Metal Hobi MH-245 kit as Hitachi ZX245 excavator

[Blender]

Decals are looking pretty nice. They are dry transfer style so there is no carrier layer left behind. The ink is directly backed with an adhesive. As good as a pad print without the need to create any tooling. Had to learn Inkscape software to make vector images. It's free. A bit different than Photoshop or CAD, but I managed to bump my way through it. May have put the model number on crooked.


Included slew motor is a 37mm OD gearbox ~150:1 with an 1806 brushless motor. It worked just fine, but was too loud for my liking. Grease helped, but not all the way since it's an 8-10 stage unit. From my reference photos it's just about the right size to be scale though. Gear mesh for the slew is not adjustable and had a little bit of free play at the bucket <4mm at full reach. Not bad, but I can't leave things alone. I used this opportunity to make an adjustable motor mount for the stock 37mm OD gearbox shown below on the left. I also made a plate for a smaller 22mm OD planetary gearbox (right). Adjustment is done blindly before final installation, so it's fumbly and takes some trial and error.



I installed a 22mm 104:1 planetary gearbox on the new adjustable mount with an oversized outrunner. I was able to tighten up the gearmesh to allow only 2mm play in the slew at full reach. I think I can get it a little tighter when I swap out the used 22mm gearbox with an improved unit. The shaft of this one has some radial play from being old and beat. The new 231:1 22mm gearbox has a much tighter shaft. I still need to turn down the tip of an appropriate sized outrunner before final assembly.