I am converting a PM-833TV to CNC. I have heard that since this mill has a one shot oil system, that it leaks lots of oil on to the bench. I am building a flat bottom enclosure (I do not plan on using flood coolant) and am questioning if I need to use the steel chip pan under the machine. While a pan under the machine will catch oil leaking from the mill, it means cleaning chips from both the steel pan as well as the enclosure. It would be easier to scoop up chips if I don’t use a pan. In essence the bottom of the enclosure would act as a large pan. Do you find that this mill leaks lots of oil? Do you think I can nix the chip pan? The images show the welded base with a wooded top. I plan on laminating the top with gloss white Formica and building an enclosure on top of the Formica base.
if you run a mist coolant system that will drain into the steel pan you have as well most likely. so it might not be a bad idea to have a drain line on the pan and have the drain run to a 5 gallon bucket or some kind collection point under the table to make it easy to deal with. the chips probably wont hurt the wooden table much but if the mist fluid run off and oil hit the table the wood is probably not going to hold up very long. you really need some kid of chip containment solution over all or you will be doing a lot of cleaning up every time you run the machine. chips pretty much go all over the place when you are machining. So a lot depends on how much use you think the machine will see? The size of parts you will be making will factor into this as well.
the pan with wood sides to contain everything should work ok to start with until you see exactly what your up against. windows so you can prove new stuff out and watch it close. i would fit that into the design too.
Thanks Jay. I appreciate your thoughts. I was not aware that if you run mist coolant (I plan on using a Fogbuster) that you end up with an appreciable amount of liquid.
if you end up doing a 3D tool path that is running for a long time or have a large part that takes a while to do you end up with a lot of the liquid running off the machine. if you empty the mist coolant tank running something like this it’s pretty much like dumping the tank on the part and letting it run off the machine ending up somewhere. mist will keep it localized to the work holding area so it ends up in the catch pan at least. flood coolant would end up all over the place and require a fairly watertight enclosure. the catch pan is a very good add on IMO.
The issue isn’t the one shot oiler per se, it’s the fact that the manifold lines go into drilled holes not oil fittings. That being said, I can’t really blame them. When I had mine apart installing the ball screws I looked at tapping and installing oil fittings instead and I couldn’t see a way to make it work given the size limitations of the casting.
Pig mats and shop rags.
Thanks for your thoughts! Funny, I watched a few videos of folks tapping and installing fittings as you noted, but questioned if it was feasible (I have not disassembled the mill yet). I had a second idea of cleaning off the current fittings and applying silicon calk around them to minimize leaking. Not sure if this will actually work.
Just curious, when you did your conversion, did you have many issues with the parts from the Heavy Metal kit fitting properly?
one other thing you might want to consider is adding check valves if they are not in the original set up. when you pump oil it is going to follow the path of least resistance and with out check valves you could end up with oil points that get no oil to them. something i have to sort out myself with my project but the original machine had them in the system. leaks are bad but lack of flow control is also bad.
Thanks Jay. I have been resourcing banjo fittings just for this.
All the best… Richard
if you go with brass fitting and get into compression fittings copper refrigeration line is a cheap option for custom lines. i don’t see why you could not use plastic push to connect either. i am pretty sure check vales can be had for that route as well. i’m not sure which way is cheaper? but oil lines are low pressure so the push to connect lines should have no trouble in the pressure department and if air does not leak i doubt oil would leak using that type of line. i actually think that is the route i will have to go since half of my oil points are moving with the saddle of the machine. being able to flex and move solves the problems in that area.
with the conversion i am working on the check valves were placed at each branch in the oil circuit on the original machine. since i have more points to oil i will need a few more check valves but those video’s are a good starting point for reference especially if your doing the same kind of machine.
i have my doubts i will ever find any information on how to run oil lines on a 1977 DoAll surface grinder converted into a CNC horizonal mill best i can do is look at what is out there and apply the concept and modify it to my application i don’t have the manual oiler. the one i got actually has some control on the duration and how often you want it to run for. it’s actually powered and programable to control how much oil you want pumping. it even has a float in the tank and alarms when then oil level in the tank is low. but i am glad to see my thought seems to have been proven with the push to connect air lines in those video’s.
Everything fit except the z ballscrew bearing cap at the top of the column. The holes in the cap that were supposed to fit the same holes for the bearing cap for the original acme screw we’re different. I hat to use a small milling bit in my drill press to make slots in it to make it work.
Sorry for the delay responding. I didn’t get an email notification (or missed it)