Harbor Freight 42976

[Dead Nuts]

Last Saturday I attended a Model Engineering Expo in Toledo Ohio. I ran into Rick of the famous Rick-o-matic fame and showed him pictures of my conversion of a Harbor Freight drill/mill to cnc control. He urged me to post pictures here. So here it is.

Per instructions learned from these Internet forums, the first thing I did after bring home my model 42976 mill was to totally disassemble it right down to the basic screws. I found one thrust bearing assembled wrong and straightened it out on reassembly. While apart I removed all the burrs, then measured each piece and entered it into a AutoCAD 3d solids model. Then I'd plot out each piece and cut out the paper model and place it onto the actual piece to be sure I had made no glaring error. Once I had it back together, I designed the NC hardware to match the motors I picked up on e-bay. Then I went to a friends house who had an NC mill and we made the parts. Anyone who has a Harbor Freight 42976 Drill /Mill and is interested in the 3d solids model I'd gladly post the .dwg file to the downloads for them to download, if I can.

I currently have the x & y axis designed and built and having a great deal of fun playing with it. The very first thing I did was engrave some fancy script of my son's name using a pen and paper on the bed. Next I have to complete the Z axis design and build it.

While apart, I didn't like the mechanism they had to oil the table so I designed and built extensions for them. Now it is easy oil the table. The attached pictures show my method. It was amazing how much easier the table slides after proper oiling. It goes without saying guys, keep your machines well oiled.

Dead Nuts

[BobWarfield]

Very nice!

Can you show us any samples of parts made with it yet?

Best,

BW

[JRouche]

Hey Mr. Nuts, very nice conversion, real nice. JRouche

[wizard]

Nice conversion. Especially like the improvements to oiling. We made oiling impovements to some factory built CNC lathes a while back to very positive effect. Oiling should be on everybodies mind especially on a CNC conversion when you might not feel the lack of oil.

So what is the plan beyond 2 D CNC?

By the way thanks for the offer for prints, it is good to see the sharing.

Thanks
Dave

[Dead Nuts]

Yoy asked for some pictures of jobs cut with my mill. Actually there have been few as I am busy with other projects. However I have attached a couple of photos. One is a logo of my antique tractor club that I only tried on a scrap piece of acrylic and another of my wife's name also engraved into a scrap piece of acrylic. The I tried to include a photo of my screen to show the computer graphic of the only real job (a moon shaped piece of steel that limits the "float" on my son's tractor's hydraulic lift). It is made from 3/16" steel. It took about 1.5 hours as I don't know just how far I can push these stepper motors. The are NOT very powerful and the maximum speed I can get out of them is about 8 "/min with no load. Plenty for me, though as the table travel is only 4.5" x 9". So you can see I can go from min X to max X in just over a minute.

I am using Art Fenerty's "Mach 3" software to drive the machine. I am very impressed with it and especially with the level of support he offers.

[Dead Nuts]

Thanks for the kind words

[Dead Nuts]

Thanks Wizard for the kind words also. Yes, I have been a machinist for ofer 30 years and oil is VERY important!
Next, I am looking forward to attending the CNC workshop in Ill in a couple of weeks. Also I am looking forward to finishing the Z axis control.
Also in the last pictures above, I tried to take a shot of my monitor. Sorry it didn't turn out very well. I don't know how to eliminate the horisonal bar when taking a picture of a CRT, I afraid. However the parts fit into a mating part perfectly. It was great to see my own NC cut the parts!

[wizard]

Hi Mr Nuts;

Good to hear that all that experience is going to good use.

I'm very tempted by the CNC workshop, but am pulled in a number of different directions around here. I've heard some good things about it on the web, especially here. I know a little bit about custom CNC controlers and old Bandits but may be a bit short on PC CNC controls. Interestingly a small CNC mill or engraver has been on my mind for some time, so I really appreciate your efforts here.

Thanks
Dave

[Dead Nuts]

Dave

We also had bandit IV's where I worked. I am retired now and once you get CNC's in your blood it kinda festered there until you get something at home to "work" with.

It will be my first "cnc workshop" also, but Rick of RickOMatic fame, assured me I would have fun.

If you are not into controllers, look at Mach3 when you do get one. One of my concerns was the massive amount of electronics involved. With Mach3, a standard PC is your controller (the majority of the electronics). You only need stepper motors (or servos), and a breakout board. But that's all, not a lot of electronics to worry about.

Karl

[Docmani]

I just picked up one of these yesterday. Apparently this item is being discontinued and you can pick one up at your local Harbor Freight (if they still have one) for about $200. Thats not bad at all for the cash!

Are there any upgrades people have done for this model that have worked out well? A fine control on the z-axis would be something I'm interested in. I'm also curious about improving the x/y accuracy.

I'm looking forward to trying to convert this to CNC!

[RepairmanSki]

What did this machine originally sell for? I found a local shop that still has one but it's a floor model and his price is $250.

[Docmani]

It was originally around $400, from what I understand. Most of the stores near me were sold out.