[nateman_doo]

My mini mill broke. I was feeding copper into it, and it pulled the material, out of the vise a bit, and now it sounds like some gears are messed up inside it. Motor is fine, but it doesn't spin the collet.

I looked at the manual to see how complicated it was to open up and look inside. Looks VERY complicated to me. I have the machine about a week from Harbor Freight. Should I return it to them, or try to fix it myself?

[Dano523]

You have a X-2 and blew the plastic gears, which happens all the time. And no, it will not be covered under warranty.

Since you need to true the head anyway, now is a good time to update the machine to belt drive, hence pull the head, strip out the plastic gears, and install the belt drive system then true the head when it all said and down.

And trust me, in good time you are going to learn to strip the machine down to pieces anyway, so nothing like the present to learn how.

http://littlemachineshop.com/product...2560&category=

As for just replacing the plastic gears, don't waste your time since you will just end up blowing them up quickly again as well.

[nateman_doo]

PLASTIC GEARS?!? what the hell were they thinking?! (aside from preventing catastrophic failure like what could have happens if the gears were metal)

So when you say its not under warranty, Harbor Freight won't take it back? Its less then a week old. I was hoping I could raise enough hell with them and they would replace it under their 30 day customer satisfaction guarantee. (Which I will likely still pursue in the morning)

Does the belt conversion come with instructions? Taking things apart comes naturally for me, but putting them together, thats a whole different story. I really would like to convert this machine to CNC, will this belt kit help doing that? Is it one step closer to that end state of CNC?

I appreciate the help!

You have a X-2 and blew the plastic gears, which happens all the time. And no, it will not be covered under warranty.

Since you need to true the head anyway, now is a good time to update the machine to belt drive, hence pull the head, strip out the plastic gears, and install the belt drive system then true the head when it all said and down.

And trust me, in good time you are going to learn to strip the machine down to pieces anyway, so nothing like the present to learn how.

http://littlemachineshop.com/product...2560&category=

As for just replacing the plastic gears, don't waste your time since you will just end up blowing them up quickly again as well.

[mrcodewiz]

You want the belt drive conversion - cnc or otherwise. It was the best mod (other than CNC) that I ever did to mine. You blew the gears - nothing to blame HF for. You just got it out of the way a little quicker than most people.

[photomankc]

Not sure if you can raise enough stink or not but the machine is not at fault here. You didn't secure the workpiece well enough or you took too deep a cut for the machine and setup and that's why it went south on you. The gears did their thing. They broke before something more dramatic took place. That's the reason (they say at least) they are plastic.

Not to come down on you or anything, I just almost had the same whoops tonight when I accidently took too deep a cut by 2X. Honestly it wouldn't be fair in my opinion to try and put this off on Harbor Frieght. I think the belt drive is pretty straight forward to get installed and almost everyone that does it loves it. I'd also go that route rather than hunt down and wait on the replacement gears.

[jalessi]

Nateman_Doo,

Little Machine Shop has metal replacement gears for $40.00

See the link below:

http://tinyurl.com/2vndpoc

Jeff...

[nateman_doo]

So I called Harbor Freight, and they didn't bat an eye. They RMA'd the machine. I couldn't be happier. This is the reason I like buying from large companies. I know the gears did their job, but somewhere in the manual it should state that aggressive work may damage the plastic gears inside it. A little warning goes a long way. I apologize, you gotta cut a rookie some slack.

I know I am very new at this sort of thing, but wouldn't it be better to keep all the gears inside the machine metal, and just keep the top gear that makes contact with the motor plastic? That would be a much easier repair, and they could include a spare gear. Since the motor and that gear are outside, it would make life so much easier.

Since you guys helped me out, I am now aware of the machine having plastic gears and I will be far more careful with it. I plan to purchase that belt drive kit, but also looking to have CNC capabilities. I have posted here before on it, but still the info is a bit much to absorb. I tend to learn as I go, and installing parts works best, but I do like to try and absorb what I can from reading.

As I understand what I have been reading about CNC conversions, you need the following:

1. 3 motors to spin the X, Y, Z travels
2. Controller type box for all the motors to be connected to
3. A power supply for the motors/control box;
4. A computer to run the software
5. The software itself.

Am I understanding this correctly in that is all I really need? I was hoping to find an idiots guide or "you need this this this & this" type of info. Thanks guys of all the help!

[photomankc]

To each their own but I would much rather have at the minimum purchased the LMS metal gears and got back to work than pack up, return, and then re-clean a complete replacement. That's a fair bit of work not to mention that some machines are better than others with straightness of the ways and travels, flatness of the table, and so forth. If those are really good on this mill it would be disappointing to find they were not so good on the next.

For CNC:

1.) Yes, but there's where the devil comes in the details. You need a mounting system you can make up, shaft couplers for the drive that flex enough to allow for minor miss-alignment. You need bearings and the ability to make the tight tolerance holes for them. Most people go with complicated ball-screws to eliminate backlash as much as possible.

2.) Yep, you can go low cost with Hobby-CNC or high-end with Gecko drivers. Kieling is in between.

3.) Simple here is good. Plenty of amps 36 to 48 volts or more if the driver will allow it. Don't need regulated supply but it's OK if that's what you got.

4.) Don't get a junker, it needs to be a speedy system to generate the 3 pulse trains in real-time at a rate that allows for good speeds on the mill. Doesn't need to be brand-new but something contemporary.

5.) Software is where the costs really get going. Mach is rather inexpensive but the CAD/CAM software to convert drawings to G-Code for Mach can really add up. Lots of choice though from very limited and free to full featured and as much as a decent used car.

Check out hossmachine.info for some fantastic information and plans for getting an X2 CNC'd.

[nateman_doo]

Very true, but I only used the machine less then a week, and I already cleaned it up, and packaged it up even before I made the call to them. I would agree some machines are better then other, and based on how much wiggle room was on the X axis, and how hard the Z axis was to engage fine/rough, and the Y axis left much to be desired, I can only hope the machine I am getting is a bit better. No matter how much I adjusted the tension on the slide, it would still wiggle within a few passes. I saw an "upgrade kit" on the LMS sight that had some much nicer set screws that had teflon or something that would prevent them from slipping and getting rid of the nut around them.

thanks for the CNC info! I have been reading Hoss's page for the past few days. Slowly (very slowly) absorbing the info. I plan to make the purchase around October, and am just in the planning stages.

Seems like there is so much to absorb. Do I have the overall concept of what is required as far as major end items?

[knudsen]

wouldn't it be better to keep all the gears inside the machine metal, and just keep the top gear that makes contact with the motor plastic?

All plastic, I believe, except the motor gear: http://littlemachineshop.com/product...First=G&Last=I

[nateman_doo]

All plastic, I believe, except the motor gear: http://littlemachineshop.com/product...First=G&Last=I

If only the top gear was plastic, then that would be the only part needing replacement right? The plastic gear would self-annihilate when something binds, and then you just take the top off, and your ready to replace instead of opening up the entire machine. My theory at least.

side note:
I am designing a 2' x 4' made of MDF with 4x4 posts & 2x4 braces as a dedicated table for the mill.

[Dano523]

Want the truth,

If you plan on doing any real work with the machine, you are going to be blowing up gears left and right. Three days in not bad, and I think that I blew the gears in my machine something like the first day by running a 1 1/2" insert cutter for a finishing pass.

Furthermore, since the gears are the weak link, when you do go to a belt drive system, then you can now put the motor to full use with all it's power, instead of it currently being run in a crippled state to work with the plastic gears.

And yes crippled state since if you look at the rating on the motor (120v, then check the output on the board, you will find that the board only puts out 90v when maxed and kicks out well before the max motor amp rating as well).


So, if you plan on returning the machine since you don't want to have to deal with plastic gears, then use the money you get back to buy a SX-2 instead (bushing less motor and belt driven from the start).

[knudsen]

If only the top gear was plastic, then that would be the only part needing replacement right? The plastic gear would self-annihilate when something binds, and then you just take the top off, and your ready to replace instead of opening up the entire machine. My theory at least.

There's a plastic idler between the motors steel gear and the spindle gears that explodes first. It is replaced pretty much as you describe. It's the fuse If they had the foresight to ship a spare, you would probably have already replaced the broken gear and be up and running now Weak gear train, IMHO. I don't buy it that it's supposed to be a mechanical fuse. Weak design in my view. You can buy metal gears from LMS if you desire. If you are fairly careful in use, the gears don't break that easy. I broke one early on, ordered two so I had a spare, never broke another (tap wood).

side note:
I am designing a 2' x 4' made of MDF with 4x4 posts & 2x4 braces as a dedicated table for the mill.

Sounds plenty sturdy to me!

[nateman_doo]

that single gear that is touching the motor sprocket is just fine. The gears inside are whats messed up.

[knudsen]

You da man, nateman_doo! I only managed to grenade the lower gears when I crashed mine! :rainfro:

[mrcodewiz]

I probably ran mine for a year before I upgraded to the belt drive and I never did break the gears. Maybe I am overly conservative.

[Crevice Reamer]

Hi Nateman.

Were I you, I would return that HF mill for purchase price, and then put that amount towards buying the far superior SX2L:
http://littlemachineshop.com/3900

This mill comes already equipped with belt drive, plus larger table/base and larger travels. It also has a more powerful BLDC motor.

CR.

[nateman_doo]

Crevice, 2 reasons I will stick with the HF model. First, the LMS version is not in stock, and I need to be operational quickly. Also I got the HF on sale, and used a 20% off coupon. Was something close to $400 even (shipped too!)

I just built my table for it. It is around 3 feet high, with 4x4's as legs, 2x4 bracing, and 1.5" plywood table top with 22 gauge steel layered top, and 1.5" plywood bottom. I plan to make a plexi enclosure so I can make a spray liquid cooling system.

[nateman_doo]

Here is the milling table I built.



double layered .75" plywood top, and bottom. 4x4 posts as legs with 2x4 bracing under the tabletop.

I will wrap around more plywood when it comes time to go operational. I didn't want to do that just yet because I want to see where things will end up going.

It is sitting on some 2" casters to roll around my basement easy, and when it comes time to use it, I have some of the leftover 4x4 post to elevate the table off the legs, and a few bags of concrete to add some weight to the table.

The overall dimensions are 36" tall, 48" wide, by 24" deep. I will use some contact cement to secure the 22 gauge steel top for the table.

Future plans are to enclose the entire table in a plexi box, so I can make a coolant dispenser, and reclamation.

[nateman_doo]

Motors with powersupply and the controller box:
CNC 4 Axis Package with 425 oz-in motor and KL-4030 Bipolar
Driver with 36V/9.6A Power Supply: $479 4 Axis System Specification

[4th axis for the future] How do I mount them, does it come with all hardware?

So once I have that, I need the ball screws, computer, & software?