basher

high speed cutlers power hammer project.

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 Okay, so forget a tire, use a rubber wheel with a taper (truncated cone) of largish dia and the powered one an appropriately smaller cone. 

 

A potter friend had a cone drive/clutch/speed control on her wheel that would vaguely fit your description.

Oh yeah, progress pics are much appreciated, that way we can just copy yours instead of having to figure it out our selves. <grin>

 

Frosty The Lucky.

 Bill Gichner told me to "always buy the first one" and then modify design your own if you must! Along the lines "of a wise man learns by his mistakes...a lucky man learns by the mistakes of others"

 

Be lucky!.... Ah I see you already are!

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What do you consider a "small" foot print?  My 16 lb Depew is 14 wide 26 long 42 tall. it runs a 500bpm and makes metal flow.  For smaller I haver a 15lb electric jack hammer.  Make a mount and it would fit in a 7 inch circle.

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if you'll use a VFD, you won't have to over-complicate it mechanically, maybe something like engage/disengage "clutch" will suffice.

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Hi All

I found this build a while ago. Not to bad of a hammer to get a few ideas from. I know you don't like the tire hammer but his one has a round tup like the hammer Murry is using in his vid's.  You can do your own design and scale it to your needs and drive type. Check it out.

http://www.katanabuilders.com/katanablog/2058-2/

HH

CH

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Idk if you remember the clip of my old hydraulic motor hammer.I havnt taken any vids of the new one. I've thought about a tire hammer arrangement, with the same method. Say you lose the tire and motor, have the concentric on a hydraulic motor, treadle to the flow control valve. To size the motor, just figure your system gpm and size a motor for the rpm you want to hit at full out.

The new hammer has that control, one hits nice and hard, with the small hyd cyl under the spring pivot changes the hammer strike, I can adjust it up and down, withing a 1/4" of where I want, with the spring fwappage accounted for, light taps, or roundhouse swings. The presses are what made the footprint of a 6 foot long machine work for me.

old hammer vid, before I got the dies done right

http://s719.photobucket.com/albums/ww194/LogDork/?action=view&current=hammering1.mp4

new hammer

 

11-22-1-2.jpg

 

11-22-2-2.jpg

 

PS, in the video, I was just demoing on cold stock, It did a good job with improved upper die and hot iron. It was abbout a 25 lb head, the new hammer head weighs about 80 with the die. Idk if the 65 lb spring pack adds as part of the tup.

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A helve hammer certainly has its merits as far as simplicity is concerned as well as having a wide elliptical path of travel for the helve which creates a nearer vertical path for the guided ram.

A half helve is a possibility i guess (with the pitman on the same slide of the pivot as the ram).Helves are completly understandable (the engineering being within my "smiths" level of grasp.

 

 I want to go down either the inverter route or hydraulic route rather than making up a clutch interface. From my limited experience of seeing an inverter powered hammer the slow speed control was second to none. If I was to be doing some kind of clutch i would have to go down the steel on steel cone clutch route and I am not a good enough machinist (yet) to do that accurately.

 

 I have owned 3 hammers with cone clutches and it is a great way of variably transferring power...however in a high inertia system you tend to get a hard first hit as the initial inertia is overcome and the system suddenly has too much power. this is fine on thick metal on sub 4mm stock an extra deep hit is a knife trasher.

 

I have gathered in my pile of bits...

 

65mm diameter oiled nylon bearing surface 500 mm long (to be cut in half and give me 2 x 250mm bearings or 4 x 110 mm bearings to be used as separated pairs.

70 mm ram material to be lathed down.

vfd controlers and an assortment of motors from 2 to 10 hp also a potentiometer foot control.

hydraulic motors and a 7 or 10 hp power pack .

I have the main pulley bearing from a lift! which has a large pulley between 2 bearings and sticking out of the end is substantial plate with holes centred at about the same rad as my goliath this will be the hart of the hammer. I have been sitting on this for near a decade .

 quite a few solid lumps for anvils and tool steel of assorted grades for dies ( H 13 w2 1045).

 

I dont want to re invent the wheel but do have a slightly different idea for the tup/ spring configuration that will bring all the leaf spring /coil spring gubbins within the tup.

 I drew it out last night and will re draw today an post in a readable form.

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I had considered that.  and that is possibly the best looking tire hammer I have seen so far.

 it seems a great way to reduce the gubbins and also to make the weight of the springs part of the final momentum of the tup thanks for posting.

 here is my main bearing perfect for a hammer.

8262988157_49b55019cc_b.jpg

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When you say inverter controlled hammer, do you mean treadle direct to a VFD controller?  My buddy and I built two of these press/hammer units, I'm off the grid here and use a diesel for my power source, I tend to run it at half throttle, sometimes raising or lowering the RPM/flow rate for what I'm doing (will be doing, spent most of last winter working on this project). He set up on a 15hp 3-phase, and those presses really go fast. I should check the hammer speed with a laser tach I have, it seems pretty fast too, faster than I'm comfortable with. A VFD control on the motor would give another level of control for sure. But then for you a VFD controlled motor running a hydraulic pump, and hydraulic from there may be getting over complicated for what you're doing.

Do you have a video of the inverter controlled hammer? 

Here's a couple shots of the sister hammer to mine.

 

3-9-6.jpg

 

3-9-7.jpg

 

3-9-5.jpg

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Owen too bad you are against a helve, I think that would be perfect in this case. Are you worried about the blade bowing from being worked by a helve with a varying angle between the dies?

 

The japanese hammers use top and bottom dies that are both crowned just like a hand hammer face.

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the way i see it there are 3 choices when it comes to controlling the speed of hammer blows on a mechanical hammer.

 one is a clutch and there are many different versions of these.

 one would be to use a hydraulic motor and have the foot pedal connected to a valve.

 the other is to have a 3 phaze electric motor with a VFD and a potentiometer foot controle. and run the hammer speed direct from the motor.

 I have seen one of these working really well and will try it a s a first stop. I have vfds and a foot potentiometer.

 

Sam the reason I am steering away from a helve is the depth of the hammer but mainly the fact that i already have that bearing block and am fimiliar with mechanical hammers of the LG and goliath type.

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Maybe before commiting yourself to either, set up both, attached to the bearing block and bolted down, and see which method gives the control you like the best. I tend to think a hydraulic motor will start and stop on a dime better than an electric motor, I can go from full speed to stopping the head exactly where I want by taking my foot off the treadle and shutting the valve off there.

Part of the trick is to have the flow control valve as close to the motor as possible, I wouldnt put the valve at the treadle with long hoses, I'd put it close to the motor with treadle linkage to the valve lever.

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one potential problem with a high inertia system with a hydraulic motor in it is over pressurising the motor when you stop the motor dead and the system inertia is trying to move fluid .

 do you have the valve set with both motor ports shut or with a closed loop to the motor to allow for over rotation?

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Might be of interest that the hammer runs at around 500 psi or less. My system is more designed for higher flow, less psi. I run a 30" bandsaw (old parks resaw) off it as well with a hydraulic motor, and it hits maybe 800 psi pushing 10" of oak through, cuts smaller wood at under 500psi. My lathe or belt sander rarely go past 800 psi either and I have no complaint about the torque on those. I do slow down the bandsaw gradual to shut down, with a flow valve, it has big cast wheels to slow down, but rarely have had anything chucked up in the lathe not to just stop it rapidly turning the flow valve to off.

I have been living with  hydro-electric power for 20 years (25 gpm at 140 psi), line hammer is definitely an issue I know about with that. In the context of heavy duty hydraulic motors, and oversizing for flow, the problem is non-existant. All my lines are min 1/2" hose, and oversize steel tube for the shop plumbing.

Idk how well a power pack will do, considering that most were made for presses, and are designed for higher pressure and lower flow. I'm running around 10 gpm, and use a 6 cu in motor for the hammer, a 2.5 cu in on the bandsaw. 

I think as opposed to an electric motor, in this context the motor wear is less in a hydraulic motorin that that the hydraulic motor gears are in a cushion of oil, you're electric motor bearings, and motot parts would be getting a lot more abuse in sudden start-stop use. Just my .02, could be totally wrong.

Nothing fancy for the connections, just plumb the CF port on the control valve to the hammer motor in, and out to return. if you want to run it the other way just reverse ports on the motor.

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The way to control shock loading in a hydraulic system is with an accumulator. This is a compressed air charged tank in the hydraulic line to suck up over pressures. It'll also keep a set amount of pressure in the lines but doesn't have effect until the valves are open so doesn't make things dangerous. It will however make for a near instantaneous response seeing as it's got to be close to the motor.

 

On the other hand I don't much like having a hydraullicly driven mechanical hammer. It's just one more step for entropy and Murphy to have at you. Heck, if you're going to go hydraulics make a fluid drive hammer like a Massey, Beche, etc. The control valving is easy enough, all you really need is large lines in and out.

 

Frosty The Lucky.

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dang sam, Chuck Norris would stuggle to 90 deg flip the billet between blows on that one!

I know right, INCREDIBLE BPM. I would love to know more about that machine whatever it is.

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I know right, INCREDIBLE BPM. I would love to know more about that machine whatever it is.

Sam we've had a thread on that machine before. It is antique but still in use in several factories.  It is spring retracted with a high speed cam drive.  It has several stations that are each adjustable to different depths. 

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