View Full Version : Align Low Rider Compass head mod.
Brett74
03-28-2011, 03:06 PM
First of all thanks to Corrari and jrod155 for the idea.
As you can see in the pictures I used the original FBL head and balls links, I turned off 12,85mm from the ball in, leaving 12,45mm from the blade grip to were you bolt on the Compass arm connector, these measurements allow for the original washers that come with the Compass Arm Connector. I drilled and tapped what was left of the ball link in the lathe too so everything lined up.
I then cut 15mm off the the new shorter FBL shaft from Align, this is now 25mm shorter than the older mainshaft. I am running 14,5 degrees of collective and 12,5 cyclic and you can see there is still some room before the swash binds anywhere, note I am using the Quick UK Swash plate which is a fair bit thinner than the Align part so I don't know if you can shorten the shaft this much with the standard swash.
I have just finnished setting up so I will get back with a flight report.
I have also considered the main blades touching the tail blades and I do not believe this to be an issue, there is still loads of clearance.
The only draw back so far is the fact that I lost the use of the turnbuckles I had going up to the blade grips when changed but I seem to have got lucky and the tracking seems OK.
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jrod155
03-28-2011, 04:22 PM
looking good, squatting the head on that thing will help a lot. before I got my compass i was looking to buy a hk600 frame so that i could direct swash to lower the head more and have direct servo attachment.
Corrari
03-29-2011, 03:35 AM
Amazing what you can do if you think outside the box aye.
Looking good brett. Love the blue links and the compass links look great.
I am waiting for a red black swash to finish mine off.
Let us know how it fly's.
I had 'buzzin' Brian Buttler (Curtis Youngbloods designer) look over my heli when he and Curtis were here for the smackdown and he was impressed. More so that some one took it apon them selves to 'play around' with their own machine.
:thumbup:
Brett74
03-30-2011, 07:04 AM
Just got two flights in and definitely made a big difference to the stability, especially inverted.
Couldn't notice any other differences but then the 3G controls the flip and role rate so I shouldn't have either. Great Mod.
My worries about the tracking were silly as you can rotate the delrin rod in it's place which gives you the infinate adjustment to get your blade tracking perfect anyway !
I really want to try this on the 700E but I am wondering if the delrin is tough enough for the extra forces ?
Ah Clem
03-31-2011, 04:41 PM
"I really want to try this on the 700E but I am wondering if the delrin is tough enough for the extra forces ?"
I would wait until the 7HV comes out. Hopefully the new head for that will also allow people to upgrade the Trex 700's to the Compass head.
Brett74
04-01-2011, 05:28 AM
I was thinking the same thing Ah Klem ....What Kinda time frame we talking here ?
Does the 7HV have a simular design just bigger ?
Ah Clem
04-01-2011, 09:25 AM
There have been some photographs posted of the 7HV on this forum. The head is similar to the one on the Atom and 6HV, but not identical.
Compass Team pilots, all over the world, are presently testing the 7HV (and have been for weeks-Compass does not use its customers for beta testers) and pushing it to its very limits.
Only when they are satisfied, and Compass management is satisfied, will the 7HV be released-so I do not have a time frame right now.
I would expect the spare parts to be available around the same time that the machine is available.
Doug Darby
04-17-2011, 08:02 PM
Has been flying great on my 700 for several months now... I replaced the derilin rods with aluminum to keep the phasing tight.
I just cut 19.5mm off my 700 main shafts and will be mounting the "squat" head version this week.
Nice work Brett.. Not sure if you are running VBar, but if you have trouble getting the cyclic resolution in the suggested range during set up you could always use shorter balls on the swash plate and gain some resolution that way.. On the 700 we are using the RAVE swash which is even narrower to help resolution some..
Again nice work...
Doug Darby
04-19-2011, 02:19 PM
My 700 Short Shaft mod is done. If you are interested you can see some pics of it on the 700E forum. ( http://www.helifreak.com/showthread.php?t=298742 )
Brett74
05-17-2011, 10:04 AM
Head for sale in the classifieds...
bwijk
09-05-2011, 09:33 AM
Brett 74.two questions:
Do you use a third bearingblock?
What do you measure now from top of mainshaft ( not the head) to the top of the collar?
Brett74
09-05-2011, 02:15 PM
I am using the third bearing block.
47mm from the top of the collar to the centre of the bolt that goes through the head and the shaft. I have the head on.
I have a set of the pieces I machined to go between the blade grips and the Compass "Y" Connectors if anyone is interested.
bwijk
09-05-2011, 02:22 PM
So i tried it with a fbl shaft today and took 15mm. of. It sure looks cool ! Problem is the max pitch i can do now is 13 degrees. And i really need those Y arms! The washout does not fit anymore, and the ballinks that go up to the bladholders are way to long now.
My only concern is, with the Y arms you would ruin your bladeholder in a crash.Standard ballinks just pop off.