Alan Evans Posted November 1, 2016 Share Posted November 1, 2016 7 hours ago, beaudry said: It appears that he has the resume to back up his strongly held opinions whether you agree with them or not . As I said before; ''different strokes for different folks ''. Thank you for the reminder, I posted just before I went to bed this morning, and before I fell asleep I remembered a thread from a few months ago regarding Joel's machines. My input to the thread, you will note, has never been to deny that Joel's Murray will do what he claims. I have spent many happy hours with Clifton's tapes, watching them through at least three times over the years and writing a review for the BABA magazine. I have spent a few hours in the presence of the man himself at a few conferences and have had similar discussions with him. Joel's impressive resume and portfolio however do not back up the non-sequitur of his claim that all air hammers are terrible. You only need to watch the video of JNewman on page one of the thread to see how capable a machine in the right hands that is. Air hammers come in so many different configurations and with so many different intended applications that to group them all together is misleading and pointless. What they share is that they are driven by air. Equally the position that all mechanicals have the same facility as his 240lb Murray is palpably not true. A Federhammer is a mechanical, a Blacker is a mechanical, the smallest Little Giant is a mechanical, a tyre hammer is a mechanical, a Helve hammer....What they share is that they are not driven by air! My argument is not with Joel's hammer's capability but with his simplification to an artificial divide between differently engineered systems irrespective of any capability differences...and the need to rubbish anything. As I said earlier, I also believe know that any hammer is better than none...despite their differences in capability or versatility or appropriate application...they are all an advantage to a blacksmith. Alan Quote Link to comment Share on other sites More sharing options...
Sanderson Iron Posted November 1, 2016 Share Posted November 1, 2016 9 hours ago, Alan Evans said: But whilst picking me up on that you ignored the squeeze issue? Do you still consider the air hammer to have no squeeze? The whip lash acceleration of the Murray on full automatic I would have thought would have very little squeeze compared to an air or steam hammer, the spring is trying to pull the tool back at point of impact rather than push it forward. Yes, the air adds force, and some air hammers can squeeze only, though many air hammers cannot. The first air hammer I worked around, a Chambersburg, could squeeze, and it was handy from time to time. However, nearly all of the work still is done with repeated blows, so most of the forging still has the full-speed problem with tooling. Also, with that machine, it is not possible to gently set the ram down on the work to squeeze it--it still has to tap tap tap its way down, hitting the work multiple times before it finally does any squeezing. I expect that's true of your air hammer too, though I don't know of course. It's not so with a mechanical. I can set the ram of my 100 pounder down on the work or gently push in one movement. Another adjustment on a mechanical, which many people don't use, is the spring tension. Clifton taught most of us that the spring needs to be kept stiff, to give an elastic blow. In my experience, that adjustment is there for a reason, and it's another great thing about that type of hammer. You can change the blow from an elastic blow to a dead blow by loosing the spring. (I'm answering your question, Mr. Evans.) Some hammer manufacturers actually advertised that they made a dead blow (I think the Shaw did) so obviously someone else besides me thinks this is useful. It is particularly useful if you have a hammer without a brake, like LGs came from the factory. You can loosen the spring and hit one blow, and you can push much more easily. This opens up an even bigger window of variation for the mechanical hammer that cannot be approached with an air hammer. All this variation means greater application and usefulness. I hear people argue that with a mechanical you have to stop all the time and change the adjustment. Nonsense. With my 250 I can go from drifting a hole with the tooling stacked 4" high to hitting the work 1/2" thick. It's no problem at all. I can forge a 2" bar (or more) down to a taper 3/8" round without any adjustment whatsoever, and the hammer runs just right for all of it. In fact, it'll hit nice and fast and light for that smaller dimension--just what you want to do. Let's say you're making railing, and you have 40 bars to forge, each with a boss left on the end, which will be turned into, let's say, a fan. You start with a spring fuller to separate the boss, so you want to run nice and slowly and controlled. (I don't know anyone who would prefer to do this operation at a high tappy speed.) Set the hammer to run slowly and light; you're just pushing the tool into the iron. Do all 40 bars, then change the hammer for the next operation, drawing. There's no down time--you're just shifting gears every few hours, mechanically and mentally. It takes as long to get a drink from the fridge. So the next operation is fast and hard, so change the setting. Do all 40 bars. Then maybe you want to swage the base, so you set the hammer to hit fast and light. Do all 40 bars, and so on. This is how these mechanicals were made to be run--in production situations where achieving the most efficient type of blow is possible. No self contained hammer I have ever seen can touch that. Thank you, Beaudry. I appreciate the very nice compliment. P.S. I can answer your questions about the press later if you want, Mr. Evans. This post is getting pretty windy already. j. Quote Link to comment Share on other sites More sharing options...
Alan Evans Posted November 1, 2016 Share Posted November 1, 2016 This post has crossed with yours Joel (sorry Mr. Sanderson, as you are being formal)....at first glance I see we have discussed a similar area...will get back when I have thought about it more! Hammer blows. A couple of things have been going round in my head prompted by this thread regarding the dynamics of various hammer blows. It will be apparent that I am not a physicist or engineer, the basis of my thoughts is more from empirical observation. The description from Joel/Clifton of the forearm squeeze / Murray hammer analogy is problematic for me. My understanding of the process is entirely the opposite. A die stamping drop hammer relies on its speed of impact rather than its weight to pass the energy through the material and fill the die. I am quite happy with the contention that the Murray style whip lash action does indeed cause the effect of the blow to affect further through the workpiece for a given weight of tup and speed of cycle. For this reason this style of hammer can give more bang for the buck....it is not a squeezing action when at its most efficient though. As I described in an earlier post the toggle arm spring is trying to pull the tup back up by the time it is striking on automatic blows, not squeezing it down further. The Murray would not displace anything like the amount of metal per blow when in push/squeeze mode as opposed to full power automatic blows. In that mode it only has the dead weight of the tup, the slipping drive system and the spring power to transmit the energy. A dedicated press working with tonnes rather than pounds is far better equipped to squeeze. The other thing which has been claimed is that the variable speed of the Murray style hammer is an advantage. I have no problem with variable speed...the problem is that the Murray style hammer does it entirely the wrong way around for efficient forging as far as I can tell. If you were able to speed up the lighter blows needed for working lighter section it would be logical. Lighter section material: lighter hammers: more blows per minute. Heavier section material: heavier hammers: fewer blows per minute. Applies whether hand or power hammers are involved. The only advantage of fewer blows per minute on light section I can think of is maybe you have a bit more time to position the workpiece to avoid hitting in the wrong place...but it is so in opposition to the normal forging basis of strike while the iron is hot. In respect of coping with both heavier and lighter section material, being able to vary the weight of the blow rather than the speed is the better compromise I think. It is shared by many (most?) mechanical and air hammer configurations. Alan Quote Link to comment Share on other sites More sharing options...
Sanderson Iron Posted November 1, 2016 Share Posted November 1, 2016 1 hour ago, Alan Evans said: The other thing which has been claimed is that the variable speed of the Murray style hammer is an advantage. I have no problem with variable speed...the problem is that the Murray style hammer does it entirely the wrong way around for efficient forging as far as I can tell. No, you've got it backwards there, Alan. Thats partly what I've been trying, unsuccessfully, to explain. The Murray can run fast and light or fast and heavy or anywhere within its range. In fact, in my illustration above, if you start out with a 2" bar forged to a 1/2" taper, it can hit hard and fast on the thicker cross section and light and fast on the thinner, with the same setting. The speed doesn't have to change at all. I can run the Murray wide open and barely tap a 1/4" round, or I can run wide open and smash 2" round. The spring is doing what your air does--it arrests the motion and turns the ram about for the return. When it begins that arrest is determined by the height of the ram and the tension on the spring, so for heavy blows you set it to leave the energy in the ram. So you see, it doesn't have to be the "whip lash" that you're thinking. 1 hour ago, Alan Evans said: If you were able to speed up the lighter blows needed for working lighter section it would be logical. Lighter section material: lighter hammers: more blows per minute. Heavier section material: heavier hammers: fewer blows per minute. Applies whether hand or power hammers are involved. That is exactly what a mechanical can do. That's what they're made to do. As far as power of a given hammer goes, that just depends on the machine. Clifton came to our shop in the early 90's and ran the 200 lb Chambersburg I mentioned, and he told us at the time that it had more power than his 250 lb Murray. (My, that man can move metal!) A 200 lb Nazel is lighter than the 200 lb Chambersburg too. My 100 lb Hackney doesn't hit anywhere near as hard as a 100 lb Little Giant, because it has a shorter stroke. But we've been talking about control and variation of blow, not power. Joel Quote Link to comment Share on other sites More sharing options...
beaudry Posted November 2, 2016 Share Posted November 2, 2016 I'm not sure how a spring linkage hammer can said to actually push or squeeze the work, but they can be made to momentarily ''dwell '' on the hit at the bottom of the stroke. This should theoretically give a deeper penetration to the force of the blow before the flywheel spring and linkage lift it for the next cycle. By backing off the spring tension on my Beaudry the hammer is able to give a ''dead blow'' with no bounce at the bottom of the stroke, dwelling at full down for a split second before lifting back up for the next stroke . By quickly letting off on the treadle the ram can stay full down on top of the work, but it's not really a squeeze but rather held by the full weight of the ram on top of the work. This dead blow is handy for top tool work and swaging because there is no bounce to the hit. Loosening the spring tension on the Beaudry does't seem to result in any noticeable loss of power in contrast to the Little Giant type linkage. There the spring and toggle arm tension has to be sufficient that the toggle arms are level or pointing slightly up to get the most power out of the hammer. I assume that the linkage on the Murray hammer is basically the same? Is the ability to squeeze or hold the work with air pressure pushing down on the ram inherent in all air hammers or is it a special valving set up just on certain kinds ? Quote Link to comment Share on other sites More sharing options...
Sanderson Iron Posted November 2, 2016 Share Posted November 2, 2016 9 hours ago, beaudry said: I'm not sure how a spring linkage hammer can said to actually push or squeeze the work, but they can be made to momentarily ''dwell '' on the hit at the bottom of the stroke. When I talk about pushing with a mechanical, I don't mean squeezing like a press, with its full power behind it, or like the Chambersburg with air pressure. When you slow a mechanical's ram down, you can push a drift through a hole in one fluid motion; that's what I mean by pushing. That's a lot different than driving it through with a series of fast taps, as you well know, but it's not a squeeze. The Little Giants and Murrays cannot squeeze appreciably. They cannot lock the ram either, at least not beyond the strength of the brake (if it has one) and the spring. A Hackney can lock the ram very securely. It still doesn't give a press-like squeeze, like some air hammers can, but it holds very nicely. (For those who aren't familiar with a Hackney, it's a mechanical air hammer, an atmospheric hammer it has been called, with a variable air spring. It has a brake directly on the ram, which can lock it anywhere in its stroke. Mine has a cone clutch for variable speed.) 9 hours ago, beaudry said: Loosening the spring tension on the Beaudry does't seem to result in any noticeable loss of power in contrast to the Little Giant type linkage. There the spring and toggle arm tension has to be sufficient that the toggle arms are level or pointing slightly up to get the most power out of the hammer. I assume that the linkage on the Murray hammer is basically the same? The level or slightly up rule of thumb is mostly for wide open forging, where the spring has to counter the fast blow. If you want to hit a slower, dead blow, or if you want a little more range of motion (like with a smaller hammer that doesn't have much room) running with the spring looser so the arms are lower is a help. The more you get used to the vocabulary offered by these mechanical variations, the more you can do with your hammer, unlike an air hammer which is caught in just one or two modes. (I just had to throw that in there!) I hope this hammer discussion is helping the Millennial Blacksmith, wherever he wandered off to. Quote Link to comment Share on other sites More sharing options...
nonjic Posted November 2, 2016 Share Posted November 2, 2016 Mechanical hammers slow down when you do a light 'planishing' blow, when if anything you want a light planishing blow to be faster. Air hammers have a constant strike rate. No annoying slowing down when you want to 'round up' a tenon or whatever. I like mechanical hammers, they are efficient little things, but not a patch on a well set up self contained air hammer. Lots of armchair b/s spouted in this thread IMHO. i do think that if someone got a quality 'little giant' type mechanical made in numbers in a low labour rate economy (which should cost buttons) they would still have a place in the market, and sell well. Quote Link to comment Share on other sites More sharing options...
JNewman Posted November 2, 2016 Share Posted November 2, 2016 25 minutes ago, nonjic said: Mechanical hammers slow down when you do a light 'planishing' blow, when if anything you want a light planishing blow to be faster. Air hammers have a constant strike rate. No annoying slowing down when you want to 'round up' a tenon or whatever. I like mechanical hammers, they are efficient little things, but not a patch on a well set up self contained air hammer. Lots of armchair b/s spouted in this thread IMHO. i do think that if someone got a quality 'little giant' type mechanical made in numbers in a low labour rate economy (which should cost buttons) they would still have a place in the market, and sell well. Seems to me I was told there is a company in India making a mechanical hammer. But nobody is importing any. I expect the necessary guarding for first world countries would make adjustment difficult and add to the "buttons" Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted November 2, 2016 Share Posted November 2, 2016 I just saw a CL from Austin TX, USA advertising 25 pound little giants 50 pound little giants 100 pound little giants 250 pound little giants 150 pound Fairbanks 400 pound Beaudry Quote Link to comment Share on other sites More sharing options...
Sanderson Iron Posted November 2, 2016 Share Posted November 2, 2016 2 hours ago, nonjic said: Mechanical hammers slow down when you do a light 'planishing' blow, when if anything you want a light planishing blow to be faster. Air hammers have a constant strike rate. No annoying slowing down when you want to 'round up' a tenon or whatever. That is blatantly false, nonjic. That is a myth propagated by the air hammer salesmen and air hammer enthusiasts who do not understand how mechanical hammers operate. A mechanical LG style hammer can hit lightly as fast as it can run. I will give yet another simple example: It is possible to raise the ram of a LG mechanical so that when it is run full speed, the dies barely touch. Did you know that? If you raise the ram 1/2", it will barely touch a 1/2" thick bar. That means a very light blow. Understand? Now if you put a 2" bar between the dies and hammer it wide open, it will hit very hard, with powerful dead blows. If you're drawing that bar down to a taper with a 1/2" end, by the time you get to the smaller end, you'll be hitting fast and light again. Does this make sense? Fast and light on small section, hard and dead on the large section--all with the same hammer setting--just like it should be. You might like an air hammer, and that's fine, but facts are facts, and air hammers do not offer as much variation in the kind of blows they can make. They're one speed, and whether you like one or not, that limits what kind of blows they make. 2 hours ago, nonjic said: Lots of armchair b/s spouted in this thread IMHO. I'm not sure what armchair b.s. you're talking about, and your blanket statement kind of insulted everyone here at once. Everything here should be pretty clear even to an air hammer operator who has never run a mechanical--if in fact he runs a hammer at all. We don't know all the people here, so I think we should give everyone respect in the benefit of the doubt. Quote Link to comment Share on other sites More sharing options...
Glenn Posted November 2, 2016 Share Posted November 2, 2016 2 hours ago, nonjic said: Lots of armchair b/s spouted in this thread IMHO. Could you please specify the armchair b/s so we can discuss those items to clear up any mis-information? Please site your sources of information so it is no longer a personal opinion but a discussion of facts. If you have operated THAT specific hammer or type of hammer then please say so and we will take your experience as a reference. Quote Link to comment Share on other sites More sharing options...
Judson Yaggy Posted November 3, 2016 Share Posted November 3, 2016 nonjic (John) owns Massey Hammers. He is widely recognized as one of the leading experts on power hammers in the world. Quote Link to comment Share on other sites More sharing options...
Sanderson Iron Posted November 3, 2016 Share Posted November 3, 2016 14 minutes ago, Judson Yaggy said: nonjic (John) owns Massey Hammers. He is widely recognized as one of the leading experts on power hammers in the world. I believe a Massey hammer would be an air hammer. Apparently not so versed in mechanical hammers. Quote Link to comment Share on other sites More sharing options...
beaudry Posted November 4, 2016 Share Posted November 4, 2016 Mostly, the armchair BS are just opinions presented as fact. I've seen some fantastic artistic work done on air hammers and they seem to be the hammer of choice in production and industrial shops. One thing they seem to have that no mechanical hammer has, is the ability to upset a piece down from near the top of their stroke and then work it on edge with no change in setting. That seems to open up a wide range of possibilities to be able to bump up stock to fit the job and to get really radical changes in section. Am I right that they have the capacity to develop full power from the top of the stroke or is the travel speed of the ram integral to the power of the blow ? If I won the lottery, I'd have a shop with the room and the power to have a 300# Massey, Nazel or Chambersburg pneumatic, a 200# Beaudry motor driven mechanical and a 25# or 50 #Little Giant type hammer. I have the latter two already. It's unlikely I'll win the lottery, so in the meantime I try to get the very best performance from the machines I have and am always interested to learn more. I bet that 400# Beaudry listed up thread is a real pile driver. Quote Link to comment Share on other sites More sharing options...
Sanderson Iron Posted November 4, 2016 Share Posted November 4, 2016 8 hours ago, beaudry said: One thing they seem to have that no mechanical hammer has, is the ability to upset a piece down from near the top of their stroke and then work it on edge with no change in setting. That seems to open up a wide range of possibilities to be able to bump up stock to fit the job and to get really radical changes in section. Very true. To upset very far with my hammer, I have to change the ram height as it gets lower. Of course, you can get around these problems by working downwards with tooling (like grooves or bolsters in the lower die and so on) or upwards with blocking. A friend of mine has a bottom die with grooves on his Bradley, so he can hit a bar flat and then stick it down in the groove in his die to hit the edge, all with one setting. You don't have to jump through these hoops with an air hammer. 8 hours ago, beaudry said: Am I right that they have the capacity to develop full power from the top of the stroke or is the travel speed of the ram integral to the power of the blow ? Any I have run has less power at the top of the stroke. The ram just cannot get its speed up, since there is less movement or stroke. In comparison, a LG can make a full stroke, full cycle, with full power, all the way to the top of its setting--as long as you're working within its capacity, of course. I expect your Beaudry does too. 8 hours ago, beaudry said: ...air hammers...seem to be the hammer of choice in production and industrial shops. I think the Bradley guys would disagree with this! The more versatile your shop is, the more diverse your work can be of course, so your dream of having lots of hammers is a wonderful idea. I suppose if a person had the room and money, an air next to a mechanical would be a good combination, but you'd have to be good with them both. It's kinda like a rifle: a man with one rifle usually is a better shot than the fellow with a collection of rifles, with one for any occasion. Of course, here I am with three hammers, so I really shouldn't talk. Quote Link to comment Share on other sites More sharing options...
JHCC Posted November 4, 2016 Share Posted November 4, 2016 10 minutes ago, Sanderson Iron said: Of course, here I am with three hammers, so I really shouldn't talk. I would be happy to relieve you of one of those, if it would make your life easier. Quote Link to comment Share on other sites More sharing options...
kubiack Posted November 4, 2016 Share Posted November 4, 2016 8 hours ago, beaudry said: I bet that 400# Beaudry listed up thread is a real pile driver. I had the owner send me some pictures of it and some of the other hammer he has for sale. However the Beaudry is a bit of a mystery. The model number that is cast into the frame appears to be NO 45 which does not match any of the models that they made. I was really hoping the owner was wrong and it was a 100 or 150 pound hammer but he is certain that it weighs over 9000 pounds which would make it a 500 pound hammer. At any rate I'm going to go see the hammers sometime in the next few weeks. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted November 4, 2016 Share Posted November 4, 2016 I know a professional smith out here with a 25#, 50# and 100# LG, an Erie steam hammer converted to compressed air and a 200# Chambersburg. (he had a 1000# chambersburg and a 2000# chambersburg out in the bone pile last time I visited) Each had features that they were the *right* tool for a specific job. The collection makes me whimper a bit... Quote Link to comment Share on other sites More sharing options...
nonjic Posted November 4, 2016 Share Posted November 4, 2016 Massey made many hundreds, possibly thousands, of 'mechanical' hammers in many different configurations and designs. edit, They pretty well stopped making them as the air hammers did everything the spring hammers did, and a lot more. The ability to work at any point in the hammers stroke without making adjustments made them much more versatile for the use of tooling, knocking down 'high' workpieces into pancakes, before using a punch etc, before putting a saddle in and ring forging, using swages of different heights etc etc. Quote Link to comment Share on other sites More sharing options...
beaudry Posted November 5, 2016 Share Posted November 5, 2016 nonjic I've heard that Massey did indeed make mechanical hammers. I would imagine that they filled the same niche they had in the US of a relatively lower cost machine that could run on less power in a rural or small town blacksmith shop. Do you have any pictures from the Massey archives to share ? Do you know if many Massey hammers [ pneumatic or mechanical ] were imported to North America ? Quote Link to comment Share on other sites More sharing options...
Alan Evans Posted November 7, 2016 Share Posted November 7, 2016 On 02/11/2016 at 10:24 PM, Sanderson Iron said: It is possible to raise the ram of a LG mechanical so that when it is run full speed, the dies barely touch. Did you know that? If you raise the ram 1/2", it will barely touch a 1/2" thick bar. That means a very light blow. Understand? Now if you put a 2" bar between the dies and hammer it wide open, it will hit very hard, with powerful dead blows. The whip lash blow must generate the maximum impact, as the elbows are coming closer together, and the tup is at its fastest. If in your example that optimum speed was achieved at 2" then `I can see that any blows on smaller dimension workpiece would be less powerful. The tighter the spring and the more rigid the toggle arm connection the slower the actual strike speed would be, irrespective of the blows per minute speed. Yes, more squeeze by slipping the clutch or deflecting the spring but less actual hot metal moved. The more rigid the link between crank pin and tup becomes, the less the maximum impact; the tup will actually be slowing rather than accelerating as does the vertical movement of the crank pin turning through the lower quarter of its revolution approaching BDC. I understand what you have been saying about the Murray's blows having less effect as the workpiece dimension reduces....and thus enabling you to keep the pedal to the metal and maintain your maximum BPM rate, with lighter blows on the workpiece as the tup runs out of stroke. Provided that the required dimensions of the workpiece comply and with the general tolerance of the live forging process I can see it could work well. In common with most hammers: hand, air, water or electro mechanical configurations the maximum impact of the Murray must occur with the tup cycling at its fastest speed accelerating over its longest stroke. This must be set to the size of the bar to be worked or a compromise made to maybe a third or half-way between the start and finish dimensions. Of course with the tolerance built in to the system this is not a deal breaker. But does mean you have to consider your processes well in advance and prepare the hammer accordingly to get the most out of it. The advantage with the air hammer is that you are in precise control of the weight of the blows without any concomitant loss of BPM, rather than the more nebulous relationship of BPM and blow weight when taking pressure off the pedal on the Murray. So using your dimension/taper example...any air hammer could generate fast heavy blows on the 1/2" section or anywhere in between...the Murray will not allow you to have heavy blows whether fast or slow on the thin end, without resetting. What I was musing about was a machine having the ability to actually increase the speed above that which is optimum for full power blows whilst simultaneously reducing the impact power. But as it stands I think the Air hammers have the most useful compromise for free forging. Apart from prompting an interesting discussion and learning about the strengths and weaknesses...I hope the OP has learned as much as I...my main argument has been with your "they're terrible machines" comment. I enclose some images of "mechanicals" which do not have the control or versatility of your 240lb Murray and some self contained air hammers that have considerably more! Alan On 04/11/2016 at 4:19 AM, beaudry said: Am I right that they have the capacity to develop full power from the top of the stroke or is the travel speed of the ram integral to the power of the blow ? Air hammers do only tap with their tup weight at the top of the stroke. Like all hammers...hand or mechanical they rely on the acceleration over their stroke to generate maximum impact. Otherwise they would be called presses. There is a huge difference however between the top of the stroke and the rated capacity of the hammer. My single acting 3cwt Alldays has a stroke of 18" but is specified to have a regular working capacity of 5" round material. You can hit a tool or a workpiece 18" above the bottom pallet but it will just effectively be with the weight of the tup plus a couple of atmospheres maybe 350kg (700lb). But I have happily upset pieces which were 10" high at the outset. Double the rated capacity and in the top half of the stroke. While it is true that the maximum blow an air hammer can generate is when the pallets meet…It does not follow that the upper end of the stroke is useless...it just keeps getting better the lower and faster it goes. Alan Quote Link to comment Share on other sites More sharing options...
beaudry Posted November 7, 2016 Share Posted November 7, 2016 Alan, thanks for your reply clarifying the power available at the top end of the stroke of an air hammer. Really love seeing pictures of your work by the way and your valuable contributions to the forum. On an unrelated topic , are you using an acid based pickling paste to treat your stainless steel forgings and is it effective to preventing rusting on forged stainless work exposed to a damp climate ? Here in the US it's customary to use an proprietary acid based cleaning paste to keep rust from forming on the heat affected zones of welded stainless steel pieces but I am not sure of it's actual composition and if it would be effective on SS forgings . It's fairly hazardous to handle and must be thoroughly rinsed from the piece before being put in service. The increased expense of the base material and general extra challenge of doing anything with stainless must be offset by having reduced or no finishing or maintenance costs ? Quote Link to comment Share on other sites More sharing options...
Sanderson Iron Posted November 7, 2016 Share Posted November 7, 2016 1 hour ago, Alan Evans said: my main argument has been with your "they're terrible machines" comment. Okay, so can I say they're ugly? Really ugly? Will that make fewer people mad? And I agree that there are a lot of mechanicals which are not as versatile as a Murray. I have tried to specify "Little Giant" (LG) style hammer in my discussion. That design is one of the best configured and efficient hammers ever made, and it can do things, make movements, that no self contained hammer can ever do. 1 hour ago, Alan Evans said: The tighter the spring and the more rigid the toggle arm connection the slower the actual strike speed would be, irrespective of the blows per minute speed. Not quite true. The spring gives the ram a snap at the top of the cycle, throwing it downwards for the next blow. If your workpiece is tall enough to be, say, midway in the cycle, you can have a very fast "actual strike speed" (feet per minute)--faster, in fact, than with a weaker spring setting which wouldn't give it that fast return. On the other hand, if you want to strike a single dead blow, loosening the spring so that it does not arrest the ram at the bottom of the cycle can result in a harder single hit. 2 hours ago, Alan Evans said: Air hammers do only tap with their tup weight at the top of the stroke. Like all hammers...hand or mechanical they rely on the acceleration over their stroke to generate maximum impact. Otherwise they would be called presses. Yes, but there is a very significant difference between how a mechanical hammer and an air hammer tackles this problem (of hitting a tall object). You see, an air hammer has a more or less fixed cycle--it can't be raised or lowered--so all it has to work with is the stroke in that one cycle position. That's why it can't get its speed up and is weak on the top. A mechanical can raise its cycle. This lets it hit high or low with equal movement and full power. 1 hour ago, Alan Evans said: So using your dimension/taper example...any air hammer could generate fast heavy blows on the 1/2" section or anywhere in between...the Murray will not allow you to have heavy blows whether fast or slow on the thin end, without resetting. True. I gave that example to illustrate to our friendly Massey Dude that a mechanical is perfectly able to hit light fast blows, and that sometimes that happens automatically, all with the same setting. Keep in mind, "fast blows" is all the air hammer is capable of doing. The ability to be adjusted in order to get different kinds of blows--other than fast--is one of the many virtues of a mechanical hammer, as I have said before. Some people confuse versatile with convenient; but of course, if you can't make the machine do what it's capable of, it's not as versatile as it could be, so it's tempting to trade versatility for convenience. That's what air hammers do, but at a huge sacrifice. Quote Link to comment Share on other sites More sharing options...
basher Posted November 7, 2016 Share Posted November 7, 2016 I think that I am finally getting some of whats being discusses here . I have seen youtube videos of german smiths running 200lb+ federhammers and punching with very slow strokes. none of my mechanicals have had the weight to do this very well (my 90lb kingshorn bow spring hammer has a huge range of travel and gets close). However I can do a great job of replicating this with 2 of my air hammers one with speed controle and one with variable pressure/vaccuum, although the variable vaccuum still runs at the same bpm. However in reality I would use a press for this job. I think that the versitility that you are claiming for mechanical hammers is such a specific versitility that it creats a bit of a dichotomy. I do not believe that a lot of people would consider that having to re-ajust and retool a hammer to achieve a possibly larger overall range of distinct specific and limited use is infact more versitile. At least for most of us. Having run power hammers for 22 years now ,I am constantly impresses by the diferent ways people use and run them, I have certainly learned a lot over the last 15 years from people who are much more varied (or indeed specific) in their hammer uses. and the tool has changed for me from a machine for bashing out tapers to somthing much more versitile. there is a lor more to learn still. Quote Link to comment Share on other sites More sharing options...
Alan Evans Posted November 7, 2016 Share Posted November 7, 2016 (edited) 16 hours ago, beaudry said: On an unrelated topic , are you using an acid based pickling paste to treat your stainless steel forgings and is it effective to preventing rusting on forged stainless work exposed to a damp climate ? Edited November 7, 2016 by Alan Evans sorry stupid software will not let reply for some reason. Short answer most projects I have passivated and /or electro polished. I have used pickling paste. Yes it works. Nitric and Hydrofluoric takes no prisoners, eating through flesh to bone. Quote Link to comment Share on other sites More sharing options...
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