Boom snaped in flight :(

[TVaillancourt]

Well I had 4 flights in a row after putting in a new clutch and I was starting to think this thing just might stay together when after a piro flip I hear this weird grinding sound I land and find this.

[TVaillancourt]

Here are some pics.I managed to fly it around and land

Any idea as to why?Just shear torque from piro flips??

I have just short of 2 gallons through this machine and about 5 mechanical failures.If i didn't love this think so much I'd sell it but I'll throw some more money at it and eventually everything that wants to fail will,but where does it stop

I will add that the clutch bell was really badly out of round from factory.I tried to true it the best I could while waiting for new parts.Of course I want to fly and don't want to wait so I flew it and the tail servo gave up then the clutch went so I'm pretty sure its high frequency vibrations that has done all this damage.I have all new parts so I will rebuild it and double check the run out on the clutch bell for sure this time.

[tauscnc]

Wow never seen that. I assume your boom supports were/are tight?

I saw a Goblin 500 today.... How slick. If they would just come out with a nitro version. I am with you. I now, finally, have 6 flights with no issues. Getting close to the 10 I am hoping for. Gonna look it over tonight too.

[TVaillancourt]

All new parts added.New clutch bearing block,clutch bell,Alum fan,new boom and magnets.Looks like I threw a magnet as well(more vibs).The new clutch bell is much better...not perfect but much better.I don't like how they press the pinion in.I would like to see a screw in type like Align or Raptor.

I too would like to see a nitro 500 Goblin.Someone just converted a Goblin 700 to gas.
http://www.youtube.com/watch?v=cKEHjSyx9pY

[TVaillancourt]

Originally Posted by tasupports57601

Wow never seen that. I assume your boom supports were/are tight?

The boom supports were the only thing holding it all together.I just checked and there is a little play for and aft between the two black support ends.I will pull that and epoxy those on.

[FlyawayClyde]

Hey there TV,
The pinion is screwon. I found out pretty much the same way you figured out that your clutchbell is out of round. I wanted to see if there was a way to fix it. I found no way to do it simply, So I just forked out more cash for a new one. Still not perfect, but it is much better. I did though balance everything in the powertrain.

[TVaillancourt]

Originally Posted by FlyawayClyde

Hey there TV,
The pinion is screwon. I found out pretty much the same way you figured out that your clutchbell is out of round. I wanted to see if there was a way to fix it. I found no way to do it simply, So I just forked out more cash for a new one. Still not perfect, but it is much better. I did though balance everything in the powertrain.

Your comment about how the pinion is screwed on peeked my intrest so I had to run downstairs and take it apart.
Yup it is screw on.It is worse than press in.There are only 4 threads or 5 turns to attach the pinion.Would still like to see more meat for the pinion to be supported by like Align or Raptors have.

[TVaillancourt]

Is it just me or do other people have wobbly clutch bells??
Any one try a bell from another company? I sized up a raptor 30 clutch bell its the right size but too tall and pinion is the wrong size.Wish i could find an aftermarket clutchbell

[tauscnc]

Same wobbly here. Tried 2 of them.

[kiteman78]

This fix has worked on mine. Runs within 0.002" and has stayed that way for many flights.

https://www.helifreak.com/showpost.p...29&postcount=8