Fly press tooling, speed?

[AdrianH]

Just wondering about this, when using fly press tooling to punch a hole or slot etc, I assume there is a fair bit of travel speed with the punch.

Does it have to be quick, can it be slow but tonnage rather then quick with tonnage.

i.e can it be done hydraulic ram or using a long bar for leverage?

Adrian

 

[Kent]

Swing the arm round with intention and the flyers carries serious force
I was speaking to a lad as he chopped his finger clean off in a fly press recon it maybe had 15 degrees to bottom out- treat them with great respect
Remember it's energy through mass x velocity squared rather than just pure weight that you get with hydraulic rams
Seen some serious stuff worked cold in s flypress when a big guy gives the arm a hood fast spin

 

[Tinbasherdan]

Just wondering about this, when using fly press tooling to punch a hole or slot etc, I assume there isa a fair bit of travel speed with the punch.

Does it have to be quick, can it be slow but tonnage rather then quick with tonnage.

i.e can it be done hydraulic ram or using a long bar for leverage?

Adrian

Hydraulic punches aren't particularly fast mate, a big ram would work fine, even on a hand pump. Better on a small power pack tho

 

[Maker]

The faster you throw the weights the more momentum they will have, so the more force it can press with.

 

[500e]

http://www.ebay.co.uk/bhp/fly-press-tooling

 

[AdrianH]

Sorry obviously I have not been clear.

I know that with a fly press one can use the momentum of the balls and speed acting on the feed screw and that gives the tonnage to punch through, but as I sold my fly press on, can I use the same tooling with a hydraulic jack that just relies on pressure, will it still work?

I appreciate one can bend steel with applying pressure slowly, and that slowness, can allow one to get the correct bend, but can one still punch through cleanly?

Adrian

 

[pedrobedro]

We used to punch holes in 3mm plate with fly press at the boiler factory I worked in. You would need some serious leverage to do the same job with a bar pulling down on a tool

 

[Screwdriver]

A decent size flypress will deliver a good 5-6 tons at the head. I often find if I am punching say a 1" hole in a 1.2mm sheet, I need to bounce the press a couple of times. This relatively high speed "shock" does seem to penetrate better but that is probably because the speed is delivering more force.

I would expect a decent ram specced at 10 tons would be able to use the same tooling and do the same job. BUT! Your hydraulic ram will need to be fitted to a MASSIVE frame. Those flypresses aren't built to that size just for show and if your framework distorts at all, you'll probably end up shattering a fair few tools. Whatever framework you build will need to be capable of the maximum amount of force delivered by the ram. You will inevitably push the system to its limit at some stage and when all that force "lets go" you wouldn't want to be anywhere near it!

So yes, your tooling will work fine with a hydraulic system but just make sure the frame is robust enough to resist bending.

S.

 

[Kent]

Sorry obviously I have not been clear.

I know that with a fly press one can use the momentum of the balls and speed acting on the feed screw and that gives the tonnage to punch through, but as I sold my fly press on, can I use the same tooling with a hydraulic jack that just relies on pressure, will it still work?

I appreciate one can bend steel with applying pressure slowly, and that slowness, can allow one to get the correct bend, but can one still punch through cleanly?

Adrian

Depends on whatever doing but punching I think without speed your onto a bit of a looser unless it's very light work
Speed is a big multiplier just try pressing bullets into seel no mater the weight applied the bullet will squash yet traveling at 3000 fps the same bullet will cut through an rsj clean
Ok? Give it s go but don't push things or spend a lot of time on it if it doesn't work straight off

 

[Screwdriver]

Depends on whatever doing but punching I think without speed your onto a bit of a looser unless it's very light work
Speed is a big multiplier just try pressing bullets into seel no mater the weight applied the bullet will squash yet traveling at 3000 fps the same bullet will cut through an rsj clean
Ok? Give it s go but don't push things or spend a lot of time on it if it doesn't work straight off

No I think that's a very different effect you're talking about.

Certainly if you push the tool hard enough it will deform and shear exactly the same as a flypress. All I am saying is that a flypress, being a quarter of a ton of cast iron, is a super rigid frame to apply that force precisely. If you push with a hydraulic ram, any slight distortion or flex in your frame will give you very unpredictable results.

For example, you might wind up your frame like a spring and when it finally goes, it REALLY goes. A flypress is as stiff as a lump of iron so there is a negligible residual force being built up behind the tool head. This means a flypress is incredibly accurate and sensitive when you want to just ding something by the tiniest amount for example.

 

[AdrianH]

Well I am not after much, with regards to hole size, talking at the moment 4mm in 2 mm sheet. So tonnage typically in a fly press would be around 1 ton, so please do not worry I am not after a lot. I also have a rise and fall sort of table, it was meant for a fly press has two ground columns on it that the top slides up and down to keep it all set correctly, if I can use that I will. Using a bar lever for that sort of pressure is not that difficult, or even a small jack, it is just the speed of the ram that I am wondering about.

Adrian

 

[Screwdriver]

Then all you need to worry about is what happens at the moment the punch perforates the sheet. With a lever it will be difficult to stop it due to bending plus you're probably still hanging off the end! A hydraulic ram would lose all pressure instantly and assuming no spring in the structure, the tool would just stop.

The most difficult part in punching holes is getting the punch out of the hole. If the lever pushes it too far, it might reach a wider part of the bit and jam. It's well worth setting it up with a strong spring to retrieve the bit, valve spring would do.

S.

 

[Screwdriver]

Personally, I don't think speed is an issue, it's all about pressure.

What I don't know is how much effort you have to put into a typical jack to develop the power needed. In your example, probably about the same as lifting a vehicle I guess. But to get 5 or 6 tons, you might need a fairly substantial jack.

S.

 

[AdrianH]

Looking on ebay the majority of the smaller ones are 2 tonne then a few 4, 5 and 6 tonne then above for the heavy duty ones and typical prices start at under £10.

I have welding to do tomorrow to put the frame together. Then I will take it from there.

Adrian

 

[AdrianH]

OK, this is it so far, a large squarish Donut:

Inside dimensions are 500mm and 300mm, all from 100 x 4mm wall ERW box.

I used the 2 Tonne jack in both directions and left it there for a while on full pressure, then had a play.


3mm plate 135mm wide
.

Just need to figure that mod to a bottle jack and then come up with a way of fastening the jack and tooling together.

Just playing .

Adrian

 

[Wallace]

Just need to figure that mod to a bottle jack and then come up with a way of fastening the jack and tooling together.Adrian

I made a similar frame from heavy 4x2 U channel some years back and managed to bend that with a 10 ton ram. The bottle jack needs a tube in the oil pick-up hole on the base up into the reservoir so it will work upside down. If you want to play with air over hydraulic on the cheap I found these cheap on Ebay.

 

[Hitch]

A simple cam/lever opearated setup would bang a 4 through 2 pretty easily. Only just over a tonne required for that.

The metalcraft punch/shear would be worth looking at...says 6 through 3, which would be in the region of 2.5 tonnes.

 

[AdrianH]

I saw the mod to the bottle jack, also need to be able to insert the bar from the back of the normal arrangement otherwise one has to push up to apply pressure.

I will not be going to 10 tonne, possibly get a 5 Tonne bottle just so it is not labouring, but will continue for the time being with the 2 Tonne.

As I say the next thing is to figure out how to hold things so they do not fly out under pressure.

Adrian

 

[Kent]

No I think that's a very different effect you're talking about.

Certainly if you push the tool hard enough it will deform and shear exactly the same as a flypress. All I am saying is that a flypress, being a quarter of a ton of cast iron, is a super rigid frame to apply that force precisely. If you push with a hydraulic ram, any slight distortion or flex in your frame will give you very unpredictable results.

For example, you might wind up your frame like a spring and when it finally goes, it REALLY goes. A flypress is as stiff as a lump of iron so there is a negligible residual force being built up behind the tool head. This means a flypress is incredibly accurate and sensitive when you want to just ding something by the tiniest amount for example.

No I am talking about exactly what mean. Speed is a great multiplier
You need more force to overcome the advantages
The issue with punching holes slow with pressure is deformation sticking and burs

Will it work? Perhaps but looking at the frame I should have just drilled it in advance
If the frame already existed then an angle or lock drill could be employed if you haven't clearance for a std hand drill

 

[AdrianH]

When jack modified and now works up side down, used, ATF as the oil, will see if it makes a difference long term.

Tomorrow more work as only had 2 hours in the garage today.

Still playing.

Adrian