jamesp
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Post by jamesp on Jul 20, 2014 12:30:49 GMT -5
Saw stopped feeding. Noticed the threads gone on the thread clamp that grips the lead screw. So I ran the ziz wheel up against the bench grinder till I reduced it's diameter to match the lead screw diameter. Then re-grooved the threads on each half. 2nd time, last one ran for 2 years.
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Post by Drummond Island Rocks on Jul 20, 2014 13:11:34 GMT -5
so are they just straight parallel groves then? I assumed they were standard threads on those clamps to match the threads on the feed rod like 1/2"-20 fine. Mine has been shot for over a year so I have just been using a home depot metal spring clamp in front of my vise. It works but if I could fix my old one I would.
Chuck
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jamesp
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Post by jamesp on Jul 20, 2014 13:28:56 GMT -5
so are they just straight parallel groves then? I assumed they were standard threads on those clamps to match the threads on the feed rod like 1/2"-20 fine. Mine has been shot for over a year so I have just been using a home depot metal spring clamp in front of my vise. It works but if I could fix my old one I would. Chuck Chuck, the thread groves are at a slant. I just carefully put little reference notches to match the pitch at the top of the saddle. Them dove the ziz wheel in the saddle using the reference notches as a guide. Make sense ? As it runs it seems to imbed, the clamp softer bronze, and the lead screw is harder steel. It makes more of a square thread at first. Maybe they are called ACME threads ?? The vice clamp is the same type clamp and it got an overhaul too. Been cutting some large corals and they are stubborn, if you know what I mean. I ground the ziz wheel to the diameter of the outside of the threads on the lead screw.... I just cut through a head that was taller than the saw blade, so it passed the test.
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quartz
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Post by quartz on Jul 20, 2014 23:02:07 GMT -5
No matter what you call it: "Where there is the will, there is a way". Or: "Any port in a storm". That is some class homebrewed machine work.
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Post by Rockoonz on Jul 21, 2014 0:35:25 GMT -5
jamesp inthat huge shop of yours you don't have a tap set? I just grind down the half nuts a little so it will close farther, clamp it shut and run a tap through it. Most saws take 1/2-20, some smaller ones use 1/4-20, I suppose some use 5/16 or 3/8 as well but I like 20 threads per inch because it's easier ti do the math for vice travel speed.
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jamesp
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Post by jamesp on Jul 21, 2014 2:45:10 GMT -5
jamesp inthat huge shop of yours you don't have a tap set? I just grind down the half nuts a little so it will close farther, clamp it shut and run a tap through it. Most saws take 1/2-20, some smaller ones use 1/4-20, I suppose some use 5/16 or 3/8 as well but I like 20 threads per inch because it's easier ti do the math for vice travel speed. I am laughing at my self. Why not use a tap ?!@#$ I thought I had common sense. The curse of being a degreed engineer. Maybe I should have been a dentist...I guess I grind and weld too much. Thanks Lee.
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jamesp
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Post by jamesp on Jul 21, 2014 2:47:50 GMT -5
No matter what you call it: "Where there is the will, there is a way". Or: "Any port in a storm". That is some class homebrewed machine work. I asked for that Larry. Lee just took a chunk out of me too. I love doing stupid stuff. Dang machinists
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roundrock
noticing nice landscape pebbles
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Post by roundrock on Jul 21, 2014 10:12:29 GMT -5
But jamesp it's been said that out of what some think as stupid comes brilliance. Dance with the one that brung you.
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jamesp
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Post by jamesp on Jul 21, 2014 11:42:08 GMT -5
But jamesp it's been said that out of what some think as stupid comes brilliance. Dance with the one that brung you. It can be a good social assist to do things 'By Way of Omaha' also. Many tech people hemorrhage over doing things 'uniquely'. I have been known to bait them in such a way. In this case my guest would be dancing with stupid. And had a 1/2-20 tap and vise not 10 feet away. It's OK, I am amused more than the ones that would have done the job logically. And appreciate them pointing out smart.
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bhiatt
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Post by bhiatt on Jul 21, 2014 11:51:54 GMT -5
taps are for sissy's. Now the grinder method...that's impressive.
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jamesp
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Post by jamesp on Jul 21, 2014 12:28:11 GMT -5
taps are for sissy's. Now the grinder method...that's impressive. Brad likes big hammers(chain gang). Not really.
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Post by johnjsgems on Jul 21, 2014 16:59:18 GMT -5
BD saws are mostly 5/8"-11 I think. If it was a worm gear drive it would have a directional taper I think. It is a "screw drive" so standard threads. At least two years later you can remember how you fixed it last time.
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jamesp
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Post by jamesp on Jul 21, 2014 18:56:31 GMT -5
BD saws are mostly 5/8"-11 I think. If it was a worm gear drive it would have a directional taper I think. It is a "screw drive" so standard threads. At least two years later you can remember how you fixed it last time. That Covington saw is not over built. But is easy to adjust and reliable. Little 1/2 HP motor does well if it is cutting straight. The only thing that has worn out was the thread clamps which helped the memory situation. Seems a little under powered, makes you keep adjusted to cut straight. Motor lugs if blade needs dressing or cutting crooked. Fair enough.
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quartz
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Post by quartz on Jul 21, 2014 23:36:15 GMT -5
Didn't mean that as "taking a chunk out of you", sorta made the assumption no tap available. I thought the method was pretty creative. Larry
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Post by rockpickerforever on Jul 21, 2014 23:58:08 GMT -5
jamesp inthat huge shop of yours you don't have a tap set? I just grind down the half nuts a little so it will close farther, clamp it shut and run a tap through it. Most saws take 1/2-20, some smaller ones use 1/4-20, I suppose some use 5/16 or 3/8 as well but I like 20 threads per inch because it's easier ti do the math for vice travel speed. Ha ha, Lee I was thinking the same thing, lol. Kinda seems this was the long way around, the scenic tour, if you will. What the heck, you got the job done, James.
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jamesp
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Post by jamesp on Jul 22, 2014 0:51:14 GMT -5
Didn't mean that as "taking a chunk out of you", sorta made the assumption no tap available. I thought the method was pretty creative. Larry It was creative looking back. But when I saw the word tap I knew I went the long way. And started laughing. Still am.
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jamesp
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Post by jamesp on Jul 22, 2014 1:04:49 GMT -5
jamesp inthat huge shop of yours you don't have a tap set? I just grind down the half nuts a little so it will close farther, clamp it shut and run a tap through it. Most saws take 1/2-20, some smaller ones use 1/4-20, I suppose some use 5/16 or 3/8 as well but I like 20 threads per inch because it's easier ti do the math for vice travel speed. Ha ha, Lee I was thinking the same thing, lol. Kinda seems this was the long way around, the scenic tour, if you will. What the heck, you got the job done, James. OK Missy, get out the ball bat. Production was found to increase in an experiment performed in Japan. They made a full sized doll that looked like the supervisor. At break time they let the workers beat it with a stick as it hung from a rope to vent their frustrations. Take a guess on their productivity output. Not that much difference...they are just threads
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jamesp
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Post by jamesp on Jul 22, 2014 1:20:59 GMT -5
Another example Jean
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jamesp
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Post by jamesp on Jul 22, 2014 1:29:11 GMT -5
I should patent these new threads
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jamesp
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Post by jamesp on Jul 22, 2014 1:33:28 GMT -5
I did realign and tighten the slack out of my Covington saw carriage and it cuts with about a 400 grit finish and no blade marks. I should get some credit for that accomplishment.
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