Presses - open for a debate

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bigHUN

bigHUN

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Jan 16, 2020
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I am reading these post about swagging presses for long time maybe years, so far I had not much interest to invest into that direction. Instead of making my own amo whatever design that would be - that amount of time I was investing into my shooting, training and practising.
It it not mine to say or proof that some new slugs design will (or not) improve the scores, but the pellets I am watching everyone makes are all the same cloning of existing shapes and parameters.

Recently I started shooting f-class longer ranges, a friend was reloading for me. At some point I decided with mutual interest to do reloading DIY -and invested into equipment.

And here comes my Question:
- Why reloading presses and in our OP the slugs/pellets presses - all rocker style? (came to my mind watching the europeanairguns new press and saw the guy was kind of wrestling with it - this comes if you don't eat a good breakfast first :) )
Why not rack and pinion or eventually shaft driven?
This question comes from a mechanical engineering point of view ;)
 
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bigHUN said:
I am reading these post about swagging presses for long time maybe years, so far I had not much interest to invest into that direction. Instead of making my own amo whatever design that would be - that amount of time I was investing into my shooting, training and practising.
It it not mine to say or proof that some new slugs design will (or not) improve the scores, but the pellets I am watching everyone makes are all the same cloning of existing shapes and parameters.

Recently I started shooting f-class longer ranges, a friend was reloading for me. At some point I decided with mutual interest to do reloading DIY -and invested into equipment.

And here comes my Question:
- Why reloading presses and in our OP the slugs/pellets presses - all rocker style? (came to my mind watching the europeanairguns new press and saw the guy was kind of wrestling with it - this comes if you don't eat a good breakfast first :) )
Why not rack and pinion or eventually shaft driven?
This question comes from a mechanical engineering point of view ;)
Click to expand...
i wondered that exact same thing too.
 
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Reloading presses for sizing brass generate tons of force using a four-bar linkage that cams over slightly and just locks in the up position.

A friend of mine is pressing slugs using a cam over style press and he really prefers it. He basically watches the lead squirt until it stops flowing. This takes a few seconds and having the cam over means consistent press force without beating yourself up.

I’m sure that bullet swaging presses would also work but they’re probably overkill for slug swaging.

Arbor style bullet seating presses don’t generate much force. They’d never handle anything with slugs.
 
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dgeesaman said:
...Arbor style bullet seating presses don’t generate much force. They’d never handle anything with slugs.
Click to expand...
I don't know, this why I was asking.
I am using a Wilson seating die, I have an older rocker style press right beside my HF "micro mill" with a pinion. I can feel much easier pressing the die with rack and pinion vs the rocker. For this reason I didn't invest $ for K+M or 21st Centuri bench presses, but I bought a press force pad from ali to monitor a consistency.
 
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I have a K&M arbor press and while it’s sturdy enough for seating bullets with heavy neck tension, it’s barely enough force to swage 177 pellets. And it would probably wear out the gearing quickly.

I also have a 1 ton standard type arbor press I use for swaging pellets and it’s pretty good for that with a longer handle. For forming slugs it might not be enough and even if it was it would take serious physical effort to hold the force for more than a couple seconds.

I haven’t done any swaging with my Rockchucker reloading press because it doesn’t fit in that press.
 
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dgeesaman said:
I have a K&M arbor press and while it’s sturdy enough for seating bullets with heavy neck tension, it’s barely enough force to swage 177 pellets. And it would probably wear out the gearing quickly.

I also have a 1 ton standard type arbor press I use for swaging pellets and it’s pretty good for that with a longer handle. For forming slugs it might not be enough and even if it was it would take serious physical effort to hold the force for more than a couple seconds.

I haven’t done any swaging with my Rockchucker reloading press because it doesn’t fit in that press.
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@dgeesaman If I’m not mistaken the 1 ton Arbor presses are used in conjunction with the older styled GMI slug dies. @Engg.Ken can elaborate here better than I can. I’m just going on a vague memory of some YouTube videos I’ve seen.
 
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Ezana4CE said:
@dgeesaman If I’m not mistaken the 1 ton Arbor presses are used in conjunction with the older styled GMI slug dies. @Engg.Ken can elaborate here better than I can. I’m just going on a vague memory of some YouTube videos I’ve seen.
Click to expand...
I've used the 1 ton press with the GMI dies. 2 ton would be better I'm guessing, but it works.
 
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Typical swage presses (and reloading) change leverage ratio through the stroke. It’s higher geared mid stroke and as it nears the end of its stroke becomes extremely low geared. This small movement at the end is where the real work takes place. The rest of the movement is to allow us to place/retrieve our core/slug. Win/win so to speak.

A typical rack/pinion type press is the same gear ratio throughout it’s stroke. To be low enough geared for the hard part, it would be unreasonably slow for the rest of the stroke.

Dave
 
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Thanks for the mention @Ezana4CE and @Corvid_hunter . Here is my take on the subject @bigHUN .

We need huge amounts of force at the end of the stroke, the toggle mechanism or the rocker mechanism has a geometric mechanical advantage where the end position thats 180 degrees lend an infinite surge of force, I think Tan 90 is infinity or undefined.

Whereas rack and pinion basically have a plateau zone,

Where you find a plateau zone, or the absolute limits, your force input needs to increase exponentially to overcome the effect. ( Thats why we recommend longer lever on the arbor press)

The European press suffers from engineering constraints, its a good concept but miles to go.

When we were designing the GMI Freedom 2 press, we considered the fact that the infinite magnitude of force needs beefed up point contacts such as bearings and pins. But it needed a range of motion for the mechanical advantage to be present.

So, we did try rack and pinion, and other mechanisms, but nothing beats the mechanical advantage and stroke advantage of a rocker mechanism or a toggle mechanism.

Hydraulics are the next big things, we are working on it, There is huge potential but the obvious challenge of weight, hoses and flexible joints are something we are figuring out.

How we calculate the force, That's our secret sauce !
 
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Engg.Ken said:
... need huge amounts of force at the end of the stroke, the toggle mechanism or the rocker mechanism ...
Click to expand...

I've been in engineering long enough (as NPD = new product development engineer) also I know first hand pretty much all the fabrications involved...
The niche prices I have seen around for these presses really made me brainstorm for DIY ;)
 
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Ezana4CE said:
@Corvid_hunter Thanks for the confirmation. Which caliber did you use the 1 ton in making your slugs? Why do you say that a 2 ton would be better for you?
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I use the arm off my Lyman press to get more leverage on the 1 ton press and give it a couple of additional taps with the ram after the initial stroke. I probably don't have to do that part but it's habit now. It does work perfectly fine.
 
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The dies in the press?

No, I sold my dies in 2000, no matter what I did, the accuracy was never on par with commercial bullets/slugs. I found that casting slugs then pellets yielded the same group sizes for me and it was infinitely faster to do so I switched to casting instead.

I still buy a lot of pellets and slugs, there is a magic sauce they use when swaging pellets commercially that just gives better grouping.
 
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Engg.Ken​

Have you thought about using an electric motor to attain the force necessary?
Not saying that it will work, but in shotshell reloading, MEC has an electric motor style press that works nicely. It's small and flat, something that is actually mounted underneath the shotshell machine to provide the necessary force on the operating mechanism.
MANY that once had hydraulic have switched to this electric version due to noise and leaks from hydraulics.
Just a thought.

mike
 
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Revoman said:

Engg.Ken​

Have you thought about using an electric motor to attain the force necessary?
Not saying that it will work, but in shotshell reloading, MEC has an electric motor style press that works nicely. It's small and flat, something that is actually mounted underneath the shotshell machine to provide the necessary force on the operating mechanism.
MANY that once had hydraulic have switched to this electric version due to noise and leaks from hydraulics.
Just a thought.

mike
Click to expand...

@Revoman I am working on a geared stepper motor concept. There is merit in electric / electro mechanical aspect of press operation, We do get the necessary force output . We are working on improving the service life of the equipment especially the wear and tear of bearing parts, It should not be long when you will be able to have a Desktop small cal Swage machine from GMI :giggle:
 
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Corvid_hunter said:
I've used the 1 ton press with the GMI dies. 2 ton would be better I'm guessing, but it works.
Click to expand...

I think if you're a big guy then the 1 ton would be fine.

I'm not a big guy and found the 2 ton worked fantastic in comparison. Though one needs to be careful to make sure everything is aligned well so as to not damage the tip former that gets pushed into the die actual.
 
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