Buying my first lathe

[Bob Korves]

Well, I guess that's the $0.20 question, innit .

Well, there are no standard fasteners I am aware of that would need those threads. That is not to say you might not want to make one for some reason some day, but I cannot think of why you would. And you could make those threads, by simply changing the change gears for that once in a lifetime job... It looks to me like the designers did a fine job on that lathe, making all the common pitches available at the simple twist of a few dials.

Ignore 1% solutions, and concentrate on the 99% solutions...

 

[mikey]

The feed clutch is useful in that it will theoretically slip before the feed gears break on an ambitious cut. The carriage stop is a very useful accessory, although an indicator is more accurate for positioning the stop. They are not usually used together, although they can be.

 

[Siggi]

Well, there are no standard fasteners I am aware of that would need those threads.

Sweet - so changing gears for imperial threads would be a "once in a blue moon", e.g. the gearboxen aren't a significant feature difference.
Thanks, this is the sort of thing that's hard to assess as a raw n00b.

The feed clutch is useful in that it will theoretically slip before the feed gears break on an ambitious cut. The carriage stop is a very useful accessory, although an indicator is more accurate for positioning the stop. They are not usually used together, although they can be.

Hey Mike, I'm a n00b, so please forgive the stupid^Wignorant questions, but how would the stop be used if not on power feed? Hand feed, reverse feed from a shoulder?

The PM1236 manual has this verbiage:
"The clutch shown in Figure 3-15 disengages the power
feed if the carriage or cross slide hits an obstruction
when power feeding, thus minimizing the potential for
damage. This could be the result of either an accidental
event, or deliberately stopping the carriage at a precise
location set by the stop, Figure 3-16."

 

[mikey]

While it has many uses, a carriage stop is typically used to turn or bore to a precise depth. Most commonly, you would set the stop in the desired position and power feed almost up to the stop and disengage the power feed, then manually feed up to the stop. This has several benefits: one, you don't knock the stop out of position, two, you don't stress your feed gears, three, you don't wear the feed clutch prematurely so that it eventually slips on standard cuts. You can use a stop in combination with the feed clutch; that's up to you but most of us don't do that.

Most of the time, you will use your saddle handwheel or a DRO to move the saddle to the desired location and then move the carriage stop into position and lock it down. If I need great precision, as in a precision bore, then I trust an indicator before I would trust a micrometer carriage stop. Anyway, then you move the saddle back, engage your cutting tool and cut up to the stop.

My Emco 11" lathe has a feed clutch at the end of the drive rod. I think its a useful thing to have to save my gear train in case of an accident but I don't abuse it. My manual states it can be used with the stop for precision boring but doesn't mean I'd do it that way. The manual also says the stop can be used to prevent a crash when the lathe is used by an apprentice. Interestingly, I do use it that way when I'm machining up close to the chuck (feeding manually). Here, I mean when the cutter is inside of 0.005" of the chuck jaws and a crash would be catastrophic.

I guess my point is that the feed clutch is useful in a crash or if taking too ambitious of a cut; it will slip before excessive damage is done to the gear train. A carriage stop is a must have for precision turning and boring. Using them together can be done but it can also be done manually, with less wear and tear to your lathe.

 

[Siggi]

While it has many uses, a carriage stop is typically used to turn or bore to a precise depth.

....

I guess my point is that the feed clutch is useful in a crash or if taking too ambitious of a cut; it will slip before excessive damage is done to the gear train. A carriage stop is a must have for precision turning and boring. Using them together can be done but it can also be done manually, with less wear and tear to your lathe.

Hey Mike, thanks for taking the time to 'splain in detail - clearly I have a lot to learn. With a CNC and a lathe I can be TWICE as aware of my ignorance per time unit .

 

[mikey]

Hey Mike, thanks for taking the time to 'spain in detail - clearly I have a lot to learn. With a CNC and a lathe I can be TWICE as aware of my ignorance per time unit .

Trust me, Siggi, we are all still learning - when we stop, we're dead!

 

[Siggi]

Hey y'all,

in case you're keeping score, the PM1236 is the winner for me. The D1-5 chuck is not an advantage for the Grizzly, and the feed/speed gearbox on the PM is quite adequate. As it's oil-filled may have better lasting power to boot. The foot brake, feed clutch, cast iron stand and tooling win the day.

Note, however, that I've been in email correspondence with Grizzly, and their sales folks do claim the stand you get is cast iron. For anyone who happens upon this thread, if you're planning to buy the Grizzly G4003G, have them confirm that the stand is cast iron as opposed to welded steel. I have a hunch they'll ship you the cast iron stand if you very pointedly ask for it, or otherwise you can chew them up and hit them for a discount if they end up shipping the welded steel stand...

The next question is what, if any, of the offered additional tooling to throw on the order.

Siggi

 

[mikey]

I just looked at the difference between the standard and preferred packages and for $300.00, you just cannot beat what they're offering. Just the QCTP and foot brake alone are more than worth the cost. I'm not sure that the coolant pump is something you'll use. I have the hook ups for one and have no intention of dealing with the mess but that's me.

I personally would prefer an aftermarket live center (Skoda, Royal or equivalent) and an Albrecht keyless chuck but that can come later when funds allow. At least the stuff they include will get you started.

I think a DRO is a good thing to have. They are asking for over $600.00 to install a glass scale DRO. I might forego that and look into other options. DRO Pros will get close to that price and include magnetic scales so something to think about.

If you haven't run a lathe before or do not own cutting tools then they're offering that BXA turning/boring set and the threading tool set at a very good price. It includes enough inserts to keep you cutting for a very long time. The turning and boring tool holders are of the SCLCR type, probably the most popular configuration in most hobby shops. Inserts are readily available for reasonable prices on ebay. The threading tools use an ER-16 insert, also very popular and Carmex inserts for these are fairly cheap and easily obtained. For the cost they're charging, its hard to beat and you'll need these tools. Of course, you can go cheaper by using HSS tooling; HSS has many advantages over carbide but it requires you to know how to grind those tools and that can come later.

So, if this was me buying this lathe, I would go for the preferred package and also buy the turning/boring tool and threading tool packages. I would buy a DRO from DRO Pros or some other source and install it myself.

Now I'll step aside and let the PM lathe owners tell you how it really is.

 

[Siggi]

I just looked at the difference between the standard and preferred packages and for $300.00, you just cannot beat what they're offering. Just the QCTP and foot brake alone are more than worth the cost.

Yeah, the foot brake is a big selling point for me for this lathe, and the preferred package is the way to go.

So, if this was me buying this lathe, I would go for the preferred package and also buy the turning/boring tool and threading tool packages.

Thanks for the detailed explanation again - makes sense to me to get the tooling I'd need to start making mistakes right away .

I would buy a DRO from DRO Pros or some other source and install it myself.

Yeah, a DRO will have to wait a bit, and it looks like it'll involve a bit of research to figure out what's what there...

 

[Cheeseking]

Agree 100% foot brake is a must. That and if possible 3 phase powered so you get instant stopping/reversing.
Haven't seen the tooling in question but I do have a DroPro mag scale unit (el400?) and it has been awesome. Not mandatory but if you have the scratch its a great add on. Be aware tho its not open the box and plug in deal. Depending on the machine, dro install can be straightforward or quite challenging. They give you some standard brackets etc but more than likely you'll need to customize or make your own.