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Gadgets, Gizmos, and Dohickeys => Cutting, Grinding, Polishing => Topic started by: womanwithatorch on July 15, 2016, 12:10:13 PM

Title: blade size for trim saw
Post by: womanwithatorch on July 15, 2016, 12:10:13 PM
Is there any reason not to replace the 6" blade in my 6" trim saw with a 4" blade? I'm thinking the 4" would reduce wobble and spray.
Title: Re: blade size for trim saw
Post by: jakesrocks on July 15, 2016, 12:44:24 PM
4" blades are usually pretty thin. Easy to bend if you get too aggressive trimming. As long as all you're only trimming preforms, and not trying to slab with them you should be OK. Maybe buy a couple of those cheap Chinese blades to use until you get the feel of them.

Do you have a spray guard over your 6" blade, and if so can it be lowered enough to catch spray from the smaller blade ?
Title: Re: blade size for trim saw
Post by: peruano on July 15, 2016, 01:38:52 PM
Realize that by changing the saw blade diameter you are decreasing the saw blade's circumference significantly, effectively slowing the diamonds rushing by your stone being cut.  Hence many saw blades can be calculated to the measure of feet per second but the short answer is that it might be best to speed up your rpms to compensate for that slower/lower effective speed on the outer margin of your blade.  And a bit more water or oil in the saw to contact the blade. 
Title: Re: blade size for trim saw
Post by: vitzitziltecpatl on July 15, 2016, 05:13:44 PM
Hi. Am assuming the wobble in your blade isn't from being slightly bent, and that you have the largest possble washers on each side. Would personally try adding "skirts" of some sort to the blade guard to reduce spray before going to a smaller blade. This can reduce visibility, but you might find a balance that works for you.
Title: Re: blade size for trim saw
Post by: Slabbercabber on July 16, 2016, 04:55:23 AM
There are many ways to reduce spray.  First be sure you have a blade cover that comes down as far as practical in front.  I also use a plexiglass shield attached to the front of the table.  If your six inch blade wobbles, something is wrong.  Going to a smaller thinner blade will not help except that it will be new and straight.  Better would be to find the reason for and correct the cause.  Is the blade bent?  Are your flanges square and flat?  Is your arbor nut ground or is it a plain old hex nut that someone threw on to replace the original precision ground nut?  Does your blade match the arbor size?
Title: Re: blade size for trim saw
Post by: womanwithatorch on July 17, 2016, 04:45:46 AM
Thanks everyone for your thoughtful answers. Now I have new information to consider before making a decision on blade purchase. I'm glad I asked the question, it isn't as simple I thought. I appreciate the help.
Title: Re: blade size for trim saw
Post by: johnjsgems on July 18, 2016, 10:11:09 AM
My first trim saw was an old Frantom 10".  Covington had 8" discontinued blades on sale so I bought one.  My blade guard was adjustable but I could not keep it from spraying oil with the 8" blade.  With a 10" I could keep it at a steady drip at blade guard.  If your 6" blade wobbles but not bent you may be overtightening the blade nut.  Just tight enough to stop blade from slipping.  Also, blade flange washer needs to be minimum 1/6 blade diameter to properly support blade.  The last Chinese blade I put on my old Frantom wobbled no matter what.  I switched to MK and never went back.  If your blade ran straight but now doesn't you may have ether over heated it and lost tension or bent it a little.  Remove it and lay on flat surface to check.  A smaller blade likely won't help with whatever is wrong.  I recently found an issue with the drop saw line I recently bought and build.  I received the arbors with inner flanges pressed on and supposedly machined flat.  All were off by at least .002" and some as much as .006".  After re-machining flat no more blade wobble.  If your inner flange washer is not fixed make sure it is clean before installing blade.