clinton Posted May 21, 2011 Share Posted May 21, 2011 I am planning to pour new bearings for my Commonsense power hammer. I want to start rounding up the material and get every thing ready before I tear down the hammer. It has come to my attention that there are many different grades of babbitt. I was planning to get the material from Hit N Miss, as I have had good luck dealing with them in the past. They have what they call "General purpose" babbitt. http://www.hitnmiss.com/index.html @ $7.00/ lb Sid @ Little Giant has 4 1/2 lb ingots for $26.00 $5.77 / lb http://www.littlegianthammer.com/pdf_files/Babbitting%20Supplies.pdf Then there is Rotometals, they have a variety of babbitt at different prices http://www.rotometals.com/Babbit-Bearing-Alloys-s/2.htm I know some of you guys do this all the time and I have lots more questions to follow Quote Link to comment Share on other sites More sharing options...
Fe-Wood Posted May 21, 2011 Share Posted May 21, 2011 Clinton- I have the little giant rebiuld book at the shop. I'll take a look and see what they recomend.... Quote Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted May 21, 2011 Share Posted May 21, 2011 I've only used the lead-free babbitts. Guess the all must work to one degree or another. Quote Link to comment Share on other sites More sharing options...
BIGGUNDOCTOR Posted May 21, 2011 Share Posted May 21, 2011 If you are looking for some inexpensive babbit, you may want to give Walker's Hydraulics a call, if they are still in business. They are in Concord, CA. I worked for them back in the late 90's and we were pulling in-ground lifts out of old service centers. I was told the upper bearing was babbit. If so it would be a bushing with a 7.5", or 10" ID, and about 24" long. They just took the old lifts to the scrap yard. You could have them lop the top off of a couple when they cut them down. Quote Link to comment Share on other sites More sharing options...
dablacksmith Posted May 21, 2011 Share Posted May 21, 2011 most of what babbit is is tin similar to pewter ...some has a little lead or other alloys figure anything over 90 %tin will work fine i dont think the alloys make that much difference its the tin that is the bearing ... getting everything lined up well is the important part... Quote Link to comment Share on other sites More sharing options...
Ric Furrer Posted May 21, 2011 Share Posted May 21, 2011 I'll be pouring some bushing for a rolling mill here and will use ZA12 form these folk http://www.eazall.com/diecastalloys.aspx ZA-12 is the most versatile zinc alloy in terms of combining high performance properties and ease of fabrication using either gravity or pressure die casting. ZA-12 is the best gravity casting alloy for sand, permanent mold and the new graphite mold casting process. It is also a good pressure die casting alloy (cold chamber) which provides a sounder structure than ZA-27, as well as higher die cast elongation and impact properties. For these reasons, die cast ZA-12 often competes with ZA-27 for strength application. An excellent bearing alloy, ZA-12 is also platable, although plating adhesion is reduced compared to the ZAMAK alloys. Ric Quote Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted May 22, 2011 Share Posted May 22, 2011 Up to around 5% copper is used for hardness and around the same of antimony gives an alloy that doesn't shrink significantly. Quote Link to comment Share on other sites More sharing options...
peacock Posted May 22, 2011 Share Posted May 22, 2011 You will get along good with Little Giants babbit. Where ever you get it use a softer grade. ASTM 10 is good, pours at 630 degrees F. try not to exceed that temp too much. It will not shrink and pull away from the shell as bad as alloys that pour at a higher temp. Also you want a softer babbit so dirt etc. can embed in it rather than score the shaft. High tin content is too hard. Stick with a lead base some thing close to lead 80% antimony in the mid teens tin 2 to 5%. Quote Link to comment Share on other sites More sharing options...
Fe-Wood Posted May 22, 2011 Share Posted May 22, 2011 Here is what the Little Giant Manual by Richard Kern says to use. McMaster-Carr General Purpose, 79.5% lead,15% Antimony and 5.5% Tin. This one looks close- Lead-Base Coppered Babbitt Ready for low-speed, heavy-load applications, this babbitt is hard enough to carry a hefty load without squeezing from the bearing box. Composition is 74.5% lead, 14.75% antimony, 10% tin, .25% copper, and .5% arsenic. Pouring temperature is 700° F (melting point is slightly lower). Supplied in cakes of approximately 3 1/2" dia. thickness and weighing approximately 4 1/2 lbs. Each 8901K71 $33.33 Richard recommends reusing the old babbitt, just adding what you need to make up for the loss caused during removal. Preheat the parts to about 500 Deg. before pouring. You will also want to "tin" the parts so the babbitt will stick. They recommend a 50% tin-50% lead tinning paste. Fun times ahead for you my friend!! Quote Link to comment Share on other sites More sharing options...
clinton Posted May 22, 2011 Author Share Posted May 22, 2011 Ok I will probably go with the babbitt from Little Giant, it is the right stuff and he actually has the best price that I have found. Now I need to figure out how much it will take. The Little Giant web site has a chart and it shows that 4 ingots are needed for a 25 lb hammer if you are using all new babbitt. That seems like allot of material to me, my bearings are 3 1/2 inches long x 2 inch diameter. Also I am wondering if I should reuse the old babbitt and just add some as needed. It seems to me that just using all new would result in a better product, I really only want to do this one time I would rather be making something than working on equipment And thanks to everyone for your input on this Quote Link to comment Share on other sites More sharing options...
Ric Furrer Posted May 22, 2011 Share Posted May 22, 2011 You will get along good with Little Giants babbit. Where ever you get it use a softer grade. ASTM 10 is good, pours at 630 degrees F. try not to exceed that temp too much. It will not shrink and pull away from the shell as bad as alloys that pour at a higher temp. Also you want a softer babbit so dirt etc. can embed in it rather than score the shaft. High tin content is too hard. Stick with a lead base some thing close to lead 80% antimony in the mid teens tin 2 to 5%. How can grit enter? You have a grease zirk forcing in the lube and it exits at the ends of the bushing...all out flow no in? I have a small rolling mill with bronze bushings ..the top half is open to the world and I have a large pile of scale and grease on that from use...after a year of use I removed everything an looked for wear...none visible..no damage at all. I think if you get a proper fit the oil/grease will prevent contamination quite well...again..all the forces is pushing the lube out of the area and not allowing things to get in. Also..Make sure you have shims so you can remove them as the bushing wears. Ric Quote Link to comment Share on other sites More sharing options...
clinton Posted May 22, 2011 Author Share Posted May 22, 2011 There are no grease fittings on my hammer just oil cups, and I am sure they do get grit inside them Quote Link to comment Share on other sites More sharing options...
Fe-Wood Posted May 22, 2011 Share Posted May 22, 2011 Also I am wondering if I should reuse the old babbitt and just add some as needed. It seems to me that just using all new would result in a better product, I really only want to do this one time Only reason I can think of not to re-use the babbitt is that its to hard or to soft. Once you melt the old babbitt, there is no reason not to use it. It doesn't degrade with time... Just don't over heat it. Quote Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted May 22, 2011 Share Posted May 22, 2011 The rule of thumb I learned was if the shaft was pretty much pure rotational likes a line shaft then lead babbitt was fine. If there was reciprocating motion like a crank-shaft then tin babbitt should be used. The lead babbitts can deform easily and pound out. The lead babbitt is also known for work hardening and cracking more easily. Quote Link to comment Share on other sites More sharing options...
peacock Posted May 22, 2011 Share Posted May 22, 2011 How can grit enter? You have a grease zirk forcing in the lube and it exits at the ends of the bushing...all out flow no in? I have a small rolling mill with bronze bushings ..the top half is open to the world and I have a large pile of scale and grease on that from use...after a year of use I removed everything an looked for wear...none visible..no damage at all. I think if you get a proper fit the oil/grease will prevent contamination quite well...again..all the forces is pushing the lube out of the area and not allowing things to get in. Also..Make sure you have shims so you can remove them as the bushing wears. No zirks, no pressure, no seals on the ends of shells. If things can exit on the ends then grit and scale can and will enter there. Also the shims can create gaps along the parting line which can let trash in and oil out. The air in most shops is full of stuff. Next time you have a gas forge going grind on a piece of steel within 25 or 30 feet of the forge you will be amazed as the particals in the air burn in the dragon breath. Quote Link to comment Share on other sites More sharing options...
Ric Furrer Posted May 22, 2011 Share Posted May 22, 2011 No zirks, no pressure, no seals on the ends of shells. If things can exit on the ends then grit and scale can and will enter there. Also the shims can create gaps along the parting line which can let trash in and oil out. The air in most shops is full of stuff. Next time you have a gas forge going grind on a piece of steel within 25 or 30 feet of the forge you will be amazed as the particals in the air burn in the dragon breath. My shop is far from clean and though I have moved the angle grinding a few feet out the front door I still use the belt sander inside. That said...the rolling mill I have has exposed bronze bushings (no zirk just an oil squirt now and again) for the top and bottom roll and I run hot steel through them..so thee is a major scale issue...yet no scaring of the roll or bronze. My 50 weight Molag has bushings and when the shaft was pressed out it to was clean as were the bushings...though there are grease zirks on that one. With the LG and Beaudry we used in Florida we had thick wool cut to fit the oil opening and that acted as a wick and filter of sorts..I do not recall any issues with them either. One can make a coupling of rubber or some such and place the oil drip cup on that...making the pathway very difficult for any shop grit. A few months back I was quoted under $2 per pound for the ZA12 material....but then again I'm getting 400 pounds of the stuff which may make a slight difference in price. Ric Quote Link to comment Share on other sites More sharing options...
wshelley Posted May 23, 2011 Share Posted May 23, 2011 Linotype alloy is also pretty close, 84%-lead, 12% antimony, 4% tin. If you know anyone who reloads and casts thier own bullets they may have some squirreled away. Looks like about $3/pound on the interwebs. Ward Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted May 23, 2011 Share Posted May 23, 2011 I had a friend who made nickle silver caps for the open oil cups on his LG. Easy to pull off and oil it up replace and *go*! Quote Link to comment Share on other sites More sharing options...
Dave H. Posted May 25, 2011 Share Posted May 25, 2011 I don't care to use grease on a power hammer. All the grit & scale mixes with the grease to form lapping compound. I feel oil will help wash scale & crap out of the bearing & slide surfaces. Dave Huffman Quote Link to comment Share on other sites More sharing options...
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