Lathe update/questions

Hello all,
It appears that my news server and reader were not happy with each
other. Unless I miss my guess, Earthlink's server screwed up, and
Thunderbird failed to gracefully recover. No doubt Google will help
fill the gap.
The machine looks great, but Enco had indeed told me to expect 10 tpi
screws on the cross and compound - in email. I called on Wednesday and
responded in email yesterday; they appear to be chewing on it. They
were upfront in saying that I have 30 days to return the machine, and so
far have claimed that replacement screws are not an option. On the
phone the tech hinted that this might have been and unexpected design
change, and an exchange for an "old one" might be an option, he returned
my call (faster than) as promised and recanted, saying the machine has
always had 8 tpi screws. No offense to the tech, I am not completely
convinced I buy that last part.
Note that I am convinced that the tech who sent the original emails did
so in good faith; he was communicating with someone else who appears to
have made the real mistake of confirming the erroneous.
If there are indeed 10 tpi options, I consider that the way to go.
Let's assume that the original data they provided was nonsense and that
the machine has always had 0.125 dials. The question is what to do:
return an otherwise great buy, or live with the dials?
As I told Enco, if this had happened on a mill ("Oh, I KNOW those are
0.1" - sorry, he really did say that, apparently not appreciating the
irony, but I digress) I would be seriously mad. I work manually, and
(thanks to you guys) have gotten pretty good at it. Being able to
dimension from zero and pick off the last two numbers as a dial reading
is not something I will give up: 0.1 or 0.2 dials are a must on a mill.
But what about a lathe? Staring at the thing, the carriage motion
appears to be course (0.02" gradations), so the precision would appear
to happen on the cross and compound. It looks like a world of working
"against the dials" by measuring and removing metal until the part is
(hopefully) staring back at me, as opposed to zero and trust the
dials. As Harold and others worked hard to help me understand, there is
another realm of trusting the dials to rough and measure to correct, but
0.1/0.2 dials go a long way on a mill. But back to the lathe, IF I am
correct that most work will be measure and remove, how bad would 0.125
dials really be?
What would you do in my shoes? I realize that Enco has not yet
presented options, but given my newbie status with lathes, I need to get
some advice to make a good decision. It is quite possible that I might
have bought this machine knowing about the dials, but we would have a
similar conversation before I did it.
Another question I should ask: do any of you know of a 12x36 (or so)
cam-lock lathe with 0.1 dials? I did some quick checking on the Grizzly
site, and found what looks like the same basic lathe, but no mention
(that I saw) of the screw pitch. That said, their manual is GREAT and
answers many of my "why is this stuck?" kinds of questions.
BTW, I know at least some responses to this type of question lurk in
posts I have yet to see. I will start digging now that I can post again.
Thanks!
Bill
Reply to
Bill Schwab
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Jim,
Jim > DRO
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
Reply to
Bill Schwab
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
Reply to
Wayne S
Wayne,
60 thou!!!! :) How big is the lathe? What kind of work was it designed to do?
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
Reply to
Bill Schwab
And Monarch seems to agree. Despite its 8 pitch cross-slide screw, the 10EE is considered one of the finest small toolroom lathes ever made.
Though, personally, I prefer my Taiwanese HLVH with 10TPI screws. (I can't resist an opportunity to tweak Karl Townsend ).
Reply to
Ned Simmons
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.
Reply to
David Billington
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 8 tpi screw and gearbox you can cut standard and perhaps even metric threads. BG in Iowa
Reply to
MachineShop
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
Reply to
Mechanical Magic
BG,
snipped-for-privacy@hotmail.com wrote:
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
Reply to
Bill Schwab
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.
0.125" dials would be slightly more annoying when roughing off a lot of steel. I take a skim cut and zero the dial, then go in 0.050" per pass and count down 0.100" off the diameter, remembering where to stop. It's 0.025" for stainless, 0.100" for aluminum only because the numbers are easy.
Those are for a 10" leather-belt-drive lathe, BTW. Maybe you could use 0.062" and count 1/8"? You're OK as long as you stop in time, so do whatever your mental math skills allow, then measure.
I do use the dials to measure infeed for threading but it's less than a full turn for 8TPI and finer.
Jim Wilkins
Reply to
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:
Reply to
spaco
I responded too quickly. If the dials agree with the pitch, 8tpi vs 10tpi is about a non-issue. One might "trust the dials" on a mill, but one trusts the micrometer at the lathe.
Reply to
Don Foreman
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.
Reply to
Don Foreman
It's a Feeler.
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I've heard discussions about the relative merits of Feeler vs. Sharp, but I'm not sure it's anything more than a Ford - Chevy thing. I can't find much fault with this lathe, and haven't seen a Hardinge for any less than $15K (which is 10X what I paid) that I'd trade for.
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.
Reply to
Ned Simmons
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 + 0.081" for 3 full turns plus another 0.081. Now it's a slight chore to make that conversion from decimal inches to full turns plus a decimal remainder. Very slight.
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.
Reply to
Richard J Kinch

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