electricmonk
spending too much on rocks
Member since August 2011
Posts: 281
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Post by electricmonk on Aug 9, 2014 12:43:28 GMT -5
Can't recall the manufacturer of this particular saw. There are a couple of design flaws that I would like to address before I get the saw going again. The top of the vise carriage is on the same plane as the top of the saw blade stiffener. For a 20" saw the blade stiffener is very small in diameter. Additionally, the carriage only mounts to 3 points on the rails, leading to some instability. I was thinking of adding a 1" spacer mount that would allow for a second attachment point on the rail closest to the blade with the added benefit of being able to use a larger stiffener. Lee and I discussed it a couple of years back, this is the first time I have had it cleaned and disassembled enough to actually see what is going on. One of the benefits of the design is the sloped reservoir, it would lend itself to converting to a pumping system to continuously cycle fresh oil to the blade (that will have to wait until next year at best). Thanks! Erik
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Post by phil on Aug 9, 2014 12:51:32 GMT -5
Blade stiffener? I don't see a stiffener... or are you talking about the washers used to hold the blade on the arbor?
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electricmonk
spending too much on rocks
Member since August 2011
Posts: 281
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Post by electricmonk on Aug 9, 2014 13:01:44 GMT -5
Blade stiffener? I don't see a stiffener... or are you talking about the washers used to hold the blade on the arbor? Sorry yes, my understanding is that a 20" saw should have a much larger washer than it currently does. I recall hearing it referred to as a stiffener...well, its possible I made that up
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Post by johnjsgems on Aug 9, 2014 14:05:55 GMT -5
Minimum 1/6 blade diameter. They are called "flanges".
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electricmonk
spending too much on rocks
Member since August 2011
Posts: 281
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Post by electricmonk on Aug 9, 2014 14:46:20 GMT -5
Minimum 1/6 blade diameter. They are called "flanges". Thanks! Basically I was hoping to engineer the mount so that I could have a larger flange than is currently present. I actually managed to put a rock in there at one point that was a bit below the height of the carriage and it ended up shearing some of the existing flange off. Not a situation I am eager to repeat.
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QuailRiver
fully equipped rock polisher
Member since May 2008
Posts: 1,634
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Post by QuailRiver on Aug 9, 2014 16:35:09 GMT -5
Maybe it's just photo distortion but the arbor flange and flange washer do look small for a 20" blade. What is the diameter of the flange on this saw? Also when I have a rock that hangs down a little and looks like it might hit the flange washer I place two or three pieces of 1/4" thick masonite underneath the rock in the vise to raise the elevation of the rock a little. Larry C.
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Post by phil on Aug 9, 2014 19:49:34 GMT -5
Looks like someone, at some point, swapped out the correct sized arbor for one from a smaller saw in order to get another inch or so of cutting depth. John can probably sell you the right flanges. Too small a flange can mean you trash blades faster than they do normally. To me, with todays cost of blades, it's a very bad tradeoff. A 20 inch saw maximum rock thickness to cut should be about 6.5 inches.Figure 1/3 the diameter of the blade, then it'll hit the flange or come dang close. People also tend to forget the rock also extends to the same height on the blade on the inside. I had a "student" who was in training to become a lapidary instructor, who kept clamping in over large rocks and wondering why the saw would only cut part way then hang up, or worse, start hitting the inner flange and making one heck of a racket. I'd look, turn off the saw and tell her it was too large, take it out. She'd look, ignore me, and try try try. She failed every time. A couple months later, I got tired of beating a dead horse and resigned. She's still there, and the equipment had taken a real beating, she can't even change out blades right. She just won't listen, and I got tired of fixing things she broke. So, to sum things up, yes those are too small they should be approx 2 1/2 inches in diameter.
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electricmonk
spending too much on rocks
Member since August 2011
Posts: 281
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Post by electricmonk on Aug 9, 2014 22:33:43 GMT -5
Maybe it's just photo distortion but the arbor flange and flange washer do look small for a 20" blade. What is the diameter of the flange on this saw? Also when I have a rock that hangs down a little and looks like it might hit the flange washer I place two or three pieces of 1/4" thick masonite underneath the rock in the vise to raise the elevation of the rock a little. Larry C. The flange is only 2.5" (well...2 a shy 7/16" after colliding with the rock I mentioned)...not nearly large enough for the blade size. The other thing I considered was possibly replacing the bearing block assembly. I just got it removed, having used a heat gun to remove about 10 lbs of silicone that was used to mummify the bearing block. It would require a modification of the sheet metal but not that big a deal. I think I could possibly lower the assembly about 1", perhaps a bit less if I did so. Hate to go to that extreme if I could just raise the carriage up about the same amount. That should give me a comfortable 3.5" - 4" flange before it runs the risk of being on the same plane as the carriage surface. Thanks for the tip on the masonite, does it tend to soak up oil?
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electricmonk
spending too much on rocks
Member since August 2011
Posts: 281
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Post by electricmonk on Aug 9, 2014 22:37:38 GMT -5
Looks like someone, at some point, swapped out the correct sized arbor for one from a smaller saw in order to get another inch or so of cutting depth. John can probably sell you the right flanges. Too small a flange can mean you trash blades faster than they do normally. To me, with todays cost of blades, it's a very bad tradeoff. A 20 inch saw maximum rock thickness to cut should be about 6.5 inches.Figure 1/3 the diameter of the blade, then it'll hit the flange or come dang close. People also tend to forget the rock also extends to the same height on the blade on the inside. I had a "student" who was in training to become a lapidary instructor, who kept clamping in over large rocks and wondering why the saw would only cut part way then hang up, or worse, start hitting the inner flange and making one heck of a racket. I'd look, turn off the saw and tell her it was too large, take it out. She'd look, ignore me, and try try try. She failed every time. A couple months later, I got tired of beating a dead horse and resigned. She's still there, and the equipment had taken a real beating, she can't even change out blades right. She just won't listen, and I got tired of fixing things she broke. So, to sum things up, yes those are too small they should be approx 2 1/2 inches in diameter. Phil, the flange does measure 2.5" currently, minus the shave I gave to it. Can't say for sure that the arbor was swapped but it looks original based on the hole configuration and lack of evidence of modification to the sheet metal. The previous owner did remove the clutch assembly on the right hand side that was some form of power feed. He replaced it with a motor in the rear that drives the all thread shaft. Its been a few years so I don't recall the particulars.
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Post by roy on Aug 9, 2014 23:54:56 GMT -5
to me the arbor looks wrong the shaft on my 18 is 3/4 in thickness yours looks like 1/2 also it looks higher than any i have see some one may have tried to convert a 18 to a 20???
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vugs
starting to spend too much on rocks
Rockbiter
Member since February 2014
Posts: 225
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Post by vugs on Aug 10, 2014 0:08:32 GMT -5
cigarboxrock.com will machine you a custom flange piece if you provide the dimensions you need. I've always thought their attention to detail is top notch.
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electricmonk
spending too much on rocks
Member since August 2011
Posts: 281
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Post by electricmonk on Aug 10, 2014 2:22:46 GMT -5
Arbor shaft is 3/4", I wonder if perhaps its the camera perspective that is making it look so smallish.
The only reason I think that it is the original is that it perfectly lines up with the only cutout (no repairs) for the arbor. It is a pretty tall arbor, its actually aluminum and mostly hollow.
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electricmonk
spending too much on rocks
Member since August 2011
Posts: 281
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Post by electricmonk on Aug 10, 2014 2:23:12 GMT -5
cigarboxrock.com will machine you a custom flange piece if you provide the dimensions you need. I've always thought their attention to detail is top notch. Great, thanks a bunch for that link! I get to Bend on occasion for work so that makes it even sweeter.
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vugs
starting to spend too much on rocks
Rockbiter
Member since February 2014
Posts: 225
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Post by vugs on Aug 10, 2014 14:43:54 GMT -5
cigarboxrock.com will machine you a custom flange piece if you provide the dimensions you need. I've always thought their attention to detail is top notch. Great, thanks a bunch for that link! I get to Bend on occasion for work so that makes it even sweeter. no problem.. glad it was useful.
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Post by Rockoonz on Aug 10, 2014 15:42:36 GMT -5
It is a Hilquist saw. It is interesting in that it was the first larger slab saw I purchased and I sold it to the person who Eric bought it from. I thought the original fiberglass tub had been replaced by a well made steel box, but since then I have discovered that Hilquist sold build it yourself kits in the day.
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QuailRiver
fully equipped rock polisher
Member since May 2008
Posts: 1,634
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Post by QuailRiver on Aug 11, 2014 0:43:48 GMT -5
The arbor Flanges and Flange Washers on my 18" Lortone and 20" Covington Saws are 3" in diameter. If there is enough depth between the bottom edge of your blade and the bottom of your oil reservoir to lower the arbor an inch or so, you could just remove the bearing/arbor assembly on yours and replace it with a Lortone or Covington arbor mounted in standard pillow block bearings like the Lortone 18" saws use. Other than drilling new mounting holes for the pillow block bearings the only other modification you would have to make would be to cut a new hole in the sheet metal where the arbor protrudes though the side and screw a small piece of sheet metal or acrylic over the old arbor hole. And yes the masonite does soak up some oil but that doesn't hurt anything. Larry C. Maybe it's just photo distortion but the arbor flange and flange washer do look small for a 20" blade. What is the diameter of the flange on this saw? Also when I have a rock that hangs down a little and looks like it might hit the flange washer I place two or three pieces of 1/4" thick masonite underneath the rock in the vise to raise the elevation of the rock a little. Larry C. The flange is only 2.5" (well...2 a shy 7/16" after colliding with the rock I mentioned)...not nearly large enough for the blade size. The other thing I considered was possibly replacing the bearing block assembly. I just got it removed, having used a heat gun to remove about 10 lbs of silicone that was used to mummify the bearing block. It would require a modification of the sheet metal but not that big a deal. I think I could possibly lower the assembly about 1", perhaps a bit less if I did so. Hate to go to that extreme if I could just raise the carriage up about the same amount. That should give me a comfortable 3.5" - 4" flange before it runs the risk of being on the same plane as the carriage surface. Thanks for the tip on the masonite, does it tend to soak up oil?
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