Tuned Pipe mount
10-19-2013 | 06:12 PM
#1
Thread Starter
My Feedback: (6)
Tuned Pipe mount
I need some suggestions on how to clamp a 1 3/16" dia tuned pipe exhaust. It will lay flush with the side of the fuse.
Is a hose clamp bolted to the side of the fuse sufficient?
This is on an old MK Mini Curare kit. It is all set to go just need to hold down the pipe.
The mini was built 15+ years ago and acquired through an estate sale. It never had a radio installed came with a OS 25 so it was replaced with my hot K&B .21 FIRE on a 1/4 wave pipe. Mechanical retracts it weighs ready....... ready ...
3 pounds 6.5 OZ ready to fly. This is such a cute plane and should fly really fast! I am stunned by its light weight.
Sparky
Is a hose clamp bolted to the side of the fuse sufficient?
This is on an old MK Mini Curare kit. It is all set to go just need to hold down the pipe.
The mini was built 15+ years ago and acquired through an estate sale. It never had a radio installed came with a OS 25 so it was replaced with my hot K&B .21 FIRE on a 1/4 wave pipe. Mechanical retracts it weighs ready....... ready ...
3 pounds 6.5 OZ ready to fly. This is such a cute plane and should fly really fast! I am stunned by its light weight.
Sparky
10-19-2013 | 09:24 PM
#2
Joined: Feb 2007
Posts: 939
Likes: 0
Received 0 Likes
on
0 Posts
From: Norco, CA
Here's 3 from Tower Hobbies
http://www3.towerhobbies.com/cgi-bin...?&I=LXB857&P=0
http://www3.towerhobbies.com/cgi-bin...?&I=LXB864&P=0
http://www3.towerhobbies.com/cgi-bin...?&I=LXZ667&P=0
I would suggest mounting at least an 1/8in plate on the inside of the fuse so the screw has something to bite into. I epoxy a 1 x 1 in plate an the side of the fuse then cut a square hole in the balsa fuse side with the same thickness of ply so the mount doesn't squish in the fuse side.
http://www3.towerhobbies.com/cgi-bin...?&I=LXB857&P=0
http://www3.towerhobbies.com/cgi-bin...?&I=LXB864&P=0
http://www3.towerhobbies.com/cgi-bin...?&I=LXZ667&P=0
I would suggest mounting at least an 1/8in plate on the inside of the fuse so the screw has something to bite into. I epoxy a 1 x 1 in plate an the side of the fuse then cut a square hole in the balsa fuse side with the same thickness of ply so the mount doesn't squish in the fuse side.
10-20-2013 | 08:57 AM
#3
My Feedback: (3)
Sparky,
those MK 20's are wonderful little classics!
3.5 lbs is right in line with spec weight - a little lighter on a smaller light engine like the K&B 21. Folks have put up to 32 and 35's in these MK 20's but mainly in the larger ones like the Aurora and Cosmos. Another excellent RE engine choice would be the NovaRossi R528 - a 28 size engine with outstanding performance.
For the pipe, just bolt a small cradle base (like that in the DB units or made from dowel and 1/32" ply) and hold the pipe to it with a good tie wrap. Keep it toward the rear of the pipe where the temps are lower. You can use heat resistant tape between the pipe and cradle. Avoid metal to metal contact.
Post some pictures!
David
those MK 20's are wonderful little classics!
3.5 lbs is right in line with spec weight - a little lighter on a smaller light engine like the K&B 21. Folks have put up to 32 and 35's in these MK 20's but mainly in the larger ones like the Aurora and Cosmos. Another excellent RE engine choice would be the NovaRossi R528 - a 28 size engine with outstanding performance.
For the pipe, just bolt a small cradle base (like that in the DB units or made from dowel and 1/32" ply) and hold the pipe to it with a good tie wrap. Keep it toward the rear of the pipe where the temps are lower. You can use heat resistant tape between the pipe and cradle. Avoid metal to metal contact.
Post some pictures!
David
10-21-2013 | 07:10 AM
#4
Thread Starter
My Feedback: (6)
Dave,
Thanks for the suggestion, the little K&B .21 were the last of the .21 run and were built specifically (timed) for R/C Combat they are considerably higher performance that the "normal" .21 however this is the first one I have tried with a 1/4 pipe. I am sure it will respond some what to the pipe. I also have 5 or 6 of these little powerhouses (2 NIB) from when I was flying SCALE R/C combat (2000 class 2105 national points champion) the carb throat is about the dia of most .40's. I hope to fly before the weather chases me inside here in the Midwest. I was in Toronto last Thursday night really lousy weather but at least it was above freezing.
Sparky
Thanks for the suggestion, the little K&B .21 were the last of the .21 run and were built specifically (timed) for R/C Combat they are considerably higher performance that the "normal" .21 however this is the first one I have tried with a 1/4 pipe. I am sure it will respond some what to the pipe. I also have 5 or 6 of these little powerhouses (2 NIB) from when I was flying SCALE R/C combat (2000 class 2105 national points champion) the carb throat is about the dia of most .40's. I hope to fly before the weather chases me inside here in the Midwest. I was in Toronto last Thursday night really lousy weather but at least it was above freezing.
Sparky
