Rocker box/cradle - fixed or sliding hopper?

[RedDirtDan]

Hey all - I'm going to build another rocker box, this time bigger than my last one (had an approx. 8x8" top hopper and 9-10" wide run).

So I've started to do all the obligatory searches again, Youtube, on this site, and I've noticed that most now seem to have fixed in place top hoppers, so all the action needs to happen on the classifier screen, rather than a sliding hopper to get that slapping agitation. And well... others look like they are trying to build a rocker "sluice" - i.e. designing very open screens with large bilge pumps so that that rocking action is basically just to feed water - which it probably a thing if you live in a "no highbanker", but yes to rocker box location.

What are people's thoughts on this? I know the guys I go fossicking with finding the knock, knock, knock after about an hour to get on their nerves - usually I hear the call of "can't that thing play any other tunes?!?", but I thought the sliding hopper was part of the key design, but on second thoughts, maybe not so much.

The plan at the moment is a 12x12" hopper or bigger. I run a drilled plate with 6-7mm holes on a 1" spacing - this gives good working time vs an open classifier which just has everything falling through, but everyone seems to run open mesh classifiers.

Dan.

 

[RedDirtDan]

One time I was mucking around and did a drawing/render of a Rockin' Rocker Box - rip the wheels off and rock!

 

[RedDirtDan]

Long time original post, but in the end I just made an aluminium rocker box. Still some bits to evolve on it, but that's the fun! I did make another wooden one, so I guess I have more rockers than arms now!

 

[Mackka]

Looks great and wondering thedifference in weight between them. Cheers Mackka

 

[sand surfer]

the aluminium box looks the goods RDD

a old mate not with us any more

with his rocker box he had a 1/4" piece of wood nailed to both sides of his screen punched with 1/4' holes

me asking what i thought at the time a stupid question about why the 1/4" wood rail on both sides of the classifier tray

his more than logical answer was clay ,heavier clay needed more time in the sliding rocker box
hence turn the punched holes facing up and there you had a aggressive classifier

so to answer your question to have or not to have a sliding rocker box will be with your decision

 

[Mackka]

Makes sense SS just like a cheese grater to cut the clay up.

 

[sand surfer]

yes mackka and the 3mm to 5mm extrusion when you punched the tin plate by yourself

he was a very wise man when it came to prospecting mackka
i am sorry i did not get to spend more than 10 years with him before the great golden path we all must follow took him (at 95 )

i have a short fuse mackka and he had a looooooooong one
and him being a stickler for the rule of thumb

we had our moments but after a quite walk by myself
i came to the conclusion that he is not as dumb as he makes out or pretends to look

( i can still see some of those stupid facial expressions he used to pull when we had a difference of opinion and i would walk back into camp )
but we had some never to be repeated times around the camp fire and in the creeks and flats
rip old mate

 

[Midmountains]

Long time original post, but in the end I just made an aluminium rocker box. Still some bits to evolve on it, but that's the fun! I did make another wooden one, so I guess I have more rockers than arms now!

What matting did you use?

 

[RedDirtDan]

What matting did you use?

Just backed miners moss and aluminium expanded mesh - catches lots of fine stuff!