IMAC Double Build, Carden Pro 124" Extra 300 40%
- Thread starter orthobird
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- 40% airplane build thread imac
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That Extra looks AWESOME @orthobird. I really like the "Old School" trim scheme. . . . . 
Started to work on the Baffle for the airplane with the twin cylinder. I really like this baffle or cowl air intake duct.
I got it from the online Carden Store, it is fiberglass, and weighs close to nothing.
1st thing, I positioned it into place, and then applied a layer of fiberglass tape with resin, to help hold it to the bottom cowl segment.
Once this cures, I will remove, and do a better job of fixing it to the bottom cowl piece. Then, trim it, and finally, can primer and paint it.
I got it from the online Carden Store, it is fiberglass, and weighs close to nothing.
1st thing, I positioned it into place, and then applied a layer of fiberglass tape with resin, to help hold it to the bottom cowl segment.
Once this cures, I will remove, and do a better job of fixing it to the bottom cowl piece. Then, trim it, and finally, can primer and paint it.
Rusty 73
100cc
Cam don't take this personaly but if you don't remove the bottom 1/2 inch lip on the cowl you will create turbulence of the air before it reaches the cylinder heads and reducing the full smooth air flow towards the heads ,
I noticed that on Carden webpage with the spare parts that they did leave the fibreglass web up the spinner which would create a negative pressure point and the air will swirl behind the spinner and not over the engine .
Just something i noticed and take it for what it's worth , I do like the fibreglass baffle i wish all reputable Manufactures of Arf's would include it in their kit.
Proper airflow management is very important when you start putting high demands of performance from these two stroke engines .
I would even open the bottom air inlet on the cowl and get a Secraft air intake manifold to help breath cooler air rather than the 300 degree air coming down from the heads from the heads . Colder air produces better horsepower and performance.
I noticed that on Carden webpage with the spare parts that they did leave the fibreglass web up the spinner which would create a negative pressure point and the air will swirl behind the spinner and not over the engine .
Just something i noticed and take it for what it's worth , I do like the fibreglass baffle i wish all reputable Manufactures of Arf's would include it in their kit.
Proper airflow management is very important when you start putting high demands of performance from these two stroke engines .
I would even open the bottom air inlet on the cowl and get a Secraft air intake manifold to help breath cooler air rather than the 300 degree air coming down from the heads from the heads . Colder air produces better horsepower and performance.
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Rusty 73
100cc
This picture is from secraft site this guy even went as far to baffle the heads to control the air flow and the velocity stack is in reverse drawing warmer air from the headers . Iwould rather have it facing forward to get clean air . Again this is just my opinion and other flyers have a different view
Hey Rusty, you will not believe this, but I was just in the shop doing just that!! LOL!!
Geniuses think alike!
In fact, the bottom lip was only kept on there to allow me to stabilize the air duct with a piece of tape. once this cured, I went back in there, removed the cowl, and have placed tape and resin on the bottom of the air duct, to the bottom cowl piece, then, I removed the upper lip with my dremel!!
LOL!!
Man, we are two of a kind.
Yes, that picture you have posted, with that velocity stack, I will disagree with as well, the warmer air is not better! (unless you are flying year round in very cold weather)
Ideally, best case scenario would be to get a velocity stack that sticks out the bottom of the cowl, so the air does not come in from the inside of the cowl. This would be ideal, except, then you have to worry about bugs and debris getting in there, so that is why I go the route of leaving it stock.
otherwise, that picture you have posted is amazing baffle set up around the cylinder heads! I like that, Hopefully, it is open in the bottom!
Geniuses think alike!
In fact, the bottom lip was only kept on there to allow me to stabilize the air duct with a piece of tape. once this cured, I went back in there, removed the cowl, and have placed tape and resin on the bottom of the air duct, to the bottom cowl piece, then, I removed the upper lip with my dremel!!
LOL!!
Man, we are two of a kind.
Yes, that picture you have posted, with that velocity stack, I will disagree with as well, the warmer air is not better! (unless you are flying year round in very cold weather)
Ideally, best case scenario would be to get a velocity stack that sticks out the bottom of the cowl, so the air does not come in from the inside of the cowl. This would be ideal, except, then you have to worry about bugs and debris getting in there, so that is why I go the route of leaving it stock.
otherwise, that picture you have posted is amazing baffle set up around the cylinder heads! I like that, Hopefully, it is open in the bottom!
Rusty 73
100cc
LOL.. Geniuses well i guess maybe.
That has come from many years of racing with an engine under a cowl and going very fast, we had to figure out a good way to vent the heat while keeping the performance stable .
Im glad i didn't offend you about the lip on the cowl i should have guessed you had that covered .
Getting back to the velocity stack, i guess maybe i guy could lay up a tube from the inlet port so it directs the cool air about an inch or so in front of carb thus
giving an debri a chance to fall down into the cowl and not into the carb .
That baffle setup is well done , looks like stainless or 6061 sheet bent to 90 degrees and fastened to the cylinder base bolt and attached to the carbon fibre baffle.
Looks likes a former air dynamics engineer from Formula racing had nothing to do but than create this piece of art .
Today we went to the mountains for a dip in the hot springs (39c -102f) and went out to the Grizzly paw restrauant for supper , family time
That has come from many years of racing with an engine under a cowl and going very fast, we had to figure out a good way to vent the heat while keeping the performance stable .
Im glad i didn't offend you about the lip on the cowl i should have guessed you had that covered .
Getting back to the velocity stack, i guess maybe i guy could lay up a tube from the inlet port so it directs the cool air about an inch or so in front of carb thus
giving an debri a chance to fall down into the cowl and not into the carb .
That baffle setup is well done , looks like stainless or 6061 sheet bent to 90 degrees and fastened to the cylinder base bolt and attached to the carbon fibre baffle.
Looks likes a former air dynamics engineer from Formula racing had nothing to do but than create this piece of art .
Today we went to the mountains for a dip in the hot springs (39c -102f) and went out to the Grizzly paw restrauant for supper , family time
Hey Rusty, you will never meet someone else like me. I spent 4 years in medical school then 5 years in Orthopedic Residency training, And I was forced and accustomed to taking criticism and being told things. IF one is unable to take advice or recommendations from others, then we are hosed. I always say, you are only as good as the people around you. SO that is my motto. In fact, when I do surgery, I always tell everyone, "I need your help". I have no ego! We all work as a team! And, I always listen to others, as I know, they mean well, as you have. You only want to help, and I am all for it. The more brains, the better! So go away, and tell me what ever you want, except, no mom jokes or anything like that!!
WOW< so there are hot springs up there, that must be so relaxing! Enjoy family and wish you a happy New Year!
WOW< so there are hot springs up there, that must be so relaxing! Enjoy family and wish you a happy New Year!