ah64

Is shimming the gear boxes that important? I was looking at some forums but I dont see how shimming the gears so that they stay inline with one another is really a benefit. If you were pulling alot of weight then I could see how the gears would be stripped if not inline since all the force would concentrate on a small area of teeth, but is it really worth it? Just a curious Question. If so how would you go about doing it? Nylon or metal shims?

martin g

I havent done this, but like you I have read a great deal about it and other mods and questioned thier worth. By profession, these days I am a Mechanical Engineer and I deal with gearboxes and thier failures etc daily on a proffessional level by coincidence. So, from my humble experience on the face of things you are right, meshing the gears correctly is important for industrial uses where torque loadings are high etc, this way you get all the force spread evenly accross the gear wheels. Whether it makes a difference or not on a 1/16 scale model is a different matter. If the gears are only meshing say accross a third of the width, then yes its too close for comfort and there is a chance that they could strip. If they are pretty much in line, providing you dont overload the gears you shouldnt have much of a problem. The main thought from me is the axial movement the gears have, not so much the alignment, they travel along the shaft a lot ( couple mm is a lot of travel when your spinning at 200 rpm) and this will cause 'uneven' wear to the INSIDE of the wheel and that could lead to problems.

So I guess it comes down to how you are going to use the model, if your going to add weight ( metal wheels and tracks etc) and then climb rough and heavy terrain it would help of course as the demand on the gear wheels will be higher than 'design'. Now, thats the crucial word here 'design' with anything if you choose to exceed design use you should always consider the impact on the unit and modify accordingly. So..if your going to zoom around the living room all day, it should be fine, there will always be exceptions of course, thats life.

The problem is that modellers by nature like to modify and enhance thier models, often for nno need other than fun, this is the enquisitve part of the brain kicking in, wanting to take things further, which to me is great because as a planet we are losing a lot of general technical thinking in the home as most things are done for us.

So, dont worry if your invading the kitchen, but if you going to mount a frontal assualt on the rock garden, consider shimming the gears I would say.

ah64

Thanks Martin g. I figured it would be more of a desire than a require.