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Malcolm Wheeler
06-05-2012, 9:14 PM
I have a Grizzly 513X2BF - it calls for 131 1/2 inch blades. The local Laguna dealer sells a 132" Resaw King. I called Grizzly customer care to ask what the maximum and minimum specs are for blade length and he said he did not have any.

Given the Laguna resaw blade really has to be high tension, I am worried that the 1/2 inch will not allow me to tension the blade fully.

What sayeth the Creek? Will the half inch make a huge difference?

regards
Malcolm

Phil Thien
06-05-2012, 9:19 PM
First, measure your actual saw. Use a piece of string. Release all the tension first, and wrap the string around both wheels, and mark the end.

Don't pull the string too tight, you don't want to stretch it. Measure the string and you will know whether the shorter band will fit.

If the blade fits the saw, you will be able to tension it fine. The only problem with tensioning would be if the blade was a bit longer than spec. A bit shorter, but still fitting the saw, should be fine.

Scott Haddix
06-05-2012, 9:25 PM
Unless the local dealer is offering a fantastic price, I'd order directly from Laguna and have them make it the correct length. They've made two blades for my Grizzly bandsaw, including a resaw king. Now, if the local dealer's price is much better, I'd think a 1/2 inch would be okay myself. Across the two sides that equals a 1/4" of travel on the wheel, and I have to think you've got that much room.

Rick Fisher
06-06-2012, 2:08 AM
Their should be more than enough range in the saw, figuring that the 131-1/2 is the center of the adjustment.. Having said that, its a good idea to measure it yourself..

+

Floyd Mah
06-06-2012, 2:36 AM
Here's the relevant math. Assume that your new bandsaw blade is 1/2" longer. If you don't change the wheels to larger wheels (about 3/16" increase in diameter each wheel would do), then you must increase the separation between the wheels by 1/2" divided by 2, or 1/4". For the sake of calculation, assume that the screw adjustment has an 18 pitch thread. This would mean that you would have to turn the crank slightly more than four full turns to get the same tension on the blade. You can test this by noting the position of the crank with a 131.5" blade, take the blade off (or just slip it off the wheels) and then reposition the crank and see how much more adjustment you have left. If the pitch of the adjustment screw is different, change the number of turns (to get 1/4" adjustment).

Chris Fournier
06-06-2012, 9:33 PM
Find a local supplier of tooling and have them weld up the blades that you want. To the point and likely the best value solution. I'd never buy a blde from an equipment manufacturer as their pricing is rarely good value.

Leo Graywacz
06-06-2012, 9:52 PM
Here's the relevant math. Assume that your new bandsaw blade is 1/2" longer. If you don't change the wheels to larger wheels (about 3/16" increase in diameter each wheel would do), then you must increase the separation between the wheels by 1/2" divided by 2, or 1/4". For the sake of calculation, assume that the screw adjustment has an 18 pitch thread. This would mean that you would have to turn the crank slightly more than four full turns to get the same tension on the blade. You can test this by noting the position of the crank with a 131.5" blade, take the blade off (or just slip it off the wheels) and then reposition the crank and see how much more adjustment you have left. If the pitch of the adjustment screw is different, change the number of turns (to get 1/4" adjustment).

Not exactly correct. If the band is 1/2" longer in circular length then you need to divide it by Pi to find out how much you need to have the tensioning wheel up. So it is essentially 1/3rd of that 1/2", not even 3/16". I'm pretty sure you should be able to raise your tensioning wheel that much.

Bruce Wrenn
06-06-2012, 9:54 PM
You can buy a "flat back" tape from FastCap. It's designed to measure around curves, so measuring exact length isn't a problem.

Floyd Mah
06-07-2012, 12:55 AM
Sorry Leo, but that's not correct. If the wheels are unchanged, the extra length goes to the straight part of the blade, not the curved parts. Since there is 1/2" extra length, 1/4" goes to each side. Hence the wheels need to be moved 1/4" farther apart. Here's a visual: Draw an outline of a track. Cut the track in half through the straight parts. Move the halves 1/4" apart. Now the distance around the track is 1/2" longer. The circular parts at the end of the track are unchanged.

Once you throw pi into the calculations, you are now trying to accommodate the extra length by making the wheels bigger. (Without moving the wheels apart). If you expand the both wheels' circumference by 1/2" you would need the new diameter to be the old diameter + 1/2 divided by pi (3.14159),
C=pi * old_diameter, then C + 1/2 = pi * new_diameter.
gives you the new_diameter = old_diameter + 1/2 divided by pi. Or roughly 3/16" greater diameter.

Save the money for the tape measure and buy something useful.

John Coloccia
06-07-2012, 5:18 AM
Just have the dealer order a 131.5" blade and be done with it.

Malcolm Wheeler
06-07-2012, 2:02 PM
Thank you for the feedback. I think I will get a custom length made, but in the meantime I will use cheaper steel resaw blads (which unfortunately leave a very rough finish)

David Helm
06-07-2012, 6:09 PM
+1 on going to a local saw shop and having the blades made up there. Been doing that for decades. Beats mail order because you talk directly with the maker and have instant accountability.

Matt McColley
06-08-2012, 1:49 PM
Timber Wolf will make up a blade to whatever length you tell them

Prashun Patel
06-08-2012, 2:13 PM
Everyone's got their favorite blade supplier. Mine is Bandsawblades direct. They cut them custom, they're reasonable quality, and if you get 10, shipping's free. They're outa FL.

Curt Harms
06-09-2012, 7:49 AM
Thank you for the feedback. I think I will get a custom length made, but in the meantime I will use cheaper steel resaw blads (which unfortunately leave a very rough finish)

Have you considered blades made with Atlanta Sharptech stock like Highland Hardware's Wood Slicer or Iturra or Spectrum Supply's versions? They won't last as long as a Carbide blade especially with hard-on-blades wood species like teak but the upfront cost is quite a bit less and there are no tension issues. Cut quality from those blades is reported as excellent – little set so as not much in the way of 'scratches'. Just don't try to cut curves with 'em.