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Building Tips and technical articles. => 1/2 A building. => Topic started by: Dane Martin on May 21, 2020, 07:14:42 PM
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I picked up another wasp .049 off Ebay. I was the only bidder, probably because it's missing the back plate. Easy enough to make one.
My question is... there's a little H stamped into the case under wasp. Does that have any significance?
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There was a Holland Wasp and an Atwood Wasp.
The “H” is probably for Holland.
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Bill Atwood and Bob Holland were business partners and when they split up they both manufactured the engine for awhile. Yours is a Bob Holland engine. Bob Holland then brought out the great Hornet 049 and 051 engines. I remember getting the factory tuned 049 engine for a Bday present. It cost $5.00 more to get that engine from the factory. I liked that engine a lot more than the Cox TD 049.
The best of the Atwood series was the Atwood Shrike. It had a glow head ALA Cox technology and was by all accounts better than all of its predecessors
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Wow, thank you guys. I had heard a few things about each gent over the years, but never put it together like that. So I actually have both versions then. This, and one on an ebeneezer biplane.
I've got a real good feeling about this engine. Took a little work to get it unstuck, but now it turns very freely. I've been scrubbing it with a soft bristle tooth brush and rubbing alcohol, followed by a light oil. With my finger over the plug hole, and thumb in place of the back plate, it has a very smart 'pop" to it!
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MECOA list a few parts for the Wasp, but unfortunately many are nil-stock, including the backplate. Gaskets, needle, spray bar etc are current.
I assume the Atwood and Holland versions would be interchangeable.
Rod.
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Dane:
I have a whole box of 1/2 A parts.
If there’s a Wasp backplate available, you can have it.
Bob Z.
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Dane:
I have a whole box of 1/2 A parts.
If there’s a Wasp backplate available, you can have it.
Bob Z.
Great! Thanks Bob. Let me know if you see one
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Well, I was off work today so I decided to make the backplate for this wasp.
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Pics
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Pics
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It didn't turn out as light as light as the original. However, I could probably mill out the rear. But I don't think I have the right mill bit right now.
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Well done Dane, that looks great, but if I could make an observation, it could be really beneficial to retain the larger round flange and drill extra mounting holes in it. That way, the engine could be secured to a firewall with more than just the two backplate screws. I've always thought that mounting an engine to relatively soft wood could easily allow the backplate to work loose and leak, as well as allowing the engine to pivot up & down in flight, although that is just a theory as I've never mounted this type of engine to an actual airframe before.
Rod.
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Well done Dane, that looks great, but if I could make an observation, it could be really beneficial to retain the larger round flange and drill extra mounting holes in it. That way, the engine could be secured to a firewall with more than just the two backplate screws.
Rod.
At that stage, I did contemplate that. I also was interested to see if I can copy the original. The answer was yes and no.... I didn't punch out the remainder of the rear section, due to my tooling. That cost me a gram. But I still think I can. It's just manual work on the mill.
As far as the round flange mount... it would be cool to use some flat head screws so it counter sinks into the flange. Then drill the flange as a Cox bolt pattern. Maybe there's a market for that. Haha
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just found a wasp .049 in my pile of suff ,no needle valve assbly or prop nut. yours for parts if u want it RAD