Quick build 'Blue Bowl'

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Mar 5, 2013
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As promised, here's how to wack together a copy of a 'Blue Bowl'.
For under $12!!

Bunnings was my prospector supplies store today!
A bowl, $4.50, funnel $1.98, three way hose adaptor $5.50.


The bowl is quite big, and comes in differant colours, I chose 'Garrett Green' ;)


The first thing to do is block up one of the holes in the three way fitting with silastic. (note the adapter I bought has one inch fitting, this is not necessary, it was just 50c cheaper than the three way half inch one!!)


Then whilst thats drying, cut the bottom out of the bowl with a grinder.


Then cut the spout off the funnel, to give about a 3 inch hole.


Now centre the funnell and glue to the bucket.


Now you will need a hole saw to cut a 20mm hole in the bowl, about 25mm from the base.


OK, now glue the three way fitting in place, with the blocked hole on the inside!! Slightly angle the open hole, downwards.
note here, I stuffed up and was a little rough on the bowl, and cracked it. I have since had a look at my one I built ages ago and the plastic is much stronger than this bowl, even though they are the same. Anyway, it wont affect operation, so I just glued it up.


Now get some silastic around the join of the funnel and bowl from the underside.


Let the silastic go off and test!!


There are plenty of vids on u-toob to show you how to use one, but what I do is put the hose on and fill so the water is just overflowing.
Turn water off, add detergent, add cons, turn water on slowly.
The fines should just start to move.
Turn water up unti you have a definate swirl happening, you will begin to see a fine spiral line of black sand going up the side of the funnel and out.
The fines in the bottom of the bowl will start to form a star shape around the funnel.
I then turn up the water quite high, but not as high to let the water go over the sides of the bowl.
After maybe 5 or 10 minutes, your front lawn will be satisfactorily watered, and you will have just gold, and fine gold too, left in the bowl.
Turn water off, remove hose, and pour into a pan...simple eh?
Sadly not my invention, but they do work remarkably well.
So well in fact that at the mine I dont even bother trying to seperate all the black sand at clean up.
I do the best I can, then simply pour the rest in the poverty pot, to go in the blue bowl when I get back.
What a beauty .. You never cease to amaze me good ol' Palmer neighbour mate! .. OK, now that one is out of the way, how about getting to work on an under $49 Knudsen Bowl for me to go under the trommel .............
Palmer Digger said:
What a beauty .. You never cease to amaze me good ol' Palmer neighbour mate! .. OK, now that one is out of the way, how about getting to work on an under $49 Knudsen Bowl for me to go under the trommel .............

Got one of them here....I started on it, but its a rainy day project!!!!
Yep, I was very impressed, I have a pile of so called "panned within an inch of its gold" dirt out the back, no prizes for guessing where that is going!! ;)

Thanks again GM.
Absolutely mate,
I have done that before.
I just rather use a hose and mains water coz I can down in Cairns!!!!

But dont forget, this is a finishing tool, and on a delicate scale. It will handle fines and thats it!
It wont lift little bits of quartz the size of a pinhead...

However, as Tone commented today, this thing works in a similar manner to other centrifical processors.
I do have a knudsen type machine in bits here, that you could well put at the end of a small 'commercial' operation. It operates in a very similar manner.
What a beauty GM! Thanks kindly for the post!
Gotta love home engineering when it works as good as (or sometimes better than) the baseline product! Very nicely done.
I'll bet you could nearly pull this build off for little to no cost. Got me keen to head out to the shed for a rummage.

Just wondering if a smaller scale model could run effectively? During our trip in May I might even bring home a small bag of cons, throw one together and see if I can get it to run well.

Boy, that 44grams in the pan looks the business! Just stunning :D
Cheers Shauno,
Bud I see no worries in down scaling, or for that matter up-scaling this piece.
I have not tried, but dont see an issue. Shit, those bits were 12 bucks! I reckon a smaller version could be done for less than $10!!

Hang on...... there's a challenge!!!.....

I'll try and find a photo Shauno of a clean up we did earlier this year, wasn't the best in history, but our best...I'll see if I can dig it up!
I might take you up that challenge soon ;) Blue bowl under ten bucks, any size (over say, 8" should be enough). Easy enough to run from mains water. Might throw a spanner in the works if a small 12v pump needs to be purchased for recirculating. I'll see what I can find cheap though!

Looking forward to seeing that photo mate. I'll get the drool guard positioned over the keyboard!

Well done and on the cheap too.
I was lucky that I was given one of the original BB's but I was not that impressed with it so the chooks had a new water bowl for a while.
But after checking out one of the mates BB & realised I was using it the wrong way.
So to the dissapointment of the chickens I reclaimed it from the chook house and got it blasted.
It works well on the fines.

Stolen from the chooks

Sand Blasted and ready to go.

A bit of fine gold from the cons kept.
Thanks Brad and all.
Gotta think of the next 'cheap as chips' thing I've built over the years to show ya's all!!!
I showed tenouncetone the baby shaker I built, or bits of it....but that was about a grand to put together...
Hmm the petrol vacuum is a candidate, it was basically the price of the leaf blower, so maybe a couple of hundred??
I'm rakkin' me pickled brain to think of cheap stuff to build???
Shauno's hand dredge is a killer, thats good....
I dunno.....?? 8) 8) :rolleyes:

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