Guillotine Fin Jig Plans

Ok, Apogee sells the Guillotine Fin Jig, and it looks super sweet. If you are cheap like me and in possession of sufficient power tools you look at the pics on Apogee's website and think I could do that...maybe. Anyhow, I enquired with Ted Macklin, the inventor about obtaining plans. He does sell them for $12. They are excellent quality, and contain a parts list, detailed assembly instructions, and full page blueprint style drawings of each component. If you can follow plans, AND HAVE THE ABILITY TO PRODUCE PARTS AT 1/16" TOLERENCES, they are all you need to make a fin jig of your own.

I made the entire thing from my scrap pile (why most of the wood is overkill thickness and scruffy looking), and ended up only needing to buy about $25 worth of hardware (thumb nuts) and aluminum angle to complete the job.





Now a bit of fine print stemming from the fact that at least one thread on this subject has been locked for what appears to be related the points below. That sucks, and Ted has a good product that should have a living thread for posts.

- I meant what I said about 1/16" tolerances. Any mistakes project out through the aluminum rails and only magnify with distance. There is one cut I think has some leeway, and that is the stationary end "V-cut". You can overshoot that one a touch, as I did with my router, as long as it is centered. There is ZERO forgiveness in the top of the operable end diamond cut and the centering cleats. You screw up there and you are remaking the ends, period. I know, because that is my third set of ends...learning a new router.

- The fin jig on Apogee's website is pricy, but totally worth it. Having built one, and now appreciating what time goes into it (probably 4-6 hours if I didn't have to redo the operable ends three times), I don't see how there is sufficient profit for Ted and Tim in those, but more power to them. Please do not hijack this thread to complain about Apogee or their pricing, it's not about that.

- You could probably reverse engineer this jig from the pics floating around, but why. To save $12, and thereby rip off the rocketeer inventor in the process? That would be decidedly uncool, and not behavior fitting of the brotherhood of smoke.

- Having set this up one time to take the pics above, I can see it will be a standard part of building now.


Disclosure: Ted is a fellow DARS member, a friend, and sometimes a pain in the **s (but aren't we all). However, I am not being compensated or cajoled into making this post. I am posting because it is a really good product, and if like me, you are just too cheap to spring for one from Apogee, you can get the plans for $12 and build your own. I'll drop Ted a PM, so he can cruise by and post his contact info that way it is all in one thread.

Thanks Chris. Me? A pain in the **s? Who knew? :surprised:

Seriously, I appreciate your thoughtful review and comments about my tool. I'm sure you will be using it on a regular basis and so will your boys. As for contacting me about a set of plans, I don't as yet have a dedicated website but will in the near future. In the meantime, anyone who wants to purchase a set of Guillotine Fin Jig plans may do so by first sending a PM to tmacklin here or on YORF so we can exchange emails. I also make custom sizes at custom prices if you want something special.

BTW, nice very job on the jig! It goes a bit faster after you make a couple hundred of them! It's actually easier to make them out of thicker material when making them as a glued and nailed box. The commercial units I make for Apogee use thinner material primarily because of the weight and associated shipping costs.

I, on the other hand, have been totally bribed, cajoled, begged and visited by thugs in the middle of the night. But not about Ted's jig. THAT was an inspiration and stroke of genius! Ted has been a buddy for quite awhile and I'm sure if I lived in Texas we'd both have either a) warrants out for us or b) records with the local law enforcement. I literally won't build anything (I scratch build 90% of the time) without the jig. Even with preslotted airframes. Spin is only induced by my airfoiling-nothing else. I'd love to see a 'mini-jig' for the 'other' guys-they'd never go back to using anything else.

[video=youtube_share;AbZYZHYtdok]https://youtu.be/AbZYZHYtdok[/video]

You can't blame Texans for their prickly nature. The Devil made Texas. Listen to the lyrics.

I agree with everything the OP said. I also built this jig after buying a set of plans from Ted and I seriously doubt that it saved me any money. The tolerances are very small and if anything 1/16" is too much error. Ted is a heck of a craftsman to be able to turn these things out in quantity, although I understand that he recently switched to using upscaleCNC to produce the critical pieces.

The jig itself is incredibly useful and it really takes the frustration out of mounting fins. Most importantly, my kids (4 & 6 yrs old at the time I built the jig) get mad at me if I try to help them build their rockets. They have Ted's jig and can do it themselves.

Ted was very helpful to me during the process of making it and the $12 price for the plans is embarrassingly low for plans of such high quality. If you build a Macklin fib jig, but the plans first, they are well worth it.

This is a serious question.

If the tolerance of 1/16" is a optimistic estimate, wouldn't it would be better to make the chassis/box longer to spread the error out over a longer distance? An error of 1/16" in a 24" box is half the angular distance of the same error in a 12" long box.

I understand that for commercially produced units the shipping weight, container, and material costs must be considered but for someone building from Uncle Ted's...wait, wrong Texas Ted...TMack's plans it seems like greater accuracy could be achieved with a longer box.

o1d_dude said:

This is a serious question.

If the tolerance of 1/16" is a optimistic estimate, wouldn't it would be better to make the chassis/box longer to spread the error out over a longer distance? An error of 1/16" in a 24" box is half the angular distance of the same error in a 12" long box.

I understand that for commercially produced units the shipping weight, container, and material costs must be considered but for someone building from Uncle Ted's...wait, wrong Texas Ted...TMack's plans it seems like greater accuracy could be achieved with a longer box.

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That's not really where the tolerances come into play. It's more a matter of what is happening in-plane, because the two squares of the guillotine have to line up very closely in the vertical direction in order to properly center the fin on the tube at that end. It is difficult to explain, but becomes obvious when you try to build the thing and get it wrong the first time.

Making them longer would reduce any associated fin cant, but that isn't really the issue that I think the OP was talking about. You can't really make one of these without first constructing a very good router jig and thinking the process through very carefully - i.e. cut the hole in this piece, then that piece, but flip that one over so that they line up, clamp it along this edge but not that one, etc.

Any moving part must have some tolerance or it will be impossible to move because of friction (think piston rings). The trick is to fabricate the component parts as close to the theoretical as possible yet leave enough slack so that there is minimal error with regard to the vertical centerline. Everything must relate to this centerline in both the vertical and horizontal axes. When I first started making these for Apogee, I had a discussion with Tim Van Milligan about how long the device should be. Tim initially wanted it to be shorter in order to work with smaller kits but I made the argument that if it became short enough to work with the shorter body tubes it would be at the sacrifice of longer ones. I won that argument by comparing the accuracy between a rifle and a pistol. So. what evolved was this:

Starting with the standard then available Estes body tubes (BT5 through BT80) the maximum square opening had a diagonal dimension of 3.75" resulting in a square of 2.651 inches on a side. With 1 inch on each side for the slots, the width became 5.75" and I made the height the same. This also allowed me to rip all parts to the 5.75" dimension and crosscut all parts at that table saw setting except for the side panels. (The 5.75" dimension had the added benefit that I was able to obtain four rippings from the nominal 24" plywood from Woodcraft, thus minimizing waste.). The length was governed by the length of standard Estes body tubes, which is 18.00". Allowing for a decent overhang on the business end evolved into an overall length of 9.00", minus a blade thickness, again to save waste. An individual builder could make the thing any convenient length he/she wanted. (The new improved small unit will accept tubes as large as 3.09")

Probably the best way to improve accuracy of the device would be to make the end panels taller, which would minimize the potential angular error on the vertical (radial) axis. This would also increase the height of the side panels and add material costs all around. In any case, the V-slot formed by the two beveled cleats must fall as close as possible to the theoretical centerline or all bets are off.

When I began this odyssey I didn't even have a table saw and was ripping my material with a circular saw run against a straightedge. There was a lot of edge sanding involved and the finished product was nowhere near as good as it is today. But these early units are now collectors items, so don't throw them away!

The accuracy of the finished product is entirely dependent upon one's eyesight.

fyrwrxz said:

I, on the other hand, have been totally bribed, cajoled, begged and visited by thugs in the middle of the night. But not about Ted's jig. THAT was an inspiration and stroke of genius! Ted has been a buddy for quite awhile and I'm sure if I lived in Texas we'd both have either a) warrants out for us or b) records with the local law enforcement. I literally won't build anything (I scratch build 90% of the time) without the jig. Even with preslotted airframes. Spin is only induced by my airfoiling-nothing else. I'd love to see a 'mini-jig' for the 'other' guys-they'd never go back to using anything else.

Click to expand...

Making a Micro-Maxx sized version of this would be quite a challenge and beyond my current skill set. The smaller something gets the more difficult it would be to achieve the level of accuracy being demanded by those who are into miniature creations. I would think that it would need to be fashioned of metal using some pretty sophisticated CNC technology. Now up-scaling the Guillotine is entirely feasible and would actually be easier because you wouldn't need to make router pattern jigs. You could just screw straightedges directly to plywood end panels and use them as permanent router guides.

When I get caught up a bit I may just tackle a monster Guillotine Fin Jig, something that will accommodate 36" diameter sewer pipe for you high power dudes. Might need a block and tackle on each end to to raise and lower the sliding end panels, or maybe some kind of medieval rack and pinion? :surprised:

Ted, I wonder if I could 3d print one for micromaxx stuff...if you can sketch something out with dimensions I could give it a try. Although I suspect quality would be much improved when I get the new printer finished.

Would be pretty easy to produce I would think.

wfcook said:

Ted, I wonder if I could 3d print one for micromaxx stuff...if you can sketch something out with dimensions I could give it a try. Although I suspect quality would be much improved when I get the new printer finished.

Would be pretty easy to produce I would think.

Click to expand...

I'll send you something soon via email.

Cool

Apogee website says it will fit thin wall 3" tube. Will it fit Loc 3" paper tubing?

accpool said:

Apogee website says it will fit thin wall 3" tube. Will it fit Loc 3" paper tubing?

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The square opening of the small Guillotine is 3.093 inches and it is 6.187 inches on the large Guillotine. Apogee shows the LOC to be 3.10 inches so I think the answer is "no".

Wow, a fin-jig for Micro-Maxx stuff...that would be so cool.

I built two of them, and their like the old potato chip ads...you keep reaching in the bag and pull out more!

tmacklin said:

The square opening of the small Guillotine is 3.093 inches and it is 6.187 inches on the large Guillotine. Apogee shows the LOC to be 3.10 inches so I think the answer is "no".

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Ok, thanks for spec on jig.

In use.

Now that Tim has his laser cutter toy, could he produce micro jigs from scaled down Texas Ted plans?

Are the plans for the small ($90) version or the large ($195) version?

NikeMikey

NikeMikey said:

Are the plans for the small ($90) version or the large ($195) version?

NikeMikey

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The plans are generic and show an example that if built exactly would produce a jig with a square hole that has a 4 inch diagonal and will accept a maximum tube diameter of 2.828 inches. It is easy to upscale or even downscale to whatever size the builder desires because any size functions the same. There are three pages of text and five pages of hand drafted line drawings that show how to form the various parts. The commercial units sold by Apogee are not the same size as shown in the example design package but could easily be made so. If you are interested in a set of plans, the price is still $12 and you can still PM me here.

Thanks for your interest.

Ted Macklin

rocketguy101 said:

Now that Tim has his laser cutter toy, could he produce micro jigs from scaled down Texas Ted plans?

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Sure. Anyone with the proper tools could make one of these including a micro sized version. Proper tools is the key, especially when making something very small because "small" reduces the margin of error and thus requires a greater degree of accuracy in the component parts. I could be wrong but I don't see a great demand out there for a micro version. I have thought about making one but my plate is pretty full just keeping up with the original and large ones sold by Apogee. A really big version would be a piece of cake except for the material costs. Bigger is easier.

tmacklin said:

When I began this odyssey I didn't even have a table saw and was ripping my material with a circular saw run against a straightedge. There was a lot of edge sanding involved and the finished product was nowhere near as good as it is today. But these early units are now collectors items, so don't throw them away!

Click to expand...

I bought one when I first saw it on Apogee's website. It does exactly what it was designed to do, every time, and has been one of my best investments in rocketry! Mine has a yellow sticker with a handwritten #10 on it. As a collectible, does that signify anything?

SMR said:

I bought one when I first saw it on Apogee's website. It does exactly what it was designed to do, every time, and has been one of my best investments in rocketry! Mine has a yellow sticker with a handwritten #10 on it. As a collectible, does that signify anything?

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I'm glad you like it and hope that it gives you many more years of use. As for the "yellow sticker", I can only assume that Apogee placed that sticker upon it. I haven't done a recent count, but I'd guess I've made about 400 of them so far. I had some hiccups along the way which forced me to refine my manufacturing techniques which is a good thing.

I like the medium size one I picked up from you. Works great for mpr and some hpr.

AcidPaintball said:

I like the medium size one I picked up from you. Works great for mpr and some hpr.

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That's great. I only made three of these IIRC, selling two and keeping one for myself. I hope you will post some pics sometime!

Do you have any kind of adapter that allows u to purchase the big one, and still use small tubes if u build a low power?
I'm most mid and high, but now holding LPR 4-H work shops

Nick@JET said:

Do you have any kind of adapter that allows u to purchase the big one, and still use small tubes if u build a low power?
I'm most mid and high, but now holding LPR 4-H work shops

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Sorry I missed your post. No, I do not make such an adapter but one could easily be made by the consumer by fabricating two boards of equal thickness into an angle and laying it into the trough to reduce the effective aperture. You would probably need to cut out the radius corners of the fixed end panels in order for the adapter to lay flat. The angles for the large unit are made from 2" x 2" x 1/8" aluminum angle and would be difficult to use for smaller rockets. I still sell design plans which could easily be modified for different size ranges. Please PM me if you are interested.

I just ordered the mid-sized jig from Macklin Missile Works (that's probably the best website name ever). Now I can stop stressing out over attaching fins
(and this is my first post here)

Welcome.

Pictures of rockets and launches are encouraged.