Scratch Lump-O-Lead Original Design / Scratch Built

Scratch - Lump-O-Lead {Scratch}

Contributed by Matt Gillard

Manufacturer: Scratch
(Contributed - by Matt Gillard - 12/14/07) LOL

Brief:
I be full o' good ideas for t' glider that I was goin' t' make. Well, blow me down! None o' these came t' be and instead I made a pop pod glider. I foolishly went for a large (ish) glider as I did nay want t' simply replicate a glider that I already had. Avast, me proud beauty! T' result be a glider that needs at least a D t' lift it, matey, but will also shred on a D.

Construction:

T' glider itself consists o' a four panel win' with a three panel tail. Blimey! Blimey! Ya scallywag! Blimey! Two 1mm by 1mm spruces act as side by side booms, with a front fuselage made out o' 3/8th inch balsa. Well, blow me down! Blimey! T' pop pod be t' pod from a Quest Flat Cat.

Win' Construction:

2 panels. Well, blow me down! Begad! 3.5 by 6 inch

2 panels, arrr, shiver me timbers, me hearties, 6 inch long with ends measurin' 2 inch and 3.5 inch

T' centre panels were glued together with one win' tip 1 inch o' t' bench.

When t' glue had dried, t' outer win' panels were added, again with a one inch lift.

Side Tail:

Two panels o' balsa measured 5 inch with t' sides bein' 2 and 2.5 inch, were glued together. Blimey! T' angle formed matched t' front wing.

A rudder be attached underneath, this panel measured 4 by 2 inch, ya bilge rat, and was trimmed down somewhat.

Booms:

These were made from 1mm by 1mm spruce (which turned out t' be a big mistake) both rods were 17 inches long. Ya scallywag!

T' booms were glued t' t' outside edges o' t' tail, me bucko, and them t' front win' was glued t' t' front.

Front Fuselage:

A 15 inch piece o' 3/8th square balsa formed t' fuselage. Well, ya bilge rat, blow me down! A 3 inches piece was glued t' t' top end o' the fuselage. Blimey! When this dried, a front cavity was made t' hold balancin' mass, me hearties, and t' hook/catch mechanism was cut out. Two thin pieces o' balsa were then glued t' t' out side edges o' t' front fuselage t' complete t' cavity box and edge off t' catch. This whole front end was very similar t' front end o' a Quest Flat Cat t' fuselage be then glued to t' front wing.

Pop Pod:

This was a steal from t' Quest Flat Cat.

Finishing:

T' whole glider was sanded down, shiver me timbers, all edges were rounded and a slight aerofoil added t' t' liftin' surfaces. Begad! Well, blow me down! The rocket was then sealed.

T' design was that as t' aft booms were out o' t' way o' t' motor thrust, thar was no need t' protect the fuselage. I knew t' glider would be tail heavy so t' cavity at t' front would take mass t' balance. Begad!

Wing Test Glides:

Several test glides were needed t' get t' glide right, ya bilge rat, in t' end a big lump o' lead be needed t' balance the glider –this is where t' glider's name comes from.

Flights:

First flight be on a B4-2

Lift be straight but nay t' high, ya bilge rat, me bucko, t' lump o' lead at t' front came out and she fell tail down –my fault. Avast, me proud beauty! Begad!

Second flight was on t' came motor with a lump o' clay actin' as t' mass at t' front. Arrr! Again t' lift was straight, but t' pop pod did nay pop! T' whole thin' came in nose first, matey, thar was a lot o' balsa t' glue back together.

Third flight be a few days later, and after repairs. This time a C6-3 was used, me hearties, me bucko, t' higher thrust made t' whole thin' shake on lift, me bucko, arrr, so much so that t' tail shredded. Well, blow me down! T' glider, shiver me timbers, me hearties, now heavy, nosed in again – more gluing.

Damage Fourth flight. Begad! Blimey! Begad! Blimey! Again a C6-3 be used, t' flight was straight again with less wobble, ejection was clean and t' glider glided in on a steep angle. Avast! Blimey! There was damage.

Summary:

T' glider is too heavy for an 18mm motor and a D would rip it apart. Avast! I should learn t' walk before I can run, matey, I have had me own design smaller gliders perform very well, and I've had large kit gliders work, me hearties, but I'm nay quite ready for t' large birds yet.

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