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Multi Purpose Rotary Machine - Mulling, Welding, Pottery, Photography Turntable

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Step 45: Green Sand Muller - Problems and Solutions

Picture of Green Sand Muller - Problems and Solutions
green sand prob res1.jpg
green sand prob res sand.jpg

In general this is working great. There are a few little problems that needed/still need attention:

1. I found that only one of the two wheels was doing much, the other was not rotating. After stiffing up the pivot/mount (see note) of the pipe that holds the wheels, they were held more square to the platter and now both rotate. Solved

2. When I added water to the green sand, clumps of it would stick to the crushing wheels (you can see this is the video linked to in the last step). Not really a big problem, as you can just brush it off at the end, but that all adds time to a process that I want automated. To fix this I wrapped the face of the wheel in a slick plastic repair tape. Solved

3. The Wheels squeaked too much... Greased the pipe shaft - should have done this from the off, but was just testing the principal of the contraption.Solved

4. In greasing the shaft I made an excellent adhesive for fine particles of sand. I see this happening already, and if left unchecked this will quickly wear the shaft wheel interface. I should therefore add a rubber seal of some kind. Yet to do...

5. The outermost plough blade periodically scrape on the side of the basin. Functionally this is fine, but it makes a noise much like a hyperactive cockerel riding in a poorly maintained wheelbarrow... I thought I had fixed this by slight adjustment, but after re-filling with sand, it turns out that the added force of the sand on the blade, pushes a smidgen more towards the outer edge and it still scrapes.... Still need to sort this...

Apart from that this is working great - well please :D