1/10 scale to 1/8 scale

[tuna.Rc]

I have a really stupid question. I've searched the internet and came up with nothing. Probably because I myself don't even know how to ask what I want to ask.

Is there a " formula " or something used when figuring dimensions on a resized part ?

I basically want to build a 1/8 scale Tamiya Hornet, using a 3d printer. I have no idea on what size any parts need to be or how to figure it out.

[Dadio]

Original part size multiplied by ten then divided by eight should do it . if you want to use 1/8 standard wheels then you will want to use a standard 1/8th hex drive ( don't know what that is ) not the Tamiya style drive flange , if your modeling up replica wheels then again adapt the size to fit a stock tire for 1/8th unless again you want to print tires as well .

[Coelacanth]

if you want to use 1/8 standard wheels then you will want to use a standard 1/8th hex drive ( don't know what that is ) not the Tamiya style drive flange

I believe the answer to that question would be either 14mm hex or 17mm, with 17mm being far more common.