G'day From Australia

[Redz]

I guess beauty is in the eye of the beholder. I don't pretend to be a welder.  My set up is impact mill on top of roller mill so I have consistent size with one pass. I have jaw crusher for breaking down to size for the impact mill. With this I have never had to change chains. Still has metal in crush, but much less as hardfaced. I made it some time ago so also hardfaced near removable disharge plate where it was wearing.

[jasong]

Is the impact mill not leaving a fairly consistent 150-200 mesh powder when you use a plate instead of just the chains? Just curious why the roller mill is necessary at the output.

Mine basically leaves all the ore (except the gold/native copper/other malleable metals) as a consistent flour. I bought some AR500 plate (roughly same hardness as hardfaced welding) to put on the chain ends, but now I'm wondering if that is going to result in a chunkier output that needs further processing?

[Redz]

The plates dont create a chunkier output. It is the same if not more consistent than when I tried a chain, since that is mostly controlled by discharge plate.

The reason for the roller mill is two fold. 1. It allows higher rate of throughput through the system, as you are not constrained by output size in the impact mill as much for fine grades i.e. you can have slightly larger slits in discharge plate yet get finer more consistent output faster. 2. The roller mill allows you to control output size very consistently since it is adjustable, and you can get a much finer grade of output. But it is really consistency, as there is much less variation in the distribution of output size if you are going to table it.

These only really matter if you are processing more than a couple of rocks in a test sample

[Redz]

I have also switched to AR600 for building picks and these applications. Endurasteel is also good

[jasong]

My concern with the AR plate in the mill was brittleness, wasn't sure if it'd be better to go with AR or hardfacing in applications like that, though I guess hardfacing is probably more brittle than mild steel too.

Any reason to tie both chains together with a single plate vs go with 1 plate per chain end? Mine has 4 chains inside like yours. 

I need to cut up some of this AR500 and just give it a try. I constantly wish someone would build a better Hermit pick here out of AR instead of the shovel material that basically lasts 1 season. 

[Redz]

This is my AR600 one. I used to use 400 but wanted more durability

[davsgold]

5 hours ago, Redz said:

I have also switched to AR600 for building picks and these applications. Endurasteel is also good

I also make picks, these are quite popular and the main one is the medium size with a 700mm long Spotted Gum handle which is similar to what you guys call Hickory

5mm boron steel plough disc blade and 8mm boron steel plough disc point, pipe collar oval shaped to fit the oval shape handle

The Boron steel in the plough discs is similar strength and wear resistance to the AR600 steel that your using, the shape of the plough disc is the finished shape I like so the parts are just cut using a plasma cutter which does not over that the material

 

[davsgold]

5 hours ago, Redz said:

The plates dont create a chunkier output. It is the same if not more consistent than when I tried a chain, since that is mostly controlled by discharge plate.

The reason for the roller mill is two fold. 1. It allows higher rate of throughput through the system, as you are not constrained by output size in the impact mill as much for fine grades i.e. you can have slightly larger slits in discharge plate yet get finer more consistent output faster. 2. The roller mill allows you to control output size very consistently since it is adjustable, and you can get a much finer grade of output. But it is really consistency, as there is much less variation in the distribution of output size if you are going to table it.

These only really matter if you are processing more than a couple of rocks in a test sample

thanks for putting up the pictures of you milling setup, I like the idea and also like the idea of a Jaw crusher above the impact mill and the rollers for the final processing

I know most of mine is fine flour powder but there is also some gritty bits still about the size of sugar grains, and if I can reduce the metal from wearing so much will be great

[Redz]

Your picks look good. I considered discs too. I just made for my own use. 

My jaw is separate as easier to move and load that way, but is a lot easier to get consistent 1/4 to 1/2 inch feed than a dolly. 32 kg in a dolly must not have been fun.

The sugar grains and intermediate grains are what I wanted to avoid, as they are a pain in the final stage. You can reduce them with smaller discharge, but then it slows up the process a lot. 

[davsgold]

2 hours ago, Redz said:

Your picks look good. I considered discs too. I just made for my own use. 

My jaw is separate as easier to move and load that way, but is a lot easier to get consistent 1/4 to 1/2 inch feed than a dolly. 32 kg in a dolly must not have been fun.

The sugar grains and intermediate grains are what I wanted to avoid, as they are a pain in the final stage. You can reduce them with smaller discharge, but then it slows up the process a lot. 

it's a big dolly pot and bar to break the quarts down but like you say is is very uneven in size