Lenox tri-master for 21" saw? (g0531/w1770)

[Jared Sankovich]

Wondering if anyone successfully tensioned a 1" carbide blade on the 21" grizzly/shopfox saws. I'm about to order a carbide resaw blade for a w1770 I have, but don't want to order something it can't effectively tension.

I guess i should just buy a tension gauge either way.

[Mike Cutler]

Jared
I've had a Lennox 2/3 Vari pitch, 1" TriMaster ,blade on my 18" Rikon since 2005, and it resaws very well. I can't imagine that either of those two bandsaws, which are in every way bigger/better than mine, could not tension a 1" TriMaster blade for resaw.

Skip buying the tension meter and use the OEM tension indicator as a starting point and adjust from there, based on results. Make sure there are gaps between the tension spring coils when you're done.
I personally think you'll be fine.

BTW
The TriMaster is wicked expensive, but the results are worth it.:D

[Tom M King]

Since you're able to run a 1" blade, get one that's designed for cutting wood- Lenox 1" Woodmaster Ct 1.3 tpi. I'd advise to have a helper, who is used to handling the outfeed, the first time you run it, because it will cut so fast, and easy that it might be a big surprise.

[Dave Cav]

I ran a 1" Woodmaster CT on a 17" Grizzly and it worked OK, although a 3/4" probably would have been better. I was maxing out the tension on the 17" saw. I'm using a 20" MM now and it doesn't have ANY problem tensioning a 1" blade.

I'll agree the Trimaster is probably overkill for woodworking. The Woodmaster CT works fine, cuts fast, and is expensive enough as it is.

[John TenEyck]

I'm quite sure you can easily tension a 1" carbide blade on the G0531. The specs. say it can handle a 1-3/8" blade. To me that means it can take a 1-1/4" blade, so 1" should be no problem at all. BTW, those specs. are the same as for my G0636X bandsaw and I had no trouble putting 27K psi on a 1" Woodmaster CT at the factory setting. And as Dave said, the 1" x 1.3 tpi Woodmaster CT cuts so fast (and smooth) you better have someone ready to catch what's coming off the other side.

John

[Van Huskey]

The G0531 is one of the few Grizzly saws I have not been able to actually run. One thing to note is the blade width capacity rarely coincides with what a saw can tension but rather what blade width can be mounted on the tires and the guides can accommodate. This is particularly true when you are using a carbide tipped blade since it needs roughly twice the spring tension of a similarly sized carbon blade. So the vast majority of the time one is left to the anecdotal information on the web or the use of a strain gauge, whether commercial or shop made.

I have used the G0569 which is a similarly built 24" saw. Based on my experience with it and comparing the 569 and 531 in the showrooms it should not be an issue getting the 1" Trimaster up to at least 25K psi if not a little more. This is in the area where it has more beam strength than a 3/4" Trimaster at 30K so I would indeed go with the 1".

The Trimaster gives a better finish off the saw than the CT and there are at least 2 places that will sharpen the Trimaster but I not aware of one that sharpens the CT, in any event it has smaller carbide teeth. The Trimaster and Laguna Resaw King are my favorite carbide blades and resharpening is one of the big reasons why.

[John TenEyck]

Connecticut Tool and Saw sharpens Woodmaster CT blades, other carbide BS blades, and much more.

http://ctsaw.com/

John

[Jared Sankovich]

Thanks everyone for the responses.

Just out of curiosity I grabbed one of my .0001 indicators and checked the stretch of a 1" carbon blade (.885"x.033") .0045" stretch over 2.5"

By my math that would be 1478.3 lbs of force. There is inherently some slop in the accuracy of this setup but I'm pleased with what I measured.

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[Van Huskey]

My gut tells me the measurement is flawed, maybe by a factor of two. Using that strain and Young's modulus that equates to 52,200 psi. This works out to a spring pressure of over 3,000 pounds and a band pressure just over 1,500 which is basically what you calculated.

[Jared Sankovich]

My gut tells me the measurement is flawed, maybe by a factor of two. Using that strain and Young's modulus that equates to 52,200 psi. This works out to a spring pressure of over 3,000 pounds and a band pressure just over 1,500 which is basically what you calculated.

I had the same thought. I went back and maxed out the tension and measured .0054" of stretch over 2.5" which would roughly be 62,000 psi. Assuming I'm off by a factor of two it's still 31k.

I can just about hang off the quick release lever at that level before it moves. (Not coil bound)

[John C Bush]

I have the Griz 531B(not sure of the difference with the 531) and use the Woodmaster CT 1-3 all the time. I don't have a tension guage so I go with the built-in guage as is. The CT has worked well for me--worn out three of them in 6+ years of hobby resawing. I may step up to the trimaster next time to see if there is any difference in performance.Good luck.

[David Kumm]

I'd start with the lower priced CT. I've had saws that could tension but when resawing and putting additional load on the machine started to flex just enough to cause the blade to wander. A Lenox carbide blade will resaw at 15-20,000 but just not as well or as fast as when under higher tension. In addition to the frame itself, you need to consider the build strength of the upper wheel assembly, the spindle, and the load capability of the bearings, especially the bearings. Running a 1" blade at high tension stresses all of those components so you don't want to push the limits of the machine unless only occasionally. Dave

[Van Huskey]

I had the same thought. I went back and maxed out the tension and measured .0054" of stretch over 2.5" which would roughly be 62,000 psi. Assuming I'm off by a factor of two it's still 31k.

I can just about hang off the quick release lever at that level before it moves. (Not coil bound)

Yep, 62,640 psi. As you say even if somehow it is off by a factor of two you still have plenty of tension. As Dave mentions be mindful of what you are doing to the frame/tension assembly. In any case those numbers are impressive, higher than I have ever seen on a woodcutting saw and while I have never tried to get more than ~30Kpsi I never thought I had near that much left. While I have that gut feeling it is wrong the fact you were able to repeat it and most of the errors in method tend to produce LOWER numbers along with the fact it would require a micrometer to be farther off than I have ever seen leads me to think it is indeed capable of massive tensions.

[Jared Sankovich]

I'd start with the lower priced CT. I've had saws that could tension but when resawing and putting additional load on the machine started to flex just enough to cause the blade to wander. A Lenox carbide blade will resaw at 15-20,000 but just not as well or as fast as when under higher tension. In addition to the frame itself, you need to consider the build strength of the upper wheel assembly, the spindle, and the load capability of the bearings, especially the bearings. Running a 1" blade at high tension stresses all of those components so you don't want to push the limits of the machine unless only occasionally. Dave

Your post made me wonder about the build so I checked the wheel bearings. The 21 has 6205, the 24 and 17/19 636/700 have much heavier 6306s. I'd say that is likely indicative of the differences in real world tensioning capability.

[John TenEyck]

I would be interested to see your results if you put a 4 or 5 inch extension or spacer block on your dial indicator and stop so that you are measuring strain over a much longer gage length. The longer the gage length to more accurate your results will be. If you don't have an extension use a piece of wood or something similar and definitely not a piece of aluminum which will expand/contract more than you can imagine if you grab hold of it.

John

[Jared Sankovich]

Yep, 62,640 psi. As you say even if somehow it is off by a factor of two you still have plenty of tension. As Dave mentions be mindful of what you are doing to the frame/tension assembly. In any case those numbers are impressive, higher than I have ever seen on a woodcutting saw and while I have never tried to get more than ~30Kpsi I never thought I had near that much left. While I have that gut feeling it is wrong the fact you were able to repeat it and most of the errors in method tend to produce LOWER numbers along with the fact it would require a micrometer to be farther off than I have ever seen leads me to think it is indeed capable of massive tensions.

I'm a bit surprised myself. The dial indicator is decent, I'd be suprised if it was off more than .0002 off
The overall setup would likely be far more suspect, but it's relatively straight forward.

[Van Huskey]

Like I said most setup issues result in low readings not high. Again, I am not saying your reading is not accurate, it is just so far outside my experience that my gut can't help but be skeptical. I think even with a potential measurement issue you are probably more than good with a 1" carbide blade!

[Jared Sankovich]

I would be interested to see your results if you put a 4 or 5 inch extension or spacer block on your dial indicator and stop so that you are measuring strain over a much longer gage length. The longer the gage length to more accurate your results will be. If you don't have an extension use a piece of wood or something similar and definitely not a piece of aluminum which will expand/contract more than you can imagine if you grab hold of it.

John


Like I said most setup issues result in low readings not high. Again, I am not saying your reading is not accurate, it is just so far outside my experience that my gut can't help but be skeptical. I think even with a potential measurement issue you are probably more than good with a 1" carbide blade!


6.150" Center to center .0085 stretch for 40,552psi. That seems more in line with expectations.

I decided to throw another indicator on the saw and measure deflection at full tension. It was .080" towards the table.
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[John TenEyck]

6.150" Center to center .0085 stretch for 40,552psi. That seems more in line with expectations.

I decided to throw another indicator on the saw and measure deflection at full tension. It was .080" towards the table.
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Thanks for the follow-up info., Jared. 25 - 30K psi is plenty on the Woodmaster CT. Lowering the tension into that range will help reduce the frame bending, too. 0.080" is huge; I'll bet your upper blade guide was no longer parallel with the blade over it's full range. Personally, I wouldn't take it up to full tension again.

John