700 Mod 1 gear from MicroHeli

[Stuart]

Okay I'll throw a theory into why some will see it.

1. Every heli out the box will be within a certain % identical. (that's where it stops)
2. Every pilot will run different servo's with the capability to drive the cyclic very hard in any position under high load.
3. Not all pilots have the skill to manage pitch and loading in harmony - most are good but its a different league to get it perfect.
4. Every helis will have different blades / paddles and this again hits the loading

When I'm saying loading we are also getting into stress loading on the frames.

The Align 700 places the rotational loading of the head into the top half of the frame with the main gearing suspended below it. Then add into this that the heaviest part of the heli .i.e the engine sits below this, so you have a spinning load inducing element above the main gear and a lump of metal getting thrown around below with a muffler attached.

The bit in the center is critcal to ensuring that all stays true.

So you have the main gear at the very end of a shaft that any slightest flex with be amplified by the time it reaches the end of the shaft where the gear sits.

Now if you make the shaft longer and drop in a third block this should.

1. Pass the load across the whole frame not just the top
2. Keep the main gear in place

The added problem with the current problem is that the gear will put pressure on the pinion and into the engine main shaft and I bet some are seeing thier plastic pinion blocks over time will be able to move also.

I'm sure there is loads more to add into this, but this is why I believe even with mod 1 this will not resolve it. Plus it could potentially make it worse for the engine shaft with more pressure on the pinion as a result.

[Smoothound]

Not convinced here. The gear is far too skinny...period. It's possible the frame flexes to a degree but the fact the gear is well undersize is and has no way of adjusting is far more important. If it still happens with the mod 1 gears(I doubt it) then the best way is probably a thicker frameset with stiffeners maybe, buggering around with drilling, feeding a shaft inside the mainshaft etc. is mental to the nth degree. A better option would be sending all the 700's back to Mr Align and telling him where to stick them

[kamikaze]

Very valid theory but I run V-blades,451's on 6v and my collective management is about as good as RBS bank and I have yet to strip a gear. I'm not arguing I'm just amazed that I've not and to be honest there are about another half a dozen 700's at the field and I only know of two stripped gears one of which was a pre-production kit. Strange init would make a good X-file.

[robgt]

I just realised I have a "case in point"

On my Trex600, which DOES have a bearing block below the main gears (3rd bearing block) - Using the standard plastic bearing blocks with metal cross member pins in them, I have had to replace those metal pins on two occasions due to them being bent (understatement). This is only in the bottom (3rd) bearing block...

I also tend to find that the bottom bearing is the first bearing to need replacing from going notchy because of the hammering it gets on a 3D heli.

As Stuart has said, the smallest amount of movement is amplified by the time it reaches the end of the main shaft, which on the Trex 600, sits inside that bottom bearing.

I don't know why the helicopter was designed without that 3rd bearing block - the 600 has it, why wouldn't a 90 need or benefit from it?

Cheers,
Rob

[kamikaze]

If only Align were as good at customer relations as Optifuel or Spartan we could all inundate them with emails. I'm 100 % sure that they know what the problem is and it's fix but don't want to admit it.

[t-rex pedro]

Stronger sideframes seems like a great idea. I've worn out the sideframes on a Trex600 (and so has a mate of mine) to the point that they were flexing badly in flight causing all sorts of issues.

The Align MOD 1 gear is available at Midlands, by the way. With staff off sick and everything being extremely busy, the website hasn't been updated as much as it usually is.
Cheers,
Rob

You must hammer that 600 Rob! Sheesh!!!

Is the Align gear MOD 1 or is it the -1 part?

[Stuart]

Not convinced here. The gear is far too skinny...period. It's possible the frame flexes to a degree but the fact the gear is well undersize is and has no way of adjusting is far more important. If it still happens with the mod 1 gears(I doubt it) then the best way is probably a thicker frameset with stiffeners maybe, buggering around with drilling, feeding a shaft inside the mainshaft etc. is mental to the nth degree. A better option would be sending all the 700's back to Mr Align and telling him where to stick them

Phil your right that also to help the loading if you increased in effect the surface area of the teeth this would also help the best way to do this would be to use helical gears that can take loads far better than std gears, but the knock on effect is also more contact = more drag but in the scheme of things a helical option would be expensive also.

[raptorheli2]

to clarify, align do NOT make a mod 1 gear. the gear they offer is a bigger dia only.

cheers

[Stuart]

Also as mentioned another factor will be the ambient temp's. you will be surprised how much more flex will hit into this as we get warmer. Remember the links issue didn't really surface till the cold came and the plastic started to get brittle.

[t-rex pedro]

to clarify, align do NOT make a mod 1 gear. the gear they offer is a bigger dia only.

cheers

Thanks, thats what I thought.

[Tom Burgess]

So has anyone tried one of these MOD1's yet? Over on the freak I am hearing reports of the Microheli MOD1 still having lots of flex.

I got my microheli mod1 gear set today. At first look I'm not very enthusiastic about it. May be regretting going with them again after the INSTA strip

• teeth on the main gear are cut to a fine point
• the teeth on the pinion are cut to a flat point
• the new delrin main gear still has about the same flexibility as the old stock gear

I pulled out a spare MA gear I have and the difference in the cut of the teeth is quite a substantial. The new pinion meshes very smooth on the MA gear but is very notchy/grabby on the microheli gear...well at least as testing by hand on the bench and not mounted.

I got through a gallon yesterday and today on the third bearing mod with an original pre -1 gear. I was timid at first but by the last flight started feeling confident to toss it around harder. So, I'm going to let this mod 1 gear sit for awhile until I get more time on the third bearing setup. I can notice as well as the guys I was flying with is that my 700 sounds a lot different now with the third block. Much more solid if thats the way to describe it. I've also noticed a difference in spool up vibs. I used to always have a low frequency vib in the tail and some large bubbling in the tank while getting up to speed. Now their is now visible vib in the tail but my tank foams something fierce! Visually my 700 is vibration free now except for the tank. Something is going on ??? The third block has definitely tighten up my 700 but is also may not be a true as I figured on the bench. Maybe trading on source of vibrations for another. But overall it does feel like an improvement in the air and the sound is much more tight/solid if not more quite.

This was stmpngrnd's findings. He did a build thread of electricsceadu's 3rd bearing mod aswel.

[robgt]

to clarify, align do NOT make a mod 1 gear. the gear they offer is a bigger dia only.

Apologies... I got my Mod 1 and my Dash 1 mixed up!!
Doh!

Cheers,
Rob

[Sao]

I think I'll wait for Miros mod1 gear conversion. Pretty sure that will be a full main gear with no holes and hence less likely to wobble.

[Tom Burgess]

I think I'll wait for Miros mod1 gear conversion. Pretty sure that will be a full main gear with no holes and hence less likely to wobbel.

That is my thinking too on this.

[Sao]

I hope he also makes a third main bearing block, perhaps he should just make a whole new heli