# Jerry's latest Accuracy Test....



## Jerry Bowen (Jun 25, 2011)

Some time back I was writing on this forum about the problem that I was having cutting accurate 30 degree cuts to make a six sided hexagon that would be used to make a bowl on my brother's lathe in Alaska. When I first attempted the project I had a ripping blade on my saw, a Freud Fusion Thin Kerf blade in case anybody would like to know. I had no luck with my 30 degree cuts being close enough to get the six parts together with no visible gaps. I didn't know if it was my miter gauge which is, by the way an Incra V27 tool. In fact I went so far to purchase an Osborne gauge which is probably as accurate as the Incra but certainly no more so.

So in my frustration I switched to a Forrest cross cut blade with a stabilizer and every thing went together perfectly, no gaps, perfect fit, I was a happy camper.

This morning I decided to try some tests, I began with the Freud ripping blade, I tried it with and without the stablizer. I experiment with the pressure that I applied to the stop on the Incra Express sled, I tried using the hold down and tried without the hold down. No matter what I did there was error of as much .020" in the length of the cuts. By the way I was using crown molding for my test meaterial as I have almost an unlimited supply of the stuff that I will never use for what it was made for. As you know, it is made f soft wood, I wondered if hard wood would cut more consistantly, but have not tried that.

The next thing I did was to put the Forrest Cross Cut Blade on with the stabilizer. I made eight cuts with that blade, no hold downs, and the six cuts varied by .002" which is at this point anyway what I was hoping for. I am starting to understand better the value of both the ripping blade and cross cut blade. They both do great jobs when used for the purpose that they were made for. Isn't that a strange discovery.... 

Now I am certain that this is no revelation to the woodworkers that have been around this stuff for any length of time, but maybe it will be of value to the new guys on the block like myself. To me anyway, these things are imortant for me to know. Years ago when shooting in benchrest compition I learned that checking the little things and using the knowledge that I learned made the difference between a good day's shooting and a day that was not so good. Justf for the heck of it I will tell you about such a thing that a friend told me to try, it is not something that I came up with on my own. When I starting with the serious shooters I did reasonable well at the 100 yard stage of a match, but when we would go to the 200 yard stage my results were less that outstanding. This problem went on for a couple of years until one day at a match one of my friends came to me in private and said "Jerry, I have watched you struggling at 200 yards and I know that you are a better shooter than what you are doing". This man was one of the better long range shooters in the business, I mean, he was one of the best winning many matches due to his ability to shoot at 200 and 300 yards. Anyway he told me to, when going from 100 to 200 yards to seat my bullet out further out by .015" and to go up on my powder charge by half a grain. This made a difference and one day after that I set a range record at 200 yards by putting five shots into .257". I learned the value of the little things when I was shooting and is probably why I am such a stickler about them now that my interest has turned to wood working. The things that I am interested in are not of much interest to the average wood work, or so it seems to me after being on this forum, much like shooting, the vast majority of shooter that shoot for fun are very happy with their rifle if they can put five shots into three or four inches at 200 yards, after all, that level of accuracy is perfectly good enough to kill a dear and most big game, as is the average accuracy of most tools that most of us use to turn out very nice well finished projects, so forgive me when I talk about nittly gritty levels of accuracy, it's just in my blood I guress.

Anyway, I suspect that I bore most of the people to death that read my threads, but if a coupld or so of you care about such things or at least like to read about what I am doing O.K., then that's great. By the way, someday I will post some photos of a project for you to look at. 

Jerry Bowen
Colorado City, TX


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## Gene Howe (Jul 10, 2007)

You don't bore me, Jerry. I, to am CDO (Like OCD but, with the letters in the correct order) when it comes to accuracy. And it bugs the HE!! out of me when I can't get the tool to do what I want. 
You provided a very informative set of test results. Thank you.


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## MAFoElffen (Jun 8, 2012)

Jerry Bowen said:


> Some time back I was writing on this forum about the problem that I was having cutting accurate 30 degree cuts to make a six sided hexagon that would be used to make a bowl on my brother's lathe in Alaska. When I first attempted the project I had a ripping blade on my saw, a Freud Fusion Thin Kerf blade in case anybody would like to know. I had no luck with my 30 degree cuts being close enough to get the six parts together with no visible gaps. I didn't know if it was my miter gauge which is, by the way an Incra V27 tool. In fact I went so far to purchase an Osborne gauge which is probably as accurate as the Incra but certainly no more so.
> 
> So in my frustration I switched to a Forrest cross cut blade with a stabilizer and every thing went together perfectly, no gaps, perfect fit, I was a happy camper.
> 
> ...


Jerry-

Do you have any other blades to test with?

There's some big differences in your test base. I think those differences are throwing your results off and giving you a false positive to your conclusion:

Frued Premier Fusion Thin-Kerf Rip Blade. 10" 5/8" 40T Hi-ATB. Kerf .091, plate thickness .071. With and without the stabilizer (but still a thin kerf blade).

Forrest Woodworker II Crosscut blade (WW10407125) 10" 5/8" 40T ATB. Kerf 0.125 (1/8"), plate thickness 0.125 (1/8")... tested with a pair of 1/8" stabilizers... 3/8" thick for the diameter of the stabilizers (with the blade).

Seems to me that the difference is not the tooth design (Angle of tooth and size of gulley), but of the stability of the blade plate. Other factors could also be whether a plate from one manufacturer to another is "tensioned" to try to prevent blade flex. 

What is that? That is when a disk spins (and introduce heat expansion) and one side tries to expand more than the other side can, resulting in a dished plate while spinning at speed. They tension or hammer the disk plate to straighten it and to introduce internal stress to try to prevent cupping of the plate.
http://www.google.com/url?sa=t&rct=...rYHABA&usg=AFQjCNGw-za3bw9qACWHl2619kaRvwD5SA(Please read the preview of page 1 for a good summary and intro)

You might now see that introducing a blade stabilizer, while helping the plate with balance and harmonics, also helps try to prevent cupping by sandwiching the plate between the halves, thus thickening the plate.

Basically, I feel a fairer a test for you would be to test *same thickness* plates of both rip and crosscut configs, without the stabilizer "with all" and/or with the stabilizer "for all". Otherwise aren't you comparing apples to oranges? Maybe thrown in an Irwin 10" 24T rip, a Tenryu 60T PR-25560D or something along the lines of a 36T glueline. Maybe an old 40T HSS (pre-carbide) crosscut or combo? (cause I think I have some old-school hss blades that get me better results than your Frued did...)

Help one, but not the other (thin-kerf vs not)? Isn't that like asking 2 evenly "physically" matched teen boys to get from point A to B (racing), but give one a new Ferrari and the other a 15 yer old Yugo? External advantage. Wait, I guess that example all depends on the fuel stops, but anyways... Does that make sense? The test base should be comparing similar things.

On a side note- Talked with someone the other night who owns the same model of the sliding table cabinet saw I'm buying. He got the opposite results with the Forrest on his saw and was very let down by those results. Told me not to use that particular blade with that saw. (One of the "very few" bad things he could remotely come up with concerning that saw.) I don't know. Maybe some blades got past by QA and I have to go off my own experiences sometimes, but that will still be a mental note lingering in the back of my mind.

Keep up the info. I enjoy reading it.


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## DaninVan (Jan 1, 2012)

*Weird*

Mike; that anecdote about the Forrest blade on your soon-to-be-new saw sounds very suspicious(?). If his saw is running true, why should an otherwise perfect blade misbehave? Either there's an issue with that particular saw or that particular blade, and he really should get to the bottom of the problem. I'm pretty sure neither manufacture wants to have their reputation sullied and would be very pleased to get to the bottom of it. 
It could be something as simple as his saw not being firmly mounted and vibration is resulting?
Very curious.


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## MAFoElffen (Jun 8, 2012)

DaninVan said:


> Mike; that anecdote about the Forrest blade on your soon-to-be-new saw sounds very suspicious(?). If his saw is running true, why should an otherwise perfect blade misbehave? Either there's an issue with that particular saw or that particular blade, and he really should get to the bottom of the problem. I'm pretty sure neither manufacture wants to have their reputation sullied and would be very pleased to get to the bottom of it.
> It could be something as simple as his saw not being firmly mounted and vibration is resulting?
> Very curious.


Dan-

I'm thinking same in that something may be "loose" in Jerry's setup that might be causing that. Doesn't seem "consistent" somewhere. 

I'm curious alsoon the Forrest blades results with that person. That's why I commented that that's why I would have to experience that one in person. But that also brings note to Jerry's Frued Premier Fusion. I read great reviews on that compared against the Forrest in tests.

Vibration or not firmly mounted? I don't think so. Laguna TSS (european sliding table cabinet saw with scoring). Over 1000 pounds. You would think less vibration than my 40 yo old cabinet saw. Crosscut fence on the sliding table using fence stops and a material hold-down. Seems pretty consistent base for what should have been quality and consistency. Very curious results though. I'll have to see.

Since I don't have a lot of time with these new rotating shifts and long hours, I was thinking maybe just doing a similar test with my two 5 gallon buckets full of blades. Maybe on my jobsite saw and the cabinet saw? (I rip glue lines on that jobsite saw.)...Just to get a dose of saw dust in, in (now) limited time.


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## Jerry Bowen (Jun 25, 2011)

Well H, I will try for the fourth time to write this post, I tried three times earlier and all three of them were lost just about the time I got to the end and as you know by now, my posts are never short.

The reason that I only tested my two blades is that I am currently using using these two blades on my table saw. To date I do not have 5 gallon buckets full of blades. I do have another Forrest cross cut blade on my radial arm saw and two thin kerf blades that need sharpening, they are the $40 Freud blades, they didn't last very long. The Fusion blade used in the recent tests is the $80 blade and is supposed to be a better blade of course.

The real purpose of the test was to see which blade I need to use when consistant cuts are a must, such as when attempting to cut six part hexegons with tight and gapless joints.

I came to the conclusion that my Forrest blade does a pretty good job and that the Freud blade will not work for that application. So, for my purposes, the test told me what I wanted to know. I should say that I confirmed what thougt was correct.

As to the statement that something might have been loose when making the cuts. I don't think so. The blades were pulled up very tight when installing them and the sled is almost foolproof in that it rights in the miter slots. The fact that my last test was so close to perfect could not have been possible if anything was loose, or I should say, I think so.

In regard to the new saw and guy wanted a new saw, I am looking at a Saw Stop, the professional cabinet model. I say looking, the boss is bucking, can't really blame her in that I spent $3,000 earlier this year on a new Grizzly band saw and a Grizzly jointer. 

Anyway, let me see if I can submit this without losing it.

Jerry


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## Cherryville Chuck (Sep 28, 2010)

Jerry, a few years ago I wanted to make a picture frame out of some red oak. I went and bought a $60 Delta (who knows what it really was) blade that was supposed to be just for chop saws. I made a couple cuts and tried matching them up and the joint was horrible. I had a look at the cut and noticed that the blade seemed to be bouncing around on the grain. I got some blade stabilizers from Lee Valley and that solved the problem. Since then I am a big believer in them when you don't have to have 3" of cut and need accuracy. Even Forrest recommends them.


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## Jerry Bowen (Jun 25, 2011)

Cherryville Chuck said:


> Jerry, a few years ago I wanted to make a picture frame out of some red oak. I went and bought a $60 Delta (who knows what it really was) blade that was supposed to be just for chop saws. I made a couple cuts and tried matching them up and the joint was horrible. I had a look at the cut and noticed that thie blade seemed to be bouncing around on the grain. I got some blade stabilizers from Lee Valley and that solved the problem. Since then I am a big believer in them when you don't have to have 3" of cut and need accuracy. Even Forrest recommends them.
> 
> 
> Reply to the above post:
> ...


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## Big Steve (Feb 12, 2012)

Jerry, I like your posts. Your "experiment" seems flawed. It confirmed what you expected, which is always suspect I fear. If the outcome proves to do what you want then all is good.

But if variation pops up, think about the fact that you had two different blade/tooth designs, two different blade thicknesses, and with/without stabilizers. I don't think you tested every combinations of those parameters.


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## MAFoElffen (Jun 8, 2012)

Jerry Bowen said:


> I only have one stabilizer and never thought of using two of them as suggested by another member in an earlier post. The one stabilzer didn't make much difference on the Freud blade but for what it's worth, usually, about four out of six cuts


Jerry-

??? All the blade stabilizers I have here (4 sets, two 3" pairs, two 5" pairs) are matched pairs of balanced disks that you put one on each side of the blade. 
























Like I explained briefly in that post:

The extra weight acts as a flywheel type of weight to help balance a blade and helps with harmonics. Stiffens the blade as the blade is sandwiched between it out to the diameter of the diameter of the stabilizers, so acts as a blade stiffener.

You do lose some depth of cut, but at max depth of cut, you usually aren't looking at a finish cut anyways.


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## Harrison67 (May 30, 2012)

Jerry, something I found out is that Shopsmith makes a hollow ground blade for ultra smooth, highly accurate cuts, especially on stock under 1.5 thick.

This blade is so solid, there is no need for stabilizers at all...and I can consistently make cuts within .001 tolerance. Experimented on several pieces of Birds Eye Maple, Walnut, Cherry, White oak, with zero variance.

This blade would be fantastic for cutting the segmented pieces for glue up turnings.

Last year, I found 2 of those blades for $16.00 on Ebay. You don't see them very often.

I haven't checked whether Shopsmith still makes, or sells them. The seller said they were still sharp, and he wasn't kidding.

If they still sell them, I bet they're a lot more than what I paid.


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## Jerry Bowen (Jun 25, 2011)

Big Steve said:


> Jerry, I like your posts. Your "experiment" seems flawed. It confirmed what you expected, which is always suspect I fear. If the outcome proves to do what you want then all is good.
> 
> But if variation pops up, think about the fact that you had two different blade/tooth designs, two different blade thicknesses, and with/without stabilizers. I don't think you tested every combinations of those parameters.


Steve, I tried both blades with and without the stabilizer installed, all I wanted to find out is which one of the two blades would make consistant cross cuts and the only one of the two was the Forrest Cross cut blade with only .002" of variation. My tests, in my opinion were satisfactory for what I needed to know. Can you tell me how much variation you get when making several cross cuts with the set that you use. I was cutting three inch lenghs of soft crown molding as I said earlier in this thread. I don't understand why this is so difficult for people to understand, the only thing I wanted to know is which one of my two blades cut the most consistant cross cuts and I found which one would do that, what is so difficult about that? Scratching my head over my inability to communicate such a simple matter.

Jerry


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## Jerry Bowen (Jun 25, 2011)

Harrison67 said:


> Jerry, something I found out is that Shopsmith makes a hollow ground blade for ultra smooth, highly accurate cuts, especially on stock under 1.5 thick.
> 
> This blade is so solid, there is no need for stabilizers at all...and I can consistently make cuts within .001 tolerance. Experimented on several pieces of Birds Eye Maple, Walnut, Cherry, White oak, with zero variance.
> 
> ...




Harrison, thanks for the tip, i will sure be looking into that, I'll try to let uyou know what I find out.

Jerry


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## MAFoElffen (Jun 8, 2012)

Harrison67 said:


> Jerry, something I found out is that Shopsmith makes a hollow ground blade for ultra smooth, highly accurate cuts, especially on stock under 1.5 thick.
> 
> This blade is so solid, there is no need for stabilizers at all...and I can consistently make cuts within .001 tolerance. Experimented on several pieces of Birds Eye Maple, Walnut, Cherry, White oak, with zero variance.
> 
> ...


Shopsmith still sells new blades as accessories for the Shopsmith, but don't they have sort of a niche there. The only Shopsmith branded blades I can find now, is for their 1-1/4" arbors. Did they used to sell 10" blades for their 5/8" arbors (different accessory arbor adapter)?: 

Extract from Ebay- <<Shopsmith 10” hollow ground saw blade, 80T, *1 ¼” arbor bore* in the original packaging – part number 505547>>

Shopsmith - Accessory Catalog - 10 inch Carbide-Tipped Saw Blades
Shopsmith - Accessory Catalog - MARK V Accesories - MARK V Saw Blade Arbors


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## DaninVan (Jan 1, 2012)

In addition, Mike, using _only_ one introduces a huge amount of stress on the blade. It in effect deforms the blade in the direction away from the solo stabilizer. I'm surprised it doesn't actually make a strange sound when operating(?), not to mention possibly leaving burn marks.


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## Dmeadows (Jun 28, 2011)

DaninVan said:


> In addition, Mike, using _only_ one introduces a huge amount of stress on the blade. It in effect deforms the blade in the direction away from the solo stabilizer. I'm surprised it doesn't actually make a strange sound when operating(?), not to mention possibly leaving burn marks.


Probably any stabilizer will affect the way the anti-vibration cutouts in the blade work! However I have ran one stabilizer on the nut side of the blade for many years, with no ill effects that I can notice. I get some stabilization from it , probably not as much as if I used both. It also doesn't change my fence calibration that way!

Jerry, I can't understand why you would expect crosscuts with any ripping blade to be as good as those made with a top of the line crosscut blade?


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## Cherryville Chuck (Sep 28, 2010)

I prefer to use them as a pair and that was the way that Lee Valley sold them. I know that Forrest only recommended using one which seems odd to me but they surely know more about it than I do. From my experience they work really well as a pair so I will likely continue using them that way. They do knock the fence scale off but I rarely use them for ripping since I get a good enough job without them for that. I also usually get a good enough job when crosscutting 90 degrees. It's when I cut miters that I find I need them.

The problem with mitering is that when you are going across at an angle you are crossing through soft early wood and hard late wood and back again which offers different resistances to the blade and tend to cause it to wander without the stabilizers.


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## bobj3 (Jan 17, 2006)

No one said that you need to use a 10" blade in a table saw,the bigger blade the more the "wander " I use a 6 1/2" carb. tip blade all the time,most of the time I'm cutting 3/4" thick stock without stabilizers  and it's always dead on..if I want it to be a real dead on cut I put sand paper the saw blade (on both sides of the blade) no clean up needed after the cut.

===


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## BillReed1 (Aug 12, 2005)

Keep up the good work Jerry! I enjoy your posts and attempts at accuracy. I sometimes have some of the same agonizing problems. Whatever you do to get the job done, and the results you are looking for works for me.


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## DaninVan (Jan 1, 2012)

?...If I put a stabilizer on the inside, against the machined face of the arbor, then my splitter/anti-kickback/guard is out of alignment with the blade. No thanks. I hate the damn thing _as_ it is.


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## Jerry Bowen (Jun 25, 2011)

Dmeadows said:


> Probably any stabilizer will affect the way the anti-vibration cutouts in the blade work! However I have ran one stabilizer on the nut side of the blade for many years, with no ill effects that I can notice. I get some stabilization from it , probably not as much as if I used both. It also doesn't change my fence calibration that way!
> 
> Jerry, I can't understand why you would expect crosscuts with any ripping blade to be as good as those made with a top of the line crosscut blade?


Duane, I didn't expect the rip blade to cross cut like a cross cut blade, just wanted to see how much difference there is between the two blades. I got the hint when I was cutting 30 degree angles to form a hexagon. There sure has been a lot of confustion about this thread, almost wish that I had never started it. Will really give some serious thought about starting another thread.

Jerry


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## Jerry Bowen (Jun 25, 2011)

bobj3 said:


> No one said that you need to use a 10" blade in a table saw,the bigger blade the more the "wander " I use a 6 1/2" carb. tip blade all the time,most of the time I'm cutting 3/4" thick stock without stabilizers  and it's always dead on..if I want it to be a real dead on cut I put sand paper the saw blade (on both sides of the blade) no clean up needed after the cut.
> 
> ===



Bob, that makes a lot of sense, I will give it a try. Jerry


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## Dmeadows (Jun 28, 2011)

DaninVan said:


> ?...If I put a stabilizer on the inside, against the machined face of the arbor, then my splitter/anti-kickback/guard is out of alignment with the blade. No thanks. I hate the damn thing _as_ it is.


That is another good point, Dan. I also kind of agree with Bob unless it's a thin kerf blade. I like the advantage of .125 kerf for many things... .092 or something odd is just harder to allow for sometimes.


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## Sawdust Don (Nov 1, 2012)

I will second what bobj3 said,

I often find that a Diablo 8 1/2" 60 tooth will cut smoother then a Diablo 10" 80 tooth blade.
The $10 7 1/4" blades work pretty good for many jobs, like salvage wood for example, and to save wear and tear on that $100 plus Forrest blade.
I dont care much for the thin kerf 10" blades, I tend to think they are more for low hp saws.


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## Harrison67 (May 30, 2012)

bobj3 said:


> No one said that you need to use a 10" blade in a table saw,the bigger blade the more the "wander " I use a 6 1/2" carb. tip blade all the time,most of the time I'm cutting 3/4" thick stock without stabilizers  and it's always dead on..if I want it to be a real dead on cut I put sand paper the saw blade (on both sides of the blade) no clean up needed after the cut.
> 
> ===




I've also used that method for very accurate, glass smooth, cuts.:yes4:


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## bobj3 (Jan 17, 2006)

Just some snapshots

==


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