man what a great thread, these are the type of threads i used to lose hours on, great to see the PA support is still strong. (i dont get much time to log in these days)
awesome advice been posted all points are spot on, I can tell you i own and have extensively run all the mckirk range, the letrap and no brainer... dream mat.
for me every sluice has an advantage and disadvantage, letrap is great for sand mining, its amazing at concentrating loads of black sands and gold but not very good at concentrating and final cleanup as in you go home with a bucket of black sand and does require alot of water, far more water than an 8 inch dream mat sluice. I ended up modifying my letrap with a metal frame because it would load up with heavies and warp when i was trying to clean out as its very thin. I still love it and tell everyone in my opinion its the best thrermoform plastic sluice on the market.
the MacKirk well you can look back through my threads going back to 2014 i had a ball with these sluices but in the end for Ballarat ironstone it did need allot of water and needed to be cleaned out regularly which is fine it just meant i took alot of buckets of concentrates home with me which is great for wet days but i would end up with 40+ buckets in my backyard never getting time to pan them all, i was running the au boss which is very big, the little sampler was mint for finding paystreaks before you bring the production sluice in i cant fault it either. in fact i did modify mine to take a 3700 gph bilge pump you can see the header on it here they both have a place on my wall in the warehouse.
with regard to the 6 inch mini its not meant to replace a production sluice its really the back seat sluice nice and small, efficient and fast to cleanout. I do have options for this sluice in the pipeline as with all of my products the idea is to continue to develop and accommodate customer request over time.
i'll touch on water a bit, as has been said above we are using SG to sort gold by passing it into a vortex and closing the vortex out which tears the light from heavy in an extreme controlled way, yes we need water to do that but what's more important is the water over the cells is the "Cleaning" function so less water means less cleaning, less cleaning means slower processing time which means slower feed rates.
to clarify further if you classified down to 50mesh you could easily concentrate with a trickle of water the vortex will do the work but you will hold the majority of the material still in the sluice, so the optimal situation is fully submersed particle separation why because we know gold is heavier in water outside of that we need ot use some other tricks. these are old and tested drop riffles, fluid beds etc. and they rely on the crash theory and knowing when is a good time to clean out. dream mat will self clean so you can walk away for 20 minutes with your sluice in the water and be confident your gold wont wash away.
hope i've contributed in some way, great thread guys hope you are all seeing water in your creeks this winter shes been a bit dry lately
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