.007" runout - what would you do?

[David Weaver]

Good evening everyone. I just measured the Delta hybrid I got and I have right around 7 thousandths of runout on a forrest WWII with a stabilizer. I thought that was a bit high, so I measured the runout on the hub behind the arbor, and I'm seeing between 0.0015" and 0.002". Somewhere I read that Delta's spec is 0.002", so I don't have any recourse.

Given that, is 0.007" at the teeth (or just before them in terms of the radius) enough to cause any problems with quality of the cut?

Is there anything else I should be doing?

I'm going to have to adjust the trunnion because the back is closer to the miter slot by 0.02", so I'll remeasure the runout after that to see if it has changed.

Any advice?

Thanks in advance.

[Cliff Rohrabacher]

The blade has a 0.007" wobble? It's likely dust unless you whacked the blade or the arbor flange..

[David Weaver]

yes - 0.007" wobble - which given that the flange is just under 0.002 seems about right. I suspect the blade is fine - it's a forrest WWII and it's hardly been used. I'll throw a freud combination blade on the saw just to check it, but based on the runout at the flange, I don't think it'll be a whole lot different.

[Ken Milhinch]

Try measuring the WWII without the stabiliser. If that doesn't improve it, just get on with cuting wood. This is not precision engineering, it's woodwork.

[gary rogers]

With the crazy weather we have here the wood will move more than 0.007 from one day to the next!

[Gary Keedwell]

yes - 0.007" wobble - which given that the flange is just under 0.002 seems about right. I suspect the blade is fine - it's a forrest WWII and it's hardly been used. I'll throw a freud combination blade on the saw just to check it, but based on the runout at the flange, I don't think it'll be a whole lot different.
If it is any consolation....when measuring the side of the blade like that (wobble) you have to cut total in half. .0035 in .....0035 out.
Gary K.

[David Eisan]

Ummm.... How does it cut?

Lee Valley used to sell a product that looked like a blade stiffener but had a number of set screws on the outer hub that you could use to "true up" a blade to 0.000x", but I cannot find it on their web site tonight. Perhaps you might want to look into a similar product.

David.

[David Weaver]

Ummm.... How does it cut?

Lee Valley used to sell a product that looked like a blade stiffener but had a number of set screws on the outer hub that you could use to "true up" a blade to 0.000x", but I cannot find it on their web site tonight. Perhaps you might want to look into a similar product.

David.

I'd imagine it will cut fine - I'm waiting on a 50" Bies fence for it, it'll be a couple of weeks. I just wanted to see if anyone would think that would be a problem. If it does turn out to be (i doubt it will), I'll head to the LV site and see what I can find.

I wanted to make sure that nobody was going to say something like that they had the same thing happen and it resulted in a less than glue-ready edge.

Thanks for the heads up on the LV product.

[Al Willits]

Dave, for some reason if I over tighten the arbor nut on my Hybrid the blade wobbles a bit, maybe check that?

Al

[Gary Keedwell]

Ummm.... How does it cut?

Lee Valley used to sell a product that looked like a blade stiffener but had a number of set screws on the outer hub that you could use to "true up" a blade to 0.000x", but I cannot find it on their web site tonight. Perhaps you might want to look into a similar product.

David.
Now ...that sounds real interesting Dave. If you find one, could you post it?

Gary K.

[Ray Bersch]

Dave;
Does your blade load easily? I found on my new Delta Hybrid that the arbor had some paint or something that made loading the blade difficult and also caused a wobble even after tightening the nut. So I took the blade off, turned on the saw and cleaned it all up with 600 wet dry paper. Now the blade goes on smoothly with no noticeable wobble - I have not put a dial gauge to it but I did make a fresh zero clearance insert and that looks just about perfect so there can't be too much run out - besides, the cut is perfect and that is what I was shooting for anyway.

Ray

[J.R. Rutter]

I think that they are discontinued, but maybe they still have a few around. I have one that I use from time to time. Got it because of a similar problem. It works, but would definitely be best for a dedicated blade. Too fussy to dial in for frequent changes...

[Pete Bradley]

Make sure the arbor's clean as others said. You may be able to get some of the runout out by rotating the blade's position on the arbor.

Pete

[Paul Simmel]

Guys, “runout” is the out-of-roundenss: of the motor shaft. You can't measure for this from the side of a blade.

[glenn bradley]

I use stiffeners on my hybrid. The 'inside' stiffener, of course, places the blade out more than it would be without. I have to be sure the blade seats well as there is a small deviation that I run into that I would not hit without the stiffener (is this making sense?). Anyway, if I forget, the blade will 'pop' on as I tighten it but, I try not to do that. Perhaps you are experiencing a deviation of what I am experiencing(?).

[Loren Hedahl]

I have a Ridgid contractor style saw with about the same amount of runout. I just marked the arbor flange edge with a centerpunch at the point of max. outward deflection. Then before mounting a blade I stick a piece of thin scotch tape on the flange. On a good blade that brings it in to about a thousandth at the tip.

I know it's a 'mickey mouse' solution but it I would rather stick on a piece of tape than sand out a bunch of saw marks.

It also gives me something to complain about.

Loren

[David Weaver]

That's just the kind of suggestion I'm looking for. I won't be cutting too many dadoes, and even if I was, I guess it's not hard to apply tape. It isn't hard for me to find the high spot on the flange, and it won't be hard to mark it with a white marker, so that should be an easy fix.

When I was using a contractor saw, I just never thought to measure it - I threw a blade on and cut with it, and it did fine. It was probably off by as much or more than this one is, and I never had a problem with edge quality or kickback or anything like that.

I come from a group of Central Pennsylvania Germans - we also like having something to complain about. No reason to let things get out of hand with a bunch of positive comments about something.

[Joe Spear]

I have one of those Lee Valley adjuster things. As somebody said, it is best used with a dedicated blade. It has little set screws that push on the blade in several places. It works, but if you change blades, you have to readjust. If anybody is interested in mine, send me a PM.

[Pete Bradley]

Guys, “runout” is the out-of-roundenss: of the motor shaft.
You and the original poster are both right. There's radial runout (what you're talking about) and axial runout (what this thread is about).

Pete

[Mike Goetzke]

Like others have mentioned clean up the arbor flange as you can imagin 0.001" out at 1" radius will magnify to 0.005" at a 5" radius even with a perfectly flat blade. I had a Craftsman hybrid and now have a Uni and could barely see the needle move on the indicator when measuring the face of the arbor flange - probably less than 0.0005".

Try going to WN and search "table saw tune up" for some good info.

Mike

[Brian Dormer]

.007 seems excessive - if not potentially dangerous. That much wobble could cause a heck of a kickback. I used to have a saw that would never adjust closer than about .005-.006 and it kicked ALL THE TIME. My current saw is .002 or less on all the adjustments and it's only kicked once in 2 years of use.

If you are going to use it - put a splitter or riving knife on it. Even an MJ splitter (google it) would provide a margin of safety.

I wonder if the blade or the arbor is the culprit? Try measuring with a different blade? Without the stablilzers?

[David Weaver]

.007 seems excessive - if not potentially dangerous. That much wobble could cause a heck of a kickback. I used to have a saw that would never adjust closer than about .005-.006 and it kicked ALL THE TIME. My current saw is .002 or less on all the adjustments and it's only kicked once in 2 years of use.

If you are going to use it - put a splitter or riving knife on it. Even an MJ splitter (google it) would provide a margin of safety.

I wonder if the blade or the arbor is the culprit? Try measuring with a different blade? Without the stablilzers?

Thanks for the suggestion. The MJ splitter is an interesting little device - I may get one and try it.

I called Delta service, and the phone rep talked to a technician and the technician said 0.0025" is tolerance on the flange, and that the arbor tolerance itself is 0.005" (I haven't measured that), so they don't consider anything I've mentioned thus far to be a problem.

I will be using featherboards, etc. anyway because I work by myself and I've experienced kickback before - standing right in the way of a 3/8th inch thick piece of cherry that was about 12x18. I'm glad it wasn't a bigger piece - it hurt enough!

[Mike Goetzke]

Thanks for the suggestion. The MJ splitter is an interesting little device - I may get one and try it.

I called Delta service, and the phone rep talked to a technician and the technician said 0.0025" is tolerance on the flange, and that the arbor tolerance itself is 0.005" (I haven't measured that), so they don't consider anything I've mentioned thus far to be a problem.


I don't see how 0.0025" on the flange is acceptable. Like I mentioned above this will magnify to almost 0.010" at the tip of a perfectly flat blade.

When you take the flange reading does the pointer gradually move up to the max. reading or does it jump - just thinking there may be a burr on the flange.

Mike

[David Weaver]

I don't see how 0.0025" on the flange is acceptable. Like I mentioned above this will magnify to almost 0.010" at the tip of a perfectly flat blade.

When you take the flange reading does the pointer gradually move up to the max. reading or does it jump - just thinking there may be a burr on the flange.

Mike

It's gradual - like a perfect sine wave oscillation. Thinking about this, I need to check the arbor itself to see how much it moves back and forth - maybe the whole thing is bent slightly. I'll do that tonight. That doesn't offer a lot of promise if the arbor is allowed to move 0.005" itself, though.

I've had some less than great luck lately getting some of the not-primo-priced stuff and finding that I'm getting tools that are in spec, but at the edge of new looser spec. Same thing happened with a Hitachi miter saw - just enough wobble to make it so that the cut of my miters is "OK" or "acceptable", but not dead nutz.

One of my buddies constanly says "there are no bargains in tools - get the best you can afford", and I've still been cheaping it a little, and getting burned each time. I feel like I should've fronted the extra $1500 and gotten a genuine PM 66. :(

[Gary Keedwell]

[scillation.quote=David .

One of my buddies constanly says "there are no bargains in tools - get the best you can afford", and I've still been cheaping it a little, and getting burned each time. I feel like I should've fronted the extra $1500 and gotten a genuine PM 66. :([/quote]

:o Nuff said!
Gary K.

[Mark Engel]

Ok, so we are talking about .007, right.

That is, what, a little less than 1/128 of an inch right?

So a 1/128 of an inch wobble in the blade at 3450 rpm will make the kerf just a little bit (1/128") wider, right?

Get a thin kerf blade. Problem solved. ;)

[Ken Milhinch]

Ok, so we are talking about .007, right.

That is, what, a little less than 1/128 of an inch right?

So a 1/128 of an inch wobble in the blade at 3450 rpm will make the kerf just a little bit (1/128") wider, right?

Get a thin kerf blade. Problem solved. ;)

It's even less, it's approx 1/143 of an inch. Discussions of tolerances to this degree in a material that moves with the weather is, quite frankly ridiculous, and it certainly will not cause kickback.:rolleyes:

[Gary Keedwell]

My understanding is that a wobble in the blade is not one of the causes of kickback. We have a "wobble" dado blade, don't we???
All blades wobble to some degree. Gee, before the modern blade manufacturing techniques...wobble was considered the "nature of the beast" :rolleyes:
Gary K.;)

[Don Brillhart]

Ken hit the nail on the head. Start cutting; sandpaper and scrapers will make your fit seem perfect. This hobby/profession should be fun--not rocket science or precision machine shop work. Check the comment on wood expansion and examine your own furniture for seasonal variations in the dimensions.
There is a lot of nitpicking going on concerning tolerances. Thank God our forefathers were not so predisposed or we would all be sitting on tree stumps debating how accurately we were going to have to cut a board to make a bench!
Don Brillhart, 60 year veteran of this avocation

[Gary Keedwell]

[quote=Don Brillhart;.
There is a lot of nitpicking going on concerning tolerances. Thank God our forefathers were not so predisposed or we would all be sitting on tree stumps debating how accurately we were going to have to cut a board to make a bench!
Don Brillhart, 60 year veteran of this avocation[/quote]

:rolleyes: :rolleyes: :rolleyes: Or cleaning out the horse stalls and hauling in our water from the well outside?;)
Gary K.