Lathe update/questions

I am certain you mean well, but it is not going to happen - I have too much else to do with the difference in price, and I am convinced that I have learned a hell of a lot by doing things "the hard way" (not that it is all that hard) on a mill. Calipers and a long-travel indicator? Sure.

Bill

DRO

Bill,

I think the 8 TPI screws are a non-issue on a lathe. I find I just eyeball the cuts until I'm somewhat oversize, then with a digital caliper zeroed on the size I want, measure how much more to remove. Thats when the dials are used. Of course one lathe has very poor dials with a 5 tpi crosslide and an 8 tpi topslide, the other lathe is something like 60 thou per revolution for both. On a lathe, I don't think you will find that you need to make large movements on the dials, just small ones. Hope this helps,

Wayne Sippola

Wayne,

It does indeed. To be fair to myself, I am going to look around again, as well as ask here if anyone knows of 10 tpi machine in the general size of 12x36. It might be that such a beast does not exist. Failing an obvious better deal, I expect to keep the machine. Certainly there is nothing to gain by beating up on Enco and then buying the same blasted thing from elsewhere.

Not that I will go this way, what does a DRO on a lathe instrument? Is it just the carriage and cross travel?

Thanks!

Bill

And Monarch seems to agree. Despite its 8 pitch cross-slide screw, the

Though, personally, I prefer my Taiwanese HLVH with 10TPI screws. (I can't resist an opportunity to tweak Karl Townsend ).

Both my Kerry 1140 (11" x 40") and Harrison M300 (13" x 40") are 10TPI machines. The Kerry has the dial marked for radius and the Harrison diameter although the Harrison is fitted with a DRO so the dial is rarely used.

I think this is a non-issue. As long as the dials read correctly in inches, or 1,000 of an inch does it make a differance? I've owned old old Southbends and now a newer Emco, and you work to measurements at to what you are turning. Worn out or metric dials would be a problem, but old time machinests a 100 years ago or so, produced excellect work using what they had. Sure I set the crossfeed dial at .020 and plan on it being close, but when I get down below .010 or so for a finish cut I'm very carefull.

I'm assuming that you also have both a threading screw at 8 tpi (which is standard) and perhaps a power feed , which is just a hex bar on mine driving the apron/ carriage assy by a gear. I'm sure with the

Bill, My Griz 4003 has a 10 pitch screw on the cross slide, and is marked as radius. The compound and tailstock is also a 10 TPI. The saddle is marked as .010", with numbers at .100" intervals. However, for .100" indicated, it actually moves ~.099". But this is also compounded by the fact that one revolution is NOT an even number of anything, but is marked as .660". It's actually .652" (as measured over 10 revolutions).

IMHO, having ..250" off the diameter is no different than .200" when cranking to a setpoint.

If you are looking at the Griz 4003G manual, yep, that's a good one.

Dave

I lack enough lathe experience to make that call, hence the question. I _would_ make a difference to me on a mill, but the answers are running in the measure/remove direction, and my best guess looking at the machine is that I would end up doing precisely that.

Why do I care about 0.1 (0.2) on a mill? I dimension from zero, and thanks to my 0.1 dials, make (another poster's insightful term) large movements with the dials to get into the right range, and then pick up the last two digits as the dial reading. After some thought, I realized that a mill with 0.2 dials would allow the same trick as long as my eyeballing is good to the "correct tenth." On edge finding, I would set the dial to 100 and be happy.

Again, that's on a mill. On a lathe, it seems unlikely to have one zeroing cover all, especially longitudinally. Using the dials only for small corrections, 0.125 dials would probably not bother me.

Also, the machine looks great, the price was attractive, and it is in my garage and perched on its stand. The question I have to ask myself is whether I would have bought it had I known up front about the dials?

Understood. With a measure/correct approach, the dials should be fine.

Another option would be (just guessing) to zero either by touching something of known diameter (seems sketchy) or by turning something small and measuring the result. Any other tricks?? Regardless, I could then dimension from multiples of 1/8" in the correct direction to have the dial readings be obvious from the drawing. That assumes that most shapes would be simple (not true on a mill) so I would be doing such craziness for only a few different diameters.

The above might sound silly, but I figured out a similar trick on a mill, and it worked wonderfully. The problem was to use a boring head to take a divot out of the top and bottom surfaces of a square tube; the sides were to remain untouched. By drawing a line a few inches in negative-x from the tube, I was able to dimension the location of the center of the boring head to make the cut. It has been a while, but I probably set the head by cutting scrap to get the 2.010" or whatever it was that I needed. With that done, it was just a matter of eyeballing the head location and trusting the dial.

I'll brag about the lathe a little. It uses a slot in a separate shaft for carriage and cross feed; AFAICT, the screw is used only when threading, which is the right way to do it.

It is primarily imperial (which is what I wanted), and will cut some metric threads with change gears. I barely understood a word of it, but last fall somebody mentioned that with the change gears, I should expect to have some trouble chasing threads, but that it can be done. I look forward to someday understanding what I just said :)

Again, the question now is whether I would have bought this machine given correct data. Since it sounds like the 0.125 dials are not a serious hassle, I will probably conclude that I saved enough money and got a good enough machine that I probably should just keep it. If however, I find a 0.1 machine for similar money, I might owe it to myself to get what I thought I was buying.

Thanks!!

Bill

My Hardinge HLVH is .200 per rev.

Gunner

My first Sears lathe has 24TPI leadscrews, 0.04167" / rev. It didn't originally have dials. I made some but found out I really didn't need them.

I don't depend on the crossfeed or compound dials for 0.001" accuracy over a long distance very often because the SB lathe has too much give on a heavy cut. The procedure that gives good results is rough to within about 0.010", [stone the bit], take a few thousandths finish cut and measure, then another about 0.002" over final size and check carefully for taper etc. From there it's honed broad-nosed tools, filing, fine sandpaper, whatever it takes to make the part good enough to work.

I take quick measurements with a dial caliper while roughing and only use a slower mike for the finish cuts. This is a good use for a - cheap- dial caliper since it might be damaged by chips.

Those are for a 10" leather-belt-drive lathe, BTW. Maybe you could use

I do use the dials to measure infeed for threading but it's less than a full turn for 8TPI and finer.

Jim Wilkins

I know you said that you didn't want a DRO, but I have one on my old mill and I haven't looked at the dials (except Z) since. So, if you do get stuck with the 8 TPI, that's what I'd do. It's not a "great deal" if it isn't what you want.

Pete Stanaitis

-----------------

Bill Schwab wrote:

That would drive you nuts the entire time you owned that lathe.

I responded too quickly. If the dials agree with the pitch, 8tpi vs

Is that a Sharp by any chance?

I saw one a few years ago and was impressed. Beautifully built. I want one.

My "take" on this is that if you like everything else about the machine, .125 dials and 8-pitch screws are immaterial. I think a DRO is about indispensible on a mill (sorry, Harold) but I don't have one on my lathe nor lust for one. I only use the dials on a lathe for rough cuts and small increments anyway; the truth is in the calipers for roughing and micrometer when getting close. I use the fine gradations on the dial to move in a thou or two when "on final" but those would be thou on either type of dial.

The dials are seldom right anway, except perhaps when using carbide on stainless, and mine is a fairly large and rigid machine -- a 15x50 weighing at least a ton. The mike is always right.

It's often rather awkward to measure in-process on a mill, usually quite easy on a lathe.

It's a Feeler.

The only problem I've had is the feed motor was intermittent when I got it. There were a couple open connections to the commutator, which I was able to repair. I think I've seen new machines that were advertised as having a Bodine feed motor, like the Hardinges, so this may be a common problem.

It'd be interesting to know how many actual mfrs of these knockoffs there are. I've seen them branded Sharp, Feeler, Vectrax (MSC's house brand), Wilton, Ganesh (despite the unfortunate choice of an Indian name, it's apparently Taiwanese), and probably a couple others.

It was and it always did.

I own this lathe. I use it every day. This lathe is a friend of mine. It turns metal from base-priced stock to parts worth literally their weight in gold (at least in the stuff I make with it).

The 1/8 dials are really a very slight consideration. If you're not a whiz at arithmetic-in-your-head, or at least not reliable enough that you can trust hours of work invested in a part to getting it certainly right, then you do what I do:

You are dimensioning the process cuts on your drawings, right? Not just finished sizes? When you have a process step like a feed of 0.456, then you do the calculation and pencil it next to that dimension as "3t +

One of the principles of metalworking is the discipline to draw and dimension things properly and fully. Otherwise you can't make anything better than what you can conceive in precise detail in your head, which isn't much. And these dimensions are almost as easily rendered as units of 1/8 turn versus 1/10 turn.

Now I did finally upgrade to a DRO, but that was a matter of improving productivity, not capability. The DRO lets you set up faster, and reduces the risk of error that wastes a time-invested part, but it is all possible with dials, even if they're calibrated in microfurlongs.

I suspect your missing component is just a pencil.

How many grauations on the cross feed inch dial?

Tom