just had two laugh

[akphill]

The pinion came loose on the hk250gt the other day so I pulled the set screw and applied some thread lock to the pinion and set screw and set it aside for another day well yesterday I pulled it and went to fly it and the motor wouldn't turn over and open inspection I learned that I had locktited the motor ;D
So I take the motor out and clean it and the bearings and get it running again .
S I take it back outside and go to fly it OK it would fly for about a minute and then quit so I figured that I toasted the motor it was eating up the battery really fast ;D
OK so I come back in and take the 2 cell battery and motor out of the heli And I put the scorpion in with a bigger esc 3s battery and all

So I take it back outside and fire it up man what a difference in head speed

Well the hk head was not up to it and the feathering shaft blew apart (WOW) is all I can say about that ;D

well so now we have tail boom feathering shaft main shaft assorted control links knight head bars canopy landing skids and pipes
tail rotor shaft thrust bearings main rotor blades ;D

OK so instead of ordering all these parts which is more than another kit I retired the hk250gt not going to fix it

Instead I pulled the cx250 copterx 250 out of its box and am in the process of building it to take the scorpion motor and the rest of the parts from the 250 gt.
Hope this one works better

[akent]

Phil, you need a tach!
I bought one from HobbyKing.
What I do is sit it on the ground facing up, then fire up the heli. Just before it lifts off, you can see the reading on the tach.
With my bigger helis, I gently clamp it in a small vice that I have so it won't move.

Overrevving these things can cause explosions, as you found out!
Kent

[akphill]

akent you might be right about the tach would be nice to know what my nitros are running at also
the scorpion motor and pinion I am using is the same size and speed for the trex 250 so that shouldn't of been an issue tho but what I think is the feathering shaft in the hk250gt is too soft and the screw just pulled out of the shaft
I dont think that should be an issue with the copterx 250 as the only thing in the copterx is the frames and tail boom and head that is copterx everything else including feathering shaft and main shaft is all align tail drive gear and tail rotor gear box and all are align also and all the bearings have been changed also
I am hoping that it will be all go ahead with this one

[Dave]

Of course ak it could have been one of them rogue iceberg things you know that you may have ran into..... ;D Sorry ak just had too, you understand. And the motor, "I had locktited the motor" man that is just to much your killing me here ak

I don't think he needs a tack akent, somebody needs to take the lock tite bottle away from him

OK I'll stop. Really I am sorry to hear that you lost one.

Dave

[akphill]

LOL wife already took the locktite away ;D

[Doozer]

A Tach is your best friend man. An optical tach is awesome, but you need a buddy. I use a SkyTach. None of them are "exact" but with an opitcal one you remain safe. I'm lucky I just drag a kid to the field when I need some HS Measurements. That may not be a luxury for most (read: speak for yourself Robby).

[akphill]

Yes your right Doozer I do need a tach
My friend tached the raptor 50 at 1650 and the titan at 1750 which for my style of flying is plenty of headspeed also tached the 600 at 2100
But i do need to get one so that I can tach the headspeeds on the 500 and the 450s and the 250 It would be really advantages to know what I need to do to them to make them right
I am in the process of looking for the tach that you look through the window and when it stops the blades that is your rotor rpm it works really well
I could set the governor on the 500 but I still would not no for sure what the actual headspeed is so in conclusion yes I do need one

[Doozer]

This is the best one made:
www.espritmodel.com/index.asp?PageAction=VIEWPROD&ProdID=4740

Another good one:
www.miniatureaircraftusa.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=474&category_id=2&option=com_virtuemart&Itemid=82

This is the one I have:
www.heliproz.com/prodinfo.asp?number=804260

Takes a 9v. Remembers your last HS. But you shouldn't use any of these alone.