(more) crayon help

[rabidsheeep]

well, my mom somehow has this knack of finding things, (like somones rocket that landed in a creek somewhere, which was just massivly ironic)... when she picked me up from school she shows me CRAYONS!

finally i got my hands on some that she somehow found in the trash LOL

Theres two, one seems like a normal size, the others almost 6 inch diameter

the 6 inch one is too heavy for me to fly it on anything i can get my hands on, but the normal one might be nice...

it has a plastic top, which is almost already in nosecone form (pops off, just needs sanding) and a plastic tail end

now, i kinda wanna leave the tail end on becuase its a good 3 inches worth of the rocket, so if i extend the mmt (say 29mm) past the plastic, of which i will drill a hole in, will the blast be far enough away to not melt the plastic?

also, is there a trick to simming these?

im thinking an off scale AIM54Crayon pheonix style to go along with the family

thanks

--sheeepy

 

[rbeckey]

Here is a decent sim. The plastic won't melt. The hardest part is getting something to adhere to it.

 

[lalligood]

Originally posted by rbeckey
The hardest part is getting something to adhere to it.

Gorilla Glue (or any other polyurethane glue) works amazingly well for adhering to the mysterious plastic those crayons are made of...

HTH,

 

[rbeckey]

I used polyurethane glue for the NC bulkhead, but went with through the wall fins. I made the tail cone removable from the end of the tube, so a couple small screws were used there. I also roughened the inside of the NC in the areas were I expected glue to stick, at the point for the nose weight and around the base for the bulkhead.

 

[Bowhunter]

If its plactic rough it up then if you think its ok go over it agian. the rougher the surface the better your glue or epoxy will hold. just my 2 cents

 

[Bowhunter]

heres the Crayon family

 

[BlueNinja]

Will, say, LOC CR's fit into the crayon tube? or is it a really non-standard size?

 

[lalligood]

Originally posted by Blue_Ninja_150
Will, say, LOC CR's fit into the crayon tube? or is it a really non-standard size?

Crayons really are non-standard size. IIRC, it's 3.75" ID...

 

[Micromeister]

I agree with Bowhunters all my crayons are fabricated with 5 and 30 minute epoxy. Clear lexan fins are attached to the plastic pieces and cardboard tube by drilling 1/16" holes in a random pattern about 1/4" on either side of the fin joint and the root edge of the fin to form epoxy rivits. My 4" crayon is a 5 D12 motor cluster. the bottom of the plastic cap is used for the bottom centering ring with a 3/32" thick light ply forward ring the reduces inside to the BT-60 stuffer tube to the chute compartment about 12" below for forwar edge of the crayon forward end. All the ring are hand cut with circle "compass type" cutters usually used for cutting photo matts. takes a little time but always gives a nice tight tube/ring fit.