Tolerances for blade wobble??

[gjat]

The BT is an upgrade from a $99 craftsman 15 years ago, which was an upgrade from a circ saw. I'm impressed with alignment and everything and have checked it all with a dial indicator. My arbor is dead-on with no run-out at all. I did have a huge wobble initially, but polished the faces of the arbor washers and spacers and eliminated most of the wobble. I have installed some of my old 'no-name blades' I had from before, and they actually were better than the Ryobi blade as far as measurable wobble.

To finish the long story so as not to attempt to gild a lilly, at what point should I be satisifed with the Ryobi blade? How many 1,000's of an inch?

[gmack5]

Which Blade do you have?

I understand that the newer Saws have a Chinese knock-off Blade instead of the Frued Blade that used to come standard.

In any case a varience of more than .005 would not be acceptable to me.

[Ken Massingale]

Blade to miter slot/SMT variance, depending on saw brand, should be zero. That normally not being practical, as little as possible is the goal. I try to get to .001 and do with the WW II blade. With other blades I have to be happy with .002-.003. IMHO anything over .003 is too much.
ken

[gjat]

Thanks for the answers. It's the Chinese blade and I'm getting .007 wobble, while me cheapee Skil brand blade is .003. I called customer service and asked for a new blade.
But even so, I am extremely pleased with the smoothness of the cut and everything else. It may be a Chinese blade, but it's smoother than my $12 Skil blade. Maybe when I retire and can afford to be more serious about my hobby, I can buy a Freud. Any suggestions for a good AND economical rip blade? I have a nice hollow ground blade to cross cut when it absolutely has to look nice, the Ryobi will be good for utility work, but I'd like a good and affordable rip blade. I don't make fine furniture and cannot afford and $80 blade. I'm hoping $40 or less on sale.

[cgallery]

Thanks for the answers. It's the Chinese blade and I'm getting .007 wobble, while me cheapee Skil brand blade is .003.

What method are you using for measuring that wobble? And what instrument? Do you have a dial caliper?

Thanks,
Phil

[gjat]

Using a travel dial indicator. A caliper would be too difficult. A travel dial indicator (less than $10 @ HF) is like a pocket watch with a springy leg sticking out. Mount the dial whilst the leg rests against the blade, the face turns to set it at zero, etc..

[JimD]

I use a Freud 24 tooth rip blade for deep cuts. It makes a BIG difference in the rate of feed with the BT3100. It is about $50 - less if you can find it on sale. You want a flat top grind and few teeth with deep gullets (for dust removal) on a rip blade. The full 1/8 inch cut does not seem to affect the power requirement but if you can find a similar ground thin kerf it might be even better for rate of feed. The resultant cut with my Freud is OK for glueup but takes a bit of sanding if it is a surface that will show. My LU84 combination Freud makes a smoother cut but bogs the saw down some on deep rips. The stock blade that came with my BT3100 (it is a Freud) was a pretty decent rip blade - not as good as my 24 tooth Freud but as good or better than my combination 50 tooth Freud.

Jim

[Knottscott]

I use a Freud 24 tooth rip blade for deep cuts. It makes a BIG difference in the rate of feed with the BT3100. It is about $50 - less if you can find it on sale. You want a flat top grind and few teeth with deep gullets (for dust removal) on a rip blade. The full 1/8 inch cut does not seem to affect the power requirement but if you can find a similar ground thin kerf it might be even better for rate of feed. The resultant cut with my Freud is OK for glueup but takes a bit of sanding if it is a surface that will show. My LU84 combination Freud makes a smoother cut but bogs the saw down some on deep rips. The stock blade that came with my BT3100 (it is a Freud) was a pretty decent rip blade - not as good as my 24 tooth Freud but as good or better than my combination 50 tooth Freud.

Jim

Hi Jim - I had a Freud LM72 also and found it be a very good and efficicient rip blade. It'd probably be amazing on a 3hp cabinet saw, but it did lcause the motor to labor some on the two smaller saws I used it on if I was ripping dense hardwood to full height. I've come across two thin kerf versions of an FTG 24T rip blade that have very similar tooth configurations to the LM72 - the DeWalt DW7124TK, and the Leitz/Irwin 24T TK ripper. I'm really impressed with the way these TK's perform on my 1-3/4hp saw, and the feedrate is noticeably faster....they're wood hogs! I don't know of anyone else that has a 24T FTG TK ripper, but I'm sure there are some...CMT might but I'm not sure.

http://www.epinions.com/content_185638293124

[meika123]

I use a Freud 24 tooth rip blade for deep cuts. It makes a BIG difference in the rate of feed with the BT3100. It is about $50 - less if you can find it on sale. You want a flat top grind and few teeth with deep gullets (for dust removal) on a rip blade. The full 1/8 inch cut does not seem to affect the power requirement but if you can find a similar ground thin kerf it might be even better for rate of feed. The resultant cut with my Freud is OK for glueup but takes a bit of sanding if it is a surface that will show. My LU84 combination Freud makes a smoother cut but bogs the saw down some on deep rips. The stock blade that came with my BT3100 (it is a Freud) was a pretty decent rip blade - not as good as my 24 tooth Freud but as good or better than my combination 50 tooth Freud.

Jim

I, too use the Freud 24 tooth rip blade. Mine eats wood up like a
"supercharged termite."
For general cutting, I use the Irwin Marathon 40 tooth blade. $25.00 ea. and they just keep on cutting.

Dave in NC

[cgallery]

Using a travel dial indicator. A caliper would be too difficult. A travel dial indicator (less than $10 @ HF) is like a pocket watch with a springy leg sticking out. Mount the dial whilst the leg rests against the blade, the face turns to set it at zero, etc..

Sorry, I meant indicator. You mention above that you measured the arbor runout and found none. This is my experience, I wonder if you can lemme know your thoughts.

I had spacer problems, and am now using spacers I purchased from McMaster Carr and also some laser-cut spacers a friend made for me. Actually, the McMaster-Carr spacers work best, some I'm using those.

When I loosen the arbor nut and spin my Forrest Woodworker II blade, I can measure up to about .001 of wobble w/ my digital indicator.

When I tighten the arbor nut and spin the blade + arbor + blade nut + blade washers + spacer(s), I measure about .004 to .005 of wobble.

So do you know what your total wobble is with your best blade? Just kinda curious. Maybe you mentioned this above and I'm just too dense to see it.

Thanks!
Phil

[gjat]

I don't think you will really get a very accurate measure if you spin you blade without it being tightened. You could have a warp near the arbor hole of the blade that is transfered to the perimeter when you tighten.
My best blade (cheapee Skill) is .003 compared to .007 on the Royobi. I had read your earlier posts on the subject. My wobble was much worse than .007 and performed the following steps after talking to a co-worker who used to work in a cabinet shop.
1. Removed arbor nut, washers, blade, and spacers.
2. Polished arbor shaft with 000 steele wool and made sure there was no burrs on the ridge of the arbor (side toward motor that the spacers bump).
3. Using 800 grit wet/dry sand paper (Scary Sharp) glued to glass, lightly polished flat surfaces of spacers and arbor washers.
4. Using a file and 150 grit, removed all burrs/seam on arbor hole of arbor washers.
5. Closely inspected blade for any imperfection of clear coat, anything stuck to the blade. (Know that I'm thinking about it, I'm going to buff it with 000 steel wool and put a light wax on the area that the arbor washers touch it).
6. Waxed the arbor shaft.
7. Cleaned the arbor shaft threads with a tooth pick.
8. Reassembled.

I didn't have a dial indicator at the time, but visually, I could tell that this improved most of the wobble. Meanwhile, I had called Ryobi, and they sent an extra set of spacers. Now that I know more and have used a digital caliper to check the washers and spacers (check at 3-6-9-12 oclock positions) to make sure the two surfaces are co-planer, and using a different blade and a new dial indicator, I have determined it is the blade.

The main factors you need are for the spacers, washers, and blade to move freely on the arbor shaft once you know your shaft is straight. If they move freely, then their co-planer surfaces can mate and position the blade properly. In my case, the arbor washers had very rough arbor holes and the spacers were coated with the black finish. The replacement arbor spacers look like the ones I polished. I'm going to make sure that there's not finish buildup on the Ryobi blade that may make it misalign. If that doesn't resolve it, I'll get a replacement blade.

[cgallery]

I don't think you will really get a very accurate measure if you spin you blade without it being tightened. You could have a warp near the arbor hole of the blade that is transfered to the perimeter when you tighten.
My best blade (cheapee Skill) is .003 compared to .007 on the Royobi. I had read your earlier posts on the subject. My wobble was much worse than .007 and performed the following steps after talking to a co-worker who used to work in a cabinet shop.

So to extrapolate, you're saying you're getting .003 on your cheapee Skill and that is a combination of arbor runout, plus the blade, plus tolerances in the nut, the blade washers, and the spacers? Don't arbors themselves typically have runouts of .0001 for extrememly high-end units to .0004 and even .0005 for machines like the Ryobi? That means, measured at 10", with no other factors, you should be seeing .004 to .005. Add blade wobble and you're at .005 to .006. Another .0001 for the nut, the washers, and the spacer, times 10 (diameter of blade), and you're at .006 to .007, best-case scenario? Or or arbors typically much more accurate than I'm thinking? Maybe I have the # of zeros wrong.

Thanks,
Phil

[gjat]

The dial indicator I have is 100ths of an inch. ".00X"
According to others, they expect around .002 to .003 wobble/deflection/runout with a decent blade on the BT. That's in-line with what my friend said (around .004).

[cgallery]

The dial indicator I have is 100ths of an inch. ".00X"
According to others, they expect around .002 to .003 wobble/deflection/runout with a decent blade on the BT. That's in-line with what my friend said (around .004).

I think you meant to say your dial indicator is good to 1000ths of an inch, right? So I've been able to achieve .004, but didn't note the orientation of the washers, nut, and spacer (I think I'm going to start marking them with a little nail pollish). Now, that is a total of .004, or +/- .002.

Last night I collected a bunch of old Wood, Fine Woodworking, and other magazines. I'm hoping to find a good table saw review where they provide specifications for the Unisaw and maybe some others. So much of what I read online seems contradictory.

Thanks for all the feedback!

Thanks!
Phil

[gjat]

Yes. I meant 1,000's of an inch. Maybe I should be happy with .0007" defelection.