The harbor freight mini mill, and other at home equipment. A learn me request.

I think it's been a while since we've had a full on learn me about at home milling equipment.

My buddy Mike has been on a tear lately determined to buy himself a manual lathe. I could see the benefit to it, but for what both of us would use such equipment for, I feel we'd be better served with something that does more. 

I see the harbor freight mini mill as a good looking standalone manual machine. There's room and write ups for adding DROs down the line, but they don't sell them in stores, so getting a good look and feel of them is difficult. I know there's at least one on this forum, but I haven't seen either owner of it talk much about it. 

In the same vein, and similar price point, Keith mentioned desktop cnc machines in his engraver thread. It's been a while since I looked at these, but the last time I did, they were more CNC router than cnc "machine" if that makes sense. Are they capable of working with metal now for under a grand or still just limited to wood?

He wants something to make spindles for tractor rebuilds, so I understand the desire to learn lathe working, and there isn't quite a need for .0005" accuracy, so manual controls should work. 

I'm of the opinion that if it takes up similar space, a more functional machine that we could use to also make things that aren't round would be a better decision, but good machines are extremely expensive, upgrading cheap machines however, is not.

I'm going to guess a Jack of all trades machine is also master of none, I just feel like more functionality is better than prefect accuracy or crazy speed. 

We're not going to run out and buy something, well he might actually, I'm just trying to get an idea if it's worth trying to be cheap instead of waiting for the rare low price on old awesome equipment. There's also a learning curve to consider. Learning to manually run a metal lathe or mill could be a good skill, but, most everything is already computerized. Having worked with cnc routers and 3d printers, I think learning a computerized machine would be much easier, despite the higher buy in. 

I'll follow up with a really grassroots idea I've been kicking around to see what Pierre smarter than I think of it.

I have an Anet A8 3d printer. Acrylic frame, stepper motors, runs on gcode, has exhaustive modification documentation. I also have a plasma cutter, mig welder, and an eBay account. 

I've seen people make metal frames for this printer and leave it as a printer or add a plunge router. 

If I cut the frame out of say 1/4"plate, and welded it together, could I upgrade the stepper motors and carriage and add a Dremel to it? Would a dremel be able to cut through a chunk of steel if you found the right feed speed settings and bits?

I'm thinking this could be the cheapest easiest way, but I feel like I'm missing something in the idea.

Years ago I had access to a mini-machine shop that was used by the owner to make parts for his factory, which was the application of various coatings to various things that he contracted to coat.  There were two lathes and a Bridgeport vertical mill.  There were a few other machines and tools but I mostly used the larger of the two lathes and the mill to make parts for his race car and well mine too.

That was 25 years ago and and I have owned a lathe for the past 20+ years. I have made many parts on the lathe but have had almost no need for a mill.  I suppose that if I had one I would use it but the lathe is used 2-3 times a week to make or modify various bits to fix my cars, my house, or whatever.  

With the right acc. you can  mill small parts on a lathe, but again I haven't needed to do that.

A lot depends on what you want to make.  Large parts fit on a mill where they won't on a lathe but I can make turnings on a lathe that just isn't worth trying on a mill.   

A friend's stepfather passed away, and I inherited his desktop HF mill and lathe. I have not used either, and am very from a machinist, so take what I say with a grain of salt. 

The build quality on both is very low. I think they would be great learner machines, in part due to their shortcomings and sloppiness. I think a great machinist could turn out nice parts, but these are a wax on/wax off proposition to make you either become a great operator, or give up out of sheer frustration.

Watch

this old tony mini-lathe. Not what you asked, but will give you an idea of the build quality

TLDR-if you want to spend a lot of time on set-up and learning a machine's foibles, go for it.

In reply to RevRico :

I owned a turn of the century 1800-1900 mill big heavy belt driven thing that had been converted to a electric motor.  Worn out sloppy thing but very handy   For high tolerance work. I sold it with tooling for the same $300 I paid for it.  
 

I then bought one of the Chinese table top mill/ drill  for about $400 and spent another $1000 on equipment for it. Tolerance was significantly tighter but quickly loosened up and the rest of the time I owned it I spent more time tightening tolerances and readjusting than I actual used it. 
When  I sold it years later  the price of similar machines had more than doubled but even with $1000 worth of tooling all I got read $400 

My friend has one of the HF mini mills, set up for CNC.  He says that if he tunes it all up, he can get sub-thousandths' accuracy out of it.  Temperature changes will effect that though. 

Dr. Hess said:

My friend has one of the HF mini mills, set up for CNC.  He says that if he tunes it all up, he can get sub-thousandths' accuracy out of it.  Temperature changes will effect that though. 

How many hours does he get before it gets out of spec again ?

I'm not sure.  He says that when he wants to do real precision work, he always tunes it up first.  It's sitting in his un-heated garage now, and he said that the temperature changes have thrown it out.  He got heavy into 3D printing and it is just sitting there now. 

In reply to Dr. Hess :

What does "tune it up" mean?  Is that about making sure that the movements are within a gage test?  Or are there parts that need tensioned?

I've honestly never heard that used for machines, but it certainly makes logical sense to do something.

Maybe tuning it up isn't the right machinist term.  We're not machinists.  He says the backlash increases and he tunes the backlash out.  If I recall, he was able to get it down to the ten-thousandths range for accuracy with his CNC stuff.  He used to make molds for hobbyist glass workers.

I have a Certificate of Manufacturing Technology, Advanced Machining, so 2 years of college level machine training.

Tune up means adjusting backlash on all axis and making sure the machine is square using pretty accurate measurements in the basic sense. You can also measure the travel to make sure it is correct, that wear on the ways is not changing the cut.

Lathes are usually set up to cut a long shaft and measurements made to ensure its straight.

Backlash is how far the screw moving the table or carriage turns before that item moves the opposite direction, it can be affected by bearings and wear in the screw / nut itself.

CNC machine use programming to overcome this slack, manually, I personally tend to over shoot, back up and then tighten up the control again, so the cutting pressure is always applied to the same face of the screw, I hope that makes sense, I guess an easier way to say it is I always cut the same direction.

Currently I am moving my lathe which means I have to go through leveling and making it accurate again: ugh.

And yes my shop is a disaster right now, trust me I know....

I've got the HF mini mill, it's an "X2 Clone," there are several resellers of it, HF just being one, but Googling "X2 Mini Mill" will provide a lot more search results than just "Harbor Freight Mill."

I got mine, back in the day before HF put so dang may limitations on their occasional 25% coupons.  I've done a few upgrades, and have a modest amount of tooling for it.  You can easily spend more in tooling than the initial buy-in for the mill itself.  I miss Enco, I used to buy all of my end mills, collets, milling vice, indicators, parallels, etc. from Enco, they always had a great coupon available, and their house branded import stuff, was good enough for me.  I'm getting off track, but Enco was adsorbed back into their parent company, MSC, and while MSC carries a lot of machine tool stuff, I haven't found the deals there that I could on Enco.

Back on topic.

littlemachineshop.com sells a lot of parts, accessories, and upgrades for them.  I've got their gas strut Z axis conversion, that's very much worth it, great improvement.  They make a belt drive conversion, I keep telling myself I'm going to get, but despite everything you read on the internet about shattering plastic drive gears, if you even look at them funny, I'm still on my original drive gears, 6+ years later.

There's some DRO kits, I pieced mine together with iGaging DROs, I think I got them on eBay, they're on Amazon too.  I built my own brackets, and am still using the individual iGaging read outs for each axis, but there's kits to convert the iGaging signal to Bluetooth, and an app for Android that can interpret the signal, so you use a tablet for the DRO, providing a much nicer looking interface.

I'm glad I've got it, it's been handy, but it's not a precision machine, there's no way I'd attempt to do a CNC conversion with the original lead screws, there's a significant amount of back lash.  If you're going to CNC it, you'll want to upgrade to ball screws, there are kits available.

If Dr. Hess' buddy is that precise with his, I'd suspect it's at least been upgraded to aftermarket ball screws, maybe not even the original X/Y table and ways.  You can really spend a lot of money on these, but it gets to the point where you'd probably be better off getting a "real mill."

I'd be happy to answer any questions I can.  I can make something up for the ones I can't.

This topic interests me. I'd love to have a small mill to mess around with a bit.