Logo 690SX question

[rcflyerheli]

I just disassembled the tail hub/grips on my 690SX to do some routine maintenance and found that there is no washer under the screw that holds the grips in place.

Went to the parts catalog at Mikado USA and looked at the replacement hub with screws and again, the photo does not show any washers associated with the hub/bolt. The manual most specifically shows a washer between the head of the bolt and the outer race of the thrust bearing.

Any ideas on the true skinny on this?

[rcflyerheli]

Has no one else seen this issue?

[Crowbar]

I'm building a 550SX v2 and found the manual to be very vague about the washers/spacers/shims. I think they want to tell you where the washers shall go if you got some axial play.

Or maybe the newer version has a slightly different design with washers and you got the old version. It's hard to know what version you have and what version the replacement part is.

[KevinB]

Sorry........I'm using QuickUK tail grips.

KevinB

[pwood]

Hi

You may find this interesting:

http://shop.mikado-heli.de/LOGO-Heli...&c=3743&p=3743

It is on the Mikado site for the 600. Part #727 looks like it includes the ship you are looking for.

Regards
Paul

[rcflyerheli]

Originally Posted by pwood

Hi

You may find this interesting:

http://shop.mikado-heli.de/LOGO-Heli...&c=3743&p=3743

It is on the Mikado site for the 600. Part #727 looks like it includes the ship you are looking for.

Regards

Paul

Thanks for the reply. I see what you are referring to and in that depiction, it shows a washer that goes under the head of the bolt that holds the grip onto the hub. But if you go to page two of the reference link and look at part number 4069, which is the tail hub and grip with all bearings and bolts, they do not show a washer between the thrust bearing and the bolt.

The reason this all came up was that I have two tail units, one for my 600SX and one for my 690SX. The hubs and thrust washers for the two are completely different.

The one for the 600 uses a weird type of thrust washer with a conventional inner race and ball race, but with a big thick heavy outer race that is similar to a flanged bearing. The ball race and the inner race both go over what would be the bearing (if it were a flanged bearing) and ride on the groove that is machined into that thick outer race. That whole unit goes onto the tail hub and mates against the thrust bearing washer/shim. The thickness of that outer race is double what you would ordinarily find on the outer race of a thrust bearing and there is no washer between it and the retaining bolt's head.

The 690SX uses a conventional styled thrust washer with a stepped tail hub for mounting but also has no washer between the outer race and the bolt head.

I did go ahead and install a 3mm ID x 1mm thick washer on the outside of the outer race per Mikado's suggestion.

Again, thanks.