Cylinder to tup connection

[youngdylan]

Generally there is a tapered socket in the ram and a taper on the end of the rod.

ah ha

[youngdylan]

I'm all for a new thread discussing the 'new Kinyon'. Are there pictures?

Bob

HWHII has posted some in the thread "narrowing the PH field". Looks intriguing

[SGensh]

When I reconfigured my homebuilt air hammer I used a system much like Don and Grant are suggesting. I'll try and attach two photos of the connection which has served me well. (I used a similar setup on the first iteration also). The threaded rod of the air cylinder runs into a tapped hole in an aluminum block the same size as my ram. It is prevented from rotating by a clip which is in turn held by one of the four bolts which pass through this block and teh one below it into tapped holes in the 90 pound ram. The bolt holes in the blocks are oversized to allow deflection and each layer is seperated by a piece of conveyor belting. There are "washers" of the same material under steel washers at the bolt heads. It is dead simple, cheap, and it's worked out well for years. I've never broken a rod with this arrangement though I did detach the piston once. Steve G

[Nakedanvil - Grant Sarver]

Hellferstout! (That's a Norski name, like in Andrew Hellferstout). Looks like you got a connection with enough give, very cool, thanks for sharing. Guess that's another (-) for youngdylan. :P

[Judson Yaggy]

Here's what I did, but it looks like Grant and Steve G. beat me to it, not surprising. I didn't make my connection as massive as Steve's, I used 1/2" plate thruout. Drawing is section thru tup and connecting plates, washers etc. not shown. flex connect.pdf

[youngdylan]

Hellferstout! (That's a Norski name, like in Andrew Hellferstout). Looks like you got a connection with enough give, very cool, thanks for sharing. Guess that's another (-) for youngdylan.

Hey, I'm collecting dontcha know

[youngdylan]

I LIKE this forum, its real useful .....

Brownie points all round to Grant Steve G and Judson.

Kinda looks like there's mileage in spring/spring or rubber/rubber system. Till now, I'd just accepted the cylinder rods as essentially consumables.

Been planning to revamp my Kinyon sometime using twin "pushing" cylinders besides the tup guides. I might now go for using a tup in box section + UHMW bushing (as per bigBLUR) and have a play with the spring/spring thingy.

On a related topic, has anyone got any views on using a real long, say 4 or 6" rebound spring so the tup slams into it soon after passing the pilot, it stores a lot of the "up" energy then returns it on the down stroke. My limited way of thinking wonders if it would shorten the up part of the stroke (hence speeding the cycle rate) but still allowing a long enough down stroke to develop ooomph.

[John Larson]

In my opinion a jointed cylinder is better than a solidly mounted cylinder. Massive old steam hammers without joints seem to have worked, however. Without adequate alignment precision there will be problems. I have used spherical rod ends and found the body stretched and the ball became loose. Heavier duty spherical rod ends can be used with less or no stretching. But you still have the tolerances between the cross-bolt and the bore of the ball which allow click-clack noises. I've never cared for that noise. I eliminate it in my joints. I use a 2" ball on the end of the cylinder rod and capture it between two hemisphers that can be bolted together to eliminate all slop. On the top of the cylinder I use a 2-axis pivot analogoue to a truck U-joint where again tight bolting eliminates slop. My joints offer flexibility, but they are quite stiff.

In personal conversation with Ron Kinyon he said that the life of one of the flexible alignment couplers is limited. Also they are quite a loose joint and the click-clack noise can be an issue, at least eventually.

Under reciprocation, there are forces that try to unscrew cylinder rods. I now use factory pinned pistons and C-clip the rod to its mount.

[youngdylan]

In my opinion a jointed cylinder is better than a solidly mounted cylinder. Massive old steam hammers without joints seem to have worked, however. Without adequate alignment precision there will be problems. I have used spherical rod ends and found the body stretched and the ball became loose. Heavier duty spherical rod ends can be used with less or no stretching. But you still have the tolerances between the cross-bolt and the bore of the ball which allow click-clack noises. I've never cared for that noise. I eliminate it in my joints. I use a 2" ball on the end of the cylinder rod and capture it between two hemisphers that can be bolted together to eliminate all slop. On the top of the cylinder I use a 2-axis pivot analogoue to a truck U-joint where again tight bolting eliminates slop. My joints offer flexibility, but they are quite stiff.

In personal conversation with Ron Kinyon he said that the life of one of the flexible alignment couplers is limited. Also they are quite a loose joint and the click-clack noise can be an issue, at least eventually.

Under reciprocation, there are forces that try to unscrew cylinder rods. I now use factory pinned pistons and C-clip the rod to its mount.

John

Do you have any experience of rods snapping at the tup to rod connection. As said I, do beast my hammer, often with cold work and I guess it's the shock waves combined with the stress risers around the machining of the thread that does for it. Do you have any opinion on using some sort of "isolation" coupling at the tup/rod connection, or does your proprietary cylinder mount address this issue?

[JNewman]

When I origonally built my hammer I used an old hydraulic cylinder with a clevis on the end. The clevis clacked all the time with the small amount of clearance in it. It broke several times always in the middle of a rush job, I would weld it back together and get it back to work. After I moved into my current shop I replaced the cylinder with a used bigger air cylinder(smaller rod). With the new cylinder I was very carefull to get a very accurate alignment although it is a rigid attachment. I (ab)used it quite a while before the rod broke where Youngdylan's are breaking, I ordered a new rod but the job I was rushing on was for a big machine shop and they re threaded the rod for me. It has not broken yet but I am glad I now have a spare on the shelf. I do not do a lot of cold work but I was using the hammer hard, swaging larger alloy steels etc. Now that I am only using the Kinyon for lighter work I think that I may never use that spare.

While I think that the custom built flexible/rubber couplings may add life to the rod ends I think that not having "slop" in the system is as or even more important. Even though the steel sections were bigger with the hydraulic cylinder, the ram was double the weight with the new cyliner and I had much more flexibility with two clevises, I broke the clevis much more often than with a rigid setup.

Almost every time the clevis broke it was the steel clevis breaking not the weld.

[Mainely,Bob]

I`m still wondering why there was a leaf spring incorporated into this connection on these new hammers.Perhaps this is the answer to the tight yet flexible connection problem.
The pics show little space on the spring between the yoke attached to the cylinder rod and the tup so there can`t be much flex taking place between the two.All the flex must be taking place in that long span between that yoke and the anchor point at the top of the frame.

[monstermetal]

I know this is not what is on your guys minds... but I had a thought today (im not saying it was good, just that it was a thought)

What about using a double ended/rod double acting oversize cylinder? Maybe such a thing is not available off the shelf... But it seems to me that if you had a 12" travel (overall length would be over 36") and either end of the rod was connected to the tup via a soft connection of some sort, you would have twice as much cylinder bushing to guide the rod and twice the connection point. The other plus is that because the rod would displace area on the back side you would have a balanced system, you could use a 3.5" or 4" bore and still have a quick action because of piston volume loss... It seems like using a chunk of 6" X 2" by 40" long for a ram so the rods could mount to either end would work slick, Seems to me this would solve lots of issues???

Grant, tell me why this isn't a good idea??

[Nakedanvil - Grant Sarver]

Well, by my calculations the machine would then be 19 feet tall! Other than that it sounds good.

[youngdylan]

Now that I am only using the Kinyon for lighter work I think that I may never use that spare.

While I think that the custom built flexible/rubber couplings may add life to the rod ends I think that not having "slop" in the system is as or even more important. Even though the steel sections were bigger with the hydraulic cylinder, the ram was double the weight with the new cyliner and I had much more flexibility with two clevises, I broke the clevis much more often than with a rigid setup.

Yeah that kinda solved the issue for me I guess, I do the heavy lifting with my Anyang and use the Kinyon and KA75ish for speciality dies or with real small radius fullers (20mm) that you just don't pound with. That said, I probably spend more time on the Kinyon than the Anyang, I tend to use a lot of speciality dies rather than spring swages/fullers and its real easy to knock them up for the Kinyon.

I can see that "slop" in the connections would be fatal, there'd be a constant hammering action due to clearances. I was kinda wondering about some some sort flexible but "no slop" coupling. I like Grant's idea of using a "spring spring thingy" as per the KA75, but around the rod connection, might have an experiment if I ever have the time.

I haven't done much cold work recently and haven't had a breakage in a while .... are these facts connected? I tend to do cold work on the Kinyon because it's inconvenient but not the end of the world if the rod breaks. If I used the Anyang and the frame cracked I guess I'd be a little more p***ed.

Grant, I notice on some of your you tube videos you demonstate the hammers by banging the dies together with nothing between them, are they hammers bullet proof enough for this not to be an issue?

[youngdylan]

I`m still wondering why there was a leaf spring incorporated into this connection on these new hammers.Perhaps this is the answer to the tight yet flexible connection problem.
The pics show little space on the spring between the yoke attached to the cylinder rod and the tup so there can`t be much flex taking place between the two.All the flex must be taking place in that long span between that yoke and the anchor point at the top of the frame.

Yeah too short for flex but if he used rubber bushes ?????? The type that are used in and around truck suspensions

[monstermetal]

Well, by my calculations the machine would then be 19 feet tall! Other than that it sounds good.

I think I could do it in under 15 feet ;)

[JNewman]

I don't like the idea of the spring in the new Kinyon design. I much prefer Steve's, Grant's and John's solutions. The wonderfull thing about a regular Kinyon type hammer is it's simplicity. Adding the leaf spring adds a bunch of extra moving parts, (which need to be guarded if you are running a commercial shop) and adds a bunch of places you can start to build up slop in the system. The only significant advantage I can see with the spring setup is for those with low ceilings.

[youngdylan]

I don't like the idea of the spring in the new Kinyon design. I much prefer Steve's, Grant's and John's solutions. The wonderfull thing about a regular Kinyon type hammer is it's simplicity. Adding the leaf spring adds a bunch of extra moving parts, (which need to be guarded if you are running a commercial shop) and adds a bunch of places you can start to build up slop in the system. The only significant advantage I can see with the spring setup is for those with low ceilings.

Point taken,

I really love the simplicity of the original but the rod/tup connection defintely is a weak point. The off centre guide is another weeak point. In early day It had the plate on the back of the tup shear of from the tup. The new gude, or the bigBLURGGH style, is a definite improvement The cylinder pulling instead of pushing (so better balanced/ more controllable) is also a definite plus.

I only came across the design a few days ago so am still am getting a measure of it.

[peacock]

Some Bradley hammers use a rubber cushion for the down stroke and a leather strap for the upstroke. I knonw there is a difference in helve and air hammers but the forces are very similar. Bradleys use this on hammers from 15 to 500 lbs. Is really pretty simple and the idea may be useful on the Kinyon style hammer.

[John Larson]

An advantage of the new Kinyon design, and also of the Phoenix design, is that the piston area for lifting the tup is not reduced by the area of the rod. I am reluctant to criticize the spring idea of Ron Kinyon if it doesn't kink where the cylinder rod attaches. I thought the picture of the one taken to ABANA Seattle showed such a problem.

I have never broken a cylinder rod. But hey stuff happens. It could easily happen. I have had an NFPA clevise break and from that point on I avoided cast iron clevises. Shop-made steel clevises have never failed me. I no longer use clevises per se. The two-axis top mount comes close, though. I have had one ball connector fail, but the cause will never be known. I can only do machining that minimizes stress risers. Power hammer try their best to rip themselves apart. Any looseness becomes worse over time. Should a connection start to flex away from vertical, it will bend-flex-crack-fail eventually. Vertical alignment of everything seems pretty important to me, even though helve hammers have been hugely successful through a very long span of time.

I just came off a week end of guys using my Octagon 50 for all it was capable of doing. I kept thinking how Jesse James and Grant Sarver have shown how their monster machines cog down big stock rather effortlessly. Highly stressed small hammers cannot possibly be as durable as big old hunkers that aren't pushed to their limits.

[youngdylan]

An advantage of the new Kinyon design, and also of the Phoenix design, is that the piston area for lifting the tup is not reduced by the area of the rod.

How do you go about dealing with this imbalance between up/down forces on the tup in your Ironkisses John. Do you use a regulator in the supply to the top of the cylinder. I built a KA75ish hammer with pulling instead of pushing cylinders and the improved balance really improves the control.

[Nakedanvil - Grant Sarver]

Wow, terrible gravity storm today, can't hardly get out of my chair, guess I'll just have to wait it out.

[John Larson]

I don't have to do anything to balance forces. On my blog I've discussed how I establish the lifting forces needed for a given tup weight. The push-down forces give hammering power, the more the merrier. With poorly sized cylinders the lifting piston area is simply inadequate.

The Mike Linn setup shown long ago and still archived by the Alabama Forge Council saves poorly designed hammers by essentailly reducing push-down psi. By running really high pressure on the lift-up side and moderating the pressure on the push-down side you can achieve extremely snappy rebound, but your hammer actually tends to be come weaker. Far better IMHO to put a big enough bore cylinder on the machine to begin with.

Generally, for a given tup weight, I think you will find that increasing cylinder bore (within reason) lowers operating pressure and (this is the big deal here) your compressor spends less time pumping air. The reduced pressure more than offsets the bigger piston's cfm demand. And this can lead you to consider using big cfm, low pressure compressors.

Many guys let budget consciousness dictate the technical design issue and so they end up with low-buck, low- performance. Solve the technical problems on paper and then figure out how to pay for it. Once a hammer is running right, you won't remember the dollars you might have saved here and there. I've been down that road and can safely say that I am pretty tight with the dollar. My entire spate of grief with the first build of the 50 was caused by trying to use a reject 5-port valve with random performance problems. Many hours of shop time were spent chasing a problem caused by a $115 valve. Being cheap is not smart, usually. I'm here to testify.

[Dillon Sculpture]

How do you go about dealing with this imbalance between up/down forces on the tup in your Ironkisses John. Do you use a regulator in the supply to the top of the cylinder. I built a KA75ish hammer with pulling instead of pushing cylinders and the improved balance really improves the control.

Cool hammer, I always have to spray paint the safety colors off the tools I get though.

[youngdylan]

Cool hammer, I always have to spray paint the safety colors off the tools I get though.

.... ah but this home brewed beastie has an unguarded tup (for now) and I don't won't to get clouted in the head by it on the upstroke as I lean in to look at the work. That colour is called "signalisation yellow" on the spray can. I guess it's probably one of the most noticable colours.