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View Full Version : RC Aerodyne 450 sized 5-bladed head


Skiddz
01-07-2010, 10:48 PM
Got my 450 sized RC Aerodyne 5 bladed with this morning's mail. Feelings are a bit mixed in it right now... The machining looks decent, but the execution makes me scratch my head a bit...

I don't have any bearing play in the swash I got, but there's quite a bit in the swash ball.. Not sure if I can pull it apart to tighten it up or not. Also, the swash bearing is not sealed at all and the balls are open to the elements and there doesn't seem to be much lube in there. That will definitely be a maintenance point to keep checking.

The grip links are just long screws with a brass tubing spacer the ball rests against?? I think I might swap those out for long ball links if I can find some the right size.. Perhaps a standard Align "elevator" servo link installed with the anti-rotation pin towards the grip..

4 out of 5 grips have VERY notchy bearings. Not sure if it's because the bolts are too tight or they're just crappy bearings.. I kinda figured on the latter so I'll pull it apart (which I'd planned to do in any case to Loctite everything) and if I need new bearings, hit up the local bearing supply house for replacements...

The swash follower doesn't look very strong. That's some pretty small hardware and instead of a split collar securing it to the mainshaft, it's a 1mm set screw.. That's gonna require some green loctite to keep in place. Losing phasing in flight would get ugly in a hurry. If the swash follower doesn't pan out, I can draw something up in SW and have my local machine shop mill it for me...

Not a huge issue and will actually be interesting to say the least, but there are no docs to show you how long to make the swash to grip links. Parts are included to build 'em up, but that's it. Just an exploded diagram of the head (sans links) and a parts list...

I guess 1st step is gonna be fitting the head to the heli and get the mechanical setup done... Should prove interesting. Finding scale blades should prove interesting as well.

SidewaysLS4
01-08-2010, 10:01 AM
I just did a bit of maintenance on mine so I'm real familiar with what you are seeing. Let's start with those notchy bearings... Previously I 'tuned' the torque on the grip screws to keep them free-ish, but thought I could do better. So I dug a bit deeper to see if this was an over-torque issue on the bearings with the notchiness or ???. I broke out the 4mm shim set I have and started to play with it trying a different preload on the inner bearing races in relation to the outer races in contact with the grips. I kind of came to the conclusion that either the grips are not machined square leading to a tilt in the bearing when tightened to the hub...or the hub holes are cocked a bit. So I went back to my previous setup, and set it for no slop in the grip/hub, and went with that. You might notice that you can get a section of travel in the used pitch range area that isnt right over a 'bump' in the bearings by turning the grips over and over until you get to a 'free' area, and just use that. Not ideal, but it seems to work ok.

If you find this is a bad bearing issue, post it. I'd be curious, but I dont want to buy bearings to see for sure.

The brass link deal is ok, still solid on mine after around 100 flights so far. Just make sure that swashplate doesnt 'pop' up or down once you get the head assembled and twist the blades, you might want to hammer down the flange to contact the bearing to prevent this as well (pics in the other thread). I'd also recommend putting your servo balls as far in as they will go on the servo horns, then go from there. That should give you a very nice servo travel ratio to the grips.

That swash driver is actually using a M2 grub screw (with a .9mm hex). It might be a good idea to grind a little bit of a flat on main shaft with that type of attachment. I'll attach a photo of my balance job I did on it with a magnetic prop balancer, it uses a M2 screw. Might be an idea to use an actual screw vs. that .9mm hex grub even if you dont balance, might strip out you know...

Flying-hobby.com is supposed to be carrying those new narrow Heliartist 325mm scale blades...sometime, lol. I've been waiting for them for a while myself ;)

http://www.rcgroups.com/forums/showthread.php?t=1134193

Skiddz
01-08-2010, 05:21 PM
I just did a bit of maintenance on mine so I'm real familiar with what you are seeing. Let's start with those notchy bearings... Previously I 'tuned' the torque on the grip screws to keep them free-ish, but thought I could do better. So I dug a bit deeper to see if this was an over-torque issue on the bearings with the notchiness or ???. I broke out the 4mm shim set I have and started to play with it trying a different preload on the inner bearing races in relation to the outer races in contact with the grips. I kind of came to the conclusion that either the grips are not machined square leading to a tilt in the bearing when tightened to the hub...or the hub holes are cocked a bit. So I went back to my previous setup, and set it for no slop in the grip/hub, and went with that. You might notice that you can get a section of travel in the used pitch range area that isnt right over a 'bump' in the bearings by turning the grips over and over until you get to a 'free' area, and just use that. Not ideal, but it seems to work ok.

I couldn't sleep last night so poked around with the head a bit. Looks like at least one grip wasn't drilled out straight.. Laterally it looks ok, but the vertical line is questionable. It might make tracking a bit difficult but should be workable. Bearings all feel ok out of the grips so it might just be a pre-load issue. I'm considering some slightly longer bolts and some jam nuts to set the bearing load then spin the whole assembly back into the head - kinda how all the bearings in a Bergen are preloaded before assembling the parts.

If you find this is a bad bearing issue, post it. I'd be curious, but I dont want to buy bearings to see for sure.

Yeah, I'll look for a suitable fix first, but bearings are cheap from the local supplier.

The brass link deal is ok, still solid on mine after around 100 flights so far. Just make sure that swashplate doesnt 'pop' up or down once you get the head assembled and twist the blades, you might want to hammer down the flange to contact the bearing to prevent this as well (pics in the other thread). I'd also recommend putting your servo balls as far in as they will go on the servo horns, then go from there. That should give you a very nice servo travel ratio to the grips.

I gave the swash a very good "massage" to find any slop and thus far it's just the ball that's sloppy. Good idea on the servo arms. I was thinking a 1:1 ratio might be too touchy with those 3 extra blades.

That swash driver is actually using a M2 grub screw (with a .9mm hex). It might be a good idea to grind a little bit of a flat on main shaft with that type of attachment. I'll attach a photo of my balance job I did on it with a magnetic prop balancer, it uses a M2 screw. Might be an idea to use an actual screw vs. that .9mm hex grub even if you dont balance, might strip out you know...

I do like the balance idea in your pic and will probably implement something similar. (or replace it with something of my own making that uses stock Align radius arms.)

Flying-hobby.com is supposed to be carrying those new narrow Heliartist 325mm scale blades...sometime, lol. I've been waiting for them for a while myself ;)

The shop I got this head from has "flexible scale blades" as well.. I'm going to get hold of Jack @ JMD and ask him what scale blades he's running on his 450 sized 500D.

Debating on whether to try extra tip weight in the blades and go no stabilization or drop the $$ for a stab unit. Kinda leaning towards the latter, especially if I can set phasing electronically, then I can get all the swash/grip links vertical.

SidewaysLS4
01-08-2010, 10:39 PM
I'll say this, my 3 blade version of this head flys very, very nice with a Sk360...I'd say go for it. Nice solid head, and reports say that works best with electronic stabilization. I know it flys better than my CopterX head with the SK, but that is an apples/oranges deal since the 4 blader is a high pitch slow speed (1650rpm) deal vs a high speed, low pitch setup (2100rpm). But then again, I can see the reflection in the blades wobble like a spinning top from 0 pitch to liftoff on the CopterX head with all that flapping going on...and I wonder how much the SK360 is working against that...but that is another subject. Anyway, solid head...excellent platform for a cyclic gyro setup I'd say.

sidneyw
01-09-2010, 12:11 AM
I'd say for ease of flying, 3-blade tops 2, 4 and 5 bladed. The last has the most challenge. Of course, SK360 makes them easy all the way I've heard so many times from several.:YeaBaby: And, HS is whatever makes me happy.

Skiddz
01-09-2010, 04:29 AM
Took the entire head apart tonight. Not a single bit of evidence that any screws/bolts had Loctite on them - in fact, most of the hardware came out with visible signs of oil on the threads... Took a little brake parts cleaner to get all the oil off..

Bearings, when spun by hand actually feel pretty decent, but any "snugness" on the grip bolts gets many of them notchy again. External spacers are within 0.02mm of each other as are the inners so I played with different combinations of inners, outers, bearings, positions on the head etc and got 3 grips absolutely butter smooth and the other two a tiny bit draggy, but not notchy. The drag seems to ease up with a little tension on the grip so I think once they're up to speed, the weight of the blade will pull enough to get 'em nice and smooth.

Grip bolt thread penetration into the headblock is pretty lacking so I'm thinking all 5 bolts will get replaced with 4mmx20mm units. That should allow me to get 3 more mm of penetration and with some threadlock, provide a little more piece of mind that I won't fling a grip in flight. If I can find some short 4mm grub screws, I might be able to start them in the holes from the inside of the head and snug 'em up against the grip bolts and lock them in place for even more security. I'll change the bolts out after a quick rummage through another junk box and/or a trip to the LHS but for now the headblock/grip assembly is good to go.

Swash is definitely questionable. I can move the rotating plate up and down in the bearing about 1.5mm, but I think I can roll the lip over the inner race of the bearing to lock that into position. Can't see a way to take the slop out of the ball, but that might not be that big of a deal. Wosrt case scenario is I buy a new Align swash and haul it to work, chuck it up on the mill and drill the rotating part for 5 blade links and a swash driver link.

I couldn't find any long ball links that were the same length/thread as the screw/spacer/ball grip links, but I did find a pretty close solution. I dove into my 450 parts "junk box" and came up with a couple anti-rotation pin ball links. They're about 1mm shorter than the stock setup, but I discovered the stock spacers aren't the same length with the shortest being 8.63mm and the longest 9.86mm. That would make for some interesting pitch changes and throw tracking all to hell anywhere but 0 pitch. Additionally, the things aren't even close to being squarely cut so they're history. Instead of taking a file to these things, I'll find a few more of these "elevator" ball links and use some 13mm Socket Head Cap Screws and a washer to secure 'em.

Out of the box opinion so far, fair.. Potential to be decent with just a few more dollars and some time, pretty good - I think. :)

SidewaysLS4
01-09-2010, 06:55 AM
This head doesnt need locktite on the grips...really!

The head 'hat' grabs the grip screws when that is tightened down locking the grip screws in place. Give the hat a good crank down and you will see the grip screw thread indentations in the bottom of the hat.

You know, that brass link spacer issue you see sounds sort of familiar...I cant remember if I filed mine to the same length or not, but it sort of rings a bell, hmmm.

satsuma
01-09-2010, 08:34 AM
Would like to think these heads are good, as they look great on, hope all goes well Kevin:thumbup:

Skiddz
01-09-2010, 03:02 PM
I think in the end it'll be good. I really did expect there to be some "tweaking" to make it right and honestly, that kind of stuff is what I enjoy about the hobby. All the fiddling to make it as good as it can be is both relaxing and aggravating - kinda like actually flying the things!

The only "show stopper" I've got right now is - I don't have a .9mm driver to secure the swash follower to the mainshaft! Hopefully I can find one at the LHS when I head out in a bit.

Skiddz
01-10-2010, 03:34 AM
OK, back to Plan A for the blade grips. Didn't want to buy a full anti-rotation bracket "pack" for $4.99 just to get one part out of it and be left with a bunch of parts I don't need so....

I grabbed all the spacers, measured 'em to find the shortest one and me and my trusty file got 'em to within 0.01mm of each other.

Went to build up the links and wouldn't you know it, found one stripped out and of course you don't get any extras with the head... Back into the junk box for a replacement...

Again, since everything thus far with this head has needed a bit of tweaking, every single link is VERY tight on it's associated ball so out with the link sizer and some more fiddling around... and it looks as if the links are too short. With the swash follower touching the bottom of the headblock and the pivot pushed up as high as it can do,the swash, at it lowest point (and probably 25+ degrees out of where it'll probably be phased) I've got at least 2 degrees of negative in the blades and I can BARELY get to 0 degrees by pushing the swash as far up as it'll go... There's no way these links will work.

The pic on the website shows Align style link ends, not the short-body links I got. I don't dare back out the ends anymore, there's not much biting on the link rod now... sigh....

Looks like another trip to the shop tomorrow for parts....

SidewaysLS4
01-10-2010, 09:48 AM
I think I'm thinking what you are writing about...are you using the Trex shaft or the supplied shaft? The supplied shaft gives you 11mm drop in head height from the Trex part, could the suppled links be sized to account for the smaller head height giving you the lack of + pitch?

Thanks for reminding me about the link ends...I broke one origionally also, very brittle. You know, I did order that pack of Clone500 links to eventually replace them all, and some are rather free-threading, and it is 2*F outside....project time!

Skiddz
01-11-2010, 02:44 AM
I'm using the shaft that comes with the head. Not sure which one I'll end up with until I get the mechs fitted to the fuse, but no way these links are going to work as delivered.

I think the lackof length is these link ends. They're much shorter than the Align ones and you can literally only get *MAYBE* 3/16" "bite" into the bodies... Not a whole lot of adjustment room with this setup.

I didn't get a chance to hit the shop today for more links but will head out that direction at lunch tomorrow and see if I can get 5 pairs and see if that helps. If necessary, I can make my own rod - assuming I can find my old spoke threader.

Skiddz
01-21-2010, 09:57 PM
No progress on this head as I got hit with a major project at work and haven't had time to head to the LHS for some longer links. I did E-mail the RC Aerodyne folks about the link length and the only response I got was that my message would be forwarded to a "technical manager". Not sure what's happening now since I haven't heard back from anyone in 9+ days.

Hopefully, I'll be able to get out this weekend and get this thing mounted up to the heli mechs...

Skiddz
04-20-2010, 04:16 PM
Ok, it's been a few months, but I'm back on the job now.. Got a set of scale blades in the mail today. I *thought* I'd ordered the RC Aerodyne blades, but I actually bought the weighted blades from SmartModel. Quality looks ok, but I have my doubts the blades weigh the same. They feel a little different, but I doubt my hands are as accurate as a scale or a blade balancer. :)

Pretty flexible as well and I'm kinda hoping they cone like the real thing when they start creating lift...

I may have the 450 flying with the head and these blades this weekend.

Skiddz
04-21-2010, 10:01 PM
Blades ended at 4 x 32.1g and 1 x 32.2g. Should be able to get 'em balanced up fairly easily. Bad news tho...

The links from the swash to the grips are WAY too short. Even with the swash driver completely bound up, I can't get less than about +2 degrees of pitch. Pretty sure the problem is the cheesy link ends that were provided with the head. I'll dig through my junk box and grab some of the longer Align ends and that should remedy the problem.

I'm going to set it up somewhere around -3/4 to + whatever I can get.. Longer links will help the phasing as well if I want to take the lazy way out (driver at 90 degs to one blade) but I'm kinda thinking I want the links straight up and down which means I'm going to have to use a mix to get the swash to move in an odd manner to get the appropriate phasing.

Sure is a lot of piddly issues to deal with on this head.. Good thing it was relatively inexpensive...

Skiddz
04-22-2010, 12:41 AM
Bolted the blades up for grins.. Looks cool... Swapping out the links on one end to see if I'll get enough pitch range after the swap...

.

helipainter
04-22-2010, 11:02 AM
what mechanics are you using? how in the world do you spin it the other way?

Shuttle RG
04-22-2010, 11:17 AM
A link to the blades?

Thanks! Can't wait to see pics/video of it flying.

Skiddz
04-22-2010, 02:02 PM
what mechanics are you using? how in the world do you spin it the other way?

It's going on my poor 450SE "beater". To get it all going the right way, you just have to pull the one-way bearing, flip it over and reinstall then switch the motor direction. I'm going to change it to leading edge control so the swash moves up with increases in collective pitch - I think. :) The TR flip is going to be interesting as far as servo mounting and linkage goes. Kind of leaning towards something like GoldenRod for that, but I'll tackle that once I get the main head installed and working properly.

A link to the blades?

Thanks! Can't wait to see pics/video of it flying.

I got the blades from Smart Model. http://www.smartmodel.com.hk/products/product.asp?cat_id=143&sub_cat_id=280&third_id=156

Took about 8 days to get here to CA from HK

SidewaysLS4
04-22-2010, 02:58 PM
Kind of leaning towards something like GoldenRod for that, but I'll tackle that once I get the main head installed and working properly.


Good to see your project started again, cant wait to see the results. On the tail flip, a bracket attached to the side of the motor mount with some CF tube going back to the tail works well...not much Goldenrod drag, and balances the heli better leading to less weight needed to balance

Shuttle RG
04-22-2010, 06:01 PM
I got the blades from Smart Model. http://www.smartmodel.com.hk/products/product.asp?cat_id=143&sub_cat_id=280&third_id=156

Took about 8 days to get here to CA from HK

Thanks! Just ordered a set.

Skiddz
04-22-2010, 09:00 PM
Yeah, looking at what might be required to flipt he tail, I think I'd already decided I was going to move the TR servo off the boom and get it tucked up into or onto the frame.

sidneyw
05-25-2010, 10:41 AM
Took me 3 years to make the hat-cam mount. Here are two short video of 3-bladed AS350 using smartmodel narrow blades and 5-bladed MD500.

4-Ymn1jz6PY

lsjDe-tSNsw
(http://www.youtube.com/watch?v=4-Ymn1jz6PY)