Harbour freight 44991 mill/drill

im gonna rant for a minute... ive been thinking about this little mini mill this evening while waiting for the kiddo to fall asleep... plastic gears....... plaaaaastic gears.
let me say that again, maybe itll sound better.... plaaaaaaaaaaaastic gears.
nah man... just doesnt sound right.

its like you bought a cheap import car. standard AM/FM radio no cd, roll up crank windows, standard transmission, the junky trunk latch that wont latch in 6 months, and sheet metal body that will rust... all of which suck, but work. they do their job, even if for a limited time. but you can abuse them and they will work... but then they go and do something asinine like install a wooden engine. yes, a wooden engine. it makes just as much sense as plastic gears. i mean, there are a plethora of replacement parts and designs to eliminate the plastic gears. but no, SEVERAL different companies sell this same mill, and for what i can imagine has been for a decade or whatever, and theyve never clued in that its just no good...

everything about this lathe is cheap. the milling in the T slots looks like it was done with a potato, it looks like they dunked the whole unit into a vat of potato grease, the hand cranks are solid with no potato detail, the bolts are cheap, and its crooked...potato... BUT IT WORKS. its all metal, the electronics are even decent, but then they go and install PLASTIC GEARS.... like seriously. you could have cheaped out on ANYTHING else, and gotten away with it. but instead they installed .... plastic gears.
man, that just grinds me...

/rant
 
OK, rant accepted. But as I've posted previously, I have just about the same mill. Mine's a Harbor Freight. I ran it for quite a while (at least a year or two) without any problems with the gears. The main reason I bought the LMS belt drive kit was that it was supposed to be a lot quieter than the gears. It was! And yes, you can get metal gears to replace the plastic ... but they're noisier yet. Under normal circumstances, the plastic gears are just fine.

You just got caught with the wrong combination of an aggressive (fly) cutter and Z axis backlash (or what's known as the infamous mimi-mill head drop). I don't think I've ever used a fly cutter with my mini. Never thought it had the power for that kind of cutter.

PS - I definitely agree with you about the factory grease. My own guess at the ancient Chinese recipe for "Cosomorene" is that they boil up a bunch of used motor oil and axle grease in a 55 gallon drum, then throw in a couple of old tires to thicken it up. Stir well to dissolve the rubber, then slather it on :)
 
I dunno man... as soon as I took it apart I could see the weakness. Right where the key way is. I think it broke too easily... it was a tiny fly cutter. Maybe I'm bitter... no, I know I'm bitter. But at what? The machine? Maybe. Likely mostly myself. Sometimes I'm a little too gung-ho before I know enough. Typical mistake.
 
Shawn, don't be bitter my man,it is just a hobby, as you said it yourself, this mill is supposed to be for your enjoyment so don't let it be source of aggravation,the weakest link in this type of mill (as you found out) is the plastic gears, the fact that you broke your is nothing unusual ,they would have eventually broke anyway, in fact it was probably a good thing that you broke it prematurely, once you have the metal gears on,you'll be good to go for a long time.

That mini mill is no slouch,it can produce great stuff, a lot of hobby machinists use them and are quite happy with them as long as you are aware of it's limitations you'll be fine, I know I own one but with a brushless motor, it is essentially the same mill though.
I like your idea to tram your mill/adjust the gibs while you are waiting for the gears to arrive, did you already install the Igaging DRO? that should take a couple of days,I just finished installing mine, had a blast doing it.
 
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After I spent most of last night fixing the dove tail (the x carriage jams in the last quarter of the dove tail) don't get mad, I wound up using some lapping compound cause I couldn't file out the step.
Smooth now.
Since I had the carriages off I mounted the x dro. Almost done that, stopped cause Irma's 1am and I got told to go to bed. Lol.
I'll finish odd the x & y tonight. Won't do the z till I get the gears cause no sense in putting the head back on till I have the gears.
I was enjoying cleaning and deburring. I am enjoying it, just the stupidity of such a weak component I'm such an important spot bothered me.
 
After watching a few youtube videos on how to install aDRO on the X axis, I found out that the position of the digital reader is very important since it could hit the column if installed in the center(it should be off center more toward the left of the column) , I suggest you do a dry run before finalizing the installation by moving the Y saddle all the way back toward the column while watching the reader in case it hits the column gosset.this video (at about 3.52) explains what I'm talking about:
 
I had already anticipated and expected I'd lose x travel due to the reader. It was either that or put it on the front and cover all the gib screws and whatnot.
I wasn't horribly concerned cause the vice I'm gonna use sits pretty far back on the table. But I'll give that video a watch and consider it.
 
I centered the read head on the x axis scale and removed the left side dust cover screw and installed a stud and nut. Adjust to stop saddle before the scale read head hits the fuselage bracket, the nut locks the dust cover bracket. No chance of damage to the scale that way.
saddle stop.jpg
 
That's a great idea.

Nice little drawing, too.
 
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