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 Subject : Re:Bearings.. 11/20/2020 12:09:19 PM 
ROBERT SCHNEIDER
Posts: 5
Location
The big Tannewitz bandsaws are nice machines.

We never had to replace any guide bearings in the 20+ years of cutting urethane foam (20 to 45lb density) and plastics. Just greased them occasionaly
 Subject : Re:Re:Bearings.. 11/20/2020 09:57:45 AM 
JILL KENIK
Posts: 6
Location
Those are some impressive machines. Never thought about a bandsaw being 20 feet long! Thanks for the note about still needing to replace the sealed bearing every year. I'll keep watch and keep a bunch on hand. My bearing guru tells me Japanese bearings and US bearings are worth the extra money.

I was wondering what the down side to block bearings was and clearly get your point. I thought it would be heat from rub friction, but particle buildup and pitch would be a major issue.

In my free time, I'll develop some amazing guide system to change the planet! Could use an interesting project that makes me rich!
 Subject : Re:Bearings.. 11/19/2020 02:39:35 PM 
Alika Brooks
Posts: 1
Location
Hi Jill, We have a 24" Tannewitz that we use for resawing lumber in our woodshop. I has a pretty good solution to this age old problem. The bearings are inside a larger steel guidewheel with zerk fittings to grease them. The back wheel or thrust wheel has a groove in it that the blade rides in. It works well and holds up to a good amount of abuse in a production millwork shop.Still need to be replaced regularly though, maybe once a year for us.

https://www.tannewitz.com/tannewitz-products/part-r0472c/

On our smaller Extrema band saw we used sealed bearings. They work fine when they work but still need to be replaced a few times a year. We just keep a handful of the cheapest version that the local bearing supply shop carries, usually made in china, and treat them as a consumable.

The block type also work well. They gum up with wood resins too fast for us, especially with pine. Bearings are quicker to replace and less finicky to adjust, if at all, after replacement.

If you invent a better solution, I would be a buyer :P
 Subject : Re:Bearings.. 11/19/2020 11:30:25 AM 
ROBERT SCHNEIDER
Posts: 5
Location
Sounds like you covered everything. Maybe bad brazing on the teeth, which I wouldn't expect from a high dollar blade like that.
 Subject : Re:Re:Bearings.. 11/19/2020 11:16:14 AM 
JILL KENIK
Posts: 6
Location
I have the bearing located just behind the gullets and the side bearings are a whisker from touching, so my setup should have been correct.
Problem I believe was that several of the bearing froze. That's what sent me on this chase. Its a PowerMatic 14" with 6" riser blocks, upgraded with Carter tires and Kreg fence and mitre. Also have the Kreg micro-adjuster on the fence--fanstastic if you've never used one.
I'm running a 3/4" wide Laguna ReSaw King with carbide teeth. 3/4" is the maximum my saw can handle.

All straight cuts along a fence or mitre gauge.

If its not the frozen bearings that ruined the blade, I'm open to other ideas. First ReSaw King I used lasted a year before its first resharpening and then another year after the resharp. Past 3 blades I've had trouble knocking the teeth off. Doesn't fully strip the teeth---first one pulled off about a dozen teeth on a 105" blade at 3TPI. Last week it knocked off about every 13th tooth, which sounds like it hit a nail, except for the point that I'm the only one that uses it, the blade was less than a month old and since I pay for the blades, I'm careful about what I cut.

All cuts are urethane board, some brass, some pewter---all clean.

After replacing the guides, changing the tires and switching to a zero clearance insert, checking wheel bearings and belt tensions, I installed a cheaper bi-metal Wolverine blade just to see what happens before I reload another $$$ blade.

Grateful for any other insight. Not a top line bandsaw,I know, but should certainly suffice for what I'm doing with it.
 Subject : Re:Bearings.. 11/19/2020 11:00:19 AM 
ROBERT SCHNEIDER
Posts: 5
Location
Jill, some questions.
If the teeth are getting knocked off, maybe the side guides need to be moved back beyond the gullets?.
What blade width are you using? Can you use a wider one for more side support?
Once you have the saw running, is the back of the blade pressing hard up against the back bearing or just glancing?
Bob
 Subject : Re:Re:Re:Bearings.. 11/19/2020 09:40:35 AM 
JILL KENIK
Posts: 6
Location
After a phone call from an APMM'r, I was convinced to go with the Carter Bearings. Mitch--I was wondering about the block style guides, good to know they work well too.

Not a great experience so far with the Carters---my saw required a Universal kit, vs a dedicated kit, so the 15 minute job turned into a 3 hour mess and a phone call with Carter's engineer, until I made all the adjustments. We'll see if this does the trick in preventing the carbide teeth on my $150 Laguna Resaw King blades from getting knocked off. Amazing blades by the way.

Thanks for the help!
 Subject : Re:Re:Bearings.. 11/06/2020 03:45:14 PM 
MITCH HEYNICK
Posts: 2
Location
In my old shop I replaced the roller guides with a system invented and manufactured by a guy here that used carbide guides - no bearings at all. It was really good and super reliable - and never wore out. He wore out however and retired, and nobody picked up the system to continue.

These days, at the university where I used to work, we bought Felder (Austrian) bandsaws with ceramic guides that work similarly. I wouldn't go back to roller bearing guides again.

https://www.felder-group.com/en-us/x-life-band-saws
 Subject : Re:Bearings.. 11/06/2020 01:50:30 PM 
TERRY WELLMAN
Posts: 7
Location
Jill,

Tak a look at Carter Products. https://carterproducts.com/band-saw-products/band-saw-guides

They're stuff works.

Terry Wellman
St. Charles Model Works
 Subject : Bearings.. 11/06/2020 01:43:11 PM 
JILL KENIK
Posts: 6
Location
Need to replace the guide bearings on my bandsaw, yet again--10 pieces. Stock bearings are shielded, which jam with dust and seize. Thought I should upgrade to a sealed bearing, but I see that sealed bearing range in price from $1 each up to $25 each.

1. What's the performance difference between a rubber sealed bearing and a polymer sealed bearing.

2. Can I use a sealed bearing, or will too much heat be generated?

3. Should I continue to use shielded bearings and simply increase the change out schedule? It a bit of a pain to replace and readjust the full sets.

Just spent some decent time researching this online and am unable to make sense of the information. Can anyone enlighten and educate me on bearings?
 
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