Bandsaw Blade Oscillation and Carter Tires

[Kyle Grymes]

I am trying to keep my old Craftsman 22400 hobbling along until I can afford that MiniMax, lol - and recently swapped the worn out rubber factory tires with Carter urethanes, swapped the bad bearings, etc.

I've tuned it to get a pretty good cut with a new Woodslicer from HH - but I am getting some 'oscillation' from front to back - 1/32" - 1/16". The blades tracks well otherwise- I've got the bottom of the gullets at the crown, etc.

The one thing I can possibly attribute it to is that the new Carter tires are about 3/32 - 1/8" narrower in width than the wheels- and since you dont use glue with urethane they seem to keep shifting on the wheels side to side at different spots around the wheel. I can adjust the tire to bias towards the front OR towards the back edges of the wheel all the way around - but after running the saw for a few seconds the tires move themselves partially. What is a good solution for this? Id like to eliminate it and see if if solves the blade oscillation.

Thanks!

[Richard Coers]

Put a straight edge against the back of the blade over the weld. I'm guessing you have a bad weld joint and should contact Highland for a new one.

[Kyle Grymes]

no its definitely not the blade - the issue existed with the old timberwolf I had on there after I put on the carter tires and new guide bearings. To clarify - the movement I am getting is front-to-back, ie in the plane of the cut kerf, not flutter side to side like a bad weld might cause.

[Richard Coers]

The ends of the blade stock can be cut out of square and then welded. That produces a blade the moves front to back.

[Robert Hazelwood]

I had this issue with the factory Laguna 14bx tires. They are urethane and not glued, and are narrower than the wheel groove. The tires were loose enough on the wheels that you could slide the tire back and forth in the groove by pushing with your fingers. The tires would never stay quite centered within the wheel and so the crown would effectively wander back and forth as the wheels spun, producing a front-to-back oscillation in the blade. Now, the saw still cut quite well and it was not a big problem. For the most part I only noticed it when doing a stop cut like a tenon cheek, you could easily see the oscillation and had to be careful not to overshoot your stop point.

The oscillation was apparent on every blade I used, it was not due to a crooked weld.

I solved this a couple of months ago by ordering rubber tires and gluing them on with rubber cement. As ordered the rubber tires are much wider than the wheel groove so they have to be cut to fit, then glued on and then crowned. Between the custom fit into the wheel groove and the glue, the tires are held firmly in position and the manual crowning produces a perfectly true wheel. No more oscillation. The new tires are noticeably thicker than the old ones, and the blade goes through the table insert a bit to the right of where it was before, but everything still works and the guides have enough adjustment to accommodate.

Basically you either need a tire that is extremely tight on the wheel, or that is tightly fit into the wheel groove, or that is glued to the wheel. I have heard that it is difficult to glue urethane reliably, and I couldn't verify that any of the urethane offerings for my saw were tighter fitting than factory, so I went with rubber and glue.

It is a minor PITA to do the rubber tires, so really think about how much of a real-world problem this oscillation is. For me it was pretty marginal.

[Bill Space]

Just thinking out of the box, but if it is not possible to glue the urethane tires to the wheels, could you possible manually push them to one side of each wheel, and then use 100 percent silicone caulking to fill the void, between the tire and the other side of the wheel, to essentially hold the tire in place and prevent shifting? Allowing it 24 hours to set naturally.

I would probably try something like this if I did not want to go with the rubber tire/self crown route.

[Zachary Hoyt]

I put a set of urethane tires from Sulphur Grove on my bandsaw, it was all I could do to stretch them onto the wheels, they fill the whole width tightly and have never moved in years. I think that having tires that are loose enough that you can push them back and forth sounds like they're not a great fit.

[glenn bradley]

no its definitely not the blade - the issue existed with the old timberwolf I had on there after I put on the carter tires and new guide bearings. To clarify - the movement I am getting is front-to-back, ie in the plane of the cut kerf, not flutter side to side like a bad weld might cause.

As you are hearing, a bad weld generally exhibits itself through the front to back motion you describe. That is why it is everyone's first guess. If the urethane tires are shifting about, they are not a good fit. The urethane tires we put on a 1940's Delta conformed to the wheels well and do not deform or budge under load. The previous urethane tires were not a good fit and would actually leave the wheel under the drive force. This loosey-goosey behavior did all sorts of nasty things to the blade travel.

[Kyle Grymes]

As I suspected it was the tires being zig-zagged across the top wheel causing this. Today I removed the blade, reset the tire to favor the rear of the wheel, and filled the 1/8" 'gap' at the front of the wheel (1" wheel and a 7/8" tire) with epoxy to stop it from sliding forward. Reinstalled the blade and the movement was gone!

[Doug Garson]

Glad you were able to fix it but I'm curious, how did you get the epoxy to fill the 1/8" gap and stay put while it cured?

[Kyle Grymes]

The surface tension of room temperate epoxy was plenty for it to stay put. I used an old beater chisel to shape it and force it in the gap