Foil lined tubes

[ga1ba2]

My BMS clone of the month came with a foil lined motor tube. It also has an engine hook. Any special glue needed to attatch the thrust ring? Does the area need to be scratched so the glue sticks?

[stefanj]

I've always assumed the lining needed scratching. I marked off the handle of my skinny X-Acto and scraped away the area.

I used yellow glue.

[Bob Thomas]

I used some foaming gorilla glue forward of the thrust ring as a backup - it sticks to everything, use very little.

[ga1ba2]

Thanks for the info. The tube is 9 inches and the rocket BT is 34 inches and I installed a baffle in the top about 8 inches from the NC. Do I really need all 9 inches of the motor mount or can I just cut it off a little longer the what I need for the engine and thrust ring. I intend on using a E engine or a D with a spacer

[Bob Thomas]

The only reason I would think the foil tube is extended is to protect the main body tube just a little longer from the hot ejection gases and particles. Naturally, the longer tube also "aims" the ejection charge further up the tube (have you ever experienced a sidewall burn through just in front of the ejection charge? It is awful!)

If CG isnt a problem, the weight of the extra foil tube might only matter in competition.