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tmacklin

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...about making a miniature version of my Guillotine Fin Jig. If there is enough interest to justify the cost of down scaling for production of this device it could be done. Any input would be appreciated and I cannot proceed without it. Thanks.
 

tmacklin

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I've got a slogan I could use but...well...you'll just have to use your imaginations. :y:
 

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I might be interested.
 

Kruegon

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I'm heading into MMX. Depending on price point I might be interested. What's the tube range going to be?
 

tmacklin

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I'm heading into MMX. Depending on price point I might be interested. What's the tube range going to be?
I have no idea what the tube range might be and to some degree I am dependent upon those of you who are experienced in this arena. It will require some thought and may need to be made from materials other than wood or wood products.
 

EXPjawa

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I think your current small jig works quite well from BT55 or 60 size and up. I've used it on smaller, but if the fins are small, it can be borderline useful. If the proposed compact jig handled tubes from .5" to 1.5" diameter, that would be ideal IMHO. Keeping in mind, of course, that models that size also have fins that are equally small in span... If the price was more or less in proportion with the other jigs, I'd likely buy one.
 

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Is it so much a diameter issue or body tube length issue? I've seen the smaller version used down to BT-20 without any problems. A smaller diameter tube may need something to extend the angles to touch the fins but the larger problem would be the ability to hold the tube at both ends of the device. Even the Estes Mega Der Red Max needed to mounted to a mandrel to span from one support to the other.
 

TopRamen

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Do you still sell the plans?
There's probably like 20 people in the entire world that take MMX seriously enough to want one, and if they are such fine micro craftsmen, they should certainly be able to build a MMX size Jig. I made a down scale using the plans I got from you, but like lots of other things, now that it is complete I just need to get around to assembling it. I have nearly 30 projects or more right now that are complete and dry fitted, but require final assembly.
Your Jig was a challenging build for sure, as I only use hand tools, to include a hand cranked drill.
The digital caliper is a must for a Jig build, but if you want to make small rockets with a precision jig, yours is the best design I can think of.
I really could not find the time to even try to make any improvements to it.
If they are economically priced as kits, I'de actually like to get one because I enjoyed scratch building your plans so much.
A wooden one would be kinda neat, but at such a tiny scale, you should offer one that is machined from carbon fiber plates.

Dry Fit Macklin Jig 2016-06-21 003.jpgCarbon Fiber Micro Mosquito 2016-06-30 007.JPG
 
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fyrwrxz

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Always wanted a guillotine in my pocket, but that's just me......
( I just KNOW I've set myself up, but what the hay...)
 

Micromeister

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I have no idea what the tube range might be and to some degree I am dependent upon those of you who are experienced in this arena. It will require some thought and may need to be made from materials other than wood or wood products.
Like CW & Krurgon, I'd be interested depending on the price point.
For us MicroMaxxer's we would need a jig that would handle Tubes from T2 (.246" OD) to prehaps as large BT-50 (.976" OD). To be perfectly Honest BT-5, BT-20 and BT-50 size models are ONLY 3,4 & 5 motor clusters. Most micro powered models BT-5 and Up are not very good flying machines.
The rest of our range would be T2 (.246") T2+ (.281") MMX minimum motor size, T3 (.375"), T4 (.448"), with BT-5 (.544"), BT-20 (.736") and BT-50 Only of minor importance.

More important I my mind; Many of our Micro Rockets are no more the 4.0" long. Some with fins smaller are less then 1/2" Root to tip so some very small Alignment angles would be required. Many of our models use fin materials as thin as .005" and .010" Waferglass (super thin G10). Styrene and Lexan fins down to .010" and as thick as .030", Standard 1/64 and 3/64 3ply aircraft Plywood, and Balsa and Basswood 1/20th" .032" and 1/16" is just about the max.

I've looked before for Tiny Brass, Stainless Steel or Aluminum 3/8" or under Angles rigid enough for such use without much luck.

I've looked at fabricating a Micro Guillotin type fin jig a couple times in the past just for fun. My inclination would be to fab. the either thing from all aluminum, Stainless steel or possibly a high strength laminate. Woods; even Aircraft birch Plywood would seem to be to thick for such a project. The alternates materials however I fear would make this little machine far to expansive to purchase????

I'll keep my eye on this thread, If you need any specific specs on materials or processes used please let me know.
 

tmacklin

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Do you still sell the plans?
There's probably like 20 people in the entire world that take MMX seriously enough to want one, and if they are such fine micro craftsmen, they should certainly be able to build a MMX size Jig. I made a down scale using the plans I got from you, but like lots of other things, now that it is complete I just need to get around to assembling it. I have nearly 30 projects or more right now that are complete and dry fitted, but require final assembly.
Your Jig was a challenging build for sure, as I only use hand tools, to include a hand cranked drill.
The digital caliper is a must for a Jig build, but if you want to make small rockets with a precision jig, yours is the best design I can think of.
I really could not find the time to even try to make any improvements to it.
If they are economically priced as kits, I'de actually like to get one because I enjoyed scratch building your plans so much.
A wooden one would be kinda neat, but at such a tiny scale, you should offer one that is machined from carbon fiber plates.

View attachment 296567View attachment 296568
Yes, I still sell the plans and they still sell for $12 on my website. You certainly did a fine rendition of my contraption using carbon fiber, especially considering your use of hand tools only. Fantastic actually.

From what little research I have done on these tiny rockets, I understand that the motors are 6 mm OD x 26 mm long. Thus a minimum diameter rocket would require a BT 2.5 having an OD of 0.281 inches.
I'm thinking the range of the variable opening should fall between 3/16" minimum to 1 3/8" maximum, or BT2 to BT55. The length of the device is determined by the finished design of the rocket and must allow not only for support of the tube on each fixed end panel but also for projection or cantilever beyond the device for fin placement. Perhaps a longitudinal adjustment would be a nice feature. Unfortunately, every additional feature takes time and thus increases the cost.

Source: http://www.fliskits.com/products/rocketkits/micromaxx/mmx_body.htm

Today I went to a REAL Watering Hole with my son in his boat: Lake Texoma, 89,000 acres of clear, blue water and NO COMPUTERS!
 

tmacklin

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Like CW & Krurgon, I'd be interested depending on the price point.
For us MicroMaxxer's we would need a jig that would handle Tubes from T2 (.246" OD) to prehaps as large BT-50 (.976" OD). To be perfectly Honest BT-5, BT-20 and BT-50 size models are ONLY 3,4 & 5 motor clusters. Most micro powered models BT-5 and Up are not very good flying machines.
The rest of our range would be T2 (.246") T2+ (.281") MMX minimum motor size, T3 (.375"), T4 (.448"), with BT-5 (.544"), BT-20 (.736") and BT-50 Only of minor importance.

More important I my mind; Many of our Micro Rockets are no more the 4.0" long. Some with fins smaller are less then 1/2" Root to tip so some very small Alignment angles would be required. Many of our models use fin materials as thin as .005" and .010" Waferglass (super thin G10). Styrene and Lexan fins down to .010" and as thick as .030", Standard 1/64 and 3/64 3ply aircraft Plywood, and Balsa and Basswood 1/20th" .032" and 1/16" is just about the max.

I've looked before for Tiny Brass, Stainless Steel or Aluminum 3/8" or under Angles rigid enough for such use without much luck.

I've looked at fabricating a Micro Guillotin type fin jig a couple times in the past just for fun. My inclination would be to fab. the either thing from all aluminum, Stainless steel or possibly a high strength laminate. Woods; even Aircraft birch Plywood would seem to be to thick for such a project. The alternates materials however I fear would make this little machine far to expansive to purchase????

I'll keep my eye on this thread, If you need any specific specs on materials or processes used please let me know.
Thanks John. The concerns you raised are the same concerns I've had since the idea of a "Mini-Guillotine" first came up. What works well at the large scale does not always translate to the small scale, and vice versa. It's why watchmakers tools are so expensive!
 

tmacklin

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I have been thinking, sketching and formulating my ideas toward this challenge and hope to produce a prototype soon. Stay tuned sports fans!
 

tmacklin

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John, AKA Micromeister,

Am I correct in the assumption that the smallest outside diameter of any Micro-Maxx type rocket air frame would be 0.246 inches?
 

mwtoelle

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AFAIK, BT-2 is the smallest body tube that is commercially available. Generally, most of the Micro-Maxx rockets that I have seen use either BT-2.5 (0.281"), BT-3 (0.375"), BT-4 (0.448") or BT-5 (0.544") tubes for a single motor model. Micro-Maxx clusters can BT-20 or BT-50 tubes, but the drag penalty is high for Micro-Maxx motors. The limited power of these motors tends to favor lighter and skinnier models. Compared to standard Estes/Quest models, you really need additional tools such as modelling tweezers and glue applicators (the leftover red tube from a canned air can works really great.)
 

tmacklin

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AFAIK, BT-2 is the smallest body tube that is commercially available. Generally, most of the Micro-Maxx rockets that I have seen use either BT-2.5 (0.281"), BT-3 (0.375"), BT-4 (0.448") or BT-5 (0.544") tubes for a single motor model. Micro-Maxx clusters can BT-20 or BT-50 tubes, but the drag penalty is high for Micro-Maxx motors. The limited power of these motors tends to favor lighter and skinnier models. Compared to standard Estes/Quest models, you really need additional tools such as modelling tweezers and glue applicators (the leftover red tube from a canned air can works really great.)
Fliskits shows a BT-2 tube as having an outside diameter of 0.246 inches. Their MMXII motors have an OD of 6mm, or 0.236 inches if my math is correct. So based on that data, I will size the minimum opening for the Mini Guillotine to be 0.243 inches. I hope to begin fabrication of this little gem tomorrow. Thanks for your input.

http://www.fliskits.com/products/01prod_fs.htm
 

Micromeister

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Fliskits shows a BT-2 tube as having an outside diameter of 0.246 inches. Their MMXII motors have an OD of 6mm, or 0.236 inches if my math is correct. So based on that data, I will size the minimum opening for the Mini Guillotine to be 0.243 inches. I hope to begin fabrication of this little gem tomorrow. Thanks for your input.

http://www.fliskits.com/products/01prod_fs.htm
Sorry for the late reply, been busy working on several Scale Micro models so haven't been on-line much last week.

The Smallest Airframe tube for Micro Maxx motors is T2+ (.281" OD .255" ID). T2 tubes are .246"OD, .220" ID Which make EXCELLENT motor stops and shoulders but you can NOT get a MMX motor in them.
 

tmacklin

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Sorry for the late reply, been busy working on several Scale Micro models so haven't been on-line much last week.

The Smallest Airframe tube for Micro Maxx motors is T2+ (.281" OD .255" ID). T2 tubes are .246"OD, .220" ID Which make EXCELLENT motor stops and shoulders but you can NOT get a MMX motor in them.
Thank you very much. This information is critical in establishing the dimensions of the minimum opening. I would be working on this today but the heat, humidity and my sore feet prevent it.
 

dhbarr

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Might be just me, but I very much dislike operating tools at the extreme end of their stops.

OD of the MMX motor, .236 would be the number I'd like. Why would I want to hold an MMX wrapped in parchment or .75oz glass, no idea.

Would I ever want to attach fins directly to an MMX casing? Maybe for a dummy upper stage.

Disclaimer : I have less experience at this scale than almost anyone.

PS: This thing could probably ship as a single 8.5x11 mostly-routed sheet plus a tube of hardware.

PPS: Put me down for the first production run, whatever you decide :)
 
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tmacklin

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My original concept for the Guillotine Fin Jig was a tool that would adjust for a range of body tube diameters then in production (2011) and resulted in a device with a range from BT-5 through BT-80. That original design has evolved over time and I now produce two versions for Apogee, one that rages from BT-5 to 3.00 inches and a larger version that ranges from 1.75 to 6.125 inches. (I also make a mid-sized version which I sell directly through my website) These all function exactly alike, i.e., the tool is adjustable to the OD of the tube desired and the alignment rails adjust and center the fins, one at a time, relative to the tube. Unfortunately, "going small" presents a number of problems that "going big" does not, the first of which is the size of the average human hand.

Whether or not I go into production of these will depend upon reaction to my as yet un-built prototype and the size of the marketplace. I anticipate a kit which will consist of two fixed end panels, two sliding end panels, two side panels and a bottom panel. The fin alignment rails will still be of aluminum extrusions, but smaller and with a different configuration. I need a bit of time to do all this, and Texas in summer is not helpful!
 

tmacklin

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Today was much too hot to do anything in my shop so I went with "plan B", stayed in the air conditioning and fabricated a full size prototype from 3/16" foamboard and 1/4 x 1/2 inch balsa scrap. I'm short some 1/16 x 1/2 x 3/4 inch aluminum angle for the rails. Here are a couple of pics next to the original sized version. The first pis shows a 1/4 inch OD tube in the jig; the second pic shows a BT-56 in place and a part of the alignment rail which will ultimately support a 1/8 x 1/2 aluminum flat that will cantilever beyond one end. The end panels are 4 inches square and the side panels are 4 inches high x 5 inches long, which leaves 3 inches clear between the fixed end panels. It could be made to any length but making it much shorter will be at the sacrifice of longitudinal alignment. (think rifle vs. pistol sights) I'll post more pics once I've fabricated the two piece rails.

IMG_1380.jpg


IMG_1382.jpg
 

tmacklin

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Might be just me, but I very much dislike operating tools at the extreme end of their stops.

OD of the MMX motor, .236 would be the number I'd like. Why would I want to hold an MMX wrapped in parchment or .75oz glass, no idea.

Would I ever want to attach fins directly to an MMX casing? Maybe for a dummy upper stage.

Disclaimer : I have less experience at this scale than almost anyone.

PS: This thing could probably ship as a single 8.5x11 mostly-routed sheet plus a tube of hardware.

PPS: Put me down for the first production run, whatever you decide :)

Your concerns are well founded and will be taken into account. At this juncture, I'm pretty sure the range of the tool will be from 0.221" to 1.414" which will accommodate body tubes from T2+ to BT-56.
I have created prototype fin alignment rails which I will photograph and then post pictures later today. As for "price points" they remain to emerge.

Thanks for your interest.
 

tmacklin

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And the pics:

IMG_1384.jpgIMG_1385.jpgIMG_1386.jpgIMG_1387.jpg

The fin material/gauge shims shown here were made from 1/32" aircraft birch. The fin shown is a clipped delta and measures 1 inch from root to tip with a 1 inch root length and a 0.50 inch tip length. The closthes pins are used to clamp the various parts together in lieu of screws and nuts, and would not be part of the finished product. In the last photo, you can see a 1/4" ID launch lug having an OD of 9/32 inch (0.281") that I slipped over the 1/4 inch aluminum tube. The T2+ tube is 0.281" OD.

A microscope will NOT be part of the final package!
 
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tmacklin

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Very nice!
Thanks! There are some minor things that need to be worked out and I am in contact with Nat Kinsey about these items. I realize that these diminutive models are most often short in length and this presents a problem that is best remedied by the use of a tube coupler, extension tube and removable tape. Having the support/gauge points further apart tends to minimize any longitudinal error and I suspect that most of you micro-builders are also scratch builders as well..yes, yes?
 
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