Post by connrock on Nov 5, 2013 8:58:02 GMT -5
Andria,
Through the years I've found that measuring the amount grit needed for any given load by volume doesn't always work out unless you accurately weigh the rocks.
A 6 lb barrel may or may not have 6 lbs of rocks in it,,,it may have more or it may have less then 6 lbs of rocks.
I am fortunate enough to have a VERY accurate deli scale and weigh my rocks which tells me exactly how much grit to use for any given load.
I've found that 10 lbs of rocks needs 1 lb of rough grit so I weigh my rocks and add the right amount of grit,,,,by weight not volume(tablespoons).
I just went in a weighed 1 tablespoon of 60/90 grit and it weighed 0.007 lbs.
That comes out pretty close what I use,,,0.006 lbs of 60/90 grit.
The KEY hear is knowing the exact weight of the rocks and not assuming that a 6 lb barrel always holds 6 lbs of rocks.
Hard to guess here but I would say the reason you had grit left over was due to the plastic pellets and (maybe) too much rough grit.
Too much rough grit:
A little over a month ago I started teaching a woman how to tumble rocks at my home.
The first week she came here my deli scale was out of order so we used Lortones formula for rough grit which was 10 tablespoons of rough grit for 6 lbs of rocks.When she started loading the grit into the barrel I said to her,,,'Wow,,,that looks like an awful lot of grit".
The following week she came again and when we opened the 6lb barrel there was a lot of grit in there.
We cut back to 7 tablespoons of rough grit and found the same thing the following week.
I now had my deli scale up and running so we weighed the rocks and grit that week and she commented on how much less grit we actually needed!
What I'm saying is that it's almost impossible,, for a person just learning how to tumble,,, to judge how much grit you need in any size barrel if you don't know how much the rocks weigh.
In time you'll be able to guesstimate how much grit to use without trying to do things so accurately but in the beginning there are sooooooo many tings that can,, and will go wrong that the more accurate you are the more you can nail down what you're doing wrong.
Keeping a log of what you're doing is a VERY good idea.
In time you'll look at that log and laugh! LOL
connrock
Through the years I've found that measuring the amount grit needed for any given load by volume doesn't always work out unless you accurately weigh the rocks.
A 6 lb barrel may or may not have 6 lbs of rocks in it,,,it may have more or it may have less then 6 lbs of rocks.
I am fortunate enough to have a VERY accurate deli scale and weigh my rocks which tells me exactly how much grit to use for any given load.
I've found that 10 lbs of rocks needs 1 lb of rough grit so I weigh my rocks and add the right amount of grit,,,,by weight not volume(tablespoons).
I just went in a weighed 1 tablespoon of 60/90 grit and it weighed 0.007 lbs.
That comes out pretty close what I use,,,0.006 lbs of 60/90 grit.
The KEY hear is knowing the exact weight of the rocks and not assuming that a 6 lb barrel always holds 6 lbs of rocks.
Hard to guess here but I would say the reason you had grit left over was due to the plastic pellets and (maybe) too much rough grit.
Too much rough grit:
A little over a month ago I started teaching a woman how to tumble rocks at my home.
The first week she came here my deli scale was out of order so we used Lortones formula for rough grit which was 10 tablespoons of rough grit for 6 lbs of rocks.When she started loading the grit into the barrel I said to her,,,'Wow,,,that looks like an awful lot of grit".
The following week she came again and when we opened the 6lb barrel there was a lot of grit in there.
We cut back to 7 tablespoons of rough grit and found the same thing the following week.
I now had my deli scale up and running so we weighed the rocks and grit that week and she commented on how much less grit we actually needed!
What I'm saying is that it's almost impossible,, for a person just learning how to tumble,,, to judge how much grit you need in any size barrel if you don't know how much the rocks weigh.
In time you'll be able to guesstimate how much grit to use without trying to do things so accurately but in the beginning there are sooooooo many tings that can,, and will go wrong that the more accurate you are the more you can nail down what you're doing wrong.
Keeping a log of what you're doing is a VERY good idea.
In time you'll look at that log and laugh! LOL
connrock