24" diamond blade questions

[zapins]

What diamond blade should I get for the saw I'm making?

I have seen segmented, continuous, and crimped edge kinds. I do not know what each one is best at cutting.

Which of these kinds should I buy and do you know of a decent & reasonably priced blade?

Blade thickness considerations?

I found this one on highland park's site for $150 which seems to be one of the cheapest blades of this size I've found. www.hplapidary.com/p/1027/greenline-24-inch-diamond-blade-160-inch-width-1-inch-arbor Would this be a good blade to buy?

[QuailRiver]

I've never used the HP Geenline blade but .160" is a very thick kerf for a 24" lapidary blade. By comparison the 24" BD-303S blade has a .100" kerf which is almost 1/16" thinner than the HP Greenline blade. So with using the HP Greenline blade - every 4 to 5 cuts you would loose the equivalent of the thickness of another whole slab. When slicing better grade lapidary materials, especially in sizes requiring a 24" saw, that additional loss of material from the thicker blade kerf will translate into $$$ lost very quickly. But if you plan on using your 24" saw only to reduce the size of large rocks to then slab in smaller sized saws then this might not be as much of a concern.

Larry C.

P.S. Also using a .160" kerf blade versus a .100" kerf blade you will be having to clean your saw out more frequently.

[zapins]

I see. So .100" is what I should shoot for when buying a blade.

What about crimped blades? I saw several on eaby for about 200 dollars but the crimped edges with embedded diamonds didn't look very high quality to me, compared with the embedded diamonds in metal continuous rim kind.

And segmented blades? Do they work, or chatter on stone? Are they suitable at all for lapidary work or just too thick & rough cutting?

[jamesp]

I personally would get a Diamond Pacific 303S. They are top of the line lapidary blades.
Blades last a long time, DP 303S cuts a smooth face, lasts.

I prefer segmented. I was asked by the saw maker(Covington) to increase the saw blade RPM for a segmented blade vs a continuos blade.
I think the segments allow ventilating the mud out of the cut.

Like my 303S.

[zapins]

Interesting. Thanks for the lead. I downloaded their PDF and read the saw recommendations, they are very helpful from a design point of view.

The price of the 24" blade on their catalog is $777. This is a little bit more than I had wanted to spend. Are there other blades that you have tried in the past that did an ok job that cost a bit less?

I'm glad you replied to my thread because I don't know if this is one of those areas where I have a choice between a good quality item that works or complete junk blades that break after a few uses with nothing in between or if there is a more graded range of blades from low end to high end. Is the difference between a $150 blade vs a ~$800 blade durability, safety, quality of cut, or something else?

I don't plan on using the blade every day, just a few times a year so longevity might not be that much of an issue for me.

[Deleted]

johnjsgems

[catmandewe]

If you are going to cut alot then the extra money spent on a good blade is worth it, if you are only going to cut occasionally a cheap crimped rim blade is probably OK. But there are also good crimped rim blades and bad crimped rim blades, it even varies from batch to batch so you have to be selective in which ones you buy.

Good luck...........Tony

[QuailRiver]

Diamond Pacific's 303S looks to be Barranca Diamond's 303S blade. JSGemsLapidary has the best price I've seen around lately on a BD-303S 24" blade at $544.
www.jsgemslapidary.com/BD-303S-24in-x-100in-x-1in-Blade/
The owner of JS Gems is a member of this site and is who Shotgunner linked in his post.

Larry C.

[Rockoonz]

If use is primarily to cut softer rock, like below Mohs 5, crimped may be OK.
zapins $777 is way too much, check with John. Keep in mind that a 303S will outlast 3 or 4 cheap crimped blades.

[zapins]

Thanks I'll check in with him and find out what he has in the next few days.

[johnjsgems]

Thanks all for the kind words. DP (and Covington) buys from Barranca/MK and are same blades. $777 is full list price. Check arbor size as the blades are 1" but can be ordered bushed to 3/4" or 5/8".

[zapins]

How many gallons of mineral oil do I need for a 24" blade?

Does it matter if the pan is shallow and wide or deep and narrow? In other words does the shape of the oil pan under the blade matter? I'm thinking of the rock sludge building up in a narrow deep pan vs a shallow wide one.

[TRG]

Great advice from everyone. I need to get a 24" blade as well but was hoping for a continuous blade like the MK professional. I can swear years ago I got a 18" MK that had a black label marked either Criterion or Professional. I haven't seen it since 2004/05? I tried to find a continuous 24" but seems like they are all segmented now? Zapins.. there isn't much a way around the spending cost in the $500 ballpark. You get what you pay for and you will be glad you got the thinner blade that cuts better and will last a long time. Once you get over the cost for the saw blade and the amount of oil **gulp** lol you can relax and enjoy each new slab in knowing your blade isn't going anywhere anytime soon. It will last for years or will pay itself off by being consistent. It's better to save up and start out with the right one. I just picked up a 24" Great Western and it's looking 15+ gallons of oil. I would go with the blade they recommended through Johnjsgems.

[zapins]

I'll see if I can save up for the blade. That might be several months away since I still need to construct the entire body of the saw.

So 15 gallons of oil is roughly the correct size for a 24" blade? I had read in the Lorton 18" saw manual they said to use 3 gallons of oil as coolant and keep 1/2" to 3/4" covered.

Is more oil necessary for some reason or just to ensure you have the right depth?

Also, when designing the bottom of the saw box I am trying to figure out if I can narrow the bottom down so that I don't need more oil than necessary. If I make the base narrow, say 5-6 inches wide and 50" long will that be enough room for the sediment to settle out? Or does the sediment in the oil need a wide bottom around the blade to settle down?

[cabjunky]

Look at the design of the frantom park to minimize the amount of oil needed. My Hp 24"requires 15 gallons to fill to the proper depth, without bricks, 2×4's, conex boxes, or a small nissan placed in the saw to limit the amount of oil required. Numerous people do this, but it requires you to clean out your saw more frequently......there is always consequences to anything you do.
I have been running a hp greenline agate eater on my 24" for the last three seasons, and aside from the kerf, it has performed flawlessly, smooth cuts, and extremly economical. As i said earlier always consequences.
good luck with your build.

[Rockoonz]

Sorry, not the best picture, but you can see the stepped tub on a 24 inch FranTom. Mine takes about 6 gallons. I wouldn't want less, the oil acts as a coolant and if you get it too hot it's going to wear the blade out faster.
I get 55 gallon drums of saw oil for about the same price I pay for a 24 inch 303S blade.

[zapins]

Fair enough answer.

I was thinking of a 6 gallon reservoir. Ultimately I'd like to make myself a centrifugal cleaning machine. I can cast it out of aluminum and lathe it into the right shape. It doesn't look very complicated at all to make.

[johnjsgems]

I had a cut off barrel that held 10 gallons oil under my HP24. A submersible pump supplied oil to blade. There is no way to say how much oil for any particular saw as all designs vary. You need to cover bottom cutting rim. As said, the smaller the sump the less oil but oil will need filtering more often and oil will run hotter. Anyone with a Covington 10" saw can tell you the effects of a very narrow sump under the blade as far as filling up with sludge rapidly.