Kasama Stuff for the Trex500

[Finless]

Actually much of the side to side play is because the OD of the thrust bearings is loose in the grips. The OD of those bearings is slightly smaller than the radial bearing.
But you are correct also part of the problem is proper compression of the thrust bearing as well. So it is a compound issue.

Bob

[mattkreps]

i don't think my JR 8900 has any prob moving them but i will still do it

[chuckk]

bob,

just received and installed my grips today. i notice that you didn't apply loctite to the threads as per the kasama instructions. i didn't loctite mine due to the nuts having nylon inserts. even if the nuts do back off there's nowhere for them to go due to the design of the grips. a quick grab of the grips on a preflight will reveal any slop or looseness of the retaining nuts. any thoughts on using loctite?

[Finless]

I did apply locktite and I talked about doing it but I didnt show doing it.
But I am sure you are still ok either way since as you point out they are nylocks.

Bob

[chuckk]

ah, maybe a little confusion. i was referring to the locknuts which secure the grips to the hub.

[JodyJ]

I when I installed my kasama grips, I did not use loctite on the nylon nuts that secures the grips to the hub. I flew the bird 4 packs and on the 5th pack I checked the grips and one of them came loose :shock: So I'm going to pull it apart and apply some loctite!

[chuckk]

thanks for that heads up. i dissasembled mine and went over it with loctite.

[Finless]

Just added the new Kasama Trex500 Main shaft thrust bearing block review!

It's in the first posts here but here is a link as well



NEW 4/19 Kasama Trex500 Main "thrust bearing" blocks!
VIDEO -> Kasama Trex500 Main shaft "thrust" bearing blocks review (34 Megs) (http://video.helifreak.com/?subpath=finless/kasama&filename=kasamat550bb.wmv)

[hookmaker]

Bob, any idea how to remove/exchange the bearings in the block if needed later?

/Henrik

[Finless]

YOu have to heat the grips like I show on the Kasama head for the Raptor e620.

Bob

[hookmaker]

Great, thanks!
/Henrik

[MiniCwik]

Just ordered my Kasama tail hub and grips from GrandRC :D

[dxtarl]

links broken

[superbob]

yeah i cant get to the download page either.

[dxtarl]

I found the reason

http://www.helifreak.com/showthread.php?t=83846

[hdskullfire2]

Bob,

When I built my 500 I went with the Align metal blocks over the stock ones. Are the Kasama blocks significantly better? If so I will get most likely do the Kasama Bearing Block upgrade. I just finished the Kasama tail mod and counterweight's per your video. I also just recently installed the TT assembly and pinned the boom per your suggestion. All and all, big improvement with these mods. Flies nice now.

Great vids, great support. Your insight sir....

Steve
Bethlehem, Pa.:thumbup:

[Illusion]

Bob,

Have you tested Precision CNC Aluminium Tail System w/thrust bearings for the T-Rex 500 ? Would be interesting to know how they perform vs. the kasama

Cheers,

[RaptorFlo]

Bob,

First of all, thanks for all the great videos out here, it helped me a bunch getting my Rex500 setup correctly.

I recently got a set of Kasama main shaft bearing blocks, but am puzzled about the way they actually work. The radial bearings are press-fit in the aluminum as you stated that they can be removed by heating up the blocks. Now, if the bearing is not firmly pressed on the thrust bearing during assembly (original or replacement), the thrust bearing will only be loaded once the radial bearing gets a lot of thrust load. Worst case, the radial bearings take all thrust loads if not pressed in sufficiently I´d think..

The radial bearing in the top block in my set seems to have not been pressed down sufficiently during factory assembly, as the top shell of the thrust bearing moves off-center when I spin the radial bearing with my finger.

Should I precautionally heat the bearing blocks and press the radial bearings in a tad more (with centered thrust bearing shell offcourse) to have full functionality of the thrust bearing ?

I think this might interest anybody who needs to replace the bearings as well. Also, do you now have some flight and operational experience with the bearing blocks since the video mini review ?

Thanks,

Florian

[Finless]

You shouldn't need to heat them and press the bearing down. As for the design I too felt it was a little strange but this is how Kasama does their blade grips as well! Check out my Kasama head build video for the E620 and Trex600.... The thrust bearings are behind a press fit radial bearing...

All I can say is both the head design and the main bearings on my 500 are still working well... As to the benefit? Well time well tell..

Bob

[RaptorFlo]

Bob and all,

I just heated the blocks up to 110° C in the oven and gently pushed on the radial bearings. Now the thrust bearing is rotating normally and the upper disk of the thrust bearing stays where it is when I rotate the radial bearing by finger. Seems that original assembly from the factory was just a notch too loose.

By the way: test flew kasama tail with the weight mods + a set of K&B tail blades yesterday.. so much crisper and stronger tail, just awesome!

Thanks,

Florian

[alf_flash]

Hello Bob, amazing video... i bought the Kasama tail, and i did have the tennis effect. But while doing the chinese weight mod i had a problem, using one bolt and 3 nuts, has become impossible to have control of the tension added to the tail blade.

How can i regulate the tension using 2 nuts from one side ?

Thank you very very much !

[Finless]

Not sure what you mean about not having control of the tension?

Bob

[alf_flash]

Hello Bob, once again im sorry to bother, but yesterday i realized the chinese weight mod to my kasama tail, and i had terrible vibrations, specially in the tail linkage and in the boom strunts supports... Why am i having this problem ?

I applied a bigger bolt, 2 nuts and nylock... is this correct ?
God Bless

[Finless]

You must have put something out of balance. Without seeing what you did it's hard to say.

Bob

[Harold Roberts]

Not sure what you mean about not having control of the tension?

Bob
I think he means controlling how tightly the blade grips grip the blades. If so then the answer is to tighten one nut first until the blades have enough 'tension' as he describes it and to subsequently 'lock' the 'tensioning' nut into position with the outer nut. Just as you described on your video.

I have a question about the increase in weight that I can expect with the tail mod. I have a terrible time balancing my 500 because I have a full size servo for the tail (took it from my 600 when I upgraded to the GY611 gyro/servo) and also because my battery is a relatively small TP 6s 2200mah pack. So I already have this pack sticking precariously out the front. I bought a torque tube without thinking about this and now I will have to return it because I am sure my problem will just get worse with more weight in the tail. So if the weight increase is just a couple grams then it probably doesn't matter but if a lot more then I hesitate to upgrade.

Oh, one other question. I have this loud 'squeal' from the heli that was reported when the 500 first came out. Apparently something to do with main shaft bearings maybe slipping within the plastic block or against the shaft. One suggestion was the Kasama bearing blocks would eliminate this. Any opinions on whether this is true? It doesn't sound like you have experienced the squealing 500 though.