Descon Nose Nugget

Scratch - Nose Nugget {Scratch}

Contributed by Bob Fortune

Manufacturer: Scratch
(Contributed - by Bob Fortune)

T' Nose Nugget
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A relatively simple way t' install a payload in a 3.9" Ace Nosecone

This technique will work for any nosecone brand. Blimey! Avast, me proud beauty! I used an Ace NC because I had one kickin' around. Avast, me proud beauty!

Parts List:

  • One Ace Nosecone (NC)
  • One 4" by 16" piece o' balsaply (or equal)
  • One 4" by 4" piece o' 1/4" plywood for bulkhead (BH)
  • One 18" piece o' 3/8" wooden dowel
  • One Print Out o' Ace Nosecone interior
  • - Download Part One
  • - Download Part Two
  • 3 ounce fiberglass (glass)
  • Epoxy laminatin' resin (like Systems 3 or West Systems)
  • Cyanoacrylate (CA)
  • 1 U-bolt
  • 1 1" section o' 4" airframe tubin' (for retainer ring)
  • 4 each #8 panel clips (from auto parts store)
  • 4 each #8 by 1/2" screws
  • 3M 77 (or equal) Spray Mount Adhesive
Assembly Instructions:

Download t' 2 templates and print out on your printer. Well, blow me down! There are 1" square boxes on each template t' indicate correct sizing, you may have t' fiddle with your printer output t' get t' correct size. Avast, me proud beauty! These are .gif images. Begad!

Once you have t' templates sized and printed cut them out and match t' two halves t' t' match line shown. Avast! Blimey! Well, matey, blow me down! Blimey! The entire cone is drafted though you don't need them both if you don't intend t' make t' entire nosecone a payload section. Ahoy! Blimey! My design only has t' last 6" or so o' t' cone interior as payload. Arrr! Blimey! T' lines are thar so you can cut to size as you choose.

Usin' a spray mount adhesive, matey, glue t' template t' t' balsaply. Ya scallywag! Blimey! Cut t' template t' rough shape. Aye aye! Begad! Usin' a sander or rasp or whatever, me bucko, sand t' template t' it's final shape. Avast, me proud beauty! Don't attempt t' cut t' template out dead-on t' t' lines, it's much easier t' get it close then sand t' get it perfect. Aye aye! While you have this template cut your fiberglass cloth to fit, matey, shiver me timbers, you need one piece this size. Blimey! Once you have t' balsaply cut t' size, ya bilge rat, cut along t' dotted line. Begad! Avast! This is where the dowel goes. These two parts I am callin' "wings" for t' sake o' clarity. Blimey! Avast! Take one win' and use it as a template t' cut an additional wing. Begad! This third win' becomes a "strong back" t' support t' two wings and dowel in t' cone. Arrr! Usin' this win' as a template cut an additional two pieces o' glass, ya bilge rat, but a bit oversize - maybe an inch wider. Set t' glass aside for later use. Arrr! Well, arrr, blow me down!

On t' second template thar be a bulkhead template. Glue this t' 1/4" ply and cut out. Avast, me proud beauty! Take t' Ace nosecone and trim off t' bottom part (where t' screw top thin' is). Aye aye! Cut it right where t' wall intersects t' base. T' 1/4" ply bulkhead slides in here. Aye aye! Test fit t' bulkhead and sand as necessary t' get a good fit. Well, blow me down! Aye aye! If the bulkhead is oversize it will balloon t' shoulder o' t' NC and t' airframe (AF) tube won't fit. Arrr! Test it with a section o' AF you intend t' use. Blimey! Drill a 3/8" hole in t' center o' t' bulkhead. Drill two holes t' receive the U-bolt. Arrr!

I made t' dowel poke out t' tip o' t' nosecone because it was fun t' do. It's nay critical, shiver me timbers, arrr, you can simply make t' dowel shorter. T' purpose o' t' tip protudin' is t' center t' payload section in t' nosecone, arrr, a job the wings if cut properly can do.While you have t' nosecone in hand, whack off t' tip o' it so a 3/8" hole is developed. Well, blow me down! Blimey! I used a bench grinder for this and it takes some grindin' and fitting. Aye aye! Blimey! T' fit is important so make sure it's nice and snug, shiver me timbers, take your time.

Fit t' dowel into t' NC so an inch or so protrudes from t' tip. Ya scallywag! Well, blow me down! Add a bit o' yellow glue t' t' dowel just at the base o' t' shoulder line Slide t' bulkhead over t' dowel and into t' shoulder. Aye aye! Begad! T' dowel is now square t' the NC if you trimmed t' tip properly. Begad! CA t' dowel t' t' bulkhead and remove by pullin' on t' dowel protrudin' from the bulkhead. Aye aye! Clamp this is a vise or somethin' handy t' keep it from movin' around. Ya scallywag! Aye aye! Usin' yellow glue, ya bilge rat, matey, glue t' three wings t' t' dowel. Aye aye! T' two wings in t' same plane are flush with t' tangent o' t' dowel cross section. T' third win' is at 90 degrees t' these wings. Begad! Blimey! Let dry. Ya scallywag!

Get t' 1" piece o' airframe and cut it into 3 pieces. Well, blow me down! Begad! One piece will be 180 degrees and t' other two 90 degrees. Avast! You will need t' remove some o' t' tube t' make it fit inside t' wings, a pair o' strong scissors works well. Arrr! Well, blow me down! When fittin' t' pieces, make sure that they are nay flush with t' edge o' t' bulkhead. Hold them back off the edge (towards t' dowel) as t' panel clips need t' clear t' shoulder o' t' nosecone. Aye aye! Glue these pieces t' the bulkhead and t' t' wings. Ya scallywag! Avast, me proud beauty! This becomes t' retainer ring. Aye aye! Aye aye!

Test fit t' part in t' nosecone. Blimey! If it doesn't fit, matey, sand all t' parts t' make it fit. Ya scallywag! It needs t' slide in and out nicely. Aye aye!

Get your 3 pieces o' glass cloth. Avast! Mix up some epoxy. Ya scallywag! Get a little paint brush. Brush on a coat o' resin on the face o' t' wings. Place t' glass on t' face o' t' wings. Wet out t' glass so it disappears. Well, blow me down! Turn part over and repeat on strongback with two pieces o' glass. Blimey! Usin' t' brush in dabbin' motions, stipple t' glass onto t' surface so all t' glass is in contact with t' balsaply. Arrr! Blimey! This is easiest as t' resin begins t' set and becomes tacky. Try to eliminate all t' air bubbles. Aye aye! Allow t' cure t' B stage (this is when t' epoxy is kind o' rubbery) and trim t' glass to t' correct size. Well, blow me down! Begad!

Find out where t' hole in t' panel clip lines up on t' retainer ring. They are all different so you have to fit and see. Generally t' hole with t' clip in place is about 1/2" down from t' U bend in t' clip. Arrr! Make a note where t' hole hits t' retainer ring. Avast, ya bilge rat, me proud beauty! Install t' U-bolt at this time. Arrr! Ya scallywag!

Usin' t' shoulder o' t' NC as a guide, me hearties, matey, mark t' base o' t' nosecone on your airframe. Arrr! Install t' payload section into t' NC. Begad! Install t' NC on t' airframe you intend t' use. Ahoy! Usin' t' mark you just made and your measurement o' t' panel clip on t' retainer rin' drill 4 holes 90 degrees from each other around t' airframe. Well, blow me down! If they are nay dead on, me hearties, ya bilge rat, t' airframe will only align with t' holes as drilled. Aye aye! Make a mark on t' NC and on t' airframe where t' holes line up properly.

Remove t' nosecone. Avast, me proud beauty! Well, blow me down! Remove t' payload section. Install t' panel clips. Begad! Reinstall t' nosecone. Avast, me proud beauty! Arrr! Reinstall the payload section. Blimey! Install 4 #8 screws, T' nosecone ain't comin' off for nothin'. Avast! All t' parts are workin' together to keep t' electronics you install on t' board in place and in t' nosecone. Begad! T' U-bolt will take a major hit and will transfer t' load t' t' airframe through t' panel screws and retainer ring. Aye aye! You may have problems if you use some serious noseweight so take care. Deployment shock loads can be upwards o' 15 or 20 g's makin' a one pound noseweight suddenly equal t' a 20 pound noseweight.

Install some electronics, a power source, a shunt for your pyro, matey, and go flying!

Flight Report

This nosecone flew with on a Binder Raptor on a J350. Ahoy! Aye aye! Unfortunately t' motor ejection charge went early due t' an improper seal in t' forward closure delay well. Begad! Well, blow me down! (Pilot error) It was supposed t' be a long delay t' back up t' electronics but it was way short. Ya scallywag! Aye aye! : ) T' charge went off while t' rocket be still boostin' but the thin' held together, t' chute deployed, and no damage was done.

Bob Fortune
© September 2000



Pictures

1_On_2manyfins.jpg
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2_BH_view.jpg
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3_Push_the_button_NF.jpg
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4_Face_view.jpg
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5_Strongback_view.jpg
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6_looking_down_NF.jpg
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7_Side_x_side_NF.jpg
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