Machining metal parts

[etpm]

Let's talk a little about buying a machine tool. The truly most versatile machine tool is the lathe. But to take advantage of this you must be experienced using the lathe. For an inexperienced user, a beginner using machine tools, a knee mill, also known as a turret mill in the Bridgeport type mill configuration, is probably the most useful, though still not the most versatile, machine tool to buy. And this is because lots of turning work is not usually required to make or repair most of the stuff for the folks reading this.
So a mill is to be the first purchase. Once again versatility is in the picture. But this time versatility and usefulness go hand in hand. The most useful will also be the most versatile. And the most versatile will also be the most useful. In my opinion, as a machinist with over 45 years experience machining stuff, getting a Bridgeport type mill is the by far best decision. Even for someone with limited funds. Especially for someone with limited funds. I know, prices are different all over the country. Still, it really makes a huge difference, more than offset by the price difference, to have a machine tool that can do so much more than a lesser machine.
If you can, then you should, look at several machines before buying one. If you can pay a machinist to look at a particular machine that's good. Maybe even better is if you can get a machinist to show you a good and a worn machine side by side or at least close is proximity time wise. Then you can look at machines on your own and not pay for every mill you look at. Maybe then you can make the purchase decision on your own or at least whittle down the prospects so that your paid consultant doesn't need to be paid that much.
If you are for sure going to buy a mill then you will need some inspection equipment. You will need a test indicator And a magnetic base for the indicator. And a 1 inch travel indicator. These same inspection instruments are also extremely useful for evaluating the condition of the mill you are thinking about buying. You should then buy these for yourself ahead of time. Learn how to use them. This may make it possible for you to evaluate a machine on your own. Doing your own evaluation, if you are confident in the use of these inspection tools, may make it possible for you to take your time evaluating a machine, to really take your time, and so make a better decision.
I know, there are other folks with different opinions. They mean well, as do I. And there it is.
Cheers,
Eric

 

[jthibodeau89]

That's a nice piece

Looks like it has an extra long y-axis compared to most knee mills

Its 10x54 bed instead of 9x42.

 

[LD1]

Its 10x54 bed instead of 9x42.

Still just looks like it has wat more travel than most knee mills I see. Like almost more travel than the head can compensate for by running it in and out

 

[jwmorris]

The truly most versatile machine tool is the lathe. But to take advantage of this you must be experienced using the lathe. For an inexperienced user, a beginner using machine tools, a knee mill, also known as a turret mill in the Bridgeport type mill configuration, is probably the most useful

I can’t see being without either as both are pretty important in my projects. Other tools as well.

As this is the welding forum, the pantograph I built is one of the more handy projects I have made. Saves hours of time.

Wrap your head around milling something like this out, without a CNC. Now think about shaping it from plastic sheet then duplicating it in steel, one after another, using the torch or plasma you already have.

Other than boring and turning lathes can also thread ID as well as OD and you don’t always have to single point.

Drilling and tapping can be done on drill presses as well, some are made just for the job and in today’s CNC world can be picked up for scrap prices.

That said, none of the above can replace a good mill, the machines complement one another.

 

[3Ts]

I've been following along on this discussion and have looked up the things you've mentioned that I didn't know about, such as the coaxial indicator. I've also been looking at the youtube videos and have learned a bunch. I want to get a "reasonably good" machine. I'm in the camp of a newbie staying away from "cheap" (like harbor freight) machine tools because they'll only get frustrated. I'm reasonably good with wood turning and have good quality tools in that area, I've given demos using harbor freight lathes and can make it look good. BUT, I know the tool limitations and can accommodate them. For example, repeatability, on my equipment I can take the work off the machine and put it back on and it is still lined up properly, can't do that with cheap tools so you have to plan your work differently. For my wood working, Grizzly is the brand on most of my tools so I'm looking at them for the metal working, but I wonder if it's good enough. Tolerances on metal working are much tighter than on wood working.

After seeing the videos on how DROs are used, that seems that it would be in the really, really should have category. I'm also aware that the recommended 1st machine tool is a lathe, but I can't imagine what I would do with it so I'm looking at a mill.

 

[GeneV]

A mill or lathe w/o a DRO, it's like multiplying compound fractions w/o a calculator. There's no way I'd go back to working without a DRO!

BukitCase, that Griz of yours is a perfectly fine machine. I have limited head room in my shop, so needed a more compact mill myself, bought a Precision Matthews PM935. A Taiwan knee mill, maybe has a little more capability than yours, but not by much.

Lathe, mine's a Prototrak toolroom CNC lathe.

 

[BukitCase]

Gene, thanks; so far it's not dissapointed. I generally try to buy tools that I am the limitation, NOT the tool - so far, so good. When I was looking, I had the good sense to listen to someone who had BTDT and worn out the T shirt, so my choice of mill has the power up/down on the head, square column, powered X axis. So far I've not been sorry.

DRO - couldn't agree more. I have all the components to implement, but it hasn't reached the top of the (excruciatingly long) project list (the GOOD news: boredom will NOT be happening before somebody "pats me in the face with a shovel", so I'm calling that a "win".

For those who aren't afraid of tech, you can save around $1000 on a 3 axis DRO - here's a way to do it wireless (sorta) and you can add the lathe DRO later for just the cost of the scales and wifi pieces

DIY DRO Project

Blog dedicated to DIY digital readout TouchDRO and other hobby machining and engineering subjects.

www.yuriystoys.com

I haven't been on his site for a while, but I can't imagine when Yuri sleeps; seems like he's constantly answering questions and adding features to the app... Steve

 

[GeneV]

I dunno about Yuri's kit (sounds like he's from my part of the world, per his name), but I installed DRO kits before, ones I bought from Shars. They weren't all that hard to install.

 

[LD1]

A mill or lathe w/o a DRO, it's like multiplying compound fractions w/o a calculator. There's no way I'd go back to working without a DRO!

BukitCase, that Griz of yours is a perfectly fine machine. I have limited head room in my shop, so needed a more compact mill myself, bought a Precision Matthews PM935. A Taiwan knee mill, maybe has a little more capability than yours, but not by much.

Lathe, mine's a Prototrak toolroom CNC lathe.

Agree they are nice....but It would be much easier to give up my DRO on the lathe.

For the mill.....it is SOOO much faster precisely locating everything, drilling holes in a specific pattern, depth of cuts, etc.

But the lathe.....I can use the single hand wheel for each pass which is spot on. And if I need an exact measurement for the carriage, I can simply stick on my magnetic dial indicator.

 

[jthibodeau89]

Still just looks like it has wat more travel than most knee mills I see. Like almost more travel than the head can compensate for by running it in and out

@LD1 I'm sorry, i read X axis when you said Y axis. The travel on the head of this mill is 24". I keep it set near the mid point