HC500 owners... need some input.

[Blayd]

Its winter so I've been tearing down, greasing, and replacing bearings, checking links, all that good stuff.
Mines still flybarred.
Well, I've been wondering about redoing the head on my HC500....
My main shaft has the Jesus bolt for the main gear hub, in the second hole of the main shaft. The reason I was thinking of redoing the head set up, is...
Right now, I can only get barely +/-10° in pitch on the head, and when I'm in full negative, ( -10° ) I am only able to apply so much aileron before the swash bumps the collar. Any more positive pitch, and the washout block is up against the head block.
I guess I was wondering.... how many guys are flying with the mainshaft in the bottom hole? the second? Any flying in the top hole?
I was thinking if I move to the bottom hole, I could get more shaft to travel, not sure I can get the links to all line up.
So, first things first... you flying the bottom hole? or second hole?
If I remember right, 60Something told me he was almost sure he flies the bottom hole. One of the techs at HD couldn't remember which hole he is flying. ( he flies 2 HC500's )

Let me know....if any HC's are still flying...

EDIT::: One of the reasons I was looking at redoing the head.. I was told that this bird was capable of getting much more pitch then this as per Charlie and Henry.

[Blayd]

OK.. guess I'm the lone HC500 flyer huh?
Well, just in case, heres my plan....
I have enough parts to build a second head. I'm going to build one, and use it to see what installing it in the bottom hole will give me...I guess since I'm setting up a second head.. I might as well go with the more advanced linkage ball placements. This way, if I can figure it all out, I'll have a sport head, and a 3D head.

[jacquesjb]

I am flying mine with the mainshaft in the bottom hole and I have +/- 12 degre of pitch.
You can have more pitch also using the more inner hole of the main grip blade.

[Danimal]

I'm defiantly using the bottom hole and running a +/- 13 pitch. We had a conversation with Charley a couple years ago about this. And this was the setup he was flying. You are still going to have the issue with the swash travel. Its not a big deal though. Your just going to need spend a little more time programming the cyclic through's.

[Blayd]

Thanks guys...
Danimal....did you need a spacer between the gear hub and the bottom, main bearing to use the bottom hole? Just wondering. Right now, as it sits, using the middle hole.. I barely have +10°~ -10° Collective pitch. And even then, if I go full negative, the swash is so close to the frame/collar, there's not much cyclic available before the swash hits the collar. The guys at HD told me, that in this position, ( swash full negative, throwing full aileron/elevator ) its just not a realistic situation. I don't know...I was always under the impression, I should be able to throw the sticks full range in any situation with no interactions, like my Trex's.
Sorry for the questions.. I flew this 500 all last year with my beginners set up of -5°, 0°, +11°.. but I've been flying -12°~+12° on my Trex 500's.. and I know Charlie and Henry designed the HC500 for alot more capable pitch then barely +/-10°.
Well, I'm building a second head today, going to use the inner ball link holes as well as trying to fit the head on with the bottom hole. Lets see what I can get from this thing. I'm no where near ready for 3D yet.. but I still want it capable of its potential.. then I can dial it back. Both my Trex 500's easily have +/-12° collective pitch, and I'm flying 8° cyclic. And fly really well. My worries right now are..
Will the links let me go this aggressive.
If you guys have more info.. I'm all ears....I absolutely LOVE this machine. And plan on making full use of its capabilities.
Thanks.

[Danimal]

No I didn't need any kind of a spacer. The auto sleeve comes out the top of the tail pulley enough to shim the assembly off the bearing block. The guys at HD are right.You have to limit the cyclic through's in your TX so you don't rub the swash on the collar at full negative. Its not that big a deal. After you get the shaft reset to the bottom hole you will need to rebuild the linkages. At 0 pitch mid stick adjust the links so that all the arms are flat level and 90 to the shaft. You should be seeing way more than =/- 10. In your TX(ARF) swash functions rate settings (sorry I don't know what Walkera calls this I fly Futaba) back down your pitch through till you get the range your after. At full negative give aileron and elevator inputs and adjust those till you can give full stick inputs with out hitting the collar. You'll still have enough cyclic travel to make the HC as fast and snappy as you would want. One more thing. What head speed are you running? This heli really likes high HS. I'm running about 3170. I've had it higher in the past. But it was just to much for me to handle. I'm not a smack down 3D pilot.
I've added some pictures so you can see the amount of cyclic through I get at a full stick +/- 13. keep an eye on the phasing pins. Don't try and get so much pitch that you run the washout off the pins. And a picture of the main gear bottom bearing block.

[Blayd]

Hey Dan..
thanks sooo much for the great info.
I know how to get the linkages right at 0° mid stick.... I'm just really worrying about the very little amount of cyclic movement on the swash right now at -10°. But, i'm still in the middle hole. At mid stick, I have about 6 or 7° cyclic pitch in aileron...thats it.. enough to fly with, but at full negative ( -10° ) its alot less or the swash hits the collar. I'll take it to the bottom hole, this weekend, see if I can get things worked or on the linkages, and see how it works out. GREAT info.. cant tell you how much the pics and your input means.. I love this bird, but my biggest issues have been interactions in the head... full aileron + full negative or full positive and I get things hitting in the grips and cage. If I back down my swash mix in the Tx, I start getting to like 40%, and have a really hard time with that percentage, to get a good cyclic pitch. Driving me nuts. I'll try a complete redo on the head with the bottom hole. See how this works out.
I was trying to see your links.. wanna make sure the linkage rods will work on this as they come in the kit. I'll wind up having to lengthen all the rods in the mixing arms to make the bottom hole work. We'll see...THANKS!!!

EDIT::: Head speed... about 2600... using a Scorpion 1400, 14T, and 5S batts. ( Beginner ya know...didnt want any blazin head speed right off..)

[Blayd]

By the way.. got some nice guitar parts there...I got a bunch of gits/amps/pedals myself...

[Blayd]

Hey Dan,
Got another question.. ( sorry man.. I didnt think of this until I started looking...)
What about the notch for the grub screws of the collar, in the main shaft? I havent tried yet, but when you go in the bottom hole, does the notch still work for the grub scews in the collar? I was thinking, even if they dont, its no big deal to lengthen the slot in the main shaft, or even not use the slot at all. My Trex doesnt use any slot in the main shaft for the collar. Just wondering.
I'm going to try to mess with this this weekend...
One issue is that I made a .050" spacer to go between the gear hub and the bottom main bearing.. this keeps the belt dead center of the tail gear, instead of the belt riding at the bottom of the tail gear like the stock set up on an HC500...
I posted a few pics.. ( soory for the blur..I'm as good a photographer as I am a heli pilot..) I am posting a few to show where the antirotation pin is at in the bracket at low, mid and high stick in idle up as it is right now...was wondering where your pin sits in mid stick?
Thanks again.
Mike

[Danimal]

Don't apologize for asking questions Mike. That's why we'er all hear, sharing the hobby.
You shouldn't have any trouble with the grub screw. That notch is more than long enough to accommodate using any hole in the shaft. I've never had a problem with the belt riding low on the pulley. That shim you installed is going push the the shaft down and take away from the total pitch range you should have gained from moving to the bottom hole.
I tried to get some pictures of the travel of the anti-rotation pin on my HC. But my camera is giving me a hard time with the flash so they aren't vary good. I hope you can get an idea of what yours should look like from the crappy pictures.

[Danimal]

PS. When I took the first pictures I didn't even realize the guitar stuff was in there. Its another hobby. We build custom rigs and do repairs. Check out this blank. Its going to make someone a beautiful guitar. But its not going to be cheep. That one piece of wood cost me almost as much as my nitro 50.

[60something]

Ok, so NOW you finally do the pics I asked you to do 3 months ago... LOL!

You don't have enough swashplate travel, and your swash is set low, plus, you'll get more head action if you move the balls on the washout arms to the outer hole. But be careful, sensitivity will increase significantly.

If you're using the 2801 still, set the SWASH setting to about 58-60%. All three values should be the same if you are using the same servos, but the actual value will depend on what brand of servos are used with what radio system. The ability to vary these values is used when, at the range of travel, the servos don't quite move in unison, ie swash not level through the stick movement range. Make sure in TRAVADJ that PIT is set to 100% - this is where you limit overall travel of the swashplate and can dial in unequal pitch range. PIT sets endpoints; SWASH changes PROPORTIONALITY of the swash movement.

With those two settings, you now choose the shaft hole that places the swash at 0 deg midshaft travel at mid collective stick and spacer out as necessary the shaft above the pulley as needed. Now, depending on the servos you have, you need to select the servo arm ball position that give you the full range of movement you desire. Control range is always done in linkage before you twiddle the tx settings. You use the tx settings to adjust for what you can't accomplish in linkage.

In my case I'm using the centre of the 3 holes in the FG servo arm, and the bottom hole in an original shaft (I haven't measured the hole positions in the replacement shafts that are slot machined to see if they're different). I've rarely seen a link rod setup that matches the length measurements in the construction manuals for anything, although some will get you in the ballpark. Then, you can tidy up the movements with the SWASH, SUBTRIM, and TRAVADJ functions if necessary.

At that point, if you have full travel of swash, and you have significant cage interaction, you can limit overall collective travel with PIT, and cyclic travel with AIL and ELEV, all in TRAVADJ. Its pretty rare to ever use so much collective and cyclic travel together that the swash and cage interact - the heli would be very difficult to handle in hover - you'd wind up dialling in so much expo in D/R to tame it that it'd be unflyable IMO. But then I don't fly instant-kitting 3D...

[Blayd]

Hey Paul, Good to see ya.
Hey Dan,
I went to the bottom hole, got the head reset up. That was actually the easy part. No work in the Tx or anything yet.
I've spent the last 5 hours trying to get the damn wobble out of the gears.
Still havent got it yet.
I slid the main shaft to the bottom hole, ( the notch in the main shaft doesnt reach that far down...so for the time being, I just tightened the grub screws on the collar )
and adjusted the links to get the swash, mixing arms level at mid stick.
I went to spin it up by hand to watch the belt on the auto gear and saw the wobble.
Figured this was as good a time as any to pull the shaft again, and check it for true. Its straight..I even rolled it with three new ones to check. Its straight. So I put it back and started looking at the hub. Swapped the sleeve, no good. Wobble is there. I tried to loosen the bolt, and "bend" the auto gear, and re-tighten the bolt.. no good. Made it worse. I think I am just going to have to rebuild the hub and gears again.

[60something]

What's the wobble in - main or auto pulley?

[Blayd]

Hey, sorry it took me so long to respond guys....been a really bad week, here.. both kids sick.. ya know.. stuff.

I got the head set up with +/- 12° collective and about 7° cyclic right now. Main shaft in the bottom hole.
I put the spacer back in..otherwise I could probably get 13+ in collective easily.
The wobble... this really had me stumped.. still does.
After putting the main shaft in the bottom hole, and redoing all the mixing arms.. ( I elected to keep the ball link in the inner hole of the mixing arms..so.. theoretically, I may have been able to get even more out of the head.)
I put the gear set back with no spacer, and spooled it on the bench, first by hand.. noticing, the main and auto gear wobbling, but this was also showing up, slightly in the swash. So, I pulled the main shaft, and rolled it on my glass that I use. It seemed straight.. so I opened two packs of new shafts to confirm it... yep. Its straight.
Next I built a new gear set, new hub, main and auto gears. Same result. Next, new main bearings. Same wobble. I spooled it with the motor.. no doubt about it... it had a wobble vibe, if I had blades on it.. it would have been bad. Next, I ditched the main shaft and replaced it with a new one. I also messed around with the tightness of the bolt in the gear set to the main shaft to see if I was over tightening it. Still had a wobble.. but greatly reduced. I changed the sleeve, and tried to "straighten" the gears.. and got it to a minimum. I decided to reinstall the spacer.. I just couldn't let that belt run on the bottom ledge of the auto gear like that.. ( compulsive/obsessive to a fault!!) Surprisingly, the belt is back to dead center of the auto gear, and the wobble is minimal right now.
I took it out yesterday and ran 3 batteries through it...there was a pretty constant breeze blowing, so I did nothing more then hover it.. and move it around a little.
I had a time taming the HC500 down last season.. running both, a little EXPO ( 30%) and some D/R, ( 15% ), now that the head is in a new position, and I have +/-12° collective, its once again, a handful. Not uncontrollable, but definitely back to being a seriously fast responding machine.. especially in cyclic response.
I watched it in idle up ( I fly in idle up 1 most of the time..) with a flat TC of 85%, from spool up to sitting on the ground at 85%throttle... no visible vibes, but in hover, I need to get used to the new pitch curve.. very fast in both aileron and elevator.
Present swash mix right now in the 2801 are PIT 58%, AIL 60%, ELE 60%.
I was also testing my Rex 500 after redoing its head and pitch curve,as well as an ESP 500 I built, from a used frame I got, here with a new PRO head and PRO tail unit.. its also my first Torque tube tail.
The wind was killing me.. I didn't want to push my luck.
So, it flies... seems stable.. hovered with no drift, looks like I just need to get used to the new feel.
I'm still a little nervous how low the swash sits when in full negative..I really don't have much more room to raise the swash up before its hitting the washout block..but, this is full negative... beyond trying to climb out inverted or recover after a flip, I wont be flying in full negative...but after checking, even with about -7°, I can still smack the collar in full aileron. If I Try to dial it out in the Tx, I wind up with less cyclic pitch.
I'm going to keep tweaking it, but for now, it is flying in the bottom hole, with a better range of collective. I'm not sure what I'm going to do about the wobble...I've gone through a box load of gears/hubs/sleeves to get it this minimal....not good when supplies are getting low on these...

[60something]

Originally Posted by Blayd

I had a time taming the HC500 down last season.. running both, a little EXPO ( 30%) and some D/R, ( 15% ), now that the head is in a new position, and I have +/-12° collective, its once again, a handful. Not uncontrollable, but definitely back to being a seriously fast responding machine.. especially in cyclic response.
I watched it in idle up ( I fly in idle up 1 most of the time..) with a flat TC of 85%, from spool up to sitting on the ground at 85%throttle... no visible vibes, but in hover, I need to get used to the new pitch curve.. very fast in both aileron and elevator.
Present swash mix right now in the 2801 are PIT 58%, AIL 60%, ELE 60%.

30% EXPO is a LOT of expo, not a little - a little is 3%. Set up your D/R to limit the cyclics a fair bit then bring the cycle D/R up bit by bit as you get a hold of it. Ultimately your EXPO should be down to less an 10 (or even lower) Use the D/R to give a "relaxing" setting. Why is PIT less than the other two?

I'm still a little nervous how low the swash sits when in full negative..I really don't have much more room to raise the swash up before its hitting the washout block..but, this is full negative... beyond trying to climb out inverted or recover after a flip, I wont be flying in full negative...but after checking, even with about -7°, I can still smack the collar in full aileron. If I Try to dial it out in the Tx, I wind up with less cyclic pitch.
I'm going to keep tweaking it, but for now, it is flying in the bottom hole, with a better range of collective. I'm not sure what I'm going to do about the wobble...I've gone through a box load of gears/hubs/sleeves to get it this minimal....not good when supplies are getting low on these...

THe swash is shaped to sit down over the collar - grease the top of the collar if you're worried about it , or use the PIT function in TRAVADJ to lift the swash a bit at full down to keep it off the collar.

You'll likely find that the gears smooth out with running - mine did. Took a few dozen batteries, but the whole gear train settled right down to being smooth eventually. If the shaft is a tad undersize ( I tried a couple of mine last night- they're a gnat's wisker looser than I would like, so correct tension on the bolt is important. If you have access to a small lathe, you can clamp the gears/sleeve assembly in the lathe, and with the gentle use of a heat gun (and a dial indicator if you have one), you can coax the wobble out of the gears.

[Danimal]

You can also tame down the cyclic response with some different paddles or perhaps some flybar weights. Adding weight will slow down the response. The heli will become less sensitive and more docile. Then you can back off on that EXPO. Then when your ready and want to speed it up its really ease to do.

[Blayd]

Thanks for the replies guys....

The speed of the cyclic isn't intimidating enough to warrant any serious actions.. but just very noticeable. hovering is the most I've noticed it.. in FF, its just very responsive.. it really feels like it WANTS to do more then just sport flying.
60.....
The aileron and elevator in swash mix was left alone...mostly because when I checked cyclic pitch, and elevator pitch, I was getting 7° cyclic, and, if I remember right, 6° elevator pitch. ( don't hold me to that number.. I'd have to recheck it..) When I dropped the aileron swash mix down, I lost cyclic pitch. Same for elevator. That WOULD relieve a slight bit of the swash, in low stick, hitting the collar when I go hard aileron.. but only slightly, and didn't want to give up cyclic pitch for a situation that may never occur? I was under the impression that 7° cyclic pitch is a beginning point for cyclic pitch...so didn't want to loose any..if that makes sense.

The gears....
Yeah, last year I had the same issue..remember? Went through a handful of them until I took the least of the bad ones and used them. The set on it now are OK...and yes.. the last set did sort of "wear in", but the first set I had on it, had enough of a wobble to really shake the heli as it spooled up...it would smooth out as it got to head speed, but keeping a finger on the boom.. it was clear the gyro was gonna be feeling a good steady buzz from the gears.
The set on there now isn't too bad.. the heli doesn't have a wobble or bounce as it spools up...and the tail doesn't show any signs of vibes so for the moment, it seems OK. I just hate going through my stock of gears and hubs and sleeves. By the way, so far, two times in a row now, the black Main gears from CNC are the straightest. The delrin gears have a flat spot in the between the spokes. If you put it on a main shaft with a sleeve, and turn it, watch from the side, you can see the teeth/rim, moving in and out, corresponding with the spokes...which, is really weird, because, I thought the delrin gears were CNC.
And just for info...the main shafts I have, you can use the stock notch cut in them, if your using the bottom hole. I had to take my dremel and grind them longer. Not a big deal, I have to do that for my Scorpion motors anyway.. just info.
Oh and yes.. I DID notice the main shaft has more play in it then I liked as well, between the sleeve. Again, not a big deal. But its enough to be able to move, or "tilt" the gear set a little when its installed. I had noticed it last season. That's why the tightness of the bolt is something to watch. I just snug it up, make sure its loctited. Not tightened too much. Otherwise, it would be easy to "clamp" the sleeve down on the main shaft and making it out of round.
Paul, you and me need to have a discussion, ( ya, ya, I know...how many times you gonna tell me....) about swash mix, cyclic pitch, and and using travel adjust.
I was under the impression, that swash mix was used to get total pitch range, ( 20°, 24°.. whatever ) and you get your cyclic pitch and elevator pitch with the swash mix AILERON/ELEVATOR percentages, and that Travel adjust was for taking out swash plate interactions..once you level the swash at 0°, you go low stick...if its not level, you add or subtract in travel adjust for that servo, same for high stick??
If I use travel adjust to get my cyclic pitches, I wind up with my swash not being level in high stick or low stick???
Well, that'll be for another time. Once again, I've gone on and on and on...
Thanks for the help guys....
I'm really hoping to get the HC500 as comfy as the other two 500's...I have yet to hover nose in with the HC500...its just a little too hot... and yet, My nose in on the other two 500's is second nature.
Thanks Dan, Thanks Paul!

Mike

[Blayd]

Oh and Dan,
Seriously nice piece of wood. Stuff like that is hard to come by anymore. I dont build 'em, I just play 'em.

[60something]

Paul, you and me need to have a discussion, ( ya, ya, I know...how many times you gonna tell me....) about swash mix, cyclic pitch, and and using travel adjust.

We'll talk... The answers are in my post above.... SWASH is the COLLECTIVE mixing adjustment tied to the swash mixing method you chose on the front screen (3servo -120 deg) and linked to the throttle stick Has nothing to do with cyclic action - that's controlled by servo arm length and TRAVADJ (the old "end point adjustment" on older TXs.

You set collective mixing proportionality movementwith the SWASH percentages (independent of TRAVADJ), but the swash percentages allow you to adjust the PROPORTIONALITY of the movement of the three servos independently, in case they don't move by the same amount per stick action (and why the percentages should ordinarily be the same unless you are using diferent servos or, the ball positions on the arms are not at the same radius).

In practice on most heli radios, due to the 1520 ms neutral time base, works out to around 60% for most systems. These adjustments allow you to set up for a level swashplate through the throttle stick movement range.

Proportionality of collective action itself about 0 degree midpoint is adjusted in pitch curve. ( eg -5, 0, +10). You can fine tune the end point travel of the collective pitch range on all three servos using the TRAVADJ PIT function. If its bumping the head, you back off the TRAVADJ PIT from 100% at one end to bring it down. If its bumping the collar, you back off the other end. You can also stretch the movement by going over 100%, but that's generally not good practice unless you can't make the appropriate servo arm adjustment. It sometimes takes a bit of fiddling to balance SWASH percentage and TRAVADJ PIT settings.

For cyclic action, you adjust the TRAVADJ ail/ele to limit or expand ail/ele end points according to your need.

It all starts with the linkage. Servo ball location, head pitch arms all have to be set up first. It can be a bit of a compromise to find the best settings of the servo arm balls to achieve an optimum position for both collective action and cyclic action. On the HC500 - the middle hole is the best place to start. That's why the tx has so much flexibility for range and end point adjustment.

Next, set up your collective movement through SWASH and TRAVADJ PIT to get the range and proportionality you want on the throttle stick and in regard to the position of the swash on the shaft, adjusting linkage arms to keep SWASH to around 60%. Check for level movement of the swashplate over the range, and adjust with SWASH percentages if the swashplate doesn't stay level. You can use the SWASH percentages to limit the overal range, but you must maintain the proportionality between the percentages if they not all equal. When done, the swashplate will move through its full range in proportion to the throttle stick (assuming a linear pitch curve - set all curves to linear until you get the servo/swashplate/head movements all dialed in. Remember - SWASH and TRAVADJ are mechanical setup functions. Throttle and pitch curves are flight setup functions that can only work with the limits set by the mechanical setup.

Once the collective is sorted out, you then move to cyclic action. You set the overall mechanical cyclic range (limited choice) with the mixing arms, then adjust limits as necessary with TRAVADJ in ail/ele. These adjustments are independent (mostly) of the collective/swash setup.

You then set up your pitch and throttle curves in the three available modes to balance action and power relationships for actual flight.

Finally, you use EXPO and D/R to set up stick reaction parameters for cyclic control to suit your flying style for the flight mode you're in.

If the bird is properly set up, you will ultimately use little expo (except in extreme 3D, when anything is possible), and you may or may not need D/R depending on how much sensitivity is mechanically dialed in and/or limited by range and endpoint settings.

Your intiall learning phase for good heli control is to have the stick and your fingers match the action of the heli so that you have good flight control that is consistent with your natural finger movement on the sticks. You use larger expo and D/R initially to limit over-compensation, but you should be reducing both as you progress until you are down to the minimum amount needed to balance your finger response and the "stickiness" of the sticks around neutral. THEN, as you progess into more advanced manouevers, you will start work back out with expo and other combinations for specific flight actions, rather than simply to tame dumb thumbs.