mwick

Don:

We are flying a Focus II with a ys140 sport and hyde mount. Hatori pipe and flex header combo. Pipe is flex mounted at the rear of the pipe only, no additional support on header. We are breaking too many headers and wonder what solution you have used on the Focus?

Thanks
Mike Wickizer

fancman

My Feedback: (16)

One recomendation I have gotten from Karl Mueller who makes custom headers is to make the header as short as possible by using an additional aluminum piece which in effect has you using two hose couplers and thereby shortening and eliminating stress on the header bolted to the engine.

http://www.rcaerobats.net/Mueller/Exc_Header3.jpg

Don Szczur

My Feedback: (1)

Focus II. Take a hack saw and carve out 3/4 inch on either side of the front of the pipe tunnel bulkhead. Then slit the belly-pan 3 inches front-to-back on either side mid- way around the curve, to give relief. I broke 6 headers til I did this. Since then I've been running the same one....


Don

Pattern freak

My Feedback: (1)

Hi mwick,

If i`am not mistaken Don uses the NMP header.You are using the Hatori flex header#HAT796.

I`am using a ES carbon fiber pipe with the Hatori#796 flex header.I have my pipe and header mounted with the Dave Brown hush clamp.
One at the end of the pipe and the other at the end of the header,were the pipe meets the header.I have 104 flights on my FOCUS 2 with the same header and it`s still going strong.

You have to have a header mount on your header,specially the flex headers otherwise the headers won`t last 10 flights each,believe me i broke about 4 Hatori flex headers in 1 month.In my other planes.

I modified the hush clamp so that i could use an aluminum hose clamp to tighten the header to the mount,it`s not the lightest way around but it works perfectly and to catch the pipe i use high temperature hose.With two clamps one for the pipe and one to tighten the header to the hush clamp.
You`ll have to make an additional wooden brace with a blind nut to rest the hush clamp where the pipe meets the header.Just the same like you did for the Pipe.

I hope this helps.
Greg.
www.arubarcclub.com

mwick

Thanks all for the recommendations. This forum sure is a wealth of knowledge.

Mike Wickizer

mwick

I realize I have another question....On the header brace do you mount the brace to the engine, mount, or some other place? Seems if you mount header brace to fuse or motor box the vibration problem would be increased?

With everybody's help maybe I can keep my son's plane in working condition.

thanks
Mike Wickizer

Pattern freak

My Feedback: (1)

Hi Mike,

Are you using the Hatori flex header #796???.

I have mine in the fuselage.Where the header meets the pipe.I don`t think the vibration will increase,i use a hush clamp from Dave Brown the 60 size,there are 2 sizes a 40 and a 60.
The hush clamp has rubber isolation thus reducing the vibration,if you hard mount the header you could break the haeder because you are using a soft mount on your engine.And i think you could get a little more vibration too not so much!!!! because of the hard mount.

I have my header brace placed right underneath the END of the header,actually in the fuselage,you have to cut a hole in the fiber glass pipe tunnel so that you could screw the hush clamp in.

I have a lite ply brace and a blind nut so that i can screw the hush clamp in.

Greg.
www.arubarcclub.com

mwick

thanks for the help

Mike