Post by rykk on May 5, 2014 2:53:24 GMT -5
I never had any trouble with my 20" Lortone walking. It did just fine with the rubber pads on the feet. I do, however, have to pile heavy rocks on 2 opposing sides of the rig now that I've mounted the pan on shock mounts and gone to a quasi-reciprocal motion using an offset shaft.
What is the purpose behind separating the pan into 4 sections? I'm sure there's a reason, but I can't figure out what it is. How do you keep it from impeding the rotation of the rocks around the pan? I've been thinking of how I might install a 2-4in pvc pipe in the center of the pan to try to prevent dishing of the pan - do you think it would be worth doing?
Most of the slabs I jiggle are too big to fit into a 6" circle and I've found that rubber rings around the rocks doesn't work because nodules with sharp-ish edges and a low slope tend to just work under the rings and toss them aside. So I don't do either and feel like the wood cross and rings eat up a good bit of valuable space in the pan. I've gotten up to 30 rocks into my 20" once by just taping them and don't have any problems in the grinding phases with tape coming off as long as I don't let the water/slurry get too deep. Too much water lessens the grind, anyhow. Typically I can do 20-25 at a time unless I'm doing some really big slabs or nodules for display. The only time I go to super sticky tape is when doing the second side of a slab. The polished side is really slick, so outdoor rated duct tape is a must. Plus, I tend to end up with my polish pan on the wet side from constantly spraying tin oxide off the sides of the rocks to save $$.
I never tried glue on slabs because it seeps into softer rocks, like jasper, and discolors them. Taping isn't as time consuming as it sounds - you get real good at it real fast. You do need to be careful pulling it off but it's usually pretty wet and, as long as you don't try to pull it UP off the slab, you're pretty safe. Some of the stick-um gets left behind, but that comes off easy by just taking one of the rolled up pieces of tape from the bottom of the weight and rubbing the leftovers off. Tape loves to stick to itself.
I only have one jiggler and 2 pans, so I wash out the grind pan after every batch/side. Too much grit or old grit more than 20 hours old doesn't do much of anything even if you add more new grit. The old stuff just gums it up. I only add grit once and only about 2 hours into the 60/90 grind. Just 2 or 3 tbsp. The 600 phase is the only one where you want the grit to wear down as fine as possible and might run it a long time or, better yet, repeat it.
I hear you about using the attached weights as "handles" when working the slabs on a wheel. Works great! With tape, though, I've found that there's always some fine grit dust left between the folds no matter how much you spray it off and it will pollute your polishing wheel leather/felt. Found that out the hard way.
The 4-bolt pillow blocks they use are the wrong bearing for the job. What you want is one of those 3-bolt stamped flange farm equipment bearings like came stock on the older Lortones. They are made for tough side to side stress like spinning an eccentrically weighted shaft. Found that out on my modified rig. The 4-bolt on the bottom of the pan base and also the 2-bolt one nearest my counterweight very soon developed a lot of slop. The rig was quiet as a mouse - not counting the low, hissing sound of the rocks sliding on the grit and the cooling fan for the motor - for a few days. Now, it sounds like someone idling a Harley on my back porch 24/7! Still works fine, so I'm taking my time on replacing the bearings. Not only is it a gritty job, but getting everything plumb and perpendicular was a real pita and I'm not in a hurry to be doing that again.
C-ya,
Rick
What is the purpose behind separating the pan into 4 sections? I'm sure there's a reason, but I can't figure out what it is. How do you keep it from impeding the rotation of the rocks around the pan? I've been thinking of how I might install a 2-4in pvc pipe in the center of the pan to try to prevent dishing of the pan - do you think it would be worth doing?
Most of the slabs I jiggle are too big to fit into a 6" circle and I've found that rubber rings around the rocks doesn't work because nodules with sharp-ish edges and a low slope tend to just work under the rings and toss them aside. So I don't do either and feel like the wood cross and rings eat up a good bit of valuable space in the pan. I've gotten up to 30 rocks into my 20" once by just taping them and don't have any problems in the grinding phases with tape coming off as long as I don't let the water/slurry get too deep. Too much water lessens the grind, anyhow. Typically I can do 20-25 at a time unless I'm doing some really big slabs or nodules for display. The only time I go to super sticky tape is when doing the second side of a slab. The polished side is really slick, so outdoor rated duct tape is a must. Plus, I tend to end up with my polish pan on the wet side from constantly spraying tin oxide off the sides of the rocks to save $$.
I never tried glue on slabs because it seeps into softer rocks, like jasper, and discolors them. Taping isn't as time consuming as it sounds - you get real good at it real fast. You do need to be careful pulling it off but it's usually pretty wet and, as long as you don't try to pull it UP off the slab, you're pretty safe. Some of the stick-um gets left behind, but that comes off easy by just taking one of the rolled up pieces of tape from the bottom of the weight and rubbing the leftovers off. Tape loves to stick to itself.
I only have one jiggler and 2 pans, so I wash out the grind pan after every batch/side. Too much grit or old grit more than 20 hours old doesn't do much of anything even if you add more new grit. The old stuff just gums it up. I only add grit once and only about 2 hours into the 60/90 grind. Just 2 or 3 tbsp. The 600 phase is the only one where you want the grit to wear down as fine as possible and might run it a long time or, better yet, repeat it.
I hear you about using the attached weights as "handles" when working the slabs on a wheel. Works great! With tape, though, I've found that there's always some fine grit dust left between the folds no matter how much you spray it off and it will pollute your polishing wheel leather/felt. Found that out the hard way.
The 4-bolt pillow blocks they use are the wrong bearing for the job. What you want is one of those 3-bolt stamped flange farm equipment bearings like came stock on the older Lortones. They are made for tough side to side stress like spinning an eccentrically weighted shaft. Found that out on my modified rig. The 4-bolt on the bottom of the pan base and also the 2-bolt one nearest my counterweight very soon developed a lot of slop. The rig was quiet as a mouse - not counting the low, hissing sound of the rocks sliding on the grit and the cooling fan for the motor - for a few days. Now, it sounds like someone idling a Harley on my back porch 24/7! Still works fine, so I'm taking my time on replacing the bearings. Not only is it a gritty job, but getting everything plumb and perpendicular was a real pita and I'm not in a hurry to be doing that again.
C-ya,
Rick