My 800 Trekker Build.

[Curt S]

I will be ordering them this week. I am not a fan of that setup either.

Landing gear works for me. I always take off and land from a hard surface. Well so far landing as has been where I wanted it.

Here are some assembly pics from the manual if anyone is bored.

[hidaven]

Wat are these screw holes for on the top side of the bearing blocks??? Have then in all5)3 blocks. Directions have two on the same side and one facing the opposite direction.....

[nu66ie]

I was wondering the same thing. They are 3mm threads. Maybe there is some sort of support for the bearing blocks on the way.

[hidaven]

Only on one. Side? The manual shows two facing one way and the other facing the opposite way. Very strange.....

[nu66ie]

I actually played with the bearing blocks, inserting a 3mm rod through them. Now that I think of it, maybe I should have left the rod in as I tightened the frame up. It was a little bit of a hassle getting all three main bearings perfectly aligned.

[hidaven]

My last or lowest block was off by a tiny bit. Slight rub going in. Spins fine though so I think im ok. I also found those freakin links off and not close to 2mm! One mm at best. Lets hope the stuff we can't see is at spec. : )

[nu66ie]

Are you talking about the elevator pushrods? Mine were off as well.

I found that the carbon fiber spacers where the elevator servo is mounted to the aluminum cage was hitting the top and middle main bearing. Cutting the corners off those helped but I still had to slightly enlarge the three holes in the frame (both sides) where the lower main bearing block attaches to the frame. If I bolted the three bearing blocks down completely first before adding any other bolts, I'd get perfect alignment but I could feel allot of tension in some of the other bolts.

Only one frameset was like that, the one on the other heli fit perfectly.

[PHANTMXR6]

Man there's a lot of shims on that main shaft.
Is it meant to have that many?

[hadi10]

hey all.
i am also currently building my 800dfc .
after i installed the motor and main gear with a correct mesh.. its pretty heavy to rotate the main gear by hand ..!! is that how it should be ..??!!

[hidaven]

Nu can chime in, I used 2 shims to keep that bottom black collar snug against the main gear. My shaft end sticks into the 3d bearing block about 3/16 of an inch. And yes the motor is on the harder side to turn the gears......

[nu66ie]

I only used one shim and that was the thinnest one on both 800e birds. That many shims does not look right. At that height, you shouldn't even be able to get the jesus bolt in. I could spin the main shaft with only a little effort.

[hidaven]

Wow, is there supposed to be any play when the shaft is all the way through and the Jesus bolt is tightened? I have no play whatsoever on mine up and down......if I use one shim I get a little play up and down.....maybe the jesus hole was cut too high on my main gear?

[hidaven]

Update. Called align and Tim said the they just built one and it too needed the large plus thin one. I still have about 3mm of the bottom shaft sticking into the bottom bearing block. I'm raised about 1.5mm higher using the 2 shims. Some added protection from a boom or tail strike. : )

Question, I installed the middle bearing upside down. Aside from it being a little harder to oil that bearing is there any need to reverse it? I have all 3 facing up instead of the middle one facing down......and did you all grease the one way bearing from the inside or take apart and do the outside. I may use the triflow oil as I read the its not a bearing per se but a clutch and its better to use triflow or ATF........

[nu66ie]

The middle bearing block should be upside down compared to the top and bottom ones. If you have the middle block right side up, the OWB will push it through the block and bad things would happen.

When the middle block is upside down and the top block is right side up, the pressure between the collar on the shaft and the OWB pushes the bearings toward the bottom of their respective blocks keeping them seated.

When oiling the bearings, dropping the oil just inside the outer race from the top or the bottom of the bearing will have the same effectiveness.

The main shaft on these are flush with with bottom of the bearing on the lower block. Looking at it from below.

Hope that makes sense.

I use only grease on the OWB, no Tri-Flow as it thins the grease. Do not over oil the main bearings as the oil will eventually run down into the OWB. I've seen helis with oil on their batteries as it has run all the way down the main shaft. It just takes a drop or two every three or four flights.

I service my OWB every 12 flights. Taking it out of the hub, cleaning the old grease off and re-greasing it. Make sure it is put back in the correct orientation. I have yet had one fail on me... Except for the time when I used Tri-Flow only on it early in my heli flying days. It's been only Lucas Red "N" Tacky #2 ever since.

[hidaven]

Dear god! Thank god I posted that pic of the bearing block screws and that guy caught the 2 additional spacers!! Middle bearing block was upside down and apparently a little thicker on the other side! Now I too only need the one thinner spacer and the end fits into the 3rd block deeper. Whew. Thank god for folks like you all or who knows what would have happened......I also needed to re tighten those pinion set screws! Thanks nu. I also needed to lower the pinion so the tip rests on the bearing......can't believe I overlooked those two things! No more marathon building sessions for me. I'm going over every step to make sure I didn't miss anything else......

[PHANTMXR6]

No worries mate. Glad I could help.

[nu66ie]

Glad you got it figured out. I actually flew my first 700 for a few minutes with the middle bearing block right side up. After landing I noticed play in the main shaft and I knew right away what happened...

When you reset the pinion height, it's hard but try to get about a .01mm space between the pinion and bearing. Those bearings will wear out fast if there is pressure on them. It make a wicked noise when it goes...I use 0.1mm spacer from the tail grips and lay it down on the bearing and let the pinion barely rest on it.

Good Luck!

[hidaven]

Can I just leave it a hair above it? Why does it have to make contact?

[nu66ie]

.01mm is a good gap between the pinion and bearing. I know the instructions say to have it touching, but in the 700e with the pinion touching the bearing, the bearing will let go after 20 flights or so of hard 3D. I don't think the 800 would be much different. Apparently the motor shaft will travel up and down under hard stops. I read that on another forum.

I just bought one of these for that reason, to measure small gaps.

[hadi10]

i also think it gets pretty over heated from friction..and that can damage the bearings easily.. thats what happened on my fusion50