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Micromeister

Micro Craftman/ClusterNut
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Wanted to find a was to get folks do share all those little "thingies" we have laying around in our Range Boxes that help perform the mundane but necessary field tasks that make Launch Days go easier.

I'll start things off with something that I've been using a very long time to eliminate most of the "BAD" igniter misfire irritations. I always check Estes, Quest or whoevers igniters with this small 1.5v Pocket igniter tester.

The original was thrown together from excess stuff I had laying around the model shop. A small plastic project box from RS, spst toggle switch, 1.5v lamp and lamp holder, single AA battery holder, two small pieces of Bronze sheet, a tiny bit of scrap hookup wire and a few screws. After a year or so in use I removed the switch which was found to be unnecessary.
Recently I built a custom size smaller AAA powered fabricated styrene plastic version to reduce the size and weight. This one easily fits in any pocket.
I use these testers constantly. I feel one is almost an essential for clustered motor igniter preperation.

Lets see some of the other Gizmos out there:)

1.5v-d2_Pocket Continuity Tester 3pic_01-83.jpg

1.5v-e1_2 igniter continuity Testers AA & AAA_11-16-09.JPG

View attachment Pocket Continuity Tester(Small) Dwg-c_07-13-09.pdf
 
Some Gizmos are so simple they are almost alway shrugged off as common knowledge.

This particular item was invented to help with the always tedious problem of Threading burn strings through Helicopter bodies and later found to be most helpful with other burnstring and elevator actuator elastic lines on Rocket Gliders and some boost gliders.

I call it a Threading KEY:
Nothing more then a 3" piece of .022ga Brass wire with a very thigh doubled back tiny hook on one end and a finger "pull" ring on the other. Because of the items size and thinness a 1/2" x 6" strip of stripped surveyers tape is attached to the ring to help in locating dropped or blown off the table Threading Keys. Sure takes all the fight out of getting burn strings & elastic thread through body tubes and other parts out in the field.
Hope it is of help.

Helicopter elastic threading key-sm_01-90.jpg
 
Another very Old but very useful little gizmo is the Camera Tripod launch rod adaptor/holder.

These simple 2pic "attachments" turn any standard and more recently digital camera tripods with standard 1/4-20 mounting screws into an almost instant launch rod holding Launcher base. In the mid 80's I used an old style HD video Camera Tripod with one of these 1/4-20 Rod couplings & brass thumb screws to hold my 1/8" and 3/16" stainless steel launch rods. Recently an improved and Cheaper version using a 1/4-20" x 7/8" Stainless Steel Rod coupling and 8-32" x 1/2" Nylon thumb screw works great, will never rust and holds rods as small as .049" to as large as 3/16" fits any standard or digital camera Tripod.

Just about anyone with an electric hand drill, Pair of pliers, #29 drill bit and 8-32 threading tap & handle can throw one of these couplings together in under 5minutes.

Tripod Launch Rod Adaptor-a_St.Stl.25in x.875in RodCoupling_08-11-12.jpg

Tripod Launch Rod Adaptor-b_8-32 Nylon Thb-Screw_08-11-12-.JPG

Launch Rod Tripod Holder-Adaptor-zz01b_6pic pic Pg .jpg
 
I like the look of the mini ignitor testers. It looks like something could be easily fit in an Altoids tin-- those make great little containers. It would certainly be easier than to do that than it was to build a railgun that size, I'll tell ya that! :eyepop:
I may have to make one of those tripod adapter thingies, too. That is, if I ever actually get a tripod...
 
Another Helpful Gizmo is a Launch Rod attached model Standoff. Something to get the model Up a couple inches above the blast deflector to protect against Bernoulli Lock and Singeing the aft end of our models.

Back in the dark ages I used to use Ball point pen Springs. Those that fit easily over 1/8" launch rods with a bend in the spring about 2/3rd of the way up that held the model & spring against the rod for most rockets under 1lb these worked fine. As I got into more and more clustered, larger bodied heavier mid power models these small springs couldn't hold the weight. Wooden cloths pins saved the day LOL!

Awhile back in the process of making new 3/4" dia. Aluminum perimeter stakes for the club I ended up with a few short pieces of aluminum rod left over. It occured to me that regardless of the size of the Launch lugs, Rail buttons or standoffs most models will have some point connected to the launch rod well within 1/2". If I off-set a Hole in a short section of 3/4" diameter rod & added a thumbscrew or two, it should make a Handy-Dandy adjustable launch rod stop.

For most smaller models a two screw stop can handle more then enough weight so 3/4" dia. x 1-1/4" long worked out well to space a pair of 8-32" x 5/8" Nylon Thumb Screws. Why nylon you may ask? Nylon has a much higher friction coefficent then brass, bronze or stainless locking against Steel or Stainless Steel launch rods.

To add to the resting shelf, our pass through 5/16" hole (easily passes 1/4" launch rods) is drilled 3/32" from an outer edge. #29 Holes for tapping are drilled off-center but into the drilled rod hole allowing the thumbscrew plenty of bite into the aluminum while keeping them pretty much centered on the launch rod and out of the exhaust jet. This also allows the stop to be positioned to fit the most convenient amount of model resting shelf needed.

Easy enough for most with a drill press and tap set. Scrap aluminum rod or short pieces can be purchased from any number of local and on-line places. Nylon Thumb screws are a McMaster-Carr purchase, I picked up a 100pk for under 7 bucks including shipping. If anyone needs a plan or further info just drop me an e-mail to [email protected]

LaunchRod Stops-c-sm_4 blank bodies_06-22-07.JPG

LaunchRod Stops-d-sm_center punch holes_06-22-07.JPG

LaunchRod Stops-e-sm_ holes Drilled for tap_06-22-07.JPG

LaunchRod Stops-f-sm_Tapping 8-32 holes_06-22-07.JPG

LaunchRod Stops-h-sm_finished 2 -1.25in & 2 - 2in_06-22-07.jpg
 
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A little more involved Gizom is "the RangeBox Relay":
Flying alone or at large organized Club launches flying Clusters can present ignition challanges. Many years ago I leaned the hardway that having enough power at the right instant makes all the difference in a successful 4 & up motor cluster flight and a Crash.
To that end moving the Power source from the Controller "away" side of the launch system to as close "Under" the launcher as possible is the Numeral Uno positive thing anyone can to for themselves clustering BP motors. The second is Checking and Re-Checking each and every Igniter before, and after they are installed in the BP motors.
My first clustering relay launcher was a HUGE 40amp/contact DPDT Power relay. and it's still working, now installed in my EveryDay Solar-Cap Discharge Launcher. However I'm not always carring my 40lb launcher to club launches. What to do for these occasions where we want to fly 2-6 motor clusters but do not want to lug the Big launcher around.
I decided to look into 10 to 15amp DPDT relays and design a small unit that could be carried in a range box along with a small GelCel battery for At the Pad Power.

When this project first got underway Radio Shack had small package Plug-in DPDT 15amp/contact 12V DC coil relays easily available. Today they have reduce contact amp rating to 10amps which still works out well with the new Lower current Q2g2 Quest igniters. Still keep in mind the Relay/igniter power rule of thumb which is 2amps per igniter is still very helpful in measuring our Battery power requirements for clustering.
Since I want to be able to use this Relay set-up with just about any personal, Group or Club controller the system had to be made with simple post hook-ups for the Controller Coil activation circuit.

Care must be given to the continuity ma rating of any system to ensure it will not activate the usually vary low current relay coil threshold, Some Older style Bulb type controllers need to the bulb to be removed or disabled before the controller can be used. Most newer LED continuity check controllers are not a problem.

Since first designing this little unit in the mid 90's it has happily gained a place in my Range boxes along with a small 7amp/hr Gelcel. It and some of it's later brothers have been used on 2-8 motor BP clusters from MMX to D12 & E9's. Occasionally used by others with AP motor clusters but I don't trust slow igniting AP clustering.

The RangeBox Relay has proven to be exceedingly reliable when used with mentioned igniter testing. It is especially nice for quick & easy 2-4 motor model cluster club launch flying.

Range Box Relay-a_system & magneium-AP igniters_01-31-96.jpg

Range Box Relay-d_Inside the Box_09-16-05.jpg

Range Box Relay-e_3pic system view_09-16-05.jpg

134-J4a-Lp02a_3x,5ACluAlt Hooked Up_05-26-12.jpg

RangeBox Relay_Rev Drawing & Wiring-b_01-31-96 Rev.06-23-10.jpg
 
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Painting turn-table Stands & adaptor Gizmo's:

My Paint booths require I be able to rotate the model while painting without touching it. First I adapted an old Ceramic painting manual turntable. then got an idea while watching a TV dinner rotating in the Microwave. a spring driven microwave turntable adapted to take whatever size model motor mount or interior body dia needed.

For the larger MPR rockets one of the 8" Lazy susan ball bearing hardware pieces from Lowe's with a couple 18" square x 1/2" plywood pieces did the trick.

How to adapt between different model motor mounts and be able to quickly change one for another took just a little longer to work out.
Knowing that 1/2" dowels are a perfect fit for 13mm motor mounts, 18mm spent motor casings fit pretty easily on 1/2" wooden dowels and 18mm spent casings fit very nicely into 24mm spend D-motor casing I had the makings of a very easy and quick change model mounting system.
Cutting various lengths of 1/2" hardwood dowels some with 18mm casings on one end, some with 18mm casings on both ands and some with an 18mm on one end and a glued set of 18mm in 24mm casing on the other. I could mount and paint just about any size model I like up to about 1500g. Even a 60" long 3X upscale Orbital Transport was not big problem USD with an adapted double D casing dowel with some added tape build-up to slide easily inside the BT-80 body.

How do these dowels mount to the various turntables? Each turn table not matter who they are powered. Electric, Spring Driven or manual have a centered 3/16" x 2" x 2" scrap Plastic or 1/4" plywood mounting base with a spent D12 (cleaned out of afterburn debris) Epoxy centered. All the interchangeable adaptors now all the way down to Micromaxx .281" body size and Up to 5" diameter build-ups have an 18mm spent casing on the opposite end that slips easily into the D-12 Base "socket". Once in place the model can easily be rotated during painting, then removed to dry in another area while others can go into the chambers for painting.

In the Small Booth I use one of the spring driven turntables under a 2" x 6" Styrofoam multi-model holder that allows 1 to 8 micro's to be primed and base white color coated at the same time.

Pretty Cheap method for NO hands rotating models while painting. Really all that's purchased are the 1/2" diameter dowels, and a couple Manual Lazy susan hardware from Lowe's or a spring driven Microwave turntable from Bed Bath & Beyond (about 15 bucks), some epoxy, scrap Plywood and/or a few sheet metal screws.
 
Assembly, decal & Hand detail painting Jigs.

These two sized fixtures handle all my model making MMX to MPR. I've assembled and finned models as small as .246" (T2) to as large as BT-80 on the same fixture with the additions of various slip on spent motor casings or Casing with Add-on spanner for some of the larger diameter bodies.

Takes all the work out of trying to hold fins while drying with the Double Glue Joint method. Apply the second activation coating of white or yellow glue. postions where you want the fin. adjust and set upright to set.

These jigs make decaling just about any model a snap. Not need to handle the model while the decals dry. just turn the wheel to expose other parts of the model for additional applications.

They are also great for applying epoxy Fillets, Adding delicate detail parts and Detail brush painting without having to handle or move the model until everything as completely set or dried.

Very easy to build with scrap 1x lumber, 1/2" & 7/32" hardwood dowel, some yellow Wood Glue and a few screws. Holes and extra dowels in the bases add multi model holding potential. Fun little projects in themselves.

MM 383uc07b-Lg_Buck Shot Piping & Port Holes_09-24-11.jpg

474cp05b_Interceptor-E Top Decaled Complete_05-12-10.jpg
 
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Micromeister,

You are the gadget guy. I really like those Standoffs. I am goign to have to try to build one when I finally get bakc to my drill press. It sits in hybernation in my garrage.
 
Thanks Chuck:
Hope you awaken your Drill Press soon...those cold snuggle down weather days are coming fast LOL!!!

After a bit more thought. Most folks could just as easily fabricate the Launch Rod Standoffs from just about any 3/4" or larger materal they have laying around....even hardwood dowel, Hole saw Plywood scrap plugs or what have you. Most will hold a thread if using nylon screws and not over tightening.

Solid materials like Aluminum, Brass, Bronze or even PVC, Styrene or Modified Acrylic plastic rod would hold up a good bit longer then wood but we have to use the materials or Scraps we have at hand.

For those who have never used a threading tap before: When treading wood..particularly Plywood with a standard Metal tap it is important to advance only a few turns, then retract & clean the tap cutting threads, advance a few more turns and repeat until the total depth is achived.

The same procedure is followed in metals with the used of a cutting fluid and/or WD-40 or CRC-56 allowing a few more turns before backing off to clear the tap cutting surfaces and channels. Nothing is more frustrating then attempting to tap through an entire piece all at once only to snap the tap off just before finishing, due to a loaded chip channel.

Hope this info helps.
 
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I know this is an old thread, but I came across this video clip for a round sanding tool. I clipped just the portion for the tool. Different sizes of PVC could be just the thing for sanding the ID of tubes, couplers, and centering rings... I have wrapped sandpaper around a dowel and/or used double sided carpet tape but the sandpaper manages to come loose.
 
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