250 I get it now

[pvolcko]

In the process of repairing the 300X. I get why people don't like these size heli's now. They are a pain to work on.

Anti-rotation bracket: sandwiched between the two frame halves, so you end up having to unscrew half the frame to spread the frame wide enough to replace it.
Tail belt: getting that sucker back on the gear is a trick.

Lots of little pieces and shims you can't lose. Wires everywhere.

Still not sure how I'm going to swash level this thing. May try the famous zip tie method. Links didn't change so should be a simple matter of subtrimming in the 7200bx setup. May also fabricate a simple leveler block.

 

[Tony]

Yup, they are a pain, but much cheaper to buy parts for compared to a 700 lol. Good luck.

 

[pvolcko]

I've got it back together.

All seems well except for blade tracking. I've got the blade links at the same length but that isn't cutting it this time. Suspecting the plastic blade holders are not exactly true to one another and so I'm going to have to run different lengths to get the blades tracking properly. That or the wooden blades need balancing.

I did my 0 setup on just one blade. Guess I can try doing both to see if there is a difference.

Would blade balance cause tracking issues, or just a vibration?

 

[Tony]

Just vibration.

If you crashed this, then you need to check the feathering shaft. Could be bent. and when you check the pitch, you should always do it on both blades. Keeps from having to chase issues later.

 

[pvolcko]

Checked the feathershaft during post-crash inspection, looked good. Rolled clean. No wobble or fast->slow->fast telltale rolling action. I checked the blade pitch at 0 off the front of the heli on both blades. One was 1.2 degrees off the other. Brought it in to match so hoping will be good now. I'll spin it up tomorrow and check again. Hopefully get it in the air, if weather cooperates.

- - - Updated - - -

I normally do check both blades as a final step, but skipped it this time, figuring since the links were even that it would be good. Live and learn.

 

[Tony]

Another thing to know is to check the blades at the same area. Meaning always check them on the right side of the heli for example. Then, check the left side as well as front and back to make sure your swash is level.

 

[xokia]

I dont depend on the swash level method but maybe I do things wrong. I believe there are such minor changes that a swash leveler just wont dial it in perfectly.

What I do is level the swash the best I can then atatch a pitch guage rotate the head around so the blade links lines up with the servo link. Go around and adjust the servo links until you can rotate the head around and get 0 degrees at each of the 3 locations the links line up. After you do one blade stick the pitch guage on the other blade and repeat. You can adjust the blade links slightly if there are differences.

Maybe I do things incorrectly but its what works for me and the blades tend to track well for me.

I've never had to do any repairs on my 300x because I havent crashed it yet. I had a tip over once but that was it. You can pick these 300's up for so cheap that I would start to question any repair that approached $100. You can pick up brand new 300x's with the AR7200BX stripped for $150 pretty much any day of the week. If you wheel and deal you might be able to get a little cheaper. So before you get to frustrated think about that. I recently sold a trex 250 because I was spending more time tinkering with it then flying it. I value my time significantly more then a lot of other things because I don't really have much free time. So sometimes you just gotta bite the bullet and cut your loses.

 

[pvolcko]

Another thing to know is to check the blades at the same area. Meaning always check them on the right side of the heli for example. Then, check the left side as well as front and back to make sure your swash is level.

I chose one blade and did my swash leveling with that blade around the whole rotation, since I don't have a swash leveling tool for this size heli. After that got that one blade 0 at midstick and then made the other link the same length. Normally I check the other blade pitch, but it was getting late and I had found on the 550 that the link length method resulted in reliable results on that second blade. Didn't work this time, though.

Maybe I do things incorrectly but its what works for me and the blades tend to track well for me. ... You can pick these 300's up for so cheap that I would start to question any repair that approached $100.

In this case there must have been enough difference between the blades or blade holders to require significantly different lengths on the blade links (ended up at 4 or 5 half twists shorter to add some positive pitch to the "low" blade). And yes, if I destroyed it I would probably chuck it and get a 300X minus 7200BX. As it is, I only picked this one up because I found it, with 7200BX, for like $10 more than a new 7200BX by itself. I wanted the 7200BX as a backup in case I didn't want the ikon I am putting on my 700E build.

Just so happened to turn out that I really like flying this 300.

Did my post-repair test flight today. Vid is uploading to youtube now. All is looking good now. Had to tighten up belt tension a bit (tail had too much slop in it), but otherwise was good. Crappy weather here today so didn't get but the one flight in.

 

[xokia]

The 300x isnt a bad heli, to me though it seems under powered. I have the wicked motor and 33A ESC in mine and it still seems under powered to me.
I am by no stretch a pro though. For me it seems like it does each manuever slower then other helicopters I have flown, kinda like a giant mcpx. Maybe thats a good think though because it allows someone more time to react. I'm still practicing 3D on my smaller helis. Once I'm comforitable I try it out on the 300x then move on to the 450. So far all I do on the 450 is flips and rolls and some inverted flight. I've never crashed my 300x or 450............ yet

 

[pvolcko]

Plenty quick for me. It does dog if you put a hard collective or piro on it, but for me that's a good thing.

Test flight after repair: 300X Flights - Page 2