QUESTION
How to go about fine tuning a Wave Table?
ANSWER
These (below) suggestions are aimed at tuning an M8 WT…..the next model size up from the M5.
However, they should hold good for the M5.
I cannot over state the importance of having a small “dummy” sample on hand.
This is about 1 to 2 grams minimum of fine gold particles, mixed in with a half cupful of blonde sea sand….that has been screened finer than 1mm (ie all goes through a mosquito mesh size screen).
When you first set your M5 up, try running the dummy sample over a number of times to ensure that you have a roughly good set up. That is your water sprays, bump action, counter weight (only if deck is fully loaded up) and tilt are ok.
Regards,
Ian
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BUMP TABLE:
I am keen to have you running your Wave Table well….so here’s a few hints….
General points:
* The waves should form if the speed is around 287 to 320 RPM …or strokes per minute. (In case of M5….run at 12.5 Volts for most feeds…..but maybe try 11 Volts supply for any feeds with larger gold .)
* If not…then check rpm of driven pulley with a tachometer.
* You may have a “brown out” giving slower motor speed.
* Bump should be a pronounced “bang” and approx stroke length of 10mm.
* To get going….try to have a classified (screened to say, minus one mm…20 mesh) dummy sample of sand and gold ….and adjust the table tilt so that the back legs are initially about 80mm high….so that the gold cons remain in a line across the deck….about half way between cons water spray bar and the feed hopper….which is about 100mm to 150mm below the cons collection trough. Once you achieve this ….then slowly lower the legs by about 13mm ( ½ inch ) at a time…to bring the gold cons into the collection trough/launder. Do not over feed M8 to begin with. Always, keep this dummy sample to test run the M8.
* Whenever the M8 is stopped…. When started again….you have to ‘fluff up’ the table material….to stop packing down.
* Make sure the back leg adjusters have the deck ‘ level’ across ways…using a spirit level.
Your Wave Table will operate optimally by:
* Having the WT firmly bolted down, preferably to a concrete slab
* Having it transversely level
* Having motor running at correct speed….4 to 5 bumps per second
* Having the high end at correct tilt for the feed (better to have tilt steeper, then gradually lower down)
* You can have 20 liters (5 gallons) a minute of wash water in the feed box ok. But you do not have to have much coming out of the cons spray bar. Sometimes only a trickle is required from the cons spray bar…play with this a bit. A strong cons spray flow, will tend to wash gold (heavies) down slope more. This can be used to advantage, sometimes….eg in cons clean ups.
* Also you may have to drill an extra spray outlet hole at each end of the cons spray bar….so that spray water goes right to the edge of the deck. Just drill a 3/32 inch or 1/8 th extra hole at each end.
* Having the water sprays from cons spray bar, slightly aiming down the deck (not just aimed directly, into the trough) can be an advantage.
* Having correct 'bump' adjustment…and lock it so that it does not move through vibration.
* If WT bump plays up….while running, wind in clockwise the bump adjustment bolt until WT almost stops bumping…then wind out anti-clockwise to the correct bump. If you have bump too far anti-clockwise…the WT will stop bumping. So that is when you wind it in…then back it out again.
* CLASSIFYING your feed is very important….no oversize trash should be competing against your finer gold particles. Also, the feed hopper discharge holes may clog up.
* Do not over-feed the Wave Table…to begin with
* Try to feed steadily…reduce surges in the feed
* To begin….try to have the Cons line about 100mm (4inches) down from the cons trough. Always achieve this prior to lowering tilt to produce a continuous cons discharge.
* Tighten up all grub screws as some come loose in transit
* For M8s…Screw in Grease Nipples in each linear bearing and grease each 12 hours of running (for M5s I will find out the greasing system)
* Just a few quick points above to try to help. Try not to change too many adjustments at the same time. Let WT settle down to an equilibrium ….a minute at least between adjustments ….as it takes time for WT to settle.
* Note that after each time the WT is stopped….one has to “fluff up” the deck residue….particularly run your ring finger under and along the leading edge of the nylon riffle bar….to ensure NO PACKING of feed pushed up against riffle bar. As gold will shoot over top of riffle bar…instead of having to go under.
* If you have a poor run….then, simply re-run the tails back over the WT until you get it right. This is great for test work and clean-ups.
* You should have plastic tubes/hoses coming off the tails and the cons outlets. Best to run cons into catch buckets. I use a small bucket inside a larger bucket, inside an outer bucket for the cons. The largest of the 3 buckets has a water over flow hose at its top. The cons delivery tube protrudes down into the top area of the smallest bucket.
* Empty cons bucket regularly, so that delivery tube does not fill up.
* Tails can go out many ways….I often use a length of open steel /gal guttering/PVC pipe… to take tails away sideways from the WT…on a 10 degree minimum slope. For test work I use a catch bucket on the end of the tails discharge so that I can sample/assay the tails etc.
* For fine gold in your feed, consider dripping into the feed hopper some detergent to break down the surface tension and reduce likelihood of 'float gold'.
* When feeding some sticky materials or old tailings…consider using a small scrubber/trommel to pre-condition your feed material to the Wave Table. It will ensure the full 'wetting' of your feed and also it will remove any oversize or trash.
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