Thread: Regrinds R Us

Geeze, must have planted a seed of doubt a little while back, seeing this is something related to toolroom lathes going by the notification!

Won't be anytime soon, I think a mate is going to have his Colchester done via the $800 grinder, he mentioned his concern was the depth of the hardening yesterday too.

If you go from what's said on PM....and we all know how reliable the internet is....seems to be equivalent to nitriding depth to several millimetres depending on who you believe, - maybe induction v flame hardening causing the diverse answers. Interested to know what the Italians used.

How is everyone's 60* section of the vee by the way?

Originally Posted by Graziano

You can also see how the saddle doesn't contact the front way surfaces properly either, due to wear on the rear ways the saddle rise lower at the rear than it should.

Interesting. Good pic btw. Are you sure however that the gap isn't just at the ends of the saddle? If the rear way way lower for some reason I would expect the saddle to wear to match the same (now incorrect) angle. How much lower is the back? That looks like quite a gap, and I would have thought that over the width of a lathe bed, to close that gap the rear would have to come up millimeters

Pete

Originally Posted by Pete F

Interesting. Good pic btw. Are you sure however that the gap isn't just at the ends of the saddle? If the rear way way lower for some reason I would expect the saddle to wear to match the same (now incorrect) angle. How much lower is the back? That looks like quite a gap, and I would have thought that over the width of a lathe bed, to close that gap the rear would have to come up millimeters

Pete

The lathe had the rear way wipers fail but as it's hidden from view by the way covers, nothing was ever done, including using the rear oilers (supposedly ex-gov't lathe). It looks like there was significant wear of the mating saddle surfaces causing the saddle to ride low at the rear. With the saddle casting removed and flipped on it's back you can see a full length wear lip on the rear flat surface and on the front V groove of less than a mm visible. There's a score in the rear ways but apart from that the flame hardening seems to have done it's job, the lathe had a micrometer stop fitted to the front ways and you can see an unworn section of ways, about the last 100mm or so towards the headstock with a pronounced lip which is where I measured the 0.07mm "dip".

Originally Posted by Hunch

How is everyone's 60* section of the vee by the way?

Not with you Bill. Do you mean the narrow face?

Mark, thanks for the pics. My rear way has a gouge as well.

Originally Posted by jhovel

This is the easiest design interpretation of the Kingway tool.
I will be building this one - no castings required.
Joe

Joe, thanks for the pic. Do you happen to have a view of the other side? I can't see any fine adjustment. Maybe you just use the screws at the ends of the vials. Those vials look just like the one on my Starrett 98 series. That is, .005"/ft. But I have to assume they're more sensitive than that.

I have the aforesaid Starrett and a CTC .02mm/m. The first just isn't sensitive enough and the second runs out of range. I kind of need an in between one.

Sorry Bryan, that is the only photo I have of this version.
I have a collection of other replicas and the original Kingway tools - see one of them below.
The fine adjustment is indeed made by the levels only. The only 'tricky' bit is really the two-point universal foot (the tube which is relieved for much of its centre section). If you - or others - are interested in that detail, I'll post a bit more.
Cheers,
Joe

Originally Posted by jhovel

The only 'tricky' bit is really the two-point universal foot (the tube which is relieved for much of its centre section).

You could easily replace that part with a flat bar and two rollers bolted to it. Like the roller bars you saw back in October. To get that 3 point “Kinematic” version, you would want a pair of rollers at each end.

Phil.

Joe, I'd love to see what you've got. And this seems like the right thread for it. Fire at will.

I've been spending some quality time with levels and spreadsheets. Here's the current state of play:




The blue line is the rear way, the purple line is the front way. The green line is the front way, as read from the rear way. That is, by reading across the bed rather than along. Obviously there are minor discrepancies - due to incompetence no doubt - but the overall picture is clear enough. The deepest wear on the rear way appears to be about .03mm (.001"), while the front is closer to .3mm (.012"). Way too much to scrape.

Edit: Headstock now on left, contrary to previous. And yes I did cock up the maths on the earlier chart.

Here are a few more photos:

Originally Posted by Bryan

I need to make a doover so I can survey the front way. It's an asymetric inverted vee.

Bryan,
Did you end up making a doover for the machine's front ways? Would one that is just milled be accurate enough? I'm at a point were i'd like to start testing Blondies ways, the biggest problem here is the width of the bed.

Ewan

Joe, thanks for the pics.

Ewan, yes I did. I made two in fact. They are very quick & dirty. Mk2 will have a foot more like the one in Joe's pics, but I might start with square stock instead of round. I made the foot narrower on the cross tester to better conform to the contour. Don't know if that's daft or not. You'll notice shimming under the level. I couldn't adjust the top for angle or the foot would have cocked. I suppose the ideal support would be four balls.

PS: To better answer your question I don't think there's any need for high precision. Those angle plates were made with a hacksaw and file. And the top plate is a lump of pre-loved 50x6 hot rolled. As long as it's all stable and repeatable.

Hi Bryan,
Shouldn't the diameter of the back contact point be much smaller?

"I suppose the ideal support would be four balls"
Why not two lines and one point like Markos?

Stuart

Thanks Bryan,
You have the same problem as me in that your front V is not symmetrical so you can't turn the Doover around to check it. I was thinking of machining up a 4" length of solid to suit the V and cut it in half. Then fix them together with a piece of rod or bar once tested.

Joe,
Do you think the style of doover you have would work on the LeBlond? I'd be worried about it slipping back and down due to the steep angle of the back of the V.

Also some thoughts on levels would be good, i only have a 6" Starrett #98 which as you say Bryan, really isn't accurate enough over these larger dimensions (i find its fine on the small lathe). Any recommendations would be good, i see that horrible tool exchange site has a 12" M&W, but no indication of accuracy. I always like to buy good quality second hand tools when i can (i call it recycling with style) but wonder if a new Chinese level wouldn't be a safer bet.

Ewan