A few of us Maxxer's fly Clustered Micro Max models on a semi-regular basis. Most in my Micro Fleet are 2 or 3 motor..with only a few 4 to 8 motor clusters.
Normally two motor models fly just about the same as a single motor...just twist the leads together and attach clips as usual.
For 3 motors and Up I Personally always use a Rangebox Relay with a 7mAh gel-cell at the pad. I'm wondering what others use to get all motors thrusting?
Recently I've been running Quest Q2 igniter tests and had a run of very poor cluster ignition results even on 2-motor clusters. Normally I'd use my own cluster Igniters but wanted to see if the Q2's could or would be as reliably as the ones I dip myself. Hands down the answer has been NO. I'm curious to see what other folks are doing to fly clustered micros?
I'm a great believer in Nichrome or pyrogen/propellant contact in any and all Micro Maxx motor ignition situations single motor to 9-MMX-II and 12-MMX-I (Full A power) motors as the largest Igniter set-ups I've personally launched.
My feeling is any cluster over 2 motors has to have pyrogen tipped igniters. Why? because our tiny models get moving so quickly if there isn't a good amount of play in the clip wires and a very quick pyrogen heating the BP, one or some of the motors never have a chance to come up to temp for ignition before the igniter is ripped from the nozzle at or just after first motion. To say Micro Clusters Teleport is sometimes an Under statement.
For many years I've used a Al-AP-Epoxy pyrogen mixture that is slightly slower then the stuff on Estes igniters giving them a split second longer to heat all motos in my standard size & Upscale D12 powered models. Used in much smaller tipped 30ga igniters fabricated specifically for Micros this slight delay seems to help only with the heavier BT-20 & BT-50 size models. Again our Super light weight T5 and below body models get going in an awful hurry! I'm now looking for a slightly faster ignition pyrogen. Soon i'm hoping to try a Nitrocelluose/pyrodex very thin mixture to keep the tip mass as small as practical. Even then I think it may be necessary to clip or grind down the outside edges on Q2's at the crimped bridge wire to allow our new tip to completely enter the MMX-II nozzle. I'm sticking with the older 30ga dipped igniters for the Old Nozzle holed MMX-I's.
To ensure Pyrogen/Propellant Contact I'm gently bending the bridge wire tips on all igniters about 10° to help inside the motors. Wadding balls tamped between the leads seems to be a help here rather then on one side or another of both leads. secured with a small piece of 1/8" masking tape.
I'd sure like to see or hear what you other Clusted Micro flyers have come up with the reliably get these little jewels flying?
Anyone out there experimenting with micro igniter pyrogens or other cluster ignition techniques?
I've done 4 (the rocket with the white fins) and 5 (the Little Joe) using this circuit board and the old igniters. It's reliable but getting all the igniters lined up with the nozzles can be a bit challenging.
I've been working on my MMX cluster technique while my club has been flying off a smaller field. For the record, I'm flying two motor clusters. I'm using a Quest pistol-grip controller with a drop battery cable. My battery is 12 volt with enough mAh to light 4+ motors. I am not using a relay box (yet).
Best success was with the Quest Q2 igniters. I use slivers of balsa wood for plugs and a small strip of masking tape to secure the business end. The leads were twisted together. I lick my fingertips and get the twisted leads as moist as possible before attaching the micro clips. This seems to up the success factor. I did some static tests a while back and tried a dab of vaseline on the leads (used for positive connection on the electric chair BTW). This worked but I have not tried this in an actual flight attempt.
My last launch I used raw Nichrome wire. I found there was enough delay (even with a fully charged battery) to not light both motors simultaneously. I liked using the Nichome however. It is a bit easier to prep the motors. If I pursued this end to light clusters I would build a relay box and/or look into dipping my igniters.
One fellow who flies with my club has experience with dipping his igniters. He shared his recipe once. It involved dissolving Ping Pong balls in Acetone and adding some BP. I should add he used this to get composite motors going but I liked the Ping Pong ball angle.
I recently got some advice from another experienced flyer regarding MMX ignition. It involved the use of a tiny drill bit to clear away any clay in the nozzle that may prevent positive contact between the grain and igniter. I found a small bit in my Dremel box that seemed perfect for this but have NOT tried this technique out yet.
I have to agree 100% that one motor lighting earlier than the other can kill a successful cluster ignition. No matter how careful you prep.
Bill the circuit board base thing is pretty interesting. Was the base circuit board used to make twisting or connecting all the leads easier? Do you solder or just twist the leads together under the board? How often does the board have to be replaced? I can see where the method would get a bit fussy with five and up
HB: Generally bare nichrome is fine with 2 motor clusters. All that excess 22ga fine controller wire sure slows the heating process. It'd be a good Idea to either fabricate or purchase a relay box or rewire the pistol grip with 16/2 lamps cord to reduce the resistance over that 15 or 20foot run. If you add the relay no change would be needed in your controller leads. I'm using the exact same setup, when not using one of the Clubs HD multipad controllers.
Your club friend is creating Nitocelluouse lacquer by melting Ping Pong balls in Acetone. That's what I'm using as a pyrogen mixing base but substituting Pyrodex for BP since we can use Pyrodex igniters without a leup. Haven't really tried the new dipped Q2's as I still need to file or grind down the bridge wire crimps on the few I've made up to better fit the MMX-II motor nozzles. On a few earlier, different mix attempts I had a hard time getting the pyrodex mixture to adhear to the nichrome bridge wire or the stuff was too thin drying in a clump at the tip or side in a ball to large to go in the nozzle. Looks like getting the viscosity right in the liquid form is almost as important as getting a mixture that will ignite quickly.
Yeap I use I believe a 1/16" drill bit on all micro motor cluster. Do the same with larger bits with 18 & 24mm motors as well if used in clustered applications. Making sure the Propellant face is clean is almost as important as maintaining pyrogen-Propellant contact between Igniter tip and motor.
First Motion will always be a concern regardless of model or motor size. The larger and heavier the model the less likely first motion will be a factor...with Micor's minimum diameter and T3 body models seem to need longer lighter relay or controller leads without increasing the resistance in the wire. I've been experimenting with 18 & 20ga stranded copper wire, 18" long leads loop coiled under the model (Not under the motors) to give a bit more leeway at first motion ignition. 18 seems to be working OK...20ga has not as yet but i've only had two attempts with each of these with 4 motor cluster models.
I've been thinking for cluster igniters I may try a bit longer 1-1/2" length in 32ga (.0080") dia Nichrome. Home bent with the new NCL/pyrodex pyrogen tip to help lighten the twisted igniter load. I believe 32ga, is the gauge used in the micro Q2 leads.
Hopefully have some results from a few of the options next week.
Last edited by Micromeister; 7th June 2012 at 04:26 PM.
Bill the circuit board base thing is pretty interesting. Was the base circuit board used to make twisting or connecting all the leads easier? Do you solder or just twist the leads together under the board? How often does the board have to be replaced? I can see where the method would get a bit fussy with five and up
The top of the board has socket things that the igniters go into. No twisting necessary because all the sockets are wired together under the board like this
The motors are held up high enough that the exhaust just dirties the board a little. I don't remember how many times I've used it but it's still the original.
When I get around to it I'm going to solder some of those sockets onto stiff heavy gauge wire co they can be positioned under the motors more easily.
I decided to try the socket and wire idea before I forgot about it again. Here's what I came up with.
Those are old style igniters that have been shelled. No toothpicks, slivers of balsa or balls of wadding necessary. Just slide the rocket down. It worked well right after I was reminded to hook the clips up. Jim Flis got a couple of good shots of it in flight. I got a nice picture of smoke. I'm going to order more sockets to see if I can do 4 motors in a tighter cluster.
Last edited by billspad; 11th June 2012 at 04:05 AM.
Are they the .0100" sockets Bill?
Very nicely done.
That is very similar to the sit up I use for single igniters with the clips soldered to coiled 20ga stranded copper wire so the igniter can be tilted and moved to any postition necessary to allow the igniter to slide into the nozzle letting the coiled wire support the model.
had a chance to dip and static test a few Q2 igniters in the NC-Lac/Pyrodex mixture yesterday. Wow are they fast even with only a super thin coating. tried 2,3 & 4 igniters twisted Pos. Neg. style with and without relay. All combinations Seem to heat and ignite almost instantly and together. Next test will be in live motors.
I Good test will by my recently clursted Mudwasp with three inline motors. More then likely I'll give it a test Next Saturday at Ecrm-39.
I don't think so. The wire from an old style MicroMaxx igniter is around .019 and it fits in the socket. A Q2 igniter will also fit. The sockets are on a strip with .10" centers if that's what you mean.
Not exactly Bill. 30gauge Nichrome is .0100" dia. which is what I've been using in leu of the old Plug type igniters. I've been using a Mill-Max Socket that is designed for .0100" wire leads with my Micro Piston launcher and a few other applications I was wondering if you were using the same type socket? apparently not.
While I was looking for some Quest Q2 bare igniters to dip I found a bunch that came with a couple of the later SVSS's and a box of prototypes early Q2's Mr. Stine sent me a few years back to experiment with. I was surprised at the difference in lead wire gauge. the Prototypes were .009" diameter while the currently supplied Q2's are a whopping .015" diameter. This is why the newer Q2's don't really fit inside the nozzle as we would like. I'm dipping some of each. should have some info to report later this week or early next on weather the new thicker lead Q2s can be dipped the the crimped edges ground to fit in the MMX-II motors.
Last edited by Micromeister; 13th June 2012 at 09:29 PM.
Not exactly Bill. 30gauge Nichrome is .0100" dia. which is what I've been using in leu of the old Plug type igniters. I've been using a Mill-Max Socket that is designed for .0100" wire leads with my Micro Piston launcher and a few other applications I was wondering if you were using the same type socket? apparently not.
I tried a piece of 30 gauge. Way too loose. I got a reasonable fit by bending and straightening the end of the wire. The kink was enough to make contact but I'd worry about reliability. If I ever use up the pile of old igniters I'll have to try those .01" sockets.
I tried a piece of 30 gauge. Way too loose. I got a reasonable fit by bending and straightening the end of the wire. The kink was enough to make contact but I'd worry about reliability. If I ever use up the pile of old igniters I'll have to try those .01" sockets.
Do you know the manufacturer or product spec for the "socket" your using?
Perhaps others would like to try the Circuit board or free floating set up with their old Plug type igniters.
Those Mill-Max Strip pin/sockets I use are purchased in 20 pin strips razor sawed into 10- 2pin segments. the socket end takes the .0100" 30ga. Nichrome or can be soldered in place if additional security is needed. I get mine from Allied Electronics listed as (20pin .100" mill-max socket Strip Cat No. 900-0265) Mfgers No. 310-93-120-41-001000. these socket/pins can be stacked with positive contact as high as needed. I've used as many as 3 in series within the Micro Floating head piston assembly...Photo below.
Do you know the manufacturer or product spec for the "socket" your using?
Perhaps others would like to try the Circuit board or free floating set up with their old Plug type igniters.
Nice! They look very similar to the Mill-Max socket strips I'm using just a bit larger opening? do they stack? that is can you plug one into another with positive contact? If so they will likely work just as well as the Mill-Max socket and a little cheaper I believe the last time I got them they were 1.18 per 20pin strip.
Last edited by Micromeister; 20th June 2012 at 01:51 PM.
Nice! They look very similar to the Mill-Max socket strips I'm using just a bit larger opening? do they stack? that is can you plug one into another with positive contact? If so they will likely work just as well as the Mill-Max socket and a little cheaper I believe the last time I got them they were 1.18 per 20pin strip.
Yes, they will stack.
Either way the price isn't a big deal. The shipping is the bigger cost. I had to order stuff to make it worthwhile.
Either way the price isn't a big deal. The shipping is the bigger cost. I had to order stuff to make it worthwhile.
Big 10-4 on that Bill:
Shipping small electronic parts is sometimes maddening! 3 or 4 bucks for the items and 5+ for shipping.
I generally try to hold Electronic part orders until I have several items as well. Recently when ordering anything from Allied Electronics I'll through a few of these 20pin strips in for good measure. sometimes it helps make a minimum.
Using them with my piston burns up a few more per month then would normally be done. I've also installed them in my Semi-permanent micro igniter fixture. Semi permanent do to the epoxy Filler generally goes away with 20-25 launches leaving the 24ga Nichrome needing only wire brushing between launches....Socket would still be good just dirty as all get out, just a bear to reseat, easier to replace it with the same heavy Nichrome loop.
Speaking of All Electronics on-line they have some Great deals on 18 to 28gauge stranded Copper wire and super small SPST slide switches. Recently made up a Pico P-1 & Adrel Alt-LED Altimeter packs with this stuff each fitting T4 body tubes. They have some very nice stuff at very reasonable prices.
Speaking of All Electronics on-line they have some Great deals on 18 to 28gauge stranded Copper wire and super small SPST slide switches. Recently made up a Pico P-1 & Adrel Alt-LED Altimeter packs with this stuff each fitting T4 body tubes. They have some very nice stuff at very reasonable prices.
I've been getting these from them
to connect batteries to altimeters. I think they're made for RC stuff.
First, why not just make a pyrodex mix that you can pack into the nozzle at the time of the flight or just before to act like the CTI starting pellets in their motors. In this case the motor is an end burner not a bates so the pellet would be at the bottom and then your Q2 or whatever would ignite the stuff in the nozzle which would light the motor.
Second, what about using some cellulose (clear) tape to hold the model down until both engines ignite? You could run the tape (or string) under the engines and that extra bit of delay might give time for the nichrome to work it's magic.
I saw a device made to ignite clusters in a past issue of Sport Rocketry, least I think that was the mag. And the device was a fire box with a series of tubes that fit into the nozzles of the engines then under the tubes in a sealed chamber was black powder charge that was ignited by a standard igniter.
Idea was that when the black powder lights, the fire shoots up through the tubes and ignites the engines above.
They used the device for igniting standard rocket motors, so I don't know if a similar deice could work for micros or not.
The most that I have ever lit in a cluster have been three motors in my Micro Cluster Saucer. The last time was awhile ago, before Quest came out with the MMX Q2 igniters. I used QMX igniters stripped from their plug shells, a clip whip and my 12v system (AeroTech controller and emergency jump start battery). In fact that's what I used every time I launched it, and in every launch all three motors lit. I used the infamous toothpick method to hold in the igniters, and made all of the launches using my first Silo as the pad. It was very trying to get all six microclips hooked on while the lightweight saucer teetered precariously on the three toothpicks, but I got it done. It wasn't all that different from setting up my (full-sized) Cobra for launch, other than involving a bit more cursing.
Most of my recent MMX cluster launching has been with my Diminutive Deuce. I have launched it using both QMX and G2 igniters, and quite frankly, I found that the older QMX igniters (plus toothpicks) were actually easier to use. They also seem to be more rugged; I have very rarely ever broken one. G2 igniters, on the other hand, are rather fragile in comparison. The advantages of the current type include being easier to insert in the nozzle and having long, stiff leads. I have a great deal of difficulty using them with my pad adapter (spent 18mm motor type) but they work fine in my Quest MMX Launch Pad because of the igniter holder. I only launch my Deuce with the pad adapter, though. Setting it up for ignition with two G2 igniters is just about as difficult as setting up my cluster saucer for ignition with a clip whip was. (IOW, a pain.) I do it because I love launching the Deuce, but not as often as I would like due to all of the hassle involved.
I always use a 12 volt system when I want to fire more than one motor, regardless of size. I have never tried to fire any monster clusters, though. For what I have fired it has been enough; I haven't needed any augmentation.
Last edited by MarkII; 8th October 2012 at 03:05 AM.
Mark S. Kulka NAR 86134 L1, ASTRE 471, Adirondack Mtns., NY
Opinions Unfettered by Logic • Advice Unsullied by Erudition • Rocketry Without Pity In the forest no one can hear you order a grande caffè misto. Warning: I brake for invisible squirrels
Have to agree with mark on the seemingly fragile nature of Quest Q2 igniters. They are afterall made with a lighter bridge wire then the old plug types. Still I've become accustom to their use for clustering though I perfer my plain old 30ga. nichrome home bent igniters for everything else.
Having self supporting microclips rather then the need for toothpicks allows the old wadding ball & tape pre-installation for single motor models a boon to quick and easy micro flying as well as pre-installing pyrogen tipped iginters in motors for clustered flights.
Newly tested nitrocellouse lacquer/BP pyrogen dip for my Q2's has proved to be very reilable for getting all motors lit, every time using a 12V system. Be it a converted Quest pistol grip contoller, Old Silo Hockey puck controller or tapping into one of the clubs large range controllers.
I think one on the best things most of us can do for ourselves is to get the Launcher (be it whatever make or configuration) up off the ground to a standing height (30-36" or so) were it's SOOOOOOOOOOOOOOOO much easier and less stressful hooking up multi clips,clip whips or just single motor igniters.
I know I'll NEVER go back to getting on my knees to hook up any model rocket for flight again regardless of size. I'm simply loving the little Digital camera Tripod I picked up at Walmart for under 10 bucks. The one I have is 10 segments that fold up into a 7 inch long package that fits very nicely in the bottom of my range box along with the custom 2" x 4" x 3/4" laminated alum & Clear acrylic "launcher base" I fabricated that threads directly onto the standard 1/4-20" camera attachement screw. Add to this a little rangebox 10amp relay and 7amp/hr 12volt GelCell battery. Since putting this "range equipment" together I've had 100% ignition for micro clusters using these pyrogen tipped igniters up to 10 motors, with most Micro-Cluster flying being with 2 to 6 motors by far.
I think the most interesting Clustered flight was a 6 motor MMX in-line XB-70 Valkyrie 180th PMC..just becuause of the in-line nature of the flight...very nifty smoke trail!
If one doesn't want to spent the time making a launcher base a 3" x 3" x 22ga Stainless blast flat blast deflector and 90cents worth of 1/4-20 x 3/4" Stainless Rod coupling and an 8-32" x 1/2" Nylon thumbscrew make a dandy under five minute launch rod holder/adapter that screws directly onto the camera tripod mounting screw. The little contraption will hold our .049" to 3/16" launch rods making a complete launcher for under 15 bucks totally produced with a electic or cordless hand drill, #29 drill bit, 8-32" tap & handle.
To be honest two motor micro clusters I almost always treat as single motor ignition with the exception of using the pyrogen tipped igniters to ensure both motors ignite quickly. Dipped Q2's have made all the difference with these flights particularly with those heavy PMC aircraft like F-14 & F-15's.
One more observation. Don't know how other feel about the Glass beads on Quests Q2 micro igniters but I find them for the most part to be a hindrance to getting multi motor combinations twisted as close to the midpoint between nozzles as possible. removing the bead helps shorten a bit of the excess wire between igniter & propellant decreasing heating time. We're talking hundrenths of a second here but believe me as quick as our micros move...they DO count.
Generally I take a pair of needle nose plier to the bead, crushing it then checking the lead wire to be sure it's clean for best contact.
Last edited by Micromeister; 9th October 2012 at 04:46 PM.
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