Question from new member

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Question from new member

Postby Harvey » Wed Nov 24, 2010 8:12 pm

Hi,

After 40+ years in R/C, I'm just now getting involved in spark ignition engines. For years they have been a distant interest of mine but now with the availability of new reproductions and auction sales of originals, along with 2.4GHz radios, the ability to find and operate them is improving. So much so that I recently picked up an O&R 60, an O&R 23, and a Cameron 23 and I'm looking forward to putting them to work.

However, one thing that stands in the way of practicality is the lack of a throttle control. A mention in the Dec 2010 Model Aviation (pg 149) talks of someone successfully adapting a Webra .60 R/C carburetor to a Forster 99.

Anybody else have any success with throttling an old sparker? I'd like hear your thoughts on this.

Thanks,

Harvey
Last edited by Harvey on Thu Nov 25, 2010 4:44 pm, edited 2 times in total.
Harvey
 
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Postby chiefss » Thu Nov 25, 2010 1:58 pm

I converted an Ohlsson 60 to R/C using and OS 4BK carb. I cut back the intake tube and machined an adapter for the carb. It ran fantastically. Idled at 700 rpm with the spark retarded. I had to use a PCM radio as the open points created interference. The PCM noticed it but didn't glitch so it worked well. It was on a SIG Kadett Senior. Ran a 14x5 prop. Used glow fuel 3 to 1 castor NO nitro.

My dad did the same thing with a Forster 99 years ago. The plane was Tail heavy and hit the ground on the first flight. Not much damage but the engine was worth too much to use that way so he went to an OS 60 four cycle.

Send me your email address and I'll send you a picture
chiefss
 
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