Member postings for Chris Heapy

My rear toolpost has many, many uses other than for mounting a parting tool - which I do for convenience as much as for performance. As stated above, a complete answer covering all issues you may encounter while parting in the lathe would cover many pages and the beginner should search out the articles already posted. However, the Eclipse tool shown (like mine) is not the best tool for the job. It is cheap - albeit the replacement blades are costly - but an inserted-tip type tool with a good profiled carbide tip is far superior in both performance and rigidity. The shaped tip is able to curl and clear swarf more efficiently than the large blade. If the Eclipse blade is not set dead square to the work (in addition to the tip being at exactly the right height) then shortly after starting to cut one side or the other will gaul on the inside of the cut, it will then jam up pretty quickly.

I use a couple of those in a rear toolpost, I find I have to grind the top of the blade flat to obtain better chip clearance (which is poor with this type of tool) and plenty of cutting fluid. The 3/32" blade is fairly sturdy and will part up to 2" dia or so, I have the 1/16" blade tool also which is good for small diameter work and saves on waste because of the narrow cut. Both need the cutting edge re-shaping to be optimal (a bit more top rake, and I make mine hollow ground). I wouldn't like to operate either in the normal position on the topslide because of the poor chip clearance, I used to get frequent jams also like this, in my experience back toolpost only for these.

I'm with John on that, and I would add it is better to disengage the leadscrew and push the slide by hand to feel the resistance. Hopefully the steel gib strip will wear faster than the cast iron slide so replacing the strips with new ones may offer some improvement, otherwise it will be necessary to get the parts re-ground. If you're in the habit of using a slide locking screw (which presses against the gib strip) then this is often a source of localised and uneven wear.

I use a recycled file as a scraper - not something I use very often I have to admit.

Well, these things are free (bar postage cost - and you'd be surprised how heavy they are) to a good home if anyone wants/can use them.

This box of large carbide cutting tips was given to me donkey's years ago, and they've sat in their box ever since because I can't think of a use for them. They are 3/4" square and 1/4" thick - clearly heavy industrial tooling of some sort. Any suggestions for a use?

Hmm. Don't know really. I've been at it nearly 2 weeks now but I haven't been in the workshop every day. Maybe 20 hours so far.

.oOo.

I made part of the adjustable limit stop, this fits on the end of the block and allows you to set where the cut starts and ends. Several ways of doing this occured to me and I fancied a circular T-slot (so it's a C-slot?). Anyway, I was going to use a t-slot cutter on a circular blank clamped to the rotating table but experience cutting the stainless steel (formerly residing in the scrap bin) in the lathe suggested this would present a problem. The metal is very tough to cut. So change of plan - I made the thing in two parts held together by screws.

I need to make the captive nuts and the two stop pins yet, but when assembled the pins can be positioned at any point around the slot.

LOL, everything I do is a bodge one way or another Take this fine example today of how to slice the end off a workpiece that was too short. No chance of parting it in the lathe - apart from bieng too thin to hold securely this stuff is stainless steel and not too friendly with parting tools.

Nice work Dave, well done!

Spent the last 2 days trying to fix my computer. Looked like a HD failed but in fact appears to be the SATA controler that broke. In between watching restore processes on the computer I managed to make a little more progress on the ball turning tools.

Milled a couple of blocks to fit my Dickson-type quick change toolpost

These were then drilled and reamed 1/2" to accpet the pivot shaft.

The ball turning head fits in these blocks, something like this:

Just drill 7/64" then poke a 1/8" reamer through until you see its cutting edges appear on the far side. Put a faint chamfer on the pin and press it in. Job done. Sometimes we over-think these things...

A rather miserable evening weather-wise, so still tucked up in the workshop. Made a tool holder - which was an interesting machining exercise. I know - it didn't have to be this shape to be purely functional, but I wanted it that shape because it was more fun to make. Locks up firmly with just one screw.

Ah. Anticipation... of making a b***s up with one and still having the other to work with Should both survive the entire process I will sell it or dispose of it some other way. Half the work is in setting up the machines for the cuts so it's not much more work to make two than it is for one - and far easier than starting again from scratch.

Ball-turning tool(s) still progessing according to plan. Oh, hang on, there wasn't a plan... OK, well just still progressing then. Better to make it first and then construct the plan afterwards anyway.

Made the leadscrews:

Then cut a T-slot in the slide for the tool holder:

There are many steam rallys where this happens so we are not short of this type of venue, The ME show is not a car boot event.

I would bolt it to an angle plate rather than use the vice.

Cleaned my motorbikes then took the Scrambler out for a run. I swear I won't have another bike with spoked wheels because they are a pain to keep clean... If the weather is fine I will ride up to Harrogate on one of them for a look around the show, that will stop me buying anything big . Spent a couple of hours in the workshop earlier this evening.

How about drilling a round hole and filing it square? am I missing something? Very useful tool the simple file

My feeling is that the degree of 'tipping' of the moving jaw is dependent not only on the clamp pressure used but also the shape of the workpiece and its position between the jaws (i.e., sitting at the bottom of the jaws, near the top, etc..). Simply shimming the top of the rear jaw is not going to resolve the issue for all situations.

It is also notable that when tightening this vice - unlike a standard vice where it is very obvious when the jaws are closed and resistance to turning the handle further increases rapidly - in this vice it is an uncertain feeling and you can seemingly continue tightening it by degrees with no feeling that it is secure. What is happening of course is that as you are applying more torque at the handle the jaw is just tipping more and more. This is worst when a thin piece is held near the top of the jaws, a situation that is not advisable at all using this vice.

If this device received a 'good' write-up then the reviewer must not have actually taken it out the box and tested it.

The only solution for this vice (as I see it) would be to provide more support for the moving jaw to prevent it tipping in the first place, rather than accept it and (try to) compensate for it. Imagine a pair of buttresses, triangular shaped pieces, bolted to the rear of the jaw with bolts angled in such a way that they force the buttressing pieces downward onto the slideway. I think you get the idea without a sketch.

Edited By Chris Heapy on 06/05/2013 19:01:05

Continuing with my pair of ball turning attachments, making it up as I go along

Made the female 'nut' thread from drawn PB rod, not my favourite material, but it will wear well and it would be replaceable (can't imagine it ever needing to be though).

Thanks, got the PDF now... I couldn't find it with a search

The vice is supplied with two handles - one with a short throw and one with a long throw for better leverage. The short one is necessary because the long one cannot be rotated fully without hitting something.

I'm considering a cunning plan but it would mean altering the vice, an irreversible machining operation so I might drop Warco a line first to explain my position. As Neil noted - it wasn't a cheap vice.