This is mainly for poor souls, like meownself, who have not a clue about babbitts. You can either chisel or melt them out. There are arguments for both methods. I like the arguments for chiseling, i.e. less oil is leached out of the cast iron by the heat and the new babbitt pour will adhere better. The melt-out method would appear to work quite well, too.
I started around the edges, just lightly chiseling. The legendarily brittle nature of cast iron had me all atwitter. Pretty soon I got my back into it and began to really hit the sucker. Babbitt is soft and chips out pretty easy.
Second pic down shows half the babbitt in one of the caps completely out. I found the easiest way to proceed, when possible, was to chisel lengthwise along the babbitt once you could get down in there. It sort of peels out in larger chunks that way.
You can see, below, how one half of a babbitt just popped out. Note the little protrusions; they match the dimples in the cast iron and keep the bearing from spinning inside its housing.
To the right is one cap cleaned out. The thing at the bottom is the hard stuff that was blocking the oil port. Turns out is was just the felt one should find there, but so hardened with age I though it was something else.
.Left is one of the babbitt bodies, the bottom half of a bearing assembly. The oil groove in the bottom of this bearing was packed with what appeared to be manila rope. This babbitt is actually in two pieces since the oil groove goes the entire length of the babbitt. I am not sure just how this will be poured.
Here is the material from the oil groove. One was a twisted fiber, like manila, and the other might be felt.
Left is just a piece of a body cleaned out. The groove in the center is where no babbitt is poured and the felt rests. A point of interest here is that in my virile pursuit of babbitt I actually did take off some cast iron. It shows as the shiny strip and the shiny area below it. The round shiny area to the left is actually one of those little poured nubs of babbit that didn't come out.
And I like this photo to the right as it shows how the babbitt cools unevenly during the pour and leaves wrinkles and blops facing the cast iron.
I am going to throw a quick note in here, as a kind correspondent has asked "What the hell is a babbitt, dad?": babbitt, boyo, is a soft metal, also called white metal, made mostly of tin - about 90%, a little antimony and a little copper. Some mistakenly think it is just lead, and a cheaper form for low speed uses does have a high lead content. It can be melted on the stove and is thus easily used in the home-shop. Its use as a bearing material depends on its being shaped to the shaft, or other part, running on it, usually by hand scraping, so that there is no metal to metal contact, but a thin film of oil is maintained between the 2 moving surfaces. It is oiled by drip from a reservoir that MUST be kept filled. This maintainence requirement is one reason it started to fall from favor as early as 1911. Among its strong positives are: a babbitt bearing can be repoured at home - very low tech; it will last much, much longer than a ball bearing, IF kept properly oiled; it can be taken apart and re-scraped as it wears, to re-fit it to the shaft - it has more lives than the proverbial cat. Babbitts are stone simple. If you are tired of dealing with complex systems that do everything, more than you want even, then look with favor on babbitts; they do one thing exceedingly well with the greatest of simplicity. The idea of pouring my own babbitts is so much more appealing than going to the store to buy new bearings. I am in retromode.
This page was last updated on: August 14, 2006
'Twas silly of me, but i simply didn't want to pour babbitts from a pan, scrounged from goodwill, heated on a campstove, gleaned from a garage sale. i wanted the real thing. so, here it is. this is a gasoline-burning babbitt/lead heater. came from a lot that was in an old machine shop and i paid $75 for the burner and all the pots and ladles pictured.
I spent forever trying to get this sucker working and got nowhere. I was using kerosene, being a bit wary of gasoline, and fuel was welling up from around a fitting. I would open the valve a tiny bit and drip fuel into the pan, light that off to heat the coils, and hope to get a superheated fuel-vapor once the coils heated. no such luck. i would just end up with the entire thing flaming darkly away and no real heat.
Finally, I went to gas and due to its lighter molecular weight I could immediately see that the fuel was not welling up from the fitting below but was actually bubbling out of a porosity in the bronze casting. J.B. weld to the rescue, and now the sucker roars like a jet. I dropped in an inch and a half square piece of who-knows-what metal - about 40# of unknown compostion ingots came with the stove, and in 4 minutes I had a ladle of slinky liquid metal. The heat is there' you can see how the heat-proof green paint blistered on the top. Guess i am exceeding the mfgs. suggested 1100 degrees f.
Since Billy Bob's arbor is back from the machine shop cleaned of its old grooves I just need to set up some v-blocks and do a pour. it was $84 to get the shaft machined: 2 hours at $42 each. my own metal lathe looms; i can feel it in my bones.
How long is it since I wrote the above? Two years? It is now absolutely necessary that I get Billy Bob back in running order as I have machines that need to come into the shop; he is right in the middle masquerading as a pile of junk.
It was obvious that I needed to support the arbor above the bed the babbitt will pour in to, and allow space for my shims. I settled on spacers made of 1/2" flat washers, to mimic shims, and put two nails in under the shaft to get a look at my configuration; I liked it.
Chopping the nails into short segments I pressed them down into the babbitt tite, below left. Below is a pic of the same done on each end. This should give me clearance to pour all the way around the arbor and give me a bearing of the thickness of the nail pieces.
Here I have set the arbor assy. into place and gently pushed it down until it is seated on the nail pieces and damned by the babbitt tite.
I would be ready to pour if the stove weren't leaking again. J.B. Weld is now in place and curing. (The new leak, another porosity, gave me a pressurized lateral flame across the top of the stove of about 15" in roaring length; a very impressive display.)
The white/red arrow points to where I am getting fuel leaks..
Here is the el cheap charcoal forge: the cut-off end of a steel drum with a few fire bricks and about 10# of charcoal.
Bottom left is the 'replacement' babbitt stove. It's a Coleman single burner white gas stove rated at 10,500 BTU.
Right is a closer view of the ongoing pre-heat. The problem with this sort of setup is just getting the arbor assy. braced and level. The heat generated by the charcoal was all I could wish for.
The ends of the arbor where babbitt will be poured have been blackened using an acetylene-only flame. Babbitt will not adhere where this is done.
On the left the bottom pour is done. The little Coleman melted the babbitt faster than I had expected. The secret would seem to be in keeping the sucker pumped enough to produce a hot flame.
I had wondered if my pre-heat would be enough. It was. I found on scraping excess pour from the casting that it was still liquid. I must have pre-heated the assy. to close to the 900 degrees f. needed to melt babbitt. It flowed very nicely when I poured. Make sure and pre-heat you ladle, too; a cold ladle cools the molten babbitt as you pour.
Above I am getting ready to pour the tops while everything is still hot. I have laid in a bead of Babbittrite along the arbor so that the next batch of molten babbitt won't join up with what I just poured. I put the washers in for spacers, placed the cap on and pushed down hard. Don't forget to use Babbittrite around the ends, too.
And below the entire pour is done. I splashed some around, but it flowed so well due to the good pre-heat that I think it will be good.
Finished product. Not great, but not bad. Everywhere that babbitt could go it did; the pre-heat is the important part. Where you see lacunae, as out along the ends, is where I was too free with my Babbittrite. If you have opened up a babbitt and looked at the color differences you have probably noted, on well-used machines, that maybe only half the babbitt was actually supporting the arbor with an oil film. And the machine was probably running fine. I don't know how much babbitt needs to be in contact - the more the better, no doubt, but I think I have plenty of babbitt available here for a good bearing surface. I am going to get the Prussian Blue and scraper out and start seating the arbor. The tops of the caps will need to be drilled out and felt put in, and an oil groove cut in the bottoms. All in all, I think this is going to work.
The thrill-a-minute babbitt adventure continues at the left. I had not lined up the caps very well on the first pour and while that is not a problem on the plain bearing it means the bolt holes don't line up on the thrust bearing. Decided to do both again while I was at it. Set up here: arbor blackened and waiting, both caps and ladle in pot with babbitt for preheat.
I was amazed at how fast it went. The caps alone are much simple, but from start to finish I had them
poured and ready to fit in less than half an hour. For preheat I simply went with the rosebud on the oxyacetylene torch. Melted the first pour out of the caps in seconds, put a ring of Babbittrite around the arbor where the cap ends would be, and cut shims spacers out of cardboard about the same thickness as the washers I had previously used. Next I did a couple of minutes preheat on the arbor, then put the shimstock in place and set the babbitt caps down, aligning the bolt holes, and did a couple of minutes preheat on the caps. By this time the babbitt was liquid, so I just did a pour. Left is just after the pour.
Just a few minutes after the pour I inserted a chisel in where the cardboard shimming lay and gave a tap. Each cap popped right off. The cardboard is fine for this; it does not burst into flame. In fact, I was rather delighted at the way babbitt had flowed down thru the corrugations and made lots and lots of little babbitt pins the width of the shim.
This pour looks better than the previous, but I have still used too much Babbittrite at the ends and left ragged spaces. Hemp, sisal, or felt will fill these fine and hold oil.
The oiling slots need to be opened up. I drilled them out and them sharpened up a half inch chisel to a long point.
Here are the row of holes chisled out. Smoothing can be done with a coarse file.
This is the second set of babbitts I have scraped. Each time I have come to a point where I am no longer sure just what to scrape, the blue or the shiny part. You will find instructions to do both. What I think happens is that somewhere into it you have to switch from scraping the blue, which shows the high points, to scraping the shiny parts, where the blue get wiped off. This does not absolutely make sense to me. This time when I reached that point I started putting on on enough Prussian Blue to dull the finish on the babbitt and arbor, putting them together, hold them so very tightly, and spinning the arbor vigorously for about 30 seconds. I would then pull them apart and I could see burnished areas that I was sure were the high spots, and those I would scrape,
Oh, I chiseled an oil groove about 1/16th" wide and just as deep in the bottom of each babbitt. All I need do now is get my shim stock in and git the torque I want and start BB up.
Days later and the babbitts are as scraped as they are going to get. I think I have achieved the 75% in contact I wanted. On the left is some sisal wound around the arbor ends as seals. Very low tech approach, which is one of the things I love about babbitts: any idiot can probably do this job with success. The first 'seals' leaked oil like mad, so I went to a larger diameter sisal and ''voila!' no more leaks. Here you can see my first shim; since I will need over a quarter inch of shimming I started with a thick piece of leather and added in cardboard until I liked the fit. With the shims in I just tightened down on the caps until I could not turn the arbor by hand and then backed them off a touch till I could. I will be tightening them up again as the babbitt wears in.
Far left is a piece of felt the size needed to fill the oiling slot. One piece is already tucked down in with the ends up. I just squirt lots of 10-30 wt. sae non-detergent down in there.
Left the boxes are in place in the yoke that raises and lowers the blade. The arbor pulley is 4", the motor pulley is 3" and the blade speed from a 3450 rpm motor is then just under 2600 rpm.
