Optional crown gear for MD7/8 + interesting turbine MD8

[FREESTYLER_LB]

Check out this optional crown gear for the MD7/8 . It has a full CNC insert . Matt designed it and it looks real good . Here's the link with photos . It's translated from Chinese https://translate.googleusercontent....3Py5OWj5bY_0-g .

I was also searching some MD videos and ran across this turbine MD8 . It's the first one I've ever seen . I would like to put a turbine in my MD8 someday but I got a whole lot of research and saving to do beforehand lol .

Kevin MD 噴射800 (2 min 46 sec)

[ChuckL]

I wonder what's the benefit of the new gear.

[FREESTYLER_LB]

Originally Posted by ChuckL

I wonder what's the benefit of the new gear.

From what I understood out of the roughly translated article , it looks like it prevents the twisting and warping of the crown gear when using those supercharged power setups . It probably also helps with the gear strength and alignment maybe ? I don't know for sure , but I guess I'll be able to say more once the new gear actually arrives . It should be here maybe Monday . Matt has been using it for quite a while now and he said it worked great so that's good enough for me lol . All in all I don't think it'll hurt anything ?

[rfauske]

Its reccomended with the md8 to use the carbon fiber spacer for the auto gear.

With the new gear its not needed, have been using this auto gear the last 6-7 months or so with great success on my 3 blade.

But just as a note, there is nothing wrong with the original this is just a bit better way of doing the same thing

[FREESTYLER_LB]

Originally Posted by rfauske

Its reccomended with the md8 to use the carbon fiber spacer for the auto gear.

With the new gear its not needed, have been using this auto gear the last 6-7 months or so with great success on my 3 blade.

But just as a note, there is nothing wrong with the original this is just a bit better way of doing the same thing

Is this the carbon fiber spacer you're referring to ?
http://www.mdhelicoptersusa.com/Uppe...acer?limit=100
I've used that one for a couple of flights but then I removed it because for some reason it was causing friction and rubbing between the main gear and crown gear . I messed around with it trying to resolve this but couldn't get the head to spin without friction . The only way I could stop the friction was to slide down the bottom clamping collar of the main shaft but I didn't like having that collar halfway engaged and the other half just hanging out of the shaft , just didn't seem safe at all . I'm sure there was something I missed or did or didn't do but I just gave up in the end and removed it .

[ChuckL]

I'm sure that's what he was talking about, maybe some have slop without it. When I built my 800 I didn't use it and mesh feels just like my 700 which is perfect.

[FREESTYLER_LB]

Originally Posted by ChuckL

I'm sure that's what he was talking about, maybe some have slop without it. When I built my 800 I didn't use it and mesh feels just like my 700 which is perfect.

Thanks ChuckL , yes the mesh was great on my MD8 even before attempting this but I still tried to make that carbon fiber spacer work for me nonetheless . I guess I should've followed the good'ole saying "if it ain't broke don't fix it" lol .

[mdhelicopters]

The carbon main gear spacer is not necessary and will actually cause friction between the main gear and crown gear.

the best thing to do is instead of using the brass washers with one of top and one on the bottom of the main gear, put them both on top so that they are both between the main gear and crown gear. by doing it this way, you will get a much smoother rotation on the auto gear when the main is not spinning.

the new crown gear and hub style was a culmination between us and the factory due to the molding process of the other red crown gear may not have seated on the hub flush due to ejection pin misalignment, so the new style gear and hub has resolved that issue, plus also helps with keeping the gear true on rotational axis.

ive been flying them for quite some time with 0 issues now...

[FREESTYLER_LB]

Originally Posted by mdhelicopters

The carbon main gear spacer is not necessary and will actually cause friction between the main gear and crown gear.

the best thing to do is instead of using the brass washers with one of top and one on the bottom of the main gear, put them both on top so that they are both between the main gear and crown gear. by doing it this way, you will get a much smoother rotation on the auto gear when the main is not spinning.

the new crown gear and hub style was a culmination between us and the factory due to the molding process of the other red crown gear may not have seated on the hub flush due to ejection pin misalignment, so the new style gear and hub has resolved that issue, plus also helps with keeping the gear true on rotational axis.

ive been flying them for quite some time with 0 issues now...

Thank you for the clarification Matt . On a side note , when using the optional full style crown gear , do you still recommend installing both washers between the main gear and the crown gear like you indicated earlier ?

[mdhelicopters]

Originally Posted by FREESTYLER_LB

Thank you for the clarification Matt . On a side note , when using the optional full style crown gear , do you still recommend installing both washers between the main gear and the crown gear like you indicated earlier ?

Yes, regardless if using the existing style crown gear hub or the optional new style, I would suggest to run both washers between the main gear and crown gear.

[FREESTYLER_LB]

Originally Posted by mdhelicopters

Yes, regardless if using the existing style crown gear hub or the optional new style, I would suggest to run both washers between the main gear and crown gear.

That sounds good , I'll do just that . Thank you for following up !