[Newbie] Info About Force International Ml1440gh-1 Lathe

[dave_r_1]

I inherited one of these lathe's from my dad, and am interested in getting into metalworking, for repairing and creating equipment and custom parts for my landscaping business and home.

I'm having trouble finding any information about it, in particular a manual, so I can figure out what all the levers are supposed to do. Googling comes up with a couple of old machines, but nothing at all about this model, let alone manuals.

I'm also considering buying a King PDM30 milling/drilling machine to go with it (on sale right now for $1800 cdn), what models around that price should I consider?

 

[Chipper5783]

Do you have the machine under power? Lathes are all pretty much the same. Especially conventional gear head machines. The upper levers control the spindle speed, the lower knobs control the speed of the feed rod (or lead screw) - thus how much the carriage or cross slide moves for each revolution of the spindle. The controls on the apron engage the various carriage movements.

Read a bunch of the threads here. Focus on learning to do things safely. Start by going slow (both slow spindle speeds and slow in trying new things). Get a few books out of the library. Take a course or two at NAIT (if they still offer anything on conventional machines??) - or other school. Take your time - these machines are really not forgiving of mistakes and a 14" machine could seriously mess a person up.

I'd suggest you hold off on getting a mill. There is a lot to learn on a lathe. Watch the adds and usual second hand sources (for sure, King - and all the other vendors will have sales in the future).

Please let us know how you make out. Keep the questions coming.

Regards, David

 

[dave_r_1]

Yeah, I'm still reading up on both milling and using a lathe. The lathe itself is up and working, I just was stupid and didn't ask my dad to tell/show me more about it. It's been mostly sitting for the past 6 years, only used a couple of times by my dad.

I'm probably luckier than most in that my dad built a good size garage [he was a heavy-duty mechanic and built a garage big enough to do that at home and I inherited the place], so I'm not particularly space constrained, and it also has 220v, so I'm also considering old, used mills.

A lot of the equipment I use isn't designed for people my size (I'm 6'5"), and it makes a big difference when handles and controls are at a reasonable height for me. And then it's also just fun to make stuff that is just right, instead of buying something that just sorta works.

 

[dave_r_1]

First, please ignore how dirty the lathe is. I need to thoroughly clean/oil/lube/maintain the whole thing before using it.

The picture is of the saddle, where I think [from looking at other manuals] the thread dial should be, except the manuals all indicate that it should have 8 markings, with numbers 1-4 for being able to restart doing a thread correctly when the saddle gets unhitched from the leadscrew. But mine only has a single indicator mark, so maybe the 'dial' with the markings maybe was just a plate glued to this [lining up the mark with the '1' on the 'dial' plate]? Does this sound reasonable?

From my understanding of the process, this isn't a critical thing, as for metric threads I still have to keep the saddle hitched to the leadscrew and run it in reverse to go back to the start position and then go over the threads, so it's really just a shortcut for imperial threads. Is this also correct?

 

[dave_r_1]

 

[dave_r_1]

The above are pictures of the main controls of the gearbox on my lathe. The speed control is pretty straightforward, but I'm having a bit of trouble understanding the charts for doing threads.

For example, if I want to make an M8x1.25 bolt, I would (just for configuring the lathe)
-use the top chart, Pitch M.M.
-change the gearing configuration so the top gear has 40 teeth, engaged to the larger 127 tooth middle gear, and so the bottom gear has 60 teeth and it is engaged to the smaller 120 tooth middle gear [middle gear doesn't get swapped, only top and bottom]
-move the levers for the 1.25mm pitch, so I would use A, D, K and U

Is this correct for metric threads?

And for 'standard' threads, say 1/2"-course thread (so UNC, 13 TPI), I would:
-use the second chart, T.P.I. Inch
-change the gearing config so the top gear has 60, engaged to the smaller 120 tooth middle gear, and the bottom gear has 78 [from the chart above the 13 entry] and is also engaged to the smaller 120 tooth middle gear
-move the levers for 13 TPI, so B, C, M, S

Also correct?

And what are the Module, D.P., and the two FEED charts for?

 

[dave_r_1]

And with a bit of googlefu, Module and D.P. (diametrical pitch) evidently are for creating gears.

 

[Steve Shannon]

You are correct on all four counts, but I've not seen module and DP gear pitches shown on a lathe like that. It's still rate of feed and will result in a thread. Nice job figuring it out.


Steve Shannon, P.E.

 

[Steve Shannon]

I just realized having the charts for diametral pitch and module pitch makes it a piece of cake to turn a worm to match a particular worm gear. That's convenient. I don't have the experience others here have, but that's the first time I've seen that shown separately like that.


Steve Shannon, P.E.

 

[Chipper5783]

Looks like you are off to a good start, getting things figured out.

You asked "But mine only has a single indicator mark, so maybe the 'dial' with the markings maybe was just a plate glued to this [lining up the mark with the '1' on the 'dial' plate]? Does this sound reasonable?" Yes, that is pretty much correct. You could even put felt pen marks on there if you like. You could make yourself up a real pretty dial (call it a machining exercise). You could make up a graphic with MS-Paint and print it on a trasparent / translucent media (that's what I did to make up a gear indicator graphic that worked out great). Of course you still need to interpret the dial correctly - not all lathes are the same (when to use any line, when to use only numbers, when to use only even/odd numbers). Or just use it the way it is. With an Imperial lead screw cutting Imperial threads (which is what it looks like you have), make sure your change gears are per the chart, set the knob for your pitch and engage the half nut on that line and you'll be good. If you are going to cut metric threads, then set up your change gears, set the knob like the chart says, close the half nut anywhere you want (AND DO NOT OPEN IT UNTIL THE THREAD IS DONE) - meaning you'll need to pull out the tool and reverse the spindle to go back for another pass. Of course you can cut Imperial threads that way too (whatever works best for you).