Back Plate Difference

The backplate on the left is pre-1960 vented for non-stunt tanks (unless the tubes are undrilled), middle backplate is a post-1960 stunt-tank backplate with an aftermarket (Kustom Kraftsmanship?) fine thread NVA, and the one on the right is a post-1960 vented backplate for non-stunt tanks.

While there are others more knowledgable than I, I will give it my best start at it.
Top row, left to right.
1. Second generation Bee type backplate with 2 filler tubes (First generation I beleive were just metal color, and not the gold type. Second generation had the coating. 1st and 2nd did not have manufacturing marks) No screen on these I believe.
2. Third generation Black Widow/Golden Bee backplate with aftermarked needle valve assembly (cannot remember the manufacturer that did the mods and sold them) Also, stamped Made in USA. Also note that the screen is removed.
3. Same as the first, only a bit newer, stamped Made in USA, and still has screen installed.

The only other differences would be the air intake /venturi on the backplates may be of different diameter per the different engines. Hope this starts to clear up the confusion. Also, I am sure others will chime in here and correct me if I am wrong. Thanks.

All three are desirable IMHO.. Now only available "new" in plastic. The plastic ones will break in a crash before the metal ones will. The 4 lugs for mounting radially to a model airplane firewall will receive a large degree of "shock" in a nose-in crash.

Maybe I should give the plastic type more credit?? Could be that their failing in a crash, might prevent more severe damage to the nose of the crankcase.. when compared to a metal backplate being mounted to a substantial ply/hardwood firewall.

You can also drill a hole through the tank-wall and run the fuel-tubing out to an external fuel tank/source.. and forgo the numerous gremlins associated with getting the integral tank to seal properly. When used as a carb "only".. the stock (Bee) backplate/carb draws fuel quite reliably from an external tank.

The below pic shows one of my Cox Babe Bee 5cc tank-bowls drilled-thru to receive a rubber grommet for Dubro sm. size. silicone glow-fuel line to pass-thru. The muffler/baffle is homemade.



Those metal backplates should be saved.. even if all other parts were junk.

UNC 2-56 nylon screws can be a problem solver for broken lugs. I didn't give a try yet.

http://www.modelfixings.co.uk/nylon_screws.htm#unc%20hex%20head

Hmmm. Now that is a very good thought and idea. I think that they would definately be worth a try. Even if you broke one here and there. They are used in .40 size planes to hold wings on, although bigger, but there is a good amount of stress on them and I have not heard of many people complaining about them on those.