Fly presses – weights and capacity

[Dave Jones 1Participant @davejones1]

I was wondering if anyone would be able to point me in the right direction. I have been looking at second hand fly presses. I am after something is able to bend (upto 90 degress) and punch holes in brass and mild steel up to 1/8" thick at the most. Whilst I have managed to work out that the presses come in sizes 1-6, I cant seem to find any sort of rough idea of what the different sizes weigh and what sort of size I would need to be able to do this.

[Dave Jones 1Participant @davejones1]

[Dave HalfordParticipant @davehalford22513]

The number refers to the tonnage delivered eg a 2 is a 2 ton press.

You need 2 tons to form a 1/8" rivet head. punching you can get from the hydraulic versions on ebay that run off a 10 ton ram they seem to go up to 2"dia for 1/8 steel.

[Nicholas FarrParticipant @nicholasfarr14254]

Hi Dave, as far as bending, it will also depend on the width you want to bend. The wider the bend, the more force will be needed. Brass that is soft or even half hard will bend easier than steel. My No. 4 flypress will bend a bit of 2.5mm thick by 150mm wide steel with ease and will probably do 3mm. Mine weighs about 160 Kg. A No. 5 will weigh in the region of 270 Kg and a No. 6 in the region of 320 Kg. Punching holes will also depend on the size of the hole.

Regards Nick.

Edited By Nicholas Farr on 02/10/2018 21:29:42

[Robert Atkinson 2Participant @robertatkinson2]

Unless you have a very good reason to want a flypress I suggest you consider buying or making a hydraulic press. The only advantage of a flypress is speed and compared to a simpe frame an open working area. The downside is they are heavy take up a lot of space and are dangerous. If you don't crush a finger you will at least bang your head on the handle. A frame made of U section structural mild steel and a hydraulic jack is all you need. Compact, powerful, lighter (and can be dissasembled to move o store) make the cross mean movable and you can fit taller items in.

Robert.

[Dave Jones 1Participant @davejones1]

Thanks for the advice. I will have a rethink and go for a hydraulic press instead.

[Clive FosterParticipant @clivefoster55965]

A home made hydraulic press using a hydraulic jack in a structural steel frame as suggested by Robert can work very well. I made one myself. Various designs to be found on the internet.

The major problem with this style of press is arranging accurate ram guidance. Normal practice is to suspend the jack on springs with a tubular pusher fixed underneath. The pusher runs in some sort of guide bearings carried in a suitable cross member beneath the jack. I practice the fit of the guide bearings has to be on the slack side to ensure things don't bind up. I made mine an engineering sliding fit which proved no end of trouble. Opening out by 40 thou / 1 mm (ish) on diameter sorted things but now you have to be very careful with set-up to avoid pushing on the skew. Best done as a two handed job as the jack pump handle is inconveniently positioned for operation and spring mounting promotes wobbles. Under the circumstances its hard to hold the bit being pressed on just so with one hand.

One attractive version seen on the internet used a pair of redundant motorcycle fork legs as guides for the jack carrier. Which looks as if it would work well. A couple of years or so ago an article in either MEW or ME explained how to run the common import bottle jack inverted. Presumably this would allow you to use the bottle jack directly as the ram with stability comparable to more "proper" systems with hydraulic cylinders.

Costs need watching if you don't have a well stocked "useful bits box". 10 ton rams, cylinders and Porta-Power sets can be found for £100 or less if you wait. Likely to give a much better behaved result than the simple bottle jack on springs for not silly more money. When I made mine the cost differential in favour of the bottle jack was much greater.

If you go the bottle jack on springs route, springs from a broken / discarded trampoline should work well.

For smaller jobs and short strokes the generic 12 ton screw operated rams sold as spare parts for various pullers are attractive. I made a suitable carrier to use one in a device for removing the swivel ball joints from my Range Rover P38. Looked like the official tool but under 1/10th price. Used rods from my generic Chinese milling hold down kit to connect the ram carrier to the hollow extraction end. I really should revise things and write it up for MEW as a small, versatile, hydraulic press project.

Clive.

[HopperParticipant @hopper]

One way around the problem of the wobbly top moving ram guide is to make your dies with their own built in guide pins and bushings, or a pair of top and bottom plates with guide pins and bushings that you can then bolt your various bending and punching dies into. If you do a google image search for "die bolster" you will see the principle illustrated better than I can describe it.

[Barnabas TaylorParticipant @barnabastaylor89961]

I bought my flypress sort of by accident because it was close by when I was looking on eBay and it seemed like fate. It is monstrously heavy and was a bit of a nightmare to set up on a stand (no money so everything had to be home-made and home lifted) and it is too big for my garage but I love it to bits! It is a fantastic tool and has lead to many projects being possible now. One thing that hasn't been mentioned, is that a flypress is infinitely more cool than a hydraulic press and any workshop with one in definitely means business! I repainted mine and I went for what was supposed to be battleship grey (according to the website) but it turned out to be quite a bright turquoise. I didn't want the fuss of sending it back for a refund so now I have the brightest flypress I have ever seen!

[Colin HeseltineParticipant @colinheseltine48622]

I run two fly-presses in my workshop both fitted with different tooling. Both are fitted with Hunton Bolsters, one is normally set up to punch 5mm diameter holes (either in 1.5mm or 3mm aluminium, the second is set up with radius punch and die for usually cutting 3/4" radius on 1.5mm or 3mm aluminium.

I also have a 10 ton hydraulic press I made up over 40 years ago. This is made up of heavy 'U' channel welded up into a frame. It uses a 10 ton Portapower hydraulic ram. This has removed an refitted lots of bearings, e.g. axle bearings on half-shafts.

I have used the hydraulic press to bend heavy stuff but normally use a 24" folder.

The fly-presses are heavy and need two people to lift onto bench and also need well fixing down. Would not be without them, but I must admit 800+ operations in a day on the flypress does not do the shoulder any favours. Luckily this does not happen very often, once or twice a year.

Colin

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