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Forum topic by Brandon Davis posted 09-09-2014 06:26 PM 1287 views 1 time favorited 13 replies Add to Favorites Watch
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Brandon Davis

8 posts in 2785 days


09-09-2014 06:26 PM

Topic tags/keywords: unisaw re-assembly tablesaw

Q1: a. Can anyone tell me what the “rough distance” of the RH side of the blade to the miter slot should be? b. Should the blade be [roughly] centered between the two miter slots?

NOTE: I’m not asking about the various adjustments you do with alignment gauges and the like to dial a saw in; I have a handle on those procedures. I’m asking about when you’ve had the cast iron top off for some reason or other (like disassembling your saw to replace arbor bearings for example), and you’ve bolted it all back together. And you’ve found that “something’s not right”. :-(

Q2: a. Next. Can-or-should the arbor be adjusted side-to-side on the motor bracket shaft to center the blade (and arbor) to the splitter/blade guard center (or whatever)? b. How?

Q3: a. Can the arbor gear be “off-center” from the worm gear on the height adjustment shaft? b. Would that “off-center” position cause the arbor gears not to mesh very well with the shaft worm gear? c. Could that cause a “clunk” sound? (Not the clunk sound on motor start up. But a clunk sound caused by adjusting the height of the saw.)

Yeah. My Uni’ is seriously messed up right now, and I’m wondering how I should be going about fixing this …including taking the whole thing down to the nubbins to see what’s really going on with it.

...I asked this at another forum, too …but there were no substantive responses (so I condensed it down for asking here).

-- Art


13 replies so far

View Fred Hargis's profile

Fred Hargis

3945 posts in 1959 days


#1 posted 09-09-2014 06:58 PM

The miter slots on mine are 10 11/16” or so apart (CtC), and the blade is about 5 7/8” from the center of the right slot (right tilt saw, 2001 model). So, no the blade is not roughly centered between the slots.

Don’t screw with the arbor, I’m not sure you can adjust it anyway.

2&3 : anything is possible (I guess) but not likely.

Back to the problem, when you re-assembled it everything should have been in about the same position it was when you started. You should be able to slide the top around enough to get it centered on the blade. If not, you have something seriously out of place, and maybe a pic might help with the diagnosis.

Did you keep track of the shims in each corner of the top when you removed it (and put them back in the same spot)? If not, you may have another problem.

-- Our village hasn't lost it's idiot, he was elected to congress.

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Brandon Davis

8 posts in 2785 days


#2 posted 09-09-2014 07:35 PM

Thanks so much. At that “other forum” I had a pretty comprehensive explanation, but briefly:

I bought this used in Sac’ about 7-8 years ago or so. It was a C/L “find/good deal” that the seller told me he had purchased days before at an estate sale (for a retired high school shop teacher). It was in pretty good shape, overall (though missing a fence). It ran, at least.

It sat has since sat unused (first in CA, and then in WA after we moved) until this past weekend. I finally have some time for diving into the saw, which I need for various projects.

My suspicion after this past weekend (from “the little things” I’m finding) is that the owner may have done some work, or started to, or something …and passed away before he was able to put it back together correctly. Dunno. Just guessing. Seems likely.

I’ve never seen “shims” in any parts descriptions where the top table bolts to the case though (probably haven’t looked closely enough). Is that what you’re talking about (or did I mis-read there)?

I did kind of suspicion it might be missing a shim (or whatever) on the [motor] shaft that the arbor swings from.

Because there is some barely visible side-to-side play on that shaft (not a lot, but I haven’t tried anything other than eye-balling it so far). When I replaced the blade, and the slot in the zero insert was shifted to the right, I called it quits until I had some advice.

But I don’t see how a missing shim on the tabletop would cause the visible (and hear-able) slop in the rack-to-worm gears (and they do not look or feel worn at all …the Uni’ seems to have not been used all that much, really: but what do I know lol).

I could see a missing shim on the main yoke casting shaft (that’s what I’m calling it: that big central piece that the arbor assembly and the motor hangs from) could cause a misalignment. I was hoping to hear from someone who might have come across this before.

I don’t know how to check if the arbor gears are properly centered on the height adjustment shaft worm gear.

From what you’ve said, though, I’m going to try moving the top (to the left), starting from your measurements.

When I was aligning it “to the nines”, I certainly could have shifted the top in relation to the arbor. (I didn’t ponder that happening: live and learn, sigh.)

...I’m trying to avoid a tear down. But I will if I have’ta.

Actually, I want to shift the position of the individual belts anyways, so I’ll probably take the top off regardless. The belts are not worn (nor in any kind of bad shape), but they seem to have taken a “set” after all these years. Might as well make it worth my while.

Thanks again.

-- Art

View Fred Hargis's profile

Fred Hargis

3945 posts in 1959 days


#3 posted 09-09-2014 08:11 PM

Those shims would not (probably ) have been listed on any parts list, since they are installed to get the top on a level plane to the arbor every one might (will) have been a different thickness. But I don’t think those shims would be related in any way to your current problem, they just may contribute another one. Also, the belts can be shifted (and replaced) without removing the top; not trying to talk you out of doing that but don’t make more work than you need to until the saw is at least close to be in working order. To be honest, if this turns out to be one of those ‘worst case” scenarios, you might consider joining OWWM, and asking for help there. they have some real Unisaw experts that have torn them down to the last nut/bolt and you may get more detailed help there. there’s also a guy here (toolie) who found a great resource for Unisaw help, and I can’t think of the name…but if he sees this post I’m sure he’ll chime in. Others here have rebuilt them as well, so you may have to wait for them to chime in.

-- Our village hasn't lost it's idiot, he was elected to congress.

View Brandon Davis's profile

Brandon Davis

8 posts in 2785 days


#4 posted 09-09-2014 08:25 PM

Thanks Fred!

If I don’t have to take the top off to move the belts, or period (unless I absolutely have to), I’ll just re-orient to your numbers, and try a little harder to lift up the motor to get to the belts.

...I know I read that the belts should be run a little loose, too. Do you happen to know where that adjustment is made off-hand?

...I should be able to work on it again later this afternoon. I’ll follow up after.

-- Art

View Brandon Davis's profile

Brandon Davis

8 posts in 2785 days


#5 posted 09-09-2014 09:01 PM

Fred: You were the inspiration enough for me to find a clue to my “how to center the arbor on the shaft” dilemma.

I did a search on how to adjust the belts to loosen them, and tucked away in the directions was ”Remove the bolt that tightens the bracket to the arbor support. Note how much of the support shaft is protruding out of the bracket so that you can re-install it back to the original position. You may want to mark its location.”

Yeah, well that ship had already sailed sigh.

So the top is coming off after all.

In case anyone down the road comes across this post while researching the problem, here’s a link to the webpage on adjusting the belts (AND why you should have marked the arbor location on that support shaft) ...

The Saw Center: ”Removing the table

...now I get to figure out how to center the thing.

This is going to be a two-beer afternoon I think.

-- Art

View Fred Hargis's profile

Fred Hargis

3945 posts in 1959 days


#6 posted 09-09-2014 09:26 PM

The Saw Center is the place I mentioned and couldn’t remember the name. They are a treasure trove of knowledge. Good luck with your effort. (BTW: only 2?)

-- Our village hasn't lost it's idiot, he was elected to congress.

View Brandon Davis's profile

Brandon Davis

8 posts in 2785 days


#7 posted 09-09-2014 10:00 PM



The Saw Center is the place I mentioned and couldn t remember the name. They are a treasure trove of knowledge. Good luck with your effort. (BTW: only 2?)

- Fred Hargis


Two and I’ll be more’n halfway to la-la land. I’m pretty much a light-weight in the brewski’s department lol.

Thanks again.

...I’ll followup with before and after pix. Well, so long as I’m successful lol.

-- Art

View toolie's profile

toolie

2025 posts in 2094 days


#8 posted 09-11-2014 01:09 AM

This is going to be a two-beer afternoon I think.

if there are two things that usually don;t go together well it’s beer and power tools. or is that the reason for the sawstop?

-- there's a solution to every problem.......you just have to be willing to find it.

View Nubsnstubs's profile

Nubsnstubs

826 posts in 1195 days


#9 posted 09-11-2014 02:27 AM

Brandon, if you can do this in two beers, do it. It took me 3 days.
I replaced my bearings about 8 years ago, and shhhh, don’t tell anyone, I broke the arbor housing removing the bearings. I had it welded as I couldn’t find any availible I could afford, and took it to a machine shop to check the alignment. Almost perfect, so I put it back in, replaced the top. Shhh, I didn’t really pay any attention to the placecment of the blade and top. Years before the repair, I scribed a line indicating the right edge of the blade, and when I cranked the top down, tightened all the bolts and nuts for the fence, I raised the blade to find out it was exactly 1/16” short of being on the money. I can live with that mistake, but I do have a slight issue with the heigth adjustment.

Before the bearing replacement, when I lowered the blade to full stop, it stopped. The handle wouldn’t move either way unless you gave it a nudge. It raises without issue, but now when lowering, it dosen’t come to that full stop like before. I think the blade stops too early, and the handle will move about 1” or more, not like that dead stop before. Also, I don’t remember the retracted blade being as close to the top surface as it is now.. When replacing the top, I believe the worm screw needs to be in a particular position to have it like the factory set up.

I didn’t see any shims either. If the top is ground properly, and the other components are milled to specs, there would be no need for shims. Even though I’m not the first owner, the saw was only about a year old when I bought it from a friend who decided to quit woodworking. I got it in ‘92.
I know what the problems are. They don’t effect anything other than my pride when I think about it. I let the bearing replacement kick my butt. When I do attempt to sell it, I’m hoping I don’t forget to indicate those little problems. Memory’s going fast. ............... ???(in Tucson)

-- Jerry (in Tucson)

View Aj2's profile

Aj2

692 posts in 1263 days


#10 posted 09-11-2014 04:39 AM

You will find out soon enough if you are missing the shims.When you tilt the blade to 45 and make a rip or cross cut .Be careful if it’s way out the saw blade will be cutting skew.If it’s missing shims.Aj

View Brandon Davis's profile

Brandon Davis

8 posts in 2785 days


#11 posted 09-11-2014 09:44 AM



This is going to be a two-beer afternoon I think.

If there are two things that usually don’t go together well it’s beer and power tools. Or is that the reason for the Sawstop?

- toolie

That’s actually a common misunderstanding in woodworking circles.

Mixing beer and power tools isn’t necessarily a problem.

Its mixing beer and cords that is the real problem.

Cords can be tricky things. Especially around a beer (or two).

Bot so long as you keep those darn power cords away from any wall sockets during times contiguous to your sipping’ on a tall cold one and for a bit after, you’ll be just fine. You can even put the beer on the power tool (with a suitable coaster, natch’) and you’ll hardly ever suffer ill consequences.

Actually, I’d suggest following that rule with a Sawstop’s cord too.

YMMV, but that works for me.

-- Art

View Fred Hargis's profile

Fred Hargis

3945 posts in 1959 days


#12 posted 09-11-2014 11:42 AM

So where are you on the total job? Get ‘er straightened out yet?

-- Our village hasn't lost it's idiot, he was elected to congress.

View Brandon Davis's profile

Brandon Davis

8 posts in 2785 days


#13 posted 09-11-2014 05:43 PM



So where are you on the total job? Get er straightened out yet?

- Fred Hargis


Well. I thought I was done lol.

Until I read Nubsnstubs and AJ2’s replies.

Now I’m thinking I better go back and recheck.

I have pretty much answered my own Q3 with a “Yes” to each part. 3a: An arbor gear can be off-center from the height adjustment shaft’s worm gear. 3b: Which off-center position will cause slop in the gears. 3c: Which will cause a clunk sound.

Q2 gets a yes, too, along with a non-binary how-to. 2a: The arbor can fairly easily – and without taking off the table top – be moved no mean distance (as much as +/- 1/4”) on the motor bracket shaft. 2b: To move the arbor, you need to
1) take off the inner blade guard,
2) adjust the arbor angle to around 30 degrees
3) loosen the arbor clamp bolt
4) adjust the arbor angle back to 90 degrees
5) raise the motor to full up
6) prop the motor in that full up position (a scrap 4×4 cut to length works nicely)
7) loosen the motor lock bolt
8) lower the height from full up, causing pressure to be removed from the motor bracket shaft
9) carefully and vigorously “jiggle” the arbor casting while tugging on it in the desired direction

2b-9 is where things get tricky. In my case, I have a Delta splitter which should presumably be centered on the blade. So I would jiggle a bit. Mount a blade. Place straight-edges on either side of the splitter, and check how centered the blade was. Lather, rinse, repeat.

Eventually I got to the point where one straight edge was flush to the splitter, and kissing the blade, and the other straight edge was kissing the blade and a half-hair more-n a whisker parallel to the other side of the splitter.

I called that distance good. And – after adjusting the belt tension to a moderate slack level – tightened the motor bracket lock bolt up and the arbor clamp bolt down (taking care not to over-tighten the clamp bolt, as I had read that you could bust the arbor clamp if you got too vigorous with it).

At which point I measured the arbor play (it was +/- .0005: pleasant surprise, that), and loosened up the table top bolts and aligned the miter slots to the never used 1/8” Delta blade (play there was +/- .002 when finished).

I also went back through aligning the fence to the miter slots, and got that down to something reasonable (given that it’s a Ridgid fence that is going to be changed out when finances permit, “reasonable” was the best I was hoping for).

I noted from the fence bar ruler I had been over 3/16” off center.

I finished up by replacing the inner blade guard.

There wasn’t time for test cuts. And I was mindful of how tricky power cords could be in the proximity of a glass of beer, so I called it a night.

...and thought I was close to done.

Until I read the additional replies.

Gee. Thanks guys!

Now I’m thinking I better measure for the miter being off kilter. And – having also noted that the bottom height stop was a bit mushy, I’m wondering if my “half-a-hair past a whisker” measurement shouldn’t be tightened up too.

:-(

So that’s the current status.

I will follow up after I get some time to get back to the project (probably Saturday at this point, as work has definitely intruded on my shop “quality time”).

And that’s where it stands for now, Fred.

-- Art

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