Base construction for a PM-832t

[blue_luke]

Hello all!
I have been in and out of the hobby for the last couple of years but you will see me more active starting... now!
I just pressed my 'Visa nuclear button' today and placed an order with precision Matthews for a nice PM-833t: http://www.precisionmatthews.com/shop/pm-833t/

Taiwan made, better castings, better assembly, I think I will be happy with this one.
EXCEPT... the welded base for it is out of stock for the moment, so I've ordered it with just the 'chip pan' and plan to build my own base.

I already own a PM25 that I got about 3 years ago with the optional welded base. I never really liked this machine, especially the base. Now I am far from bashing the machine, it is a good machine but i've made a wrong choice. So it is my mistake and please do not take this statement as of a criticism, I screw up in ordering this machine, that's all!
But one of the thing I don't like about it is I find tha base a bit flimsy, definitely not with a large enough base foot print to make me feel comfortable... So I mounted it on heavy steel rectangle tubing, 2 X 4 X 1/4 "thick walls where I placed levelling hockey pucks. This works nice but I am still not completely satisfied.
Again, nothing wrong with the machine, I bought a small chevy when what I needed was a bigger and nicer car!

So here is (finally!) my question: how should I build a base for it?
- what should be a good foot print?
- How much weight should I look for?
- should I fill it with concrete?
- Should I add stiffening members to the column?

I am open to any suggestion, advises, crazy idea etc....

Thanks, Luc

 

[Wreck™Wreck]

Concrete foundation, then a granite plate that has been scraped "dead flat" on top of that. Afterwards a cast iron plate also scraped flat to within .0001" on both sides. Mount the mill on these substrates you can't go wrong with this method.
I may have missed several steps but am sure someone will correct me in due time.

 

[wrmiller]

I suggest that before you start planning mods to the mill, you may want to get it set up and try it first.

My 9x40 bench mill weighed a bit more than your 833 and it sat on a stand made of 2x2" thick walled tubing with cross runners where the machine bolted to the stand. The stand was about 3' square with the machine mounted such that the Y-axis handwheel hung over the front for access. This actually put the heaviest part of the machine more towards the middle of the stand, instead of towards the rear.

The stand had heavy duty wheels and metal leveling feet installed so I could move it around my garage/shop and then get it up off the wheels with the leveling feet. Worked well too, except that caution was required when I started wheeling around almost 1100 lbs. of machine around. Once started he kept trying to go in the direction he wanted, instead of the one I wanted.

 

[blue_luke]

I see! Actually the idea of spreading the bulk of the weight over the center portion of the stand, which as you mentionned is more toward the rear of the machine, is excellent! I will keep this in mind as I design the base for it. To me levelling feet are mandatory, but wheels not as much. I am too thinking of building a sturdy base made of thick walled 2X4 and 2X2 square steel tubing as you did, and would include a case of drawers in the base maybe? I am also considering filling the base with concrete... maybe this is a tad overboard?
Luc

 

[ConValSam]

Welcome Luc

I'll leave the specifics to our better skilled fabricators, but I would add as much horizontal space beyond the machine base as practical; you can never have enogh bench space in shop and a machine table always ends up with every tool from the current project and the last five laying about.

At least with "bench" space around the mill you can shove it out of the way and not onto the floor!

 

[blue_luke]

"I would add as much horizontal space beyond the machine base as practical"
Actually NO! I found that most of us are like a gas.... and as such we tend to fill all the avilable space!

I found that the less bench tops, tables etc I have, the less clutter there will be in my new small shop (basement room, 10'X13')
On the other hand, there is never enough drawers, shelves and racks and anything that has not a place on a shelf will end up on the floor and piles there!

But we disgress....

 

[blue_luke]

Hello all!

I just received confirmation from Nicole at Precison Matthews that my machine is shipping this afternoon!

It should arrive around Wednesdy or thursday, mother nature permiting. (we received 200 feet of snow last week end and it is now 3000 degrees below zero!)
Yeee! .... and YIKKES!!
- my little shop is not ready!
- I have no base for it!
- The electricals (240Vac) are not done yet!

But these are exciting problems to solve!
I have it shipped where I work where we have fork lifts, overhead crane etc... I will dismantle it in chunks to move it to my basement and 'remantle' it in situ.

So for the base I am ordering the material tomorrow and will start fabrication in earnest.
I gathered many ideas from here, from some youtube VDO's and I think I came up with what looks like a good match plan. I will keep you posted but I decided on a few points...

- The base will be all welded square thick wall tubing (2X2 and 2X4 for the footing)
- there is a provision for adjustable feet mounted on hockey pucks (Yes I'm Canadian! )
- to set the level I am foresighting a '3 points' system where once the level of the machine is established, the leveling system will become a 4 points system for stability. It is realy a 5 points system finally after all....
- If needed, the base can be filled with concrete to add to the mass, I hope not because this make a realy nice niche to install drawers!
- I also envision a vertical triangular reinforcement from the base to the pilar at the back to help stabilyse and damp vibrations. More to come on this subject
- At more than 1,000 lbs with base, this guy will rest where I set it!

I will keep you posted about my fabrication and the results of the system I envision, which I think will take care of at least lateral vibration of the pilar.
We'll see....

Sincerely, Luc