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[Picture Rocks]

Went OK overall, but some tuning is required. First - there is a big vibration caused by the drive belt. Maybe a segmented belt, or a new belt will reduce vibration. I checked other reasons like bent shaft, bearings, pulleys. The pulley bracket at engine seems a little squishy but I think it's meant to be like that otherwise the bearing will suffer.  Second - The blade is slightly dished and seems to be responsible for a bit of creep and uneven cutting across the slabs. Third - I love my rocks!!! Here they are...as well as the machine.

If you have any success changing over to a segmented belt I'd love to hear. The blade is likely toast unless I can find a cost effective repair. Can't imagine I can fix that myself without the proper tool. Otherwise, probably a 301 or similar.  https://www.barrancadiamonddirect.com/301-18-x-085-x-1-171918.htm?categoryId=-1

The Succor Creek Jasper was so hard the blade really struggled despite me sharpening the blade several times during cutting with an old grinder wheel. The other Oregon picture Jasper cut really well and took half the time as harder jasper

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[irockhound]

It looks like a hefty kerf blade.  I have had very good luck just hammering them out on a 12 ply slab of plywood.  I use a heavy leather mallet and work both sides back and forth.  I use a std hammer to get major corrections started but light taps with a metal hammer or it can introduce new problems..  They are never perfect after a repair but so close not to matter. 

[Picture Rocks]

It looks like a hefty kerf blade.  I have had very good luck just hammering them out on a 12 ply slab of plywood.  I use a heavy leather mallet and work both sides back and forth.  I use a std hammer to get major corrections started but light taps with a metal hammer or it can introduce new problems..  They are never perfect after a repair but so close not to matter.

Thanks, that's great to know, I'll try to do that. As long as it improves the drifting it will be worthwhile. I'm imagining they mount them on lathe and put equal pressure on both sides to flatten, if it's done commercially? I was hopeing to not have to buy a new blade so soon!

[vitzitziltecpatl]

Good saw.

We have one that didn't look nearly as good as yours when we got it about nine years ago. It has cut lots of rocks since then.

I like to use a 3 lb. deadblow hammer on a piece of plywood to straighten a blade. Just put a new 301 on our 18" saw. Have used 303s on our LS14, but think I'll put a 301 on it next time.

[irockhound]

I didn't say anything about the plywood type other than the ply and Vince didn't either.  I like to use a sanded grade so there are no imperfections in the surface that the hammer can bring out in the blade.  Smooth and flat just like you want your blade to be.

[Picture Rocks]

I like to use a sanded grade so there are no imperfections in the surface that the hammer can bring out in the blade.  Smooth and flat just like you want your blade to be.

Thanks for all your suggestions. Won't the kerf of the blade be a high edge and allow easy over corrections? I wonder if using something flat just inside the kerf edge will be better. By something I mean flat wood or metal. I have a solid steel disc (not a blade) that is flatter and sturdier than any piece of wood. Maybe that will work? I imagine a steel straight edge against the blade will tell me how far I need to correct.

Yes, I lucked out with the saw. No rust, just scraped paint. Just need to get blade straighter, vibration reduced, a mist shroud, and stand with recirculation bucket.

[irockhound]

Okay I guess more info would have helped.  Because most (not always) damage is from an unsharpened blade or cutting to fast or bad bearings etc most of the repairs tend to be dishing and light bends.  Almost all of this is fixable from working the blade without actually hitting the kerf area.  I also would never make a strike to the blade with a mallet or hammer with the edge of the strike on the edge of the kerf/blade joint as that is inviting trouble.  I will say I certain instances have used the mallet on the kerf making sure the blows are flat to not invite a new bend and that the strike also equally hits the blade and the kerf.  The main thing here is to remove the dish and in the process re work harden the blade to add some tensile strength back to the blade center.  As you work the blade with each strike you are actually over correcting but because of the tensile strength of the blade it will not simply bend with each strike but each one makes a minor change in the blade.  by working it over and over and then also flipping and doing both sides of the blade back and forth you end up in the middle so to speak.

[Picture Rocks]

  The difference experience makes! I get it now, thanks Steve. My blade is dished less than half a mm but still causes problems with the cut so it is worth trying to correct. However, since I'm sure to screw up the blade during the learning curve I'm going to get another blade first so at least I can still use the saw while I lick my wounds and take however long to straighten the dish. I saw the Highland Park video correcting a wobble on a new blade - do you think the technique of just grabbing and moving the blade with his hands will have the same effect on a dished blade? My blade is continuous rim and I don't know if the steel is softer or tensioned. Label is gone.

[Picture Rocks]

As usual there's a lot of info out there, now that I searched more and found this about rock saws:

http://www.lapidaryworld.com/pdf/rocksaws.pdf

Broke the rule of being attached solidly to base - that's why the vibration.

[irockhound]

The grab and bend can help with a bent blade but not a dished blade.  The type where the saw kept running but the blade stopped turning causing the blade to fold.  The dish due to improper alignment etc has had pressure applied under hot conditions to force the dish in the blade.  This heat and pressure changes the tensile strength on one side of the blade while the other side of the blade retains some of it's tensile strength causing the warp.  An interesting experiment is take an old blade and a propane torch and heat just one side of a blade on the ground and you can watch it curl up and create a dish without any pressure from a rock in a saw.   This is one reason why people flip their blades quite regularly so that the natural loss on strength in blades over time from cutting large or hard rock is happening on both sides of the blades.  Some notched blades can't be reversed if the diamond slots are at an angle and these blades normally have a direction arrow stamped into the blade or painted on.  Segmented and sintered blades don't have this issue and can be reversed (unless there is one out there I don't know about).

[Picture Rocks]

The grab and bend can help with a bent blade but not a dished blade.  The type where the saw kept running but the blade stopped turning causing the blade to fold.  The dish due to improper alignment etc has had pressure applied under hot conditions to force the dish in the blade.  This heat and pressure changes the tensile strength on one side of the blade while the other side of the blade retains some of it's tensile strength causing the warp.  An interesting experiment is take an old blade and a propane torch and heat just one side of a blade on the ground and you can watch it curl up and create a dish without any pressure from a rock in a saw.   This is one reason why people flip their blades quite regularly so that the natural loss on strength in blades over time from cutting large or hard rock is happening on both sides of the blades.  Some notched blades can't be reversed if the diamond slots are at an angle and these blades normally have a direction arrow stamped into the blade or painted on.  Segmented and sintered blades don't have this issue and can be reversed (unless there is one out there I don't know about).

Shouldn't there be a purpose built tool that would clamp in front of the spinning blade? It would be wishboned shape with two spinning drums or spheres tension clamped to the blade. It slides forward and backward as the blade spins, re-tensioning the steel and truing any dish. 3 min operation, ideally!!!