Advice before I put on riser block? (Coplanar attempt too...)

Soon I'll install a riser block on my Taiwan 14" BS. Right now it's about 3/8" out of being coplanar. Rather than shim the upper wheel, I'd like to seat the upper arm more correctly so the wheels will be parallel.

Any tips? Caveats?

Thanks, H

Reply to
Hylourgos
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My Jet 14" had pins to align the top and bottom sections that fit into the riser block. I don't think you have much leeway wrt how the riser block seats.

scott

Reply to
Scott Lurndal

With the two dowel pins you won't be doing too much in the way of aligning it other than the way it's already going to align itself. In other words, it will only fit one way.

By the way, up till now has the myth of coplanar presented itself as a problem?

UA100

Reply to
Unisaw A100

Coplanarity(izzat a word?) would more likely be approximated by adding or subtracting washers behind the top wheel rather than frame adjustment. Frame shimming is more useful to bring the guidepost into alignment with the blade along the guidepost's travel, 'iffin it's at all like a Delta. Like UA hunnert' asks, has there been a problem at 3/8ths out? Tom Someday, it'll all be over....

Reply to
Tom

By the way, up till now has the myth of coplanar presented itself as a problem?

UA100

LOL

P.S. You forgot to ask whether he could stand a nickle on the table

Reply to
Tom Kohlman

Yahbut, we all know where that discussion would go. Grandma, Jets, the Sinai, make up and our favorite myth of them all, the lumber car.

UA100

Reply to
Unisaw A100

Hello Mr. 'Saur,

What's to prevent me from drilling new holes for the pins? I've read that some people have done this to their (stock, not riser) units because they weren't aligned correctly in the first place. My riser kit even comes with a nice drill bit for that purpose.

I won't pretend to know whether coplanar wheels make a bit of difference, but theoretically the idea that your two wheels should line up seems just common sense to me. Since I'm messing wth a new riser block anyway, I thought I'd give it a try. If it works out and makes any difference I'll let you know.

H
Reply to
Hylourgos

Mr. Saur was my father.

Absolutely nothing. If you feel you can precisely align four holes in two mating pieces of cast iron then you go girl. Me? I wouldn't touch it with a ten foot (approx. 3 metre David) pole.

You're kidding, right? Isn't this kinda of a sign that the company that made the saw "isn't really too sure but we'll ship along some tooling for you to clean it up in case we didn't get it right"? Not something I'd be putting in the ad copy if you know what I mean.

There is no pretending (or dress up) required with this one. Either the band tracks or it doesn't.

Does the band track correctly?

In theory you are correct but with this one theory isn't needed onna 'count of we have a real world situation that we can draw from. The basis for my argument is, "if the band tracks, you don't have any worries". To be seeing demons where none exist might make for a great hobby but isn't necessary for good fun with wooddorking.

So, we ask again. Does the band track correctly?

Now this is where the choo-choo comes off the tracks. An adjustment made to the riser to compensate for the myth of co-planar might work if your wheels were "slightly" out of alignment. In your case, and if I m'member correctly, your wheels are out 3/8". This would mean that you would have to re-drill the holes 3/8" away from where they presently are. I'm not sure the fixing bolt will fit with that gross of a misalignment, not to mention how screwy it would look. And oh by the way, what if after all of this you've gone an introduced further error? Re-read this last sentence, especially if you have a problem with cause and effect and seeing something to the end injineering wise.

Again, I think you need to determine if the myth of co-planar is a problem first. Tackle that independently of the riser block. If you cannot contain yourself and feel you must screw with the riser it might make more/better sense to shim the riser on one side or the other. This will tip the upper wheel in or out. Now, the only problem with this is you'll now introduce a situation where your upper blade guides are now totally out of alignment and you'll be shimming those.

See where all of this is going? By orbiting around the issue (not looking at/doing something specific with/to the upper wheel) you begin the begets and just create more work for yourself elsewhere. I'd be willing to bet that by the time the whole thing is over you'll be too afraid to operate the saw because it'll be so held together with chewing gum and duct tape that simply turning it on will throw out all alignments.

Hear me now, believe me later.

UA100 (Jr.)

Reply to
Unisaw A100

UA100 responds:

Long and detailed and funny explanation.

Or what you're saying is go with the stock set-up. Put her together and see if she gives you straight cuts (or controllable curves). If that happens, don't screw with it.

Charlie Self "It is not strange... to mistake change for progress." Millard Fillmore

Reply to
Charlie Self

A'yup, herein lies the crux of the biscuit. Trouble is, we can't find out if the band is running correct which is a whole nudder kettle of fish all together.

UA100

Reply to
Unisaw A100

I had some great metal shop teachers. I think I can handle those holes if I want to....

Nope, but the whole kit cost me all of $10 at a hardware store yard sale, so it's possible someone tossed it in for fun. The size and type of bit are curiously appropriate though.

When I DAGNGS on riser blocks and coplanar I read several threads where participants had moved the arm rather than shim because the bearing shaft was not long enough to achieve coplanar by shimming alone. So the process is not uncommon. Among cheaper brands of BSs, the arm is often not accurately mounted in the first place.

Since earlier thread participants mentioned that they had remounted the arm and they didn't mention any big trouble doing it, I am curious about your hesitation: have you tried it?

Well, to be fair, the argument about coplanar wheels and whether they're useful or necessary does not, for its proponents, rely on whether the band tracks without it. Or is that your understanding of their position?

So far. But I've only tried it once, with the blade I got with it, a

3/8" blade. *And* the upper wheel is tilted ALL the way in order to get it to track. Now, my experience with other bandsaws tells me that getting a 1/2 or 3/4 blade to track on this unit might be difficult if a 3/8" tracks only on full tilt. I want to use 1/2" blade mostly, so it looks like shim or move the arm, or see about moving the lower wheel on the shaft. Since I'm installing a riser block, I thought to consider a riser modification first.

Very good point. Accurate placement is assumed. My usual procedure would be a mock up with clamps, spot welds or whatever temporary fix works to see if things will line up conveniently. Tom's point about the guidepost (thanks Tom) and yours here about the other alignment issues are exactly the caveats I'm looking for. Honestly I hadn't considered those issues (although a mock-up would probably have revealed them), so thanks is in order.

OK, I will. Where's the best place to read about the opposing view?

Quite possible, and I appreciate your monitions.

That's a bet you don't want to take.

H, who made more pipe bombs and zip guns before he was 12 than all the unisaws you've ever touched.

Reply to
Hylourgos

Hylourgos states:

City boy, huh?

Charlie Self "It is not strange... to mistake change for progress." Millard Fillmore

Reply to
Charlie Self

My hesitation comes from working with machines and real life usage and a fairly good ability to predict the outcome of a given procedure which for the most part comes true more often than not. When it doesn't I file away what I've learned and use it the next time a same or similar situation arises.

Have I been doing it wrong all of these years?

My "understanding of their position" is,

1) Wheels not coplanar can be the cause of bands not tracking. 2) A band can track on a saw with wheels not coplanar.

Conclusion: Coplanar, it could be the solution as well as not.

That's why I was asking (and secretly wondering why you were skirting around the issue).

Mock ups are good. I wouldn't braze the cast iron for all the obvious reasons.

I couldn't tell you. My position on coplanar is from real world situations and usage (see above) and not blindly following the book writers. I suppose if you really have to see the words in print you could search Google but you'll more than likely only find what I've had to say. Me, not being a book writer, would probably make anything I've said invalid, that is if you only believe what you read in books.

I'm sure your mother is quite proud to see you listing this on your resume.

By the way, before you go Bay Area Dave on us here and start getting your tutu in too much of a bunch, you asked the question, right? Had I known this was all a foregone conclusion on your part, I'd a passed on by. My hopes were to see to it you didn't go and screw up your saw or spend an awful lot of time orbiting the solution. I can see now that your saw is in very capable hands and should you become too frustrated with it you possess the knowledge for the proper means for disposal.

Knock yourself out there now.

UA100, who is usually better with troll detection but thanks you none the less for this chance to recalc the meter...

Reply to
Unisaw A100

You say "can be" not "is". That seems to sum up a lot.

But will twist continuously from its free orientation to its conform-to-the-wheel position. Can you say "fatigue"? Coplanar means no twist.

Mike

Reply to
Michael Daly

[snip]

I can both say and spell "fatigue" (in two languages, even!). But I'm not sure I follow what you mean here. Would you explain things a bit further for those of us in the audience? Thanks.

Reply to
Jeffrey Thunder

you just couldn't help yourself could you?

Try not to fixate on me as much. That way you can spend more time dealing with your other issues, at your next session. I assume you DO see a therapist?

dave

Unisaw A100 wrote:

Reply to
Bay Area Dave

Under tension, the blade is forced to ride tight to the wheel (well, tire actually). Think of two wheels that are coplanar. The blade is straight up and down between the wheels.

Now consider non-coplanar. One wheel is to, say, the left of the other. The blade has to be forced to the left as it leaves one wheel and goes to the other:

|| || || || || // || // || || || ||

coplanar non-coplanar.

Obviously highly exaggerated due to the limits of ASCII art. The non=coplanar puts additional stresses on the blade and the blade is constantly twisting to conform to the tires. You can force it to track, but that doesn't mean you're doing it right.

Mike

Reply to
Michael Daly

I gotta agree with Keeter on this one; coplanar is not all it's cracked up to be. I have a Powermatic which tracks all size blades perfectly and it isn't coplanar, by a small amount when the tension is set. I adjusted it coplanar for grins, and it ran like crap. The mfgr. knows a little bit more about how to design the tool then the net pundits, in this case.

I followed Duginski's instructions, BTW. While I generally liked his Bandsaw book, the coplanar thing is NOT exactly legit.

In theory, it sounds great! In practice, not all saws work well when "adjusted" to coplanar geometry.

If you have had good success with coplanar, I'm not about to disagree with your experience, but for my saw, leaving it stock is best. The good news is I didn't break anything and only wasted an hour or two screwing around with it (mostly to find a suitable shim).

dave

Michael Daly wrote:

Reply to
Bay Area Dave

Would it? You are assuming the blade is going to track on center of the bottom wheel, but what if it does not?

I was at a Scott Phillips demo about bandsaw setup and he dismissed the co-planer thing also. To him, tracking the top wheel and proper tension is needed for true running. Ed

Reply to
Edwin Pawlowski

You didn't read a thing I wrote now, did you Dave?

Mike

Reply to
Michael Daly

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