Oil or grease on a hammer slide

[Syd Partridge]

I have a Platt Goliath power hammer with a dovetail slide. Currently I use oil to lubricate the slide but I have a problem with my top tool moving sideways, although it is held tight. When I remove the tool the rear dovetails are covered with oil and I'm wondering if this is what is causing the tool to slide. I don't have this problem for a while if I clean off the oil and re-position the tool.
Are there any thoughts on whether grease might be a better lubricant for the slide?

[basher]

You are going to be hard pushed to get your hammer to hit completely vertical , the goliath has quite a bit of dovetail overhang and some of that circular motion will transmit into the blow.
I have the same problem and have re aligned the slides as tight as possible to keep the blow square and find it works for less than half a day before the hammer is turning my square stock into a parallelogram.
I would be very surprised if grease solved this but if it is the case I would love to know .

[basher]

As an aside you should really guard or leather wrap your springs as I have had springs go on every samual platt hammer that I have owned (3 now). mine were all wrapped and it was uneventful but a spring shattering could kill.

[Harmless Dave]

Hi,

Just built a tire hammer with Clay Spencer in Dec. He was adamant that ONLY oil (10-30w) be used on the hammer slide and the toggle linkages. He has seen greased hammers slow down and completely stop.

Harmless Dave

[peacock]

I have an opinion about grease on the ways. I think if the guides are not kept in very close adjustment the grease collects slag and rapidly were the ways. Oil and lots of it tends to flush the crude out. Now I have that out of my system, I will address your problem, the biggest problem is the combination dies. They force you to hammer off center. It appears that about 1/2 of the ram is sticking out the bottom of the frame. This lack of support at the bottom of the stroke forces the ram to kick sideways. Combination dies on hammers with short guide is a less than an ideal setup. If you can shift the dies to the left so the flat part is in the center of the ram without the dies hitting the frame or dovetail slide you can check to see if this helps. Just be sure to not hit anything in between the part of the dies sticking out



After reading JNewmans post I think I misunderstood the problem. I agree with him about the need of good key fit. I don't lube my keys and I do not have trouble with them coming out in use or getting them out when I need to remove them. When I make the key I don't grind them to fit I upset them hot .Clifton Ralph showed me how to do this years ago and it is quicker and gets a perfect fitting key every time. Make a key for each die and keep it with that die only.

edit: 2/18/12

[Tommy Traylor]

Sid at Little Giant says use chain saw bar oil and I have had good results.

[macbruce]

I use whatever oil is handy.....Sometimes bar & chain, atf, motor oil...etc. They all work....One thing I like to do every so often is soak the slide bearings with WD 40 till it runs out and cycle the hammer. It washes the particles out nicely then I go back to oil.....

[E.F. Thumann]

I rebuilt my Fairbanks, except for the main shaft (I didn't want the trouble of line-boring the head), and as such, want to make sure the hammer stays in a tip-top condition. The one thing you have to remember about older hammers (that don't have adjustable babbit caps) is that when you have a significant amount of wear around the main shaft, that free-play between the shaft and the bearing doesn't let a dynamic oil film stay on the shaft. Common shaft-to-bearing fits range from approx. .001-.0015, that's what you want for a proper oil film, my hammer probably has about .015 play in the main shaft, so I replaced the oil fittings with grease, and it runs perfectly fine. If I recall, Dan Seaver did the same thing on his Fairbanks. That being said, I would NEVER run grease on my ways, as that is the part of hammer that is exposed to scale and grease tends to collect little bits etc. I run machine way oil (vactra #2) on the slides/ways, and oil the hell out of it. I think Grant mentioned a while ago that grease doesn't shear like oil does, which is completely true, the viscosity will slow down the hammer. Fact. It will do so for all machine tools in a grease vs. oil scenario. As an aside, Grant also said in one of his last posts about Tim Miller's custom dies "grease and scale make a wonderful grinding paste." Think about that, because it comes from a man who spent his life doing industrial forging (RIP Sarver).

[dan_m]

The one thing you have to remember about older hammers (that don't have adjustable babbit caps) is that when you have a significant amount of wear around the main shaft, that free-play between the shaft and the bearing doesn't let a dynamic oil film stay on the shaft. Common shaft-to-bearing fits range from approx. .001-.0015, that's what you want for a proper oil film, my hammer probably has about .015 play in the main shaft, so I replaced the oil fittings with grease, and it runs perfectly fine.

Yesterday I was cleaning the Scranton hammer I'm fixing up and took the bearing cap blocks off the main shaft. Mine seems like this type of bearing—no babbitt inserts, the shaft just spins in machined grooves in the cast iron. The oil reservoirs on the cap blocks are pretty large, and when I filled them after putting it back together the rear one stayed mostly full while the front one emptied almost immediately. Any thoughts on whether this indicates the condition you are referring to? There doesn't seem to be any slop or play in the shaft and it spins well, but I don't have it hooked up to a motor yet so that's just spinning it by hand.

[JNewman]

The loosening top die seems to be the real problem here.

I always oil or grease my die keys as per the Massey manual, that way when I want to remove them they will come out. Now that they are well fitted I rarely have to tighten the keys. It is important that the keys fit almost perfectly. Clean the dovetails die and key up. Get some Hi-spot ink apply a THIN layer on the dovetail and dovetail of the die. Drive the key in lightly and remove. File off the high spots as indicated by the ink on the key, and repeat. You want a minimum of about 70% of the key to end up blued. if they are well fitted this way they will stay tight much better.

[Old N Rusty]

I use a product called "Neva Sieze" on the hammer guides (L.G.100) and 30 wt oil on all the other moving parts (except the motor) this hammer is a real mess, with scale build-up and oil. Think I am gonna have to pressure wash it with gasoline.

[basher]

syd, are you talking about the top die moving sideways in the tup or the whole thing moving in the vertical slides?
If you are talking about the top die there should be a recess in the top of the top die and also bottom of the tup . this takes a round or square peg and stops the die block moving sideways in the tup.
if there is not one in the top die either drill a recess and insert a peg or weld a peg ontop of the die.

[macbruce]

Think I am gonna have to pressure wash it with gasoline.

I hope you don't smoke when you do that......... :unsure: :lol:

[Dan P.]

When I make the key I don't grind them to fit I upset them hot .Clifton Ralph showed me how to do this years ago and it is quicker and gets a perfect fitting key every time. Make a key for each die and keep it with that die only.

Peacock, could you elaborate on what you mean by upsetting them hot?
Thanks & Regards,
Dan

[peacock]

I have posted this sometime ago but can't find the link. forge a blank that is at least 12 in. longer then your hammer dove tail. You want 4 in. sticking out past the die. It needs to have a taper that will bind in the small end of the opening made by the die and frame. With a torch heat about an inch of the key next to the part that binds, With it very hot quickly put the key in the hammer a hit the big end upsetting the key into the opening. Let it cool a little drive the key out. Now repeat this process 1 inch at a time till the complete length of the die has 100% contact along the length of the key. The area outside the die maybe upset at the edge of the die making a shoulder at that point, forge that down to continue the taper. Trim and bevel the ends of the key to your liking. One note of caution the dovetails on the die and hammer frame must not have holes or voids if you want to use this system. If there are any holes the key will upset into them locking the key in place

[E.F. Thumann]

Manders,

Sorry to leave you hanging all day, I just got in from the shop. I actually didn't mean your type of bearings, I was talking about "captive" bearings that are bored/pressed into a hammer frame like the fairbanks. But wear (and the issues that that entails for maintaining a good oil film on a shaft) applies to the cap-bearing style hammers too. The difference is, that with the caps you can adjust out the wear by cutting the top cap down a bit in a mill. Eventually if It gets horrid, you will have to rough it out and pour babbit. What viscosity oil are you using in SSU/ISO? (people tend to get confused b/c people keep refering to oil in SAE, when talking machine oil it should be refered to in ISO). Did you media/sand blast the caps to clean out the holes in the caps that the oil passes through? How big are the holes? If they are an "open reservoir", meaning just a depression in the casting, you should either tap the holes for a grease fitting/oil cup (make sure it is a wicked cup), or machine a brass plug that has a center hole tapped in it, that you can gently seat into the hole if you don't feel like tapping the iron itself. It's normal that the front cap would drain, and the back cap drains much slower, b/c on these hammers, the front bushing takes the majority of the radial load (same reason why lathes have larger/stronger bearings right behind the chuck vs. their rear bearings). P.S. use a dedicated oil or grease for the task that it's meant for. Literally millions of man-hours over the last century have been spent tailoring lubricants to specific tasks, take advantage of it. I tell all of my guys in the shop: oil is cheap, machines are expensive, use more than you think the machine needs. P.s. Phil, upsetting keyssssssss!!!!!!!!!!!!!! I missed the forest for the trees when I was spotting my keys in, I will be trying the upset method this weekend:)

[Syd Partridge]

Thank you for all your comments. It seems I now need to address a number of issues.

Having again looked at the slide, I noticed there is a lot of movement between the dovetails and slide. I will adjust this.
Basher - Originally there were pegs on the underside of the tools but these have long gone so I will have a look at making a peg.
JNewman and Peacock I think this may be the key (excuse the pun). The keys got mixed up when we moved the hammer and I relied on memory as to which key fitted which tool. Also as the keys are old I have to rely on shims as well as the key. This may be compounding the issue - I will make some new ones.
Basher Thank you for the comment on guarding the springs. They've been on 36 years to my knowledge so it might be as well to cover them before they finally fail.
With regards to oil or grease; I work with copper so the scale is light and does tend to lift so it may cause a problem mixing with grease. I will carry on with oil as per many of your suggestions and see if the other adjustments cure the problem.

[dan_m]

Manders, Sorry to leave you hanging all day, I just got in from the shop. I actually didn't mean your type of bearings, I was talking about "captive" bearings that are bored/pressed into a hammer frame like the fairbanks. But wear (and the issues that that entails for maintaining a good oil film on a shaft) applies to the cap-bearing style hammers too. The difference is, that with the caps you can adjust out the wear by cutting the top cap down a bit in a mill. Eventually if It gets horrid, you will have to rough it out and pour babbit. What viscosity oil are you using in SSU/ISO? (people tend to get confused b/c people keep refering to oil in SAE, when talking machine oil it should be refered to in ISO). Did you media/sand blast the caps to clean out the holes in the caps that the oil passes through? How big are the holes? If they are an "open reservoir", meaning just a depression in the casting, you should either tap the holes for a grease fitting/oil cup (make sure it is a wicked cup), or machine a brass plug that has a center hole tapped in it, that you can gently seat into the hole if you don't feel like tapping the iron itself. It's normal that the front cap would drain, and the back cap drains much slower, b/c on these hammers, the front bushing takes the majority of the radial load (same reason why lathes have larger/stronger bearings right behind the chuck vs. their rear bearings). P.S. use a dedicated oil or grease for the task that it's meant for. Literally millions of man-hours over the last century have been spent tailoring lubricants to specific tasks, take advantage of it. I tell all of my guys in the shop: oil is cheap, machines are expensive, use more than you think the machine needs. P.s. Phil, upsetting keyssssssss!!!!!!!!!!!!!! I missed the forest for the trees when I was spotting my keys in, I will be trying the upset method this weekend:)

No problem, thanks for the response. I didn't need to sand blast them, there are integral cups each with 3/8" holes, so plently of room to just scrape the crud off:


I have Vactra #2 way oil that I used, it's ISO VG 68. It's just what I had around, should that work alright or is it too thick? I'm getting a motor and some flat belt pulleys this week, so it's not even running yet, I've just been cleaning it up and fixing a few things in the meantime. I can't feel any slop when I spin the shaft by hand though...do you think the quick drain from the front oil cup necessarily indicates wear to the point that it should be repaired, or can that still happen and the wear level not be excessive? Thanks!

[JNewman]

The locator pins on the dies will probably help with keeping the keys tight as well. My Sow block used to come loose about once a month if I was doing some heavy off center forging. I put in a center pin and have not had to tighten it since. I have a treadle guard/tool tray that has to be removed to to tighten that key so it was well worth the machining I had to have done to the sow block for a pin.

[JNewman]

Here is a thread on keys and center pins http://www.iforgeiron.com/topic/12641-dovetail-keys/page__p__148174__hl__massey__fromsearch__1#entry148174

[Syd Partridge]

Thank you for the link to the thread on keys and center pins. Really useful info.

[iron quake]

I’ll throw this out for what it’s worth. I’m not knocking any of other choices for slide way or ram lubricant folks have suggested ( bar oil, motor oil, grease, buggers whatever. If it works for you then why change. That being said, and keep in mind I’m very new to this power hammer game, I’m using way lube, Chevron Vistac because, I have it for my other machine tools and Its made exactly for this application. People in the machining industry would never (I don’t think) use anything but way lube for machine ways and slides in tools costing tens or hundreds of thousands of dollars. Here is a blurb on what I’m using. I could be full of you know what, and if my ram seizes up I’ll let you know.
Chevron Way Oils Vistac provide extreme pressure and antiwear protection and have stringiness and oiliness characteristics. As indicated by part of the name, Vistac, these lubricants have an unusual adhesive or tacky quality. It wants to stay on a vertical surface.
Chevron Way Oils Vistac reduce leakage and adhere to metal surfaces providing a tenacious lubricant film. Chevron Way Oils Vistac are formulated to meet the critical lubrication demands for the slides and ways of machine tools.
Their inherent low coefficient of static friction eliminates stick-slip or jerky motion of sliding parts on machine tools which increase operating efficiency of the tools and smoother overall operation.
Due to their adhesiveness, these oils form a tenacious film which resists being wiped away by the slowly moving parallel surfaces of the way or being washed away by cutting fluids.
Their antiwear and extreme pressure properties protect the sliding surfaces.
These oils also protect cast iron and bronze surfaces from rust and corrosion, and are resistant to oxidation to provide long lubricant life.
While on the lubrication subject I’m using grease in all the pin joins with at least 3% moly. The boys operating heavy equipment, think mining shovels, earth movers, equipment costing millions. Use high moly grease on pins and linkages because it stays in place and is formulated for extreme pressures and impact.

[Syd Partridge]

iron Quake, thank you for your suggestion. However I'm unable to find a supplier of Chevron Way Oils in the UK. I will investigate to see if there is a similar product available. Interesting that they protect cast iron and bronze surfaces from rust and corrosion.
I've also found, like you, that molybdenum grease works very well on bearing surfaces. I also like a mixture of plumbago (graphite) and oil.

[iron quake]

Syd, I use Vistac because I have it on hand. A lot of folks with many years of running and rebuilding hammers use chain saw bar oil. I think thats a very good choice as well as it has the tackifires that way oil has. the thing I like about the way lube is the addition of the extreme pressure additives, or at least that's what I'm told. Mobil Vactra in another way oil brand also.

[FieryFurnace]

In my experience, grease slowed my hammer down. I have a Kinyon air hamer with brass guides. There is one guide on each side of the hammer head with the front and back open. I used grease for the longest time. When I switched to oil, there was a NIGHT AND DAY difference in how it operated. It hits faster, harder, and has more control.

It could be different on an electric drive hammer.