Band saw guide bearings

[Linusofs]

I have an old (30+ yr) bandsaw that I got second hand. I’ve used it a fair amount without much difficulty. I replaced the old guide bearings with the new upgrade kit. All went smoothly until I actually tried to use it. Now the machine slows way down trying to saw hardwoods. I started with trying to resaw four inch walnut. I had to go at slower than a snails pace. 5/8” nearly new blade driven by a brand new Mark 7. I tried some 2” maple and it also bogged down.

It seems the blade is “wedging” itself between the backup bearings. I set the tension for 1/2” blade. The old backup bearings was twice as wide with a groove and the saw worked ok, just was very noisy. I tightened the bolt holding the backup bearing as tight as I was comfortable. Any suggestions?

[MrPerfect]

Could it be slipping on the wheel tires?

[Linusofs]

I don’t believe it’s slipping on the tires. It slows the Mark 7 down to a crawl. If it was slipping on the tires I would think just the blade would slow down, not the entire machine. The blade did not slip prior to changing the bearings. I’ll try to get a picture the next time I use the bandsaw.

[BuckeyeDennis]

Did you attempt heavy cutting with the bandsaw and the brand-new Mark 7 before replacing the guide bearings?

[JPG]

The is no way a blade wedging between the dual guide bearing will stall a properly working Mark 7. Something else is going on.

[Linusofs]

I installed the dual backing bearings concurrent with getting the Mark 7. I still have to old bearing. I may try to reinstall it and see how that goes. Thanks for the suggestions.

[BuckeyeDennis]

The horsepower advertised for a PowerPro headstock is what's available at sawing speeds, but it drops off considerably at low RPMs.

Does anyone here have experience making heavy bandsaw cuts with a PowerPro? I have a mechanical headstock myself, so I don't know what performance should be expected.

[chapmanruss]

Linusofs,

I want to be sure we are talking about the same bearings and where they are in the Bandsaw. The Backup Bearings are in the Upper and Lower Guides use single bearings for both the old "bearings" and the new upgrade/current bearings. A pair of Bearings are now used for the Auto Track Blade Guide located next to the Tensioning Assembly. Older Bandsaws used a single bearing, or a roller to be more accurate, for the Auto Track Blade Guide and upper and lower Guides. It is these older rollers used in the Bandsaws that make a lot of noise if not kept properly lubricated. It is hard to keep them properly lubricated so going to actual bearings is an improvement.

You said,

It seems the blade is “wedging” itself between the backup bearings.

Are you referring to the Auto Track Blade Guide or do you have double bearings in the upper and lower Guides? Are you possibly using bearing setups from another source?

Beside other cutting I have done some resawing on my Bandsaw of cherry wood up to around a 6" cut without a problem. That Bandsaw has the current OEM Bearings and works without the Blade trying to wedge itself between the tracking bearings. I have used this Bandsaw on both Conventional and Power Pro headstocks.

When installing the Bearing Upgrade Kit, it is important to use all the upgrade kit parts to replace the corresponding original parts.

[Linusofs]

I was FINALLY able to get back in my shop after weeks of too cold weather. I we sawing again today and had the same issue, but even worse. This time I paid more attention to the PowerPro and noticed the output shafts (all of them) slowing or stopping but the speed indicator staying about the same. So, I don't think the problem is the bearings. There is something wrong with my PowerPro. I have contacted Customer Service (this is a brand new machine).

Regarding the original post about the blade wedging "between" the bearings, it was the "guide" bearings, not the backup bearings. It still does work its way between the bearings a little.

[JPG]

Two things come to my attention:
1) Assuming the picture is NOT upside down, the blade teeth direction is backwards.

2) The bearings do not appear to be tight against each other. The inner races should be jammed against each other. There should not be a gap between the outer races.

As an aside, the 'new' SPT parts pages in the website suck. More about that in a separate thread.

It was an attempt to determine if the pix was upside down that that suckiness was discovered.