mod .?

[anthony1]

could someone explain the mod .? reference , I think its to do with pinion and main gears but not sure whats what, the reason I ask is I bought a 480 extreme from a helifreak member , he mentioned something about mod .5 being better for a stock setup but it also has a mod .7 , to me that sounds like gibberish but It must be important . so therefore the question
thank you
Anthony

[Crashalotjoe]

The mod (or module) is effectively the size of the teeth on the gear/pinion. If a mod 1 gear has 1mm teeth and there are 200 teeth then the circumference of the gear will be 200mm. The same 200 tooth gear in Mod 0.5 will have a circumference of 100mm (i.e. each tooth is half the size.

The smaller heli's (400/480/550) have either 0.5 mod or 0.7 mod gears as standard, the larger ones go up to Mod 1.0.

Mod 1.0 gears are stronger than the 0.5 or 0.7 so it is not uncommon to 'upgrade' the mid-size heli's from 0.7 to 1.0. My 550SX has the original 0.7 gearing changed to 1.0 gears.

[Mentalic]

Mod is short for modulus a standard way of describing gear teeth. All you need to know is the higher numbers are larger stronger teeth, Mikado has .5,.7 and 1 modulus gears.
I run the Mod .7 gear on my 480, finding the right sized pinions for your motor can be a problem when changing stock gears. But you can and its one of the fun things about Mikado helis.

[GimpyGolden]

Mod is referring to gear pitch.
The Mod .5 is stock gear for 400/480. Has the smallest tooth spacing and the smoothest running but may not hold up as well to heavy loads or big motor.

Mod .7 is stock gear for L500/550. Can put up with higher loads, maybe a little more noise. You need these if you want to use a motor with 6mm shaft as only these and M1 offer 6mm pinions.

Mod 1.0 600/690 stock gears. Handle greatest power, no need on 480.

Also note each Mod choice offers it's own range or gear ratios.

[smittylube]

I stretched my 480 to run 523's and have no problems with the stock combo motor, main and pinion, but I don't fly super hard.
I prefer how quiet it runs and the herringbone design makes even the lighter version stronger than straight cut gears.
With any setup/mod - mesh or lash is king in how quiet and how well it holds up to abuse, and also alignment of pinion to main gear.

One last thing to think about is how fast it spools up- have read some flying 5.3 pro then switching to v 6 with Vcontrol and having issues most likely due to a faster or instant esc motor response than previous versions.

[anthony1]

thank you all for the info, that's a lot to digest , so I guess its important to know which mod I have

[cudaboy_71]

Yep. Just think of it as a relationship between three values, much like ohms law.

Module = reference diameter/ teeth

With basic algebra you can solve for any unknown given the other two.

The main takeaway is you can't mix module in the same gear train. They won't mesh properly and you'll have a mess of stripped gears if you try.

[jhamel]

In general, higher MOD yields stronger gears, but may create more noise. 450 size helis tend to use around 0.5 MOD gears, 550 size helis 0.7 to 1.0 MOD, and larger helicopters tend to use 1.0 MOD. The largest MOD size gears I've seen in the hobby are the Synergy 1.25 MOD TT gears.

When meshing gears, you need equal MOD and equal teeth angles. Mikado produces more than one version of the pinion and main gear tooth angles for the same MOD size, so make sure you don't mix and match when ordering spare parts.