Sieg SX2.7 Quill Fine Feed

[Nigel (egi)Participant @nigelegi]

I have the Sieg SX2.7 from ArcEuro – what am I missing: when I release the captive drawbar it drives the quill downwards and doesn't release the MT3 taper?

If I tighten the quill so that I'm in fine feed it still drives the quill down and doesn't release the MT3

The only option I've found is to use the old fashioned method of releasing the drawbar a small amount and then using a mallet to shock the taper into releasing

Edited By JasonB on 11/09/2018 07:47:06

[JasonBModerator @jasonb]

Nigle, have a read of this post I wrote about the correct operation of the SX2.7 and X2.7 mills and it will tell you how to correctly lock the quill when changing tooling. Engaging fine feed risks damage to the feed gears.

For the R8 version Self release be improved by adding a small spacer to the top of the drawbar so that it will break the tapers grip after a couple of turns so there is still plenty of thread engagement, on some tooling it can release right at the end of the thread which may wear the thread or allow the tooling to drop. May not be needed for the MT3 version. Details of spacer

J

 

Edited By JasonB on 11/09/2018 07:49:58

[JasonBModerator @jasonb]

[Paul LousickParticipant @paullousick59116]

Nigel,

Most M3 tapers require a whack on the end of the draw with soft mallet (lead or copper) to release the tool unless it is equiped with a special drawbar which pushes the tool from the spindle. I used to have an SX3 and placed a wooden block under the spindle before hitting the drawbar to take any load away from the bearings. Then made a special wedge extractor to remove the tool. (published in MEW a couple of years ago). Locking the fine feed and hitting the drawbar could break the gear.

Paul

[Brian GParticipant @briang]

Nigel

We have an MT3 X2.7 and it releases easily using the self-ejecting drawbar, although it helps if the drawbar isn't overtightened. You need to release the quill lock (the cap screw on the left) and the fine feed to let the quill go right up to the top (otherwise there will be less thread engagement and the tool may fall out when you unscrew it), then lock the quill very tightly before unscrewing the drawbar.

Brian

[JasonBModerator @jasonb]

Brian, thanks for confirming that teh MT3 version will self eject without altering the drawbar length.

Paul the X2.7 and SX2.7 have a substantial metal cover over the top of the drawbar for it to push against when loosened which will self eject rather than the plastic cap of the X3 so no need for hitting or wedging.

[Paul LousickParticipant @paullousick59116]

Thanks Jason. A much needed improvement.

[Nigel (egi)Participant @nigelegi]

Thanks all, must admit that I ignored the lock/release label even though I kept wondering how to lock the quill

[Nigel (egi)Participant @nigelegi]

Just had a play and once locked it is easy to then release the taper using the captive bolt.

The only small issue is there is not much space between the on/off speed control box and the bracket that holds the sensor for the shield (sorry, had to remove the plastic shield as I find them more dangerous ) and so small movements of the allen key – but it does work – thanks to Jason for pointing this out.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Nigel (egi) on 14/09/2018 15:23:44:

The only small issue is there is not much space between the on/off speed control box and the bracket that holds the sensor for the shield (sorry, had to remove the plastic shield as I find them more dangerous ) and so small movements of the allen key – but it does work – thanks to Jason for pointing this out.

.

Might be time to invest in a suitably compact ratchet wrench ?

MichaelG.

[JasonBModerator @jasonb]

Or replace the cap head screw with a custom one with integral tommy bar or even a Bristol lever to match the axis locks. It only needs 90deg rotation at the most to go from locked to free moving.

Edited By JasonB on 14/09/2018 16:09:25

[Brian GParticipant @briang]

Posted by JasonB on 14/09/2018 16:08:10:

Or replace the cap head screw with a custom one with integral tommy bar or even a Bristol lever to match the axis locks. It only needs 90deg rotation at the most to go from locked to free moving.

Edited By JasonB on 14/09/2018 16:09:25

I fitted a lever to my son's machine to save having to keep finding the wrench (like a telephone, I tend to pick up with one hand, put down with the other, which means it is always moving around). That way the wrench can stay with the pin spanner to hold the spindle and I might have a chance to find both.

Little Machine Shop sell a knob for the quill lock which removes any restriction. To be honest I don't think I could tighten it enough to release the taper, but then again they also sell a spindle lock that completely disables the self-ejecting drawbar anyway. I guess Americans must like hammers.

Brian

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