'll put it on for free.)

As for the plans, by the original author no less, how's about a check or money order for $10, postage paid?
 
What's the largest tube it accepts?

The standard Guillotine Fin Jig, the one I make for Apogee, will accept all standard Estes body tubes, BT5 through BT80, and anything inbetween. It will accomodate fin thicknesses from 0.00" to about 0.41" (7/16").

I also have tooling and routing jigs for a larger version which will accomodate body tubes up to about 6 3/16", if memory serves.

INTERRUPTION

The larger unit is made with thicker and thus heavier materials. I have thus far only made one of these and it was shipped to a customer in California as a kit. The overall size when assembled was about 12 x 12 x 30" long and the customer purchased the 3" x 3" x 1/4" aluminum fin alignment extrusions locally to minimize shipping cost. I believe I charged this customer a $35 set up fee, $40 for materials and $125 labor to fabricate and the parts. The postage was $27.

BTW, I use Baltic Birch plywood in nominal 1/4" (6MM) and 1/2"(12MM) thicknesses because it is dimensionally stable. The 1/4" plywood has 5 plys and the 1/2" stuff is 7 ply. This is not the crap you find at the Big Box stores. I charge extra to make crap.
 
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Very fine looking! Pocket screws, countersunk machine screws, fancy knobs... Lucky. I may just throw one together that will go up to 5" tubes. I've considered something using a small rotary table for accuracy in fin angles. Some day!
 
I based this on the "guillotine" jig shown at Apogee, but made it capable of handling tubes as large as 3" and tubes too small for a rocket. The tube shown in the pictures is a 2.56 LOC Precision tube and a fin from a scratch-built 50s style sci-fi design. IT took a little less than a work-day to build and seems to work great.

Now that the jig is done I have to actually build the rocket!


You are obviously a skilled woodworker. Even so, it took you a "...little less than a work-day to build...". I'm sure you would become more productive if you were to make more. (I certainly did, but it took a lot of mis-steps, the purchase of more power tools and the creation of numerous manufacturing jigs.)

My point is this: if anyone thinks I'm getting rich making these, they should ask themselves just how much they'd have to charge a consumer for just one, completed model rocket.

Don't give up your day jobs! :wink:

P.S.
Elon, I want to see a review/build thread on the Guillotine once you get a chance to build a rocket with it. :)
 
tmacklin- You sir, are indeed a pioneer in this arena. No matter how many knockoffs there are you were the first with a very innovative and functional design. As a former tooling engineer, I recognize your achievement as a boon to our sport and an essential contribution to our hobby as a whole. As poor as it may seem, all I can offer is my sincere thanks to you for your efforts and invention. :handshake:
 
... and there is a very good chance I'll be wanting some plans, autographed of course. :wink:
 
Tom, thanks much.

I have lots of tools, so no excuses there. I suspect I could make another one now in about an hour or so given the resources in my shop, faster if I was making ten or so at a time, or if I was racing against a stringent deadline. Of course you did all the hard work upfront, though despite even that I managed to misunderstand how you designed it to work and wasted half-a-day building something non-functional only to throw it away and start again. Among other things, I make all aluminum pedal boards for electric guitarists, and I sometimes wonder why given the time it takes to make them and how low the margins are on a per unit basis. Pride I suppose, since their pretty and seem to work well. There is no doubt that folks little appreciate how many tens of hours and how much money goes into getting a product like your jig right, never mind what it takes to build one, or a hundred.

Check out build thread #1: at https://www.rocketryforum.com/showthread.php?t=32807. Your jig works brilliantly. Here's a challenge though: I'm starting another build on a 2.56 rocket that, because of its design, can't pass into the jig body. I figure I'll put a tube and coupler in the jig and hang the rocket on that, so artificially lengthening the rocket while the fins are applied.

Also, someone in one of the threads asked me if I had to mark pencil lines on the body tube to use the jig, which got me to thinking about how to possibly indicate relative degrees on the jig itself. Of course whistles and bells often cost money, and the struggle is to make something complete enough to be maximally useful while still remaining within that bandwidth we call "affordable." I didn't say so to the fellow at the time, but its just not that much bother marking lines on a tube, and I like the visual reference while I'm building to ensure everything is copacetic.

Really though, congrats on the jig. It's a top notch idea - brilliantly stable, super easy to use, totally variable, durable. I recommend anyone who plans to build more than one rocket shoot Ted a note and order up a jig. The first rocket build with it will make it all worthwhile. And while I'm sure the [autographed] plans are nice, I suspect it's actually cheaper when all is said and done just to have Ted build one for you so you can get back to building rockets. Though I seem to spend an inordinate amount of my own time building jigs and organizational stuff, I generally prefer to work in my shop rather than on it.

- E


You are obviously a skilled woodworker. Even so, it took you a "...little less than a work-day to build...". I'm sure you would become more productive if you were to make more. (I certainly did, but it took a lot of mis-steps, the purchase of more power tools and the creation of numerous manufacturing jigs.)

My point is this: if anyone thinks I'm getting rich making these, they should ask themselves just how much they'd have to charge a consumer for just one, completed model rocket.

Don't give up your day jobs! :wink:

P.S.
Elon, I want to see a review/build thread on the Guillotine once you get a chance to build a rocket with it. :)
 
Tom? No. Ted? Yes! :)

Thanks for your "thumbs up" on the device.

My original, prototype device as was featured on Rocketry Planet last summer and on a YouTube video by Doug Sams was made from scraps I had on hand around my shop. I cut and slotted the parts with an old Sears Craftsman jig saw and cut the aluminum parts by hand with an old hacksaw and finished with a hand file. It was far from "perfect".

After working a deal with Apogee Components, I made certain improvements, foremost of which is the elimination of all aluminum parts except the fin alignment rails and the addition of side panels which serve the dual function of forming a guide for the operable end panels and giving rigidity to the entire assembly. This was done to reduce the number of drilling and screwing operations as well as the cost of this hardware. I also made the v-groove mechanism out of basswood and the square hole in the end panel is made with a router in a custom made jig.

Here's a pic of the standard production version as now sold by Apogee. (I just sent them six more)

Guillotine Fin Jig.jpg

And here, is a predecessor to the Guillotine, which worked quite well but was not adjustable. Plus my office/shop was getting cluttered with jigs in various sizes. This clutter is what germinated the Guillotine.

View attachment Fin Jig.pdf

The Guillotine could be made in virtually size including overall length. I have in mind a modification which would allow the user to adjust the length, much like a slide trombone. The Stretch Guillotine? Sounds gruesome, don't you think?

BTW, the standard version will accomodate tubes up to 2.65", so your 2.56" tube would have just slid in. Using a coupler with an additional length of tubing is precisely what I do for boosters or short rockets.

An indexing mechanism poses a problem for the Guillotine because the aperature, being adjustable, changes the geometry for each tube diameter. One easy way to mark fin locations is the use of a pair of plastic funnels mounted to a pair of "bookends". You will notice that these funnels have ventillation ribs which are usually located at either 90 (four fin) or 120 (three fin) degree increments. Credit my son, Charlie Macklin, EIT, for coming up with this idea.

I wish I could make these quicker and thus more affordable so that more people could enjoy the benefits of its features. :)




Tom, thanks much.

I have lots of tools, so no excuses there. I suspect I could make another one now in about an hour or so given the resources in my shop, faster if I was making ten or so at a time, or if I was racing against a stringent deadline. Of course you did all the hard work upfront, though despite even that I managed to misunderstand how you designed it to work and wasted half-a-day building something non-functional only to throw it away and start again. Among other things, I make all aluminum pedal boards for electric guitarists, and I sometimes wonder why given the time it takes to make them and how low the margins are on a per unit basis. Pride I suppose, since their pretty and seem to work well. There is no doubt that folks little appreciate how many tens of hours and how much money goes into getting a product like your jig right, never mind what it takes to build one, or a hundred.

Check out build thread #1: at https://www.rocketryforum.com/showthread.php?t=32807. Your jig works brilliantly. Here's a challenge though: I'm starting another build on a 2.56 rocket that, because of its design, can't pass into the jig body. I figure I'll put a tube and coupler in the jig and hang the rocket on that, so artificially lengthening the rocket while the fins are applied.

Also, someone in one of the threads asked me if I had to mark pencil lines on the body tube to use the jig, which got me to thinking about how to possibly indicate relative degrees on the jig itself. Of course whistles and bells often cost money, and the struggle is to make something complete enough to be maximally useful while still remaining within that bandwidth we call "affordable." I didn't say so to the fellow at the time, but its just not that much bother marking lines on a tube, and I like the visual reference while I'm building to ensure everything is copacetic.

Really though, congrats on the jig. It's a top notch idea - brilliantly stable, super easy to use, totally variable, durable. I recommend anyone who plans to build more than one rocket shoot Ted a note and order up a jig. The first rocket build with it will make it all worthwhile. And while I'm sure the [autographed] plans are nice, I suspect it's actually cheaper when all is said and done just to have Ted build one for you so you can get back to building rockets. Though I seem to spend an inordinate amount of my own time building jigs and organizational stuff, I generally prefer to work in my shop rather than on it.

- E
 
Ted, are you really selling plans for your jig? I would be interested in purchasing them so I could build my own. Sure I'm pretty handy and have built various jigs but yours is a work of art! Mostly I have tons of scrap lumber and parts. PM me if you would.
Ken
 
Oops. Ted.

I make Estes-style marking guides in AutoCAD, print them to scale, and use a piece of aluminum angle as a straight edge since it self centers along the length of the BT - works well so far. I could make a bunch of .pdf's of different size marking guides if people wanted them.

- E

Tom? No. Ted? Yes! :)
 
Oops. Ted.

I make Estes-style marking guides in AutoCAD, print them to scale, and use a piece of aluminum angle as a straight edge since it self centers along the length of the BT - works well so far. I could make a bunch of .pdf's of different size marking guides if people wanted them.

- E

I use the aluminum angle marking method as well only I usually just make a paper wrap and then use a scale or ruler placed diagonally across parallels of that length and then subdivide for the fin increments, usually three or four. If I were smart, I'd put these into a manilla folder after I wreck the bird so I wouldn't have to do it again.

Then I'd probably forget where I put the folder, just like I do with passwords. :roll:
 
The designer of the guillotine jig from apogee is a regular member of TRF and has posted in this thread already. For $12 he will sell you a copy of the plans, as it is a commercial venture for him.
 
...

Please have a look at the attached files. Let me know what do you think.


...

Since you asked...

Cloning has a long tradition in our hobby. Cloning a current commercially available product is considered 'bad form' by some. (But I'm not naive enough to think that it isn't done, maybe alot)

https://www.apogeerockets.com/Building_Supplies/Tools/Guillotine_Fin_Jig

I think Ted will still sell a copy of his plans for DIYers, as outlined in this thread from earlier this year: https://www.rocketryforum.com/showthread.php?123088-Guillotine-Fin-Jig-Plans

So clone away, but maybe don't post about it on rocketry forums.

That's what I think :2:
 
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