Which Type of Hyraulic Press?

[Brian HParticipant @brianh50089]

I am thinking of buying a 6 ton press to use with broaches to produce small keyways.

I notice that the cheaper ones use what looks like an ordinary jack, suspended on springs and with the operating handle conected to the 'jack'.

It worries me that operating this type could cause the ram to wobble and upset the broaching.

There is another type with a remote cylinder to which the handle is attached that would not cause this problem.

Has anyone any experience, or comments about using a press to produce broached keyways and am I worrying unnecessarily about the types with 2 springs?

Brian

[Brian HParticipant @brianh50089]

[DaveyRParticipant @daveyr]

As far as I understand it, most manual broaching is carried out using a standard 'Broaching Press', which usually takes the form of a toothed arbor and gear, driven by a hand-operated wheel. I feel sure that an hydraulic press would achieve similar results, though, like you, I would be concerned about the potential for misaligned pressure being applied by the 'jack' style of press,

[JasonBModerator @jasonb]

I think you will find the springs are just there to close the "jack" and that the ram is rigidly fixed to the top of the frame.

The ones with separate cylinder have a built in spring to return the ram, I have used this type to do broaching without a problem.

[John RuddParticipant @johnrudd16576]

I have a 6 ton model with the bottle jack/spring arrangement to which you refer….

Although not specifically used for broaching, I've had no issue using it for removing/installing bearings on shafts/housings and the like…

[Antony PowellParticipant @antonypowell28169]

The main issue with the jack operated type press is the bulk of the jack body getting in the way when setting up, The specific cylinder type is far smaller and thus is easier to see past, otherwise stability is simply down to the design / make…

[John ReeseParticipant @johnreese12848]

The presses using a bottle jack have a lot of clearance between he crosshead and the columns. I suggest adding shims to reduce the clearance and minimize the likelihood of lateral movement.

[Clive FosterParticipant @clivefoster55965]

My version of the bottle jack type has a bolted in crosspiece with a nicely fitted bearing sleeve about 3" long to guide the pusher. Jack is essentially free floating on its return springs.

Pusher is 2" diameter tube with an internal thread to take appropriate end-caps. End caps get made as required so over time I'll have a selection.

Clive.

[IanHParticipant @ianh]

I have a Sealey 30T press based around a conventional looking jack mounted upside down. I bought this, used, some years ago and it has done good service. The problem with this press, and it may be a problem for all presses of this type, is that the jack has a coarse square threaded element allowing you to adjust the reach of the ram when setting up, and this is very imprecise. When I am pressing anything requiring any precision, I use a bolster to keep things aligned.

I don’t think I would attempt to broach anything with this press unless I had something else involved to keep everything lined up. The presses that feature a conventional looking hydraulic cylinder do not have this issue as far as I am aware.

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