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Bandsaw blade wobble

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boardgamer

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After many years of just using the thing, I'm trying to fettle my bandsaw (Startrite 352) properly. To make sure I have the best chance, I've installed a brand new blade. With all the guides well out of the way, I notice that the blade (wheel turned by hand) has a twist/wobble. If I look at the blade from directly in front, sometimes it is dead straight, other times the back of the blade is twisted slightly sideways (I guess about 1mm). Tension doesn't affect it one way or the other.

Is this normal, or should the blade run dead square front-back at all times?
 

Ttrees

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Did you try cleaning the tires, scraping them with a blunt chisel gently and carefully?
Look up Bill Carter blunt chisel technique.
Make sure your belt is not knackered, you can buy belts cheaply in lawnmower places and such for a fraction of a tool brand one, bring the belt with you.
If they're cleaned allready, I would guess they need dressing.
Do not try this untill you have ruled the underneath guidelines first.

Here is what I've had to do a few times, not got my machine quite right yet as the lower tire had a huge lump taken out from it, which I tried to smooth off by crowning, which wasn't a good idea.
I had nothing to lose though ( I thought), and your machine sounds like it works somewhat....
Thats probably the difference!

I took it back to flatish but its still not right...
If I had filled the missing lump, and dressed it flat it would have been sorted.
I ended up buying a new tire but yet to fit it.
You can get good results doing this method, but know first what profile the tires are meant to have.
From this
DSCN1700.JPG

To this, still not there yet but you get the point, my tires are flat.
Checking for uniform tire height.JPG

Doing this method made my saw a lot better, as the blade was all over the place before.
SAM_1151.jpg

A few things I will mention first though
Presuming you've tried all other adjustments, as this ones a permanent one.
I would not do this if I hadn't done an awful amount of adjustments, but the twisting comment made me write this post.


Presuming, you've watched all the videos first, and tried differing methods like the Snodgrass one aswell as the coplanar way of going about things, and tried the same adjustments with both settings.
Checking for coplanar .jpg


You've looked at the Rikon bandsaw adjustment PDF for the counter procedures of various problems etc and tried them aswell.

If you have tried all else then the way I go about it is as follows, not advising you to do so though!
Attempt this at your own peril
First thing is cut a sheet of plywood to cover the base of your machine...
Yes, you will drop something and chip a huge lump of paint off the machine base.

Get a square block of hardwood and lap the side of a plane iron to make a tough scraper.
You need to be very careful about inserting the scraper into the rubber, as you will cause a split on your tire if you do this wrong!
The scraper needs to be facing away like a scraper plane angle
The f-clamp is just right tightwise and I can twist the block with the clamped plane iron...
Too much and you will damage the tire with a split.
You might need to block up around the back of the machine to get the large f-clamp to fit, and play around with the angle of timber facing into the saw cabinet, before clamping up the blade onto the block.

Then get blisters on your fingers spinning the wheel for ages.
Did I mention cut a sheet of ply for the base because you will chip it, first thing you should do
before anything else tire dressing wise, because all that awkwardness will make you forget about the paint job.
Tired now, so I may not be making sense
Do all else first before going at tires.
Take a picture of the jacking bolts before going at them also, as you may want to know exactly where they were originally.
I may be forgetting something regarding tire dressing , so don't rush out and try that.
As simple as a bandsaw is, they can be very troublesome.
Tom
 

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Pete Maddex

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Mark the wobble in the blade and spin it round a few times to see if its the blade or the tyres that are causing the wobble, my money is on the blade.

Pete
 

Ttrees

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Indeed, what Pete says.
My saw would not cut atall and just burned into the work.
Look at my guides before I welded them and dressed them.
My table has deep nail scratches from pallets or something
VFD bandsaw.JPG

and its had the trunnion bolt snapped off
 

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boardgamer

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Tom, Wow, that's a helluva post. Much food for thought there. I had already cleaned the tyres with a brass brush, so they were fairly clean, although the bottom tyre isn't as flat as it should be. However I gulped and decided I would try Pete's suggestion first. I marked the wheel at the points of maximum wobble as it went round, and found no correlation. Hopefully that meant the wheels/tyres weren't at fault. Next I put my old blade back on, and hey presto, the wobble disappeared! So much for buying a new blade to minimise any setup hassles :roll:

Could the twist in the blade be there because it is new, and has been coiled up for its entire life? Maybe it would come out after a few days/weeks under some tension in the saw, or would you suggest it a defective blade?
 

boardgamer

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Nev, I think you can safely assume that *nothing* is obvious to me..... Except perhaps "obviously" a new blade will work perfectly. :oops:
 

nev

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boardgamer":1by3vs33 said:
Nev, I think you can safely assume that *nothing* is obvious to me..... Except perhaps "obviously" a new blade will work perfectly. :oops:
:D

and I'll do it again ;) Tuffsaws for blades. Apart from jolly good blades if you ever have a fault with a blade Ian will usually replace it without quibble.
 

Lons

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What Nev said.

I don't use up many blades but will buy from nowhere else now. The first blade from Tuffsaws transformed my old Startright 352
 

Marineboy

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+1 for Tuffsaws. I was contemplating buying a scrollsaw to make some cut out animals for a Noah’s Ark I’m making. I thought I’d try a narrow blade on my little Inca 205 first, so I got a 1/8” 14 TPI. Results are superb, very clean cut and able to cope with very tight curves
 
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