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General Forestry => Sawmills and Milling => Topic started by: miro on May 19, 2017, 06:26:41 AM

Title: What Oil for the main bearings ?
Post by: miro on May 19, 2017, 06:26:41 AM
Here's our mill

https://www.youtube.com/watch?v=HIOw4lyoCjE

The fella who restored it about 6 years ago, gave us a gallon of bearing oil which we are about to use up.
He didn't say what grade or type it was. We still have some but we're quite literally getting to the bottom of the bucket.
The main bearings are babbit ( re-poured)
He's now pretty well out of commission.
The blade runs at 500 RPM.

So, what type and grade of oil would you all suggest?

Miro
Title: Re: What Oil for the main bearings ?
Post by: Kbeitz on May 19, 2017, 06:44:14 AM
babbiting and lubrication

https://books.google.com/books?id=b6wJAAAAIAAJ&pg=PA291&hl=en#v=onepage&q&f=false
Title: Re: What Oil for the main bearings ?
Post by: bandmiller2 on May 19, 2017, 07:20:13 AM
Miro, I believe the frequency of oiling is most important. Is it just a simple depression in the top cap where you oil or is there a cotton waste material that gets saturated with oil.? Buy pouring the little oil you have left into a paper cup and back you should be able to compare the viscosity. Myself I would use what they call machine oil, what they use on machine shop equipment. When I ran my shingle mill with babbit bearings I used Fisk petroleum Lubriplate #2 or 3. What I'am trying to say is a little and often. Frank C.
Title: Re: What Oil for the main bearings ?
Post by: grouch on May 19, 2017, 09:14:51 AM
In case you want even more to read...

What oil for babbitt bearings? (http://www.practicalmachinist.com/vb/antique-machinery-and-history/what-oil-babbitt-bearings-157298/)
Title: Re: What Oil for the main bearings ?
Post by: miro on May 19, 2017, 12:07:34 PM
The bearings have a small open reservoir cast into the bearing cap.
The reservoir was filled with clean waste cotton to act as a filter then saturated with oil.
We lubricate the bearings about 1-2 hours before start up, roll the blade over by hand several turns  and as we mill I look for the occasional drip of oil onto the floor.
Looks like a 30 weight DTE  / machine oil ( non-detergent) is the thing we should get.
Thanks, all

Miro
Title: Re: What Oil for the main bearings ?
Post by: stihltoomany on May 19, 2017, 05:39:49 PM
We used shell turbo 46 at the steel mill on motors with babbitt.
Title: Re: What Oil for the main bearings ?
Post by: bandmiller2 on May 19, 2017, 08:12:46 PM
Miro, I think your spot on with the #30 DTE . What concerns me more is the saw slowing down in the cut, is the flat belt slipping or is the engine pulling down. What are you using for a power plant.?? Frank C.
Title: Re: What Oil for the main bearings ?
Post by: miro on May 20, 2017, 09:28:42 AM
I agree with you 100% !

The mill is slowing down because we do not have a powerful enough engine to drive it.
It is a Case Model 30 stationary which ( apparently) is known to have a "lazy' governor, that is slow to respond.
The belt does not slip.
I've made sure that every tooth is at the same height ( within about 10 to 15 thou) , has the right geometry of the wood we mill ( pine) and is dead sharp. I use a Andrus jig to sharpen, touch up often,  and I refer to the US Dept of Forestry book a lot. I replaced all the teeth last fall before we closed it for the winter.

The only other option is to get smaller logs but since we get them donated by local loggers, it's difficult to reject logs.

I've thought about slowing the feed by 10% - 15% - that should help.

But the basic problem remains ( not enough HP)  and the prospect of getting a bigger engine is not very good.
So, given that we only use the mill to demonstrate  "olde' technology , we're pretty well forced to use what we have.

BTW the mill has a patent date of May 26, 1868  and a second, Oct 3, 1869 cast into the frame of the mill. It's a Waterous mill out of the Brantford Engine Works in Ontario  and we think it's one of the oldest Canadian made mills, still in operation, so we're pretty careful about running it.

miro
Title: Re: What Oil for the main bearings ?
Post by: Kbeitz on May 20, 2017, 09:33:11 AM
I wonder if you could add a helper engine to it.
Kinda like a pony motor. Something to help it along.
Title: Re: What Oil for the main bearings ?
Post by: bandmiller2 on May 21, 2017, 08:14:36 PM
Miro, slowing the feed will help which is what your doing when feathering the feed. You are retaining an old historic mill so changing things is not really an option. On my Chase/Lane mill I used a four speed machine transmission for the feed, Hard oak first gear, big pine second gear, light pine third never use fourth too fast for this old guy. Do you have any parasitic loads on the engine like sawdust blower or anything else you could remove.?? Frank C.
Title: Re: What Oil for the main bearings ?
Post by: Ianab on May 21, 2017, 09:20:30 PM
Would a blade with less teeth and a slower feed rate be practical?

Simply reducing the feed speed helps, but each tooth still has to cut through the same amount of wood fibre, just taking a smaller chip, so it's not working efficiently. 1/2 the power might mean 1/4 the speed.

With 1/2 the power and 1/2 the teeth, you should be able to cut efficiently, at 1/2 the speed.

Rule of thumb seems to be 2 or 3 hp per tooth, and that seems to apply whether you have 4 teeth and 12 hp like my mill, or 50 teeth and 120 hp like a big circle mill. The feed rate on the big mill is of course ~10X faster as you would expect. But each cutter is being driven through the wood with pretty much the same power in both cases.

This wouldn't change anything significant on the old mill, just make it work a lot sweeter.
Title: Re: What Oil for the main bearings ?
Post by: killamplanes on May 21, 2017, 10:02:13 PM
I would just be happy somethin that old still works. I can't get 3yrs from a brand new weedeater.  Your not trying to have a 5 man crew grossing 15k a week to pay the bills. Are antique society here uses steam powered tractor to run of circle mill. Painfully to watch but in its day it was sliced bread ;D ;D
Title: Re: What Oil for the main bearings ?
Post by: Kbeitz on May 22, 2017, 01:30:14 AM
Quote from: killamplanes on May 21, 2017, 10:02:13 PM
I would just be happy somethin that old still works. I can't get 3yrs from a brand new weedeater.  Your not trying to have a 5 man crew grossing 15k a week to pay the bills. Are antique society here uses steam powered tractor to run of circle mill. Painfully to watch but in its day it was sliced bread ;D ;D

Wow... One of my stihl weed eaters is 20 years old and still going strong.
Title: Re: What Oil for the main bearings ?
Post by: bandmiller2 on May 22, 2017, 07:20:22 AM
Ianab brings up a good point you could have every other tooth cut, that would reduce your power requirements. There must be a bit in every socket but the fallow ones can be old bits ground down so they don't cut. I personally have never tried it as I've had enough power in the two mills I've run. Long term I would try to find a good sized diesel, possibly from donation or new member. Frank C.
Title: Re: What Oil for the main bearings ?
Post by: miro on June 09, 2017, 09:44:21 PM
Thank you all for the many suggestions and ideas - that's why I like this forum.
I've been away and sawing - usually we saw pine, but a new member of the club brought in some red oak,
and yup that old mill and engine were at its limit - feathering the feed was the only way to cut the oak.
But we did it - new member loved it and gave a nice donation too.

I am still strugling to now find a supplier of the oil we need. seems that any one i speak to or email to simply has no idea about babbit bearings - one fellow even suggested i ought to using grease - ha!

So - I still need help on this.
Is there a reputable supplier of lubricants in Ontario that any of you could suggest?
Heck - if not that , maybe a US based company  - I'll pay the difference in exchange rate and shipping if i have to.
I really want / need to protect those bearings.

miro

ps - next time I'm out at the sawmill I'll suggest to the club we implement the "every second tooth" idea and give it a try.
Also - thanks for the 2 or 3 HP per tooth  - we've got 30 teeth ( as I recall but maybe a little less) and we have 30 HP
No wonder we slow down.
Title: Re: What Oil for the main bearings ?
Post by: miro on June 09, 2017, 09:49:45 PM
Oh - one more thing - no there are no parasitic loads on the engine - our sawdust extractor is run by an electric motor.

We can slightly reduce the feed rate ( 10%) by increasing the diameter of one of the flat belt pulleys on the feed system - some club members might get a bit twitchy about modifying the mill too much.

miro
Title: Re: What Oil for the main bearings ?
Post by: Kbeitz on June 10, 2017, 02:51:25 AM
Ask your oil question here and I'll guaranteed that you will get an answer...

https://www.smokstak.com/

I did a search on this sight and came up with lots of talk on babbit.

https://www.smokstak.com/forum/search.php?searchid=7567232
Title: Re: What Oil for the main bearings ?
Post by: bandmiller2 on June 10, 2017, 06:52:30 AM
Miro, I would not be overly worried about oil, in reality anything you would put in your tractor will be fine. Modern bearings are Babbitt and its just a thin coat on a shell. Retaining the oil in the bearing is more important than what type , something tacky like the old STP or Motor Honey added to oil makes it act like bar and chain oil and not sling off as fast. Frank C.
Title: Re: What Oil for the main bearings ?
Post by: Ox on June 10, 2017, 07:15:15 AM
I use gear oil if I can in oil wells for moving shafts.  Motor oil if I have to.  Grease works too.  I've seen grease fittings, factory, for babbit bearings, on buzzsaws for one.  Nothing wrong with that and I think I'd prefer grease over oil.  Grease is oil carried by a base of soap or lithium.

Taken directly from Wikipedia:  Greases are applied to mechanisms that can only be lubricated infrequently and where a lubricating oil would not stay in position. They also act as sealants to prevent ingress of water and incompressible materials. Grease-lubricated bearings have greater frictional characteristics due to their high viscosity.

Guess I now know why I prefer grease.  It stays put much better than any oil.  I'm thinking this whole thing might be overthinking something that's very very simple.  I know why you are, I'm not knocking you.  But basically if one puts something slippery and petroleum based in there it'll do the job.  :)

It would be great if you could install grease cups.