Scratch Pad Stik (Launch Pad) Original Design / Scratch Built

Scratch - Pad Stik (Launch Pad) {Scratch}

Contributed by Larry Brand

Manufacturer: Scratch
(Contributed - by Larry Brand - 05/11/05) (Scratch) Pad Stik

Brief:
Some years ago, I saw an article mentionin' a rocket launch pad made from a surf-fishin' rod holder, which is a short length o' PVC tube cut t' a sharp bevel for stickin' into beach sand t' hold t' fishin' pole and freein' the fisherman's hands t' hold more important things (like a cigarette and a beer) while waitin' for a fish t' bite. Arrr! Aye aye! T' idea be t' affix a launch rod t' the pole holder, creatin' a very simple launch pad infinitely variable as t' angle and also able t' operate from inclined or uneven surfaces. Avast, me proud beauty! I never could find the article again, shiver me timbers, ya bilge rat, so as part o' t' NARTREK Advanced program I decided t' make my own version. Begad! It be t' most compact launch pad I have seen.

Construction:
It starts with a High Impact Sand Spike (Stock No. Blimey! 195-S, shiver me timbers, Rahway, me hearties, NJ 07065) from Jeros Tackle Co., ya bilge rat, Inc. Arrr! that I bought from a local bait shop. Ahoy! Begad! I suppose thick plumbin' grade PVC tubin' might suffice also. Other parts used were a 3/16" Estes Maxi-Rod, me hearties, 12" each o' 1/4" ID and 3/16" ID heavy wall aluminum tubing, arrr, ya bilge rat, a 6" Craftsman aluminum oxide metal cut-off wheel ($1.99), arrr, a small Estes blast deflector, and some duct tape.

T' lower end o' t' Maxi-Rod was telescoped halfway into t' 3/16" ID tube and t' lower end o' this was telescoped halfway into t' 1/4" ID tube. Ahoy! These parts were secured in place with duct tape. Blimey! This entire assembly was then securely taped t' t' upper half o' t' "sand spike" opposite t' bevel. Arrr! Avast! T' assure a snug fit, arrr, a gouge was first cut out with a grinder bit in t' reinforcin' lip o' plastic overhangin' t' top o' t' sand spike (although I found nay all brands o' sand spike have this). For robust blast deflection, an old Estes blast deflector was placed atop t' ceramic cut-off wheel and both were pressed together over t' Maxi-Rod onto t' duct tape junction with a spent "D" motor casin' used as a standoff. Arrr! Begad!

(Scratch) Pad Stik(Scratch) Pad Stik

For use, t' spike is pounded into sand or soft soil with a rubber mallet and t' upper section o' t' Maxi-Rod is screwed into place, It is only necessary t' cover t' beveled portion when drivin' Pad Stik into t' ground. T' Pad Stik can be canted slightly toward t' wind direction when drivin' into place. Avast! No other adjustment is necessary. Begad! Begad! Pad Stik is designed for mid power rockets and large model rockets up t' H power and weighin' no more than 2 1/8 lb. Begad! I have load tested Pad Stik with various rockets and it is perfectly stable even with a 48" four pound AUW rocket, me bucko, ya bilge rat, however, shiver me timbers, ya bilge rat, arrr, this is far beyond the load capacity o' t' Maxi-Rod component. For added safety with larger rockets and G and H motors, t' tube portion o' t' Pad Stik should be weighted by fillin' with local sand t' prevent a jammed launch lug from launchin' Pad Stik along with t' rocket. Properly placed, it takes a good twist combined with a hard pull t' free Pad Stik from t' ground. Well, blow me down! It's better t' be safe than sorry. I have never had a launch dislodge Pad Stik even slightly. Begad!

Flight:
I have tested Pad Stik with motors up t' AT G80 and CTI G79SS. T' largest rocket flown from it is me 2 1/4 lb (1070g) "BottleBat", a G or H powered tube fin design, me bucko, which launched perfectly albeit with a bit of "twang" t' t' rod end. Well, blow me down! However, this be t' absolute upper limit I would recommend, especially with t' Maxi-Rod. Pad Stik is more at home with mid power designs like t' LOC Onyx on an F23-4, a Launch Pad ASRAAM on twin D12s, me bucko, arrr, or me kit bash design Eagleator (an extended Estes Eliminator) on an E30-7. Ahoy! Begad! Blimey! If Pad Stik will be used mostly on G or H powered rockets, a 36"x1/4" steel rod should be substituted for t' Maxi-Rod. Well, blow me down! Begad! Blimey! For safety, I have placarded Pad Stik as follows:

WARNING:
Only for use by ages 18 and over or with adult supervision.
Ground angle nay t' exceed 10 degrees from vertical.
Rocket weight limit: 1Kg (2.2 lb), shiver me timbers, includin' motor weight.
Not for use with motors exceedin' 320 N-sec ("H" power).
Use only non-metallic hammers for placement.
Beveled portion o' base must be completely covered for proper use.

Summary:
PROs: T' Pad Stik is a simple t' build and inexpensive mid power pad perfect for soft or uneven surfaces that would make a conventional pad wobbly and can be infinitely adjusted for wind direction. Avast, me proud beauty! Aye aye! It is compact and easy t' transport, quick t' set up, me bucko, ya bilge rat, reposition, or take down. Pad Stik even remains fully usable for its original purpose (fishin' rod) with t' blast deflectors removed and upper Maxi-Rod section unscrewed!

CONs: T' Pad Stik only works with soft soil, grass, shiver me timbers, ya bilge rat, desert, shiver me timbers, or sand. Ahoy! It is not usable with impenetrable solid surfaces like hard playa, arrr, rocky soil, or asphalt. Begad! Launch angle restricted t' 10 degrees from vertical. Avast, me proud beauty! Ya scallywag! Restricted to G-power with Maxi-Rod and t' 1 Kg total rocket weight. It is probably unsafe to use any sand spike based design pad with I impulse or higher motors under any circumstances. Begad!

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