MMX Launch Rack

[Micromeister]

Looking at it from the top, though, there was a slight problem. The grips on the clamp were just a touch wider than the slot. For the ultimate plan, they needed to fit flat within the slot.

John:
I hate to bring this up but Where are you going to connect the clips? if the plug is sitting the way your showing it you'll have to use some sort of exposed contact place in the bottom of your opening which will quickly get crudy with exhaust residue and other trash preventing good contact after only a few flights. This was/is one of the major problems with the original silo launcher bases. You'll need to provide clearance to get your systems micro clips attached to the plugs contact points by simply turning the plug 90° to the support arm and allowing the contacts to hang exposed. I've found a tapered slot holds the plug igniters frimly enough NO external clamping is needed to insure solid holding during use or ignition. and the tapered slot also doubles as a setting part for other type igniters as well.
Hope this helps a little.

 

[JAL3]

John:
I hate to bring this up but Where are you going to connect the clips? if the plug is sitting the way your showing it you'll have to use some sort of exposed contact place in the bottom of your opening which will quickly get crudy with exhaust residue and other trash preventing good contact after only a few flights. This was/is one of the major problems with the original silo launcher bases. You'll need to provide clearance to get your systems micro clips attached to the plugs contact points by simply turning the plug 90° to the support arm and allowing the contacts to hang exposed. I've found a tapered slot holds the plug igniters frimly enough NO external clamping is needed to insure solid holding during use or ignition. and the tapered slot also doubles as a setting part for other type igniters as well.
Hope this helps a little.

I think you see part of the way I am headed. There will be some exposed brass but it will be a double system; both in place but use the one that fits the situation. I have given some consideration to the gunk buildup but am still working on it. My hope is a simple way to deal with it.

I like the taper idea. I remember seeing something of the sort but forgot about it. I wasn't actually thinking about that when I had my idea for the leads but it can simple be incorporated. I need to find the brass though. Radio Shack apparently doesn't handle that type of thing.

 

[Micromeister]

I think you see part of the way I am headed. There will be some exposed brass but it will be a double system; both in place but use the one that fits the situation. I have given some consideration to the gunk buildup but am still working on it. My hope is a simple way to deal with it.

I like the taper idea. I remember seeing something of the sort but forgot about it. I wasn't actually thinking about that when I had my idea for the leads but it can simple be incorporated. I need to find the brass though. Radio Shack apparently doesn't handle that type of thing.

You might want to consider Copper or brass adhesive backed foil tape. I use copper alot with Night flight models. it can be soldered to is heavy enough to take a little abuse and light enough to wrap around things where needed, I recently saw a roll at Lowes in the electrical section, got mine from the usualy source..mcMaster.
I can't begin to tell you how much of a problem exhaust residue is. on slightly humid days it'll make getting good contact a real headache.
You can see the tapered cutout on the Drawing I posted back a few posts. it should print out full size.

 

[MarkII]

I gotta agree with Micro on this. Before I started taking the plastic igniters apart, I used a piece of plywood with a slot cut into it glued to a launch lug.

I clipped the wires to the launch rod with a clothespin so there was no strain on the leads.

You must get better QMX plugs than I do. In all of the ones that I have, just the very tips of the leads are visible. Barely enough to touch a wire to, let alone attaching a clip.

I don't need pliers to separate the two halves of the plug housing. They aren't that hard to get apart, and my thumbnail works just fine for that task. I usually don't do it until I am at the pad and I'm preparing to insert the igniter. It's easy and I have been doing it for practically as long as I have been flying micros. I suppose that I could leave the igniters in their housings and just cut away a bit of material at the bottom to expose more of the leads, but at that point, separating and dispensing with the plug housing seems to be the easier solution.

So, do you guys actually launch your micros out at your clubs' ranges? I have trouble imagining what that is like. To my eyes, Micromaxx represents a style of rocketry that is more informal, more intimate and more spontaneous than other forms of model rocketry, something that seems to have been deliberately scaled for flying in the front or backyard or in the neighborhood park. Taking micro rockets out to fly at a 200-acre sod farm would feel a little bit odd to me. I have never flown in any 1/8A competition events, though (nor have I ever witnessed any events in that motor class, either), so maybe it's different when they are flown at a meet.

MarkII

 

[BobH48]

So, do you guys actually launch your micros out at your clubs' ranges? I have trouble imagining what that is like.

I do take them occasionally, mainly at the smaller fields. I can launch MMX rockets in my side yard but Micro gliders and clusters get launched at a club launch

 

[billspad]

I do take them occasionally, mainly at the smaller fields. I can launch MMX rockets in my side yard but Micro gliders and clusters get launched at a club launch

I think we have at least a couple of MicoMaxx flights at all of our launches. I can launch them in my yard but not recover them. Too many trees.

 

[jflis]

I think we have at least a couple of MicoMaxx flights at all of our launches. I can launch them in my yard but not recover them. Too many trees.

Heck, more often than not we set up pad 11 for micro's anyway

Oh, by the way I hope to have a new micro or two for Saturday's launch. Let's hope the current forecast moves the rain to Sunday...

 

[Micromeister]

Mark:
One of the very easiest mods to the ol'e plugs is to snap the little plastic tips the contact wires are bend around thus exposing the little half loop at the bottom of the plug. There's always more then enough to grab with smooth jaw micro clips. Alligator clips don't work worth a darn on any igniter, tho I've seen several of the Micro flying guys in the Vikings club use them with MMX plugs often.

I have to disagree in your assessment of micros as being somehow different or "out of place on a 200acre sodfarm Launch".
I believe Micros will at some point become the mainstay of the hobby; At least here on the east coast where those 200acre launch sites are becoming harder and harder to find. I Want everyone flying micros ever single time there is a Model Rocket Flying event of anykind. We had a number of micros flown at NSL this summer. Two events at this last Naram-51 were either 1/8A specific or well suited to micro models in peanut scale.

Both clubs I'm connected with; Narhams (oldest section in the country) and Vikings (one of the newer "reborn" sections) have increasing numbers of particapation by members flying Micros at every club launch and a fair number for sanctioned competitions as well. I've been know to fly Micros in standard competitions just because I didn't intend to enter or just a last minute on the field decision. Often using Micro's in any of the Spot landing events, Random Duration, Scale, PMC or any of the Craftsmanship events. Having my entire fleet with me give me all those options We try to include an 1/8A event in a club scheduled section, open or regional meet each year, or at least a "Fun Fly" event with them.

As mentioned in my earlier post to John there should be absolutely NO difference between flying Micro Models and any other form of model rocketry. With the exception of the diameter of the Launch rod, just like LMR's and HPR everything else remains the same. Most of us maxx'ers have no trouble flying a Micro model from standard Club style Racks or satellite pad launchers.

As others have commented; Being further way (Our LRP range setups use 50' leads) from the model actually helps along with all the extra eyes aid in tracking and recovery.
Rarely anymore do I even take standard or LRM's out to our monthly club launches unless its for a special event (Night Launches) or I have a specific model I want to fly or requried for a specific competition event, but DO fly anywhere from 10 to 15 or more micros from my fleet every month. With the slip-over rod micro pad add-ons there generally isn't any problem with line waits or backing up other flyers on the ranges and we generally have some pretty large crowds of sport flyers. Both clubs use multi rack ranges with away satellite mid and hpr pads, giving anywhere from a minimum of 8 to 18 available launcher locations. Generally my tripod everyday workhorse Micro launcher base is on site as well so we also have access to micro Tower's, Pistons, and multi rod set-ups for Gliders and relay ignitions system for micro clusters. If it's done with standard size models and I'm on the field it can be flown with Micros.
Micros get just as many Ohoo's and Ahaa's as any other type or size models and sometimes greater since some spectators have NO Idea how well these little models fly.

 

[billspad]

Let's hope the current forecast moves the rain to Sunday...

I don't care what the forecast does, it's the actual rain that I want to move to Sunday.

 

[MarkII]

I have to disagree in your assessment of micros as being somehow different or "out of place on a 200acre sodfarm Launch".
I believe Micros will at some point become the mainstay of the hobby; At least here on the east coast where those 200acre launch sites are becoming harder and harder to find. I Want everyone flying micros ever single time there is a Model Rocket Flying event of anykind. We had a number of micros flown at NSL this summer. Two events at this last Naram-51 were either 1/8A specific or well suited to micro models in peanut scale.

Oh, no... I guess I didn't make myself clear. I was talking about how I see them, not trying to tell anyone else how to fly them. In my area, many of fields that can be used as "rocket ranges" are just relatively small open areas in the woods, little holes in the vast forest. Micromaxx rockets are the easiest type to fly in them, and the flights just seem to be more dramatic and riveting in those places. Seeing them blast off against a solid backdrop of tall pines is just too cool, and watching them strive to reach that patch of freedom high overhead... well, that has its own kind of drama. Imagine listening to a choir that is singing Gregorian chant in a great old cathedral, and then imagine listening to them sing out in a pasture. A big part of the experience is lost in the more open setting. That's kind of how I see Micromaxx flying. Come on, you know that I'm a big fan of these little wonders; it's the first stuff that I flew after I became a BAR. I readily encourage anyone to fly them, and I'm not about to try to tell someone that they can't fly micros at their club launch. (I flew a couple of mine at a club launch for the first time earlier this summer. I would have flown some at NARAM, too, if I had remembered to grab that box as I was packing the car. I brought the motors and I brought the GSE; I just didn't bring the rockets. <sigh> )

MarkII

 

[MarkII]

BTW, at our most recent section meet/sport launch last Sunday, we had a total of 5 fliers, which was a pretty good turnout. By the time that I got down there, though, there was just the CD/RSO/LCO (who was all done flying for the day), a new club member who was only flying sport and me. The other flier left about an hour after I got there, though, so I had the pad all to myself. Being able to fly with other people in a big field was worth the 2.5 hour drive each way; I had a great time.

OK, back on topic...

MarkII

 

[JAL3]

OK

I have a question for y'all out there.

I
m ooking for some sheet brass or copper, prefferably brass. I want it to be thin enough to bend and have some spring to it, like is seen is the clips of some battery compartments.

I have tried Radio Shack and 3 different hardware stores and have gotten noting but offers of foil or blank looks.

WHere does somebody go to get that type of material and does it have a "proper" name?

 

[MarkII]

Brass strip stock. Check with your local hobby shop. You can also get it online from a variety of sources.

MarkII

 

[Micromeister]

Brass strip stock. Check with your local hobby shop. You can also get it online from a variety of sources.

MarkII

Yep! what Mark said: Your Local Hobby shop or well stocked Micheals. Generally it's with or next to the Music wire display.

Some hardware stores (Ace around here) carry brass shim stock as well in sheet form.

If your looking to purchase on-line: Micro Mark has a complete line of Thin metals stock in sheet, rod and tube. As does Small Parts Inc.

 

[JAL3]

Thanks for the pointers. I'll make another stab at it.

 

[Micromeister]

BTW, at our most recent section meet/sport launch last Sunday, we had a total of 5 fliers, which was a pretty good turnout. By the time that I got down there, though, there was just the CD/RSO/LCO (who was all done flying for the day), a new club member who was only flying sport and me. The other flier left about an hour after I got there, though, so I had the pad all to myself. Being able to fly with other people in a big field was worth the 2.5 hour drive each way; I had a great time.

OK, back on topic...

MarkII

5 Flyers... at an August Launch...Wow! You guys must Really be spread out up there.
We generally have more flying then that at February Launches. Most others average 25 to 50. sometimes more during the warm months flying season, tapering off to a dozen or so during the cold winter months.

Are there that few people flying Mod-rocs in New York or are they all sport flyers doing it on their own? Which is exactly my point.. I'd sure like to see more access to the Micro Models Line(s). If more stores and Hobby Shops had access and/or carried Micro models, parts and motors I'll bet you'd see a bigger turnout at publicized Sport launches or Group launch opportunities because they can be flown so well from smaller fields.

Smaller However is really relative to the TYPE of micro's being flown. PD, Gliders, Flex-wings & Helicopters really need the largest fields we can find. I've yet to return a micro Flex-wing. Most competition type micro-PD models 12-20" 1/4mil mylar chutes float away. Helicopter Durations (HD)type model, if you have even a slight breeze a 45 or more second flight on even fairly large fields are not recoverable. The week before naram I flew away 4 different 1/8A HD models during "testing". It's very frustrating to have to keep rebuilding new models and HOPE the darn things works properly the first time without a test flight. Yet another reason I no longer really compete...it's just to much like work, besides the LUCK factor or "lack there of" usually rules the day... as Chris Taylor often quips..."I'd rather be Lucky than all that Good".... Oh yes; do I fully hear & understand. LOL!

Hope your gang picks Up plenty of new flyers... It's a lot more fun flying with a bunch folks.

Back to the building of a Club Micro Rack or club micro launchers... I guess we never really determined exactly what John is actually building toward?
Can you fill us in John? Are you working on a micro Rack system or add-ons to your clubs current racks?

Edit: John: I was giving the brass wrapped slot crud built-up some thought last evening. While I maintain you'll have to content with issues on the field with this approach particularly during high humidity days, If you leave the area at the bottom of the cutout opening large enough for a Q-tip it should be possible to swab off the contacts every so often during the day to keep them operating. In fact If I were doing a notched system like that i'd have only a short say 1/4" wide retaining band on both sides of the notch at the top just short of where the finger tabs on the plugs hit the top of your support arm, allowing the plug or other type igniter to slide between the bands with the wire contact points touching the brass.
Another consideration about your wrapped brass contacts, they need to float a tiny bit as the plug contact wires are not all exactly the same. Ya might want to consider using very thin brass that can be bent slightly under 90° to allow it to stand up slightly in the bottom of the notch. This also requires those retainer bands or spring clamp to hold the plug in the down postions ensuring contact on both contact brass strips...... See why this type of attachment isn't all that positive or reliably?
Hope this helps

 

[JAL3]

5 Flyers... at an August Launch...Wow! You guys must Really be spread out up there.
We generally have more flying then that at February Launches. Most others average 25 to 50. sometimes more during the warm months flying season, tapering off to a dozen or so during the cold winter months.

Are there that few people flying Mod-rocs in New York or are they all sport flyers doing it on their own? Which is exactly my point.. I'd sure like to see more access to the Micro Models Line(s). If more stores and Hobby Shops had access and/or carried Micro models, parts and motors I'll bet you'd see a bigger turnout at publicized Sport launches or Group launch opportunities because they can be flown so well from smaller fields.

Smaller However is really relative to the TYPE of micro's being flown. PD, Gliders, Flex-wings & Helicopters really need the largest fields we can find. I've yet to return a micro Flex-wing. Most competition type micro-PD models 12-20" 1/4mil mylar chutes float away. Helicopter Durations (HD)type model, if you have even a slight breeze a 45 or more second flight on even fairly large fields are not recoverable. The week before naram I flew away 4 different 1/8A HD models during "testing". It's very frustrating to have to keep rebuilding new models and HOPE the darn things works properly the first time without a test flight. Yet another reason I no longer really compete...it's just to much like work, besides the LUCK factor or "lack there of" usually rules the day... as Chris Taylor often quips..."I'd rather be Lucky than all that Good".... Oh yes; do I fully hear & understand. LOL!

Hope your gang picks Up plenty of new flyers... It's a lot more fun flying with a bunch folks.

Back to the building of a Club Micro Rack or club micro launchers... I guess we never really determined exactly what John is actually building toward?
Can you fill us in John? Are you working on a micro Rack system or add-ons to your clubs current racks?

Edit: John: I was giving the brass wrapped slot crud built-up some thought last evening. While I maintain you'll have to content with issues on the field with this approach particularly during high humidity days, If you leave the area at the bottom of the cutout opening large enough for a Q-tip it should be possible to swab off the contacts every so often during the day to keep them operating. In fact If I were doing a notched system like that i'd have only a short say 1/4" wide retaining band on both sides of the notch at the top just short of where the finger tabs on the plugs hit the top of your support arm, allowing the plug or other type igniter to slide between the bands with the wire contact points touching the brass.
Another consideration about your wrapped brass contacts, they need to float a tiny bit as the plug contact wires are not all exactly the same. Ya might want to consider using very thin brass that can be bent slightly under 90° to allow it to stand up slightly in the bottom of the notch. This also requires those retainer bands or spring clamp to hold the plug in the down postions ensuring contact on both contact brass strips...... See why this type of attachment isn't all that positive or reliably?
Hope this helps

I guess I missed this when you posted it. In any event, some progress has been made that I just have not had a chance to write up.

My goal is to build a dedicated rack for the club. This is to be the first of several, intended for differing special needs. I hope to have the same base on all, same bolt alignment and just be able to switch out the top surface.

I actually have a crud cleaning plan that I hope will not be too onerous. Time will tell.

 

[JAL3]

To provide electrical contact, I intended to use a pair of brass pieces, one on each side of the launch head. each would be primarily vertically oriented so that a naked or standar ingniter could be set in place with one lead clamped to either side. I also intended to fold a small piece of brass over the top to catch the leads on the classic MMX igniter.

I went into Autocad and drew up a plan for the brass pieces assuming that I would be using 1/2" wide brass. The lines for folding and cutting were marked interchangeably. A copy was then printed, cut out and taped to a piece of 1/2"x0.016"x12" piece of brass.

 

[JAL3]

A cutoff disk on a Dremell tool was then used to cut the piece to length and slice the part that would be folded back.

 

[JAL3]

A pair of pliers was then used to make the bends and folds. The folds were not completely bent into shape under the theory that some finagling would be needed and I wanted to fatigue the metal as little as possible.

 

[JAL3]

An identical piece was then cut and formed and the pair was test fitted into the head.

 

[MarkII]

5 Flyers... at an August Launch...Wow! You guys must Really be spread out up there. ...
Are there that few people flying Mod-rocs in New York...?

In our corner of the state, apparently so. In all of northeastern NY (the portion that is north of the Hudson valley, east of Utica and south of the Canadian border) there are six (6) of us who regularly attend launches and club meetings. I am the only NAR member in the entire Adirondack region. This is the number after many years of concerted outreach throughout the region. I joined in 2006 and I am the most recent addition to the "hard core" group. Rocketry still has some pretty ugly connotations to many people around here, eight years after the event.

OK, enough about that. Let's get back to John's project.

MarkII

 

[JAL3]

Soldering is not one of my strong skills, and that's putting it kindly. Even so, I felt obligated to provide the electrons with a path to get to the brass contacts. I took a length of speaker wire, stripped the ends and then soldered a lead to the back of each of the contact plates.

 

[JAL3]

In order to accommodate the solder on the backs of the contact plates and allow them to lie flat, I had to excavate a cavity on either side of the head. It was done by trial and error with an ambiguous head on the Dremmel.

 

[JAL3]

Since this was merely a proof of concept prototype, I did not take the trouble to fasten the plates to the head in a "good" manner. Instead, I just epoxied them into place and clamped them to set. This proved to be a mistake since some of the epoxy developed and unhealthy relationship with the clamp and the removal of said clamp distorted things.

 

[JAL3]

Several tests were made with the prototype and I found that the concept did work but that there were some problems with execution. Aside from the not so durable balsa used as the head, the method of attaching the wires to the plates and the plates to the head were also problematical. As I considered how to deal with these issues, I turned my attention to the "guts" of the project.

My intention all along was to develop a series of racks for various types of rockets my club may fly. I wanted to standardize as much of the design as possible. I had decided early on that each rack would be mounted on an identical steel sawhorse. To that would be fastened a "box" that would contain whatever wiring was needed and on the "box" would be mounted the individual launch heads. After looking at lots of different options for the "box", I decided to try using NEMA type 1 electrical troughs. For the MMX rack, I ordered a 4"x4"x48" trough with a hinged cover and a pair of endcaps to go with it. I specified that I did not want knockouts.

 

[JAL3]

I wanted to go ahead and prime the box and knew that my normal Kilz primer would not be a good choice. Based on some advice, I purchased Dupli-Color automotive white primer and went to work spraying. I quickly learned that while the primer adhered well, a lot was needed for full coverage. I emptied a can and still plenty left to go.

 

[JAL3]

Rather than spend more in primer than the box cost, I decided to brush on some gray primer made for metal applications. I bought a gallon since I have several projects on which to use it and because it was not available in smaller sizes. I brushed on the first coat and let it dry overnight.

 

[JAL3]

The end caps were painted as well.

 

[JAL3]

The first coat of gray primer was rather streaky (but much better over the surfaces that had received the white spray primer first) and a second coat was applied to all the pieces. It came out much better.