Wanted Glow Head #302 Space Bug

Thanks Joe

jsesere wrote:I have some. PM sent.

Do you have one for me?

The posted picture says a lot, but I would like to see more technical specs on the old plug design. Would this be considered a hi, med, or low compression plug by today's standards? What is the thread diameter and pitch? Other than changing the thread design to match the bottom cylinder thread for reduced tooling costs, does anyone know why the design change was made?

I don't know the technical details of the early small diameter heads, but I do know that the OK Cub .049 (A/B) heads which take a plug will screw in, although I've never tried it and don't know how the set up might peform. As you probably know, the later Cubs used a glow head the same thread as the common Cox which sealed at the bottom. The earlier Cub heads sealed at the top like the early Cox. If you wanted to operate an early Cox engine & were'nt worried about authenticity, then the Cub head option may be viable to yet the engine flying.

Rod.

Perusing eBay, I have learned from Dan Sitter (California Dan) that he sells the same identical glow plugs that fit all modern Cox engines plus the later OK Cubs using the Cox style head. So I deduced that kind of interchangeability did exist. But you have opened up the thought that it works the other way around, too, in that an old Cub head would fit the small thread Cox. What brought up the situation is this. I saw a NIB Cox Space Bug on eBay a month ago, and the seller was knowledgeable enough to realize and state new Cox plugs would not fit, but rather took the older smaller plug. (A good collector item but my intent is to buy and fly.) So I hesitated to buy not knowing if I could get a replacement plug that would work after the original burned out. But this possible interchangeable head thing with the Cub head throws this issue into a whole new light as I am not into authenticity. I appreciate your insight and comments. Tom