Boring tool trouble

Hi,

im having a bit of bother trying to use a boring tool.

as you can see in the pics I can’t progress the tool any further on the cross slide, this is as far as it will go.

any ideas, what am I doing wrong here.

thanks

chris m….

Try rotating the top slide so the handle is nearer to you and wind it right in. Adjust the toolpost so that it is still at right angles and that should put your tool a bit closer to the lathe axis.

Difficult to say for sure but it looks as though the tool is as close to the back of the slot in the toolpost -- you can probably move it outward towards the machine centre thus putting the cutting edge closer to the machine centre.

there must be more to it than that as all my machines will send the tool post past the centre line

Plus one, there has to be something fundamentally amiss here. A picture taken from futher back would help, so we can see the whole picture, so to speak!

Just checked on my lathe (Harrison M300); when the cross slide nut is about to become disengaged the axis of the lathe spindle is roughly aligned with the centre of the 4-way toolpost. So a tool as shown would be well past the work centre.

Andrew

+1.. ..an ML7 ought to take the toolpost stud out to the centreline of the headstock spindle..?

I’ve tried it every other way, but it will not move past where you see it in the pictures, maybe it’s faulty somewhere.

I’ve only just come across this because it’s the first time I was going to use the boring tool, seems strange to me.

chris m…..

Mine finally 'grounds-out' as the collar on the feedscrew hits the face of the nut, I think.. ..I'll go check..

Edited By DiogenesII on 24/07/2022 16:30:16

Indeed it does.

A quick checklist;

..there's nothing fitted under the nose of the cross-slide to act as a 'stop'?

..there is nothing attached to or protruding from any of the cross-slide T slots to act as a 'stop'

..you can still see some feedscrew threads under the slide at 'your' end?

..have you got the tailstock pushed right back out of the way at the end of the bed?

Edited By DiogenesII on 24/07/2022 16:30:57

Just a thought.

Does the cross-slide movement hit a sudden stop or does it get progressively tighter until no further movement is possible? If the latter then the gib-strip needs to be adjusted.If the former, then look for some mechanical contact somewhere.

Hi,

it doesn’t come too a full stop, but does indeed get harder to turn the further you go.

how do I go about adjusting the gib strips, if this is the cause.

thanks for your help

chris m…..

Also there is a bit of play in the crosslide, backwards and forwards.

chris m…

That's backlash of the cross slide lead screw. My Emco Compact 8 bench lathe exhibits the same thing. The movement is about 0.1 mm, has never caused any problems. I would suggest to loosen the gibs completely and see if the limit of cross slide movement is still there. May be something is jamming the cross slide lead screw at the point where the cross slide cannot be moved further.

The gib-strip is adjusted by means of the small screws along the RHS of the cross slide. IIRC, they have lock-nuts.

With your symptoms, the screws nearest the front of the lathe might need slackening of very slightlyf. Adjustment needs care, but the internet should provide advice.

Don't worry about the end play at ths stage.

Have you loosened the tool post on the cross slide and slid it along the tee slot towards the chuck. For a tool this small some tool post overhang towards the chuck should not matter as long as the tee nut is fully inside the slot.

Another thing to consider is the use extended packing above and below the tool to allow it to stick further out of the tool post. Are you clamping with three screws? You will not need three clamp screws on this tool, two will be enough.

Martin C

Another possible reason for short crosslide travel as described by OP 17:06:19 is misalignment between feedscrew and its nut. I got heavy handed with my S7 on one occasion and bent the bracket downwards. Very stiff until I bent it upwards.

So I would disconnect the feedscrew bracket from the crosslide to check the latter's freedom of movement. Depending on the result of this test move on to check feedscrew / bracket alignment.

My suggestion to find where the problem lies would be to run the cross slide well out to the front of the lathe then remove the two screws either side of the bracket that holds the feed screw to the cross slide . You should then be able to manually move the cross slide back and forth, right off the saddle to the back if you go far enough. If you can't and it becomes stiff and won't move back then as suggested above the gibs need adjusting. If it moves freely back, then with the cross slide well back and holding the feedscrew bracket in one hand run the feedscrew in till the stop on the screw hits the saddle. If it goes all the way in with no binding then push the cross slide towards the front to meet the feedscrew bracket and reinstall the two screws. That should align the feedscrew with the cross slide and allow for full movement in and out of the of the cross slide. Doing this should tell where problem exists.

John