Warming up the self contained power hammer on cold days. Is this normal?

[Fe-Wood]

I picked up an Anyang 33 this summer. I'm finding as the weather gets cooler it needs to warm up before it will work. I have to let the hammer run for up to 15 minutes before it will hit the work with any force at all. Sometimes as I push the treadle, it will blow air past the rings of the driven ram and not move at all. If I slowly press the treadle I can run the tup down for a ways without smacking dies. It just cycles up and down about 1.5"

 

This is what I know so far-

•I bought the hammer used. It was made in 2011. It saw very little use from the previous owner.

•I did not get an owners manual with it.

•I'm using 30w non-detergent oil for lubrication. Oil consumption is good. The driven ram is wet without being soaked and dripping profusely.

•On the coldest days I need to fully depress the treadle to aid in start up. If I don't, the motor lags badly.

•I have spoken with James Johnson about it and he said this is normal with the smaller Anyangs.

• The valve arms seem to be factory pinned to the valve shaft. I have tried adjusting the connecting rod between the valves to see if that helps. It seems I was able to make it hit a little harder with no change to the cold running problem.

 

Any ideas on how I can fix this problem?

Thanks!

[nonjic]

Hi,

 

This is quite a simple one to sort :) (only took me about 3 years to work it out......)

 

basically, in a nutshell, the 15 kg (33lb) hammers run much better on a very thin oil, like a 10w hydraulic. (iso 32).

 

They do not have enough reciprocating mass to overcome the drag of a heavier oil when they are cold.

 

Sometimes they 'gum up' a bit inside if a heavier oil has been used. If you remove the 2 top cylinder covers you can give the bores a wipe out with some diesel (or whatever). Be sure to put the compressor piston cover back on in the same position. Put a wipe of the thinner oil into the bores once you have wiped out with cleaner, before you put the lids back on.

 

If you are going to use a thinner oil I strongly recommend modifying the oil feed system by putting a good quality non-return valve in the line, and a needle valve to meter it better. The set up from the factory (IMO) does not have enough finesse to meter the lighter, lower viscosity oil.

 

I understand that James sells an oil metering kit that can be retrofitted to hammers that he has not supplied.

 

I have not noticed any adverse effects on the wear rate of any parts of the hammer using a lighter oil.

 

The small hammers will still be a little slower to start making full power when they are cold, but the use of a thinner oil makes a big difference.

 

Hope this helps :)

[Fe-Wood]

Thanks nonjic!

I was thinking about using thinner oil. My hammer has an inline needle valve now. I assumed it adjusted the oil coming into the top of the drive piston so it could be "pushed" into the driven piston. Am I wrong in this thinking? Is there another oil inlet going directly into the piston from the reservoir itself?

 

I am also thinking about adding a way to make the hammer cycle the driven piston at about half stroke during warmup. Do you do anything like that?

[forgemaster]

It seems like every time almost that we have hammered at Moonies we have to take his An yangs apart and clean the burned up crud and glaze from his valves etc, he never seems to have a problem with them, but maybe its just the interval or maybe he perseveres with it in the knowledge that Phil will be down next month and he will take these apart and clean it all for me.  Seems as John said to come from the heavier oil, we as John suggested also wipe it all out with dieso.

 

Phil

[nonjic]

I stick a timber wedge under the back end of the footlever to get the ram 'swinging', but not striking, to assist the warm up.

 

If you have an inline metering valve Im guessing James has already modified the hammer.

 

The oiler works on a vacuum from the compressor piston on its down stroke, and the check valve stops air being blown into the oiler on the piston upstroke.

[MLMartin]

What about wrapping the head of the hammer with one of those heater cords? Like the one used to keep a engine block warm.

 

I am not familiar with the oil reservoir of this hammer. Could you insert a oil heater into the reservoir chamber? I know some large equipment in cold areas have this part.

[Jamesrjohnson]

Fe-wood… Your hammer is fine, its just a new hammer that has probably not been run very much and is "tight" from the factory, like a new car engine.  I think a car engine is a good analogy.  When you have a new car or rebuild a car engine, you should run lighter oil, and it takes a while to "seat" the rings and loosen the engine up. Anyang hammers are made with tight tolerances and that is a good thing.  Over the years we have made a lot of positive changes to Anyang USA but I would never want the factory to reduce their tolerances, just so the customer doesn't have to break in there hammer. In fact, I have had emails and phone calls from customers that tell me they were surprised to find their hammer hitting harder as they got more hours on them.
 
I do agree with Nojic lighter oil in cold conditions is a good idea.  I think I remember mentioning that over the phone. If I didn't I'm sorry.  For my northern customers I usually recommend 10wt especially if your shop is not heated.
 
I don't recommend taking the hammer apart just to clean.  In the past,  I've had customers that have dismantled the ram, the valves, and the compressor side of the  hammer all because they thought that it needed it ..  When all they had to do was put in fresh oil and set up the treadle so that the ram lightly cycles.
 
(you can set up your 33lb so the ram lightly cycles by adjusting the turnbuckle on the side of the hammer, then placing a weight on the treadle)- takes about a minute.
 
Ive set up hundreds of these hammers.  The hammers that are delivered from the factory will have thick oil left from the original assembly as well as a ram coated in cosmoline..   i would never take these hammers apart, just to clean.  Its really simple, flush the old oil out with fresh oil (in cold use 10wt) and cycle the ram.   With the valves that i install, with the oiler turned up, these hammers are self cleaning.  The new oil check valves and flow control valves work well with thin 10 wt. oil as well as thicker oil. 
 
I would also not recommend trying to modify the valve timing.  The upper and lower valves are adjusted to be in sync with each other.  I run each hammer before I deliver it and make sure that the timing is good and the hammer is running 100% the way it should.  When you get an Anyang hammer, the most you should have to do is anchor it to the floor, plug it in, and start hammering. 
 
If you have any other questions, please call me.  I am always available to answer any questions. 
 
James R. Johnson
940-627-4529

[nonjic]

They do improve as they bed. The 33lb ive kept for myself is around 6 years old, and has received a fair bit of use being lent out, demo hammer etc. nice and snappy from the treadle now :D

[Fe-Wood]

Hey James- 

I'm very happy with the 33 overall. It is doing what I want and doing it well. Its only now as it is getting colder that warm up has become a problem and its only just beginning. I'm going to try the lighter oil and see how that works (James, you may have mentioned that but I forgot). I think I'm going to make a little jig of some sort to hold the treadle partway down so the driven piston is cycling more.

 

Thanks everyone for all the suggestions and responses-

[jeremy k]

You may be just experiencing (along with a bit thick oil) a hammer that hasn't been fully broke in yet - sounds like you got a fresh one - good for you!!!

[Fe-Wood]

Jeremy,

When I first started running this hammer hard it had that new hammer smell... Didn't hardly look used when I got it :) and the dies were fresh! :wub:

[Fe-Wood]

So I'm ready to replace the 30w oil with 10w oil and I'm not finding just straight 10w oil around here. There was the mention of 10w hydraulic oil. What about ATF fluid? What other oils are people running?

 

At present, I have to run the hammer a good 1/2 hour before it develops enough power to move hot metal.... Seems excessive to me....

[jeremy k]

sounds like you got your self a sweet deal then - just keep using it with a smile

[metalmangeler]

1/2 hour sure sounds like a lot to me also. How cold are you talking? In the winter I prewarm my air compressor and tumbler with a small area heater like a milk house heater. I normally only do this when it is 0 f or colder. 

[Fe-Wood]

The temps here lately have only been in the high 20's low 30's and it ain't even cold yet! 

[forgemaster]

Just had Hammered at Moonies weekend gone, you better believe it he had to pull the valves out of the Anyang to clean the bores up again, note to any one else, do not use a cylinder hone to clean the bores of where your valves go, on your anyang, little pieces of the honing stone will break off as they go past the ports and drop down into the port, and they take a long time and much fussing to get them out again, don't ask the Moon how he knows this now.  I reckon either a flap wheel in a die grinder or a swizzle stick with some emery cloth in the electric drill would have worked better, and with no broken stones to fall down into the ports.

Phil

[iron woodrow]

how many beers did it take to get the bits out phil?

[kasper]

I have 33lber its used daily,for a little hammer their a work horse,but need a little warm up time,if I'm going to use the hammer and she cold I give the hammer about 15min warm up time,by doing that she hits hard right from the start.I use 30wt oil yr round and it does get cold here in B.C Can, the idea of 10wt is a good idea,.........happy hammering .........cheers

[Fe-Wood]

forgemaster-

You might think about putting a filter on the air intake below the crank shaft, I am. Might save some time for more beer drinking at the hammered....

So this morning I went out to start forging and it was a full 45 minutes of warm up run time before I had full forging power. That just ain't right!

[peacock]

If you are letting it idle the short stroke will not warm the hammer much.  To warm up an air hammer it does the most work when it is stroking as long as possible without hitting the dies. My Sa mak  takes about 5 min. at 20 degrees to warm to the point I can do useable forging. 10 more min. of light forging and it's full power. I am working on a dual oil tank set up with ATF in one tank and 30wt. it the other. Seem to work if I turn off the 30 wt. and on the ATF about 10 min before I quit forging at the end of the day.  Start up the next morning is on the ATF for 1 or 2 min switch back to 30 wt.  So far so good. A light bulb very close to the oil tank also helps.

[Fe-Wood]

Peacock,

I have a block with various shims to hold the hammer at as full a stroke as I can get w/o slapping dies. 

[nuge]

I had the same hammer, same issue. One thing that I was told as a last case was to chamfer the rings. Not being fluent on the insides of air hammers I chose not to investigate this option. It was my only hammer at the time which made the warm up time (about twenty minutes) unbearable so I chose to trade up but man when that little guy got going it would really hit. Another fix may be to rig up a heat blanket around the pistons. My current hammer is a 40 kg striker and it actually has the opposite problem. On hot days I get about an hour of hard work before the pistons get too hot and the hammer gets a little erratic. I was thinking maybe a brassiere filled with ice packs. Who wants to forge when it's 95 degrees out anyway? I think your best bet might be to feed it as much steel as possible, repeat. It does get better.

[Wroughton]

I have the same oil problem with 55 lb Stryker. I don't like the 10wt fix. I spend more time controlling oil feed once the hammer warms up than I do forging.

 

Last winter I kept an infrared spot lamp pointed at the hammer base. Put it on a timer that turned on a couple of hours before work. I've imagineered a foam box to fit over the hammer to keep it warm at night with a small incandescent bulb. Not built yet but at the rate we're going this fall it's coming soon. 

[Fe-Wood]

nuge,

good choice not to grind a bevel on the rings!!!!! Seems counter productive.

 

I'm thinking I might have to use some heat tape to keep it warm. Wroughton, putting it on a timer is a great idea! I'll likely throw a packing blanket over it too.

The part I don't like is that I have to turn on the hammer, let it run and adjust the blocks to keep it cycling for about 45 minutes. The noise sucks and so does the waste of power not to mention the wear on the hammer.

[jeremy k]

Changing to a lighter oil did not help?