portaband saw head "oscillating"

[texastiger]

I have a Milwaukee portaband saw and noticed some unusual behavior recently. I made a plate to mount to the saw and in turn clamp to a bench vise so I could keep the saw in a vertical position. While making a cut I noticed that the top wheel (the one that can be slacked to replace a blade) was oscillating while the saw was running. The wheel oscillated about 3/16 of an inch up and down. I checked the tension lever to make sure it was tight and made another cut. Again the same oscillations.

I have never seen this before since when I am making a cut using it in the conventional manner I am not looking at the wheels. Is this oscillating motion normal? Is there some adjustment I do not know about? It was always my impression that the adjustable wheel is moved to tension the blade and remains in that position until it is slacked off.

[Sandy]

It's a push spring tension affair. Normal movement with that saw.

[texastiger]

Thanks for the reply.

The folks at Milwaukee didnt say anything about this being normal. In fact they only thing the suggested was take it to a service center.

[jweller]

I've got that same saw and like you never looked at the wheels while it was running. I would just boil it down to this though, how does it cut? if it's not cutting straight, then it's a problem.

I'm also kinda curious how you have mounted it for upright use. I've tossed that idea around in my head a couple times. got a pic?

[texastiger]

Dont have a pic right now of how I mounted it. I will try to get one and post tomorrow morning.

Basically the "mount" is a plate that bolts to the 4 screws securing the handle at the top. The plate is wider than the handle so I can swivel my bench vise around and clamp the sides of the plate in the jaws. The bottom of the saw rest on the workbench. Without some kind of improvised table and miter slot in that table it is real hard to make anything resembling a straight cut.

[Sandy]

Thanks for the reply.

The folks at Milwaukee didnt say anything about this being normal. In fact they only thing the suggested was take it to a service center.

We've had two at work stretched out over quite a long time frame and I've got one at home, all have the same little action thing going.

[IRONLORE]

It's normal action. I think it is a type of "shock absorber" deal. Causes no problems for me, but the blade bearings need to be replaced with a lot of use sometimes.

Glenn

[Vicegrip]

i have the same saw. Check the tires on the wheels to see that they are seated and don't have something stuck in or under ether one. An egg shaped wheel or a chunk of crud will make the tension end wheel move up down.