Jet Bandsaw & blades

[martin.pearson]

Anyone on the forum have any experience with a jet JWBS-18-M
I bought mine mainly for resawing so most of the time it has a 3/4" blade fitted but my son wanted to do some projects so I bought a 1/2" & a 3/8" blade for him to use. I am having problems with fitting both these blades, the bottom guide carrier doesn't seem to go back far enough for them. With the 1/2" blade the carrier is back as far as it will possibly go & the bearings are barely sitting behind the teeth of the blade, the knurled screw to tighten the bearing is hard against the machine & almost impossible to tighten. The 3/8" blade is even worse because the bearings are sitting past the teeth on the blade lol.
Has to be something I am doing incorrectly but just don't know what, watched all the usual bandsaw blade fitting Videos but that has made no difference what so ever

 

[Lazurus]

Some thing sounds awry, pictures may help.

 

[martin.pearson]

Some thing sounds awry, pictures may help.

Yes I guessed that at the start but wasn't sure what pictures would be helpful, can you give me some idea what might be useful, I know this is something that I must be doing wrong but have tried a number of times & seem to get the same results each time lol

 

[Lazurus]

Show the guide bearing (s) that have the issue to start

 

[Richard_C]

It sounds like the blade might be sitting too far back. Where is the blade sitting on the top wheel, have you adjusted the tracking at all, did you adjust the tracking as you tensioned the blade ?

My machine is much smaller, but to get the blade where it needs to be you have to 'tweak' the tracking and the tension alternately as you set it up. I reference mine by the front of the blade (teeth) so no matter how wide the blade is the teeth are in roughly the same fore and aft position on the top wheel.

 

[martin.pearson]

Thanks people, will take some pictures tomorrow when I am up at the workshop, if anything the blade is sitting to far forward, I originally tried to set it up as I have seen Alex Snodgrass do it with the bottom of the gullet on the crown of the wheel which didn't work so went for the blade being centred on the top wheel which again didn't seem to work so at the moment the blade is sitting slightly forward on the top wheel, yes the tracking & tensioning have been set up correctly as far as I know. I have changed the blade a few times without any problems but it was always a 3/4" blade that I used previously. If I put the 3/4" blade back in I am sure there won't be a problem lol

 

[Ttrees]

Where does the narrower blades track on the lower wheel?, if you cannot get them both the same position on the wheels, then that's likely where the issue is coming from.

If the blades are tracking too far back on the lower wheel, then adjusting the shaft jacking screw at the back of the lower wheel should fix it,
as I'm guessing there is no adjustment for wheel protrusion on the lower wheel.

Moving the shaft south/ 6 o'clock will make the blade track to the front of the wheel.
If the blades are tracking well then disregard that, and level the machine up and check for co planar
(easier said than done on many's a machine which won't sit well on a warped base which can be tipped about with a finger)

I'd not be doing any of that craic without taking off the table though, as anything changes everything in this regard, and sounds like the saw was never set up properly in the first place.