hm 30 milling machine - about to possibly buy one

[domonic_cnc_guy]

i'm looking for advice on a particular machine the one below circled in red is the one


i've targeted it as it has the most powerfull motor, with the largest table and it's travel distances are perfect for what i want to do
the only downside is that it top speed is 2080 rpm which i'm not too concerned about since it is a belt style transmission and turning a new set of pulleys isn't exactly rocket sience (made a set of aluminium pulleys for a gmc drill press because the old plastic ones had had it)

i'm going up to the place thats selling them to have a good look on thrusday

initially i need it to mill out some cavities for form a two piece casing for some dataloggers i'm doing,

i'm curious has anyone had any experience with this particular one or similar

do they have any serious problems?
has it been reliable?
has anyone converted one of these to cnc? any problems?

anything i should know that the salesmen isn't telling me that i should know about before parting with the cash

[ataxy]

this will offer you good milling capacity as a manual mill they are not the perfect type for cnc conversion but they are cncable but you will be limited to quill movement for cncing as the roud column will loose its z position when lowered but as i said they are great for manual work if the z movement are limited

[bilinghm]

I have had one of these round column machines for over 25 years. It has some drawbacks, but the price, size and capability make it extremely valuable in my shop. I have had it completely apart, cleaned, honed, adjusted, repacked bearings, etc. My machine will make great parts.

I have improved it some: I "pinned" the rack allowing the head to index up and down with good repeatability, added an 180 DA collet system for fast tool changes, and I have installed a 3 phase 2 HP Leeson motor with a VFD for variable speed. These changes have made my old Enco a pleasure to use. This is the poor man's Bridgeport.

I plan on doing a smaller mill (X2 or maybe a taig) CNC conversion, but I couldn't do without the old beast. However, If I was buying my first machine, I would lean towards one of the big square column machines for all of the commonly dicussed advantages. These machines were unavailable when I was starting my shop.

Bill in Atlanta

[ataxy]

Originally Posted by bilinghm I have improved it some: I "pinned" the rack allowing the head to index up and down with good repeatability Bill in Atlanta

hey bill do you have any picture of your mod id like to see that and when you say good repeatabillity what kind do you get

[bilinghm]

Originally Posted by ataxy hey bill do you have any picture of your mod id like to see that and when you say good repeatabillity what kind do you get

Here are a couple of pictures. I tapped and bolted the rack at the top and bottom and put a roll pin in the center. I cannot give you a very good measure of repeatabilty except to sat that I can spot a hole with a center drill, raise the head up and put in a drill bit, lower the head and have it drop right back into the spotted hole. Its not perfect, but a huge improvement.

[ataxy]

Originally Posted by bilinghm Here are a couple of pictures. I tapped and bolted the rack at the top and bottom and put a roll pin in the center. I cannot give you a very good measure of repeatabilty except to sat that I can spot a hole with a center drill, raise the head up and put in a drill bit, lower the head and have it drop right back into the spotted hole. Its not perfect, but a huge improvement.

i am sure it does, i had tought ounce of bolting a linear slide to the side of one of those to see if it would help but since i bought a square column one instead the project was put back in the drawer

[domonic_cnc_guy]

thanks for the replies , any cnc conversion i'm concerned with will really only utilise the x and y axis's the most and at the moment it'll be for making holes in 16mmX100mm steel bar