Bob's Gilbert "Skyflash" Bob's Extra .11 Runs on a Test Stand

Yes, that right side exhaust stack's engine threads were hogged out when I got it.  I thought just a small dot of JB Weld on the threads would be enough to hold it yet allow it to be backed off and removed later if necessary.  Blue locktite would work too but would not be as reliable.

Or, just swap out engines. Two 2/56's up through the bottom and your there.

Perfect timing too , for the event that sounds like alot of FUN . Man i wish i were closer there don't seem to bee much happening around here with flyins any more I use to really enjoy going and could get to fly somebody elses easy fly plane .. The Good ole days .

getback wrote:Perfect timing too , for the event that sounds like alot of FUN . Man i wish i were closer there don't seem to bee much happening around here with flyins any more I use to really enjoy going and could get to fly somebody elses easy fly plane .. The Good ole days .

Perfect timing too , for the event that sounds like alot of FUN . Man i wish i were closer there

You and me too pardner, you and me too!!!!

Yep..."Glory Days"

Kim wrote:I put Bob's extra .11 on a stand, and used a MA 7x4 prop I had handy.  Like its sibling, it took me a while to get the balance right with the needle setting, but it actually ran quite steady once I got there. I think the 7x4 is a bit much for it though, with it mostly hovering around 8K, and may pull the 6x4 from his Skyflash if I do another run. Weird & Wonderful Little Castor Slingers!

Kim, you may want to read:

Sceptre Flight Model Engine Tests  Gilbert 7 & 11

From Dec. 1994 Model Engine World:

Model Engine World wrote:Normally, sideport engines run out of breath above 10,000 rpm, but not this one, the Gilbert .11 is an engine that really likes to roar!! I would imagine the bhp curve to be very steep.

RPM Figures
Fuel 10% castor, 10% ML70, 15% Nitro Methane, 65% methanol

7x5	Graupner	9,100
7x4	APC	13,700
7x3	APC	15,000

Seems that APC props allow higher revving versus the Master's props. Additional note:

I think we can also draw additional feel for the Gilbert .11 from the similar designed side port 1959 Fox .09 Rocket (0.099 in displacement):

Sceptreflight: Fox Rocket 09 May 1960 Model Aircraft

placed the engine at 0.11 BHP at 14,000 RPM. The .11 Gilbert may be a touch above, as it is .010 Tee Dee in size above the Rocket. However, those articles give some decent clues, too. Fox Rocket did excellently on a 6x4 prop. It's HP curve:



The Gilbert IMO compares favorably to the weaker .09 - .10 engines of the times, the 1950 Duromatic McCoy "9", 1950 OK Cub .099, 1954 OS .099 twin exhaust port, 1961 Frog .09 Venom, 1967 Fuji .099S, 1969 Ueda .09 RC, etc. Some unfairly compare it to the other more power engines, but it has it's place as it does have more power than the .049 Reedies. In fact, interestingly enough, it has more power than some of these weaker legacy engines.

In contrast, the 1965 Enya .09-III TV put out 0.16 BHP at 14,500 on 5% nitro according to Peter Chinn. The venturi CL / FF version put out 0.19 BHP at 16,000 RPM, all on 5% nitro.

Where the Gilbert stands, it is a very mild ".09", probably not too far off from the Fox Rocket.

Kim wrote:Thank You! Gonna check my main inventory of props once my van gets out of the shop (they're all locked in it). Further testing will happen!

Kim, you're welcome, looking forward to your findings.