stand for mill-drill machine

ARC-170

Jeff L.
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I wasn't sure where to post this, but since it concerns a Rong Fu or clone mill, I thought I would put it here. I'm looking for a Rong Fu clone and some of them come with a stand and some do not.

I have 2 options:

WOOD
I thought of making one out of wood, but wanted to see what others thought. These are really heavy; I've seen weights of 750#. I sketched a design I'd like some feedback on:
mill stand wood.jpg
It consists of 4 (3 are shown) 4x4's with 1/2" plywood as bracing. The plywood goes on all 6 sides. It is attached with 3/16" x 2" long lag bolts (5-6 on each side of each panel. Only 6 on one side are shown). I thought the 4x4's were strong enough to hold the weight, especially when on end, and the plywood takes care of any shear forces.

It would cost anywhere from $75 to $115, depending on whether I used 1/2" or 3/4" plywood.

Has anyone ever put one of these on a wood structure? Got any photos you could share?

METAL
The other option is to buy or make a metal one. I've looked online, but the maximum weight of the ones I've found is 660#. Has anyone ever had a welder make one? How much are they and what did they look like?

Thanks!
 
I have the Rong Fu sheet metal stand, and am afraid I'd have to pay somebody to take it off my hands. I'm in a small space while waiting on my dream shop to be built, so I don't have the space to build a replacement for now, but believe me, it's on my list. If you look at RF mills, do not consider the factory stand as "value added" on your purchase.

There are two or three superb build threads on this site for RF mill stands. It would probably be worth it to you to scroll through the RF subforum and see what's there.
 
Here's a metal design:
mill stand metal.jpg

It uses 1/8" thick, 2x2 angle iron (steel) that is bolted together with 3/8" bolts. I'm not sure how this will hold up to shear and twist, though. I've built stuff before like this, but it didn't hold a 750# milling machine.
 
I have the Rong Fu sheet metal stand, and am afraid I'd have to pay somebody to take it off my hands. I'm in a small space while waiting on my dream shop to be built, so I don't have the space to build a replacement for now, but believe me, it's on my list. If you look at RF mills, do not consider the factory stand as "value added" on your purchase.

There are two or three superb build threads on this site for RF mill stands. It would probably be worth it to you to scroll through the RF subforum and see what's there.

That bad, huh? I'll look at the threads, thanks.
 
If making out of wood like your drawing I would not use lag screws. Lag screws aren't really made for that type attachment. 1 1/2 flathead wood deck screws would be better. You also don't want the screws in a straight line. That can create a zipper effect. I would stagger the screws 4" on center alternating from one side of the post to the other.

The bigger question is how do you plan to attach the mill/drill to the stand? Again I would not use lag screws into the tops of the posts. My guess is that you plan to use typical construction 4x4 from you local lowes or home depot. Bolts typically don't hold very well when screwed into end grain of softwood. One solution is to drill the holes over size and wobble the drill around to create an uneven hole. Then saturate the hole with epoxy slightly thickened with cabosil and put the bolt into the hole. Be sure to use mold release wax on the bolt or you will never get it out. Once the epoxy has gone off but not yet fully cured remove the bolt. Once fully cured you will have a threaded hole to screw bolt into.

I would not put plywood on the bottom. It doesn't really add anything to the structure of the stand. You could leave off the front and put shelves or drawers to hold stuff.
 
If making out of wood like your drawing I would not use lag screws. Lag screws aren't really made for that type attachment. 1 1/2 flathead wood deck screws would be better. You also don't want the screws in a straight line. That can create a zipper effect. I would stagger the screws 4" on center alternating from one side of the post to the other.

The bigger question is how do you plan to attach the mill/drill to the stand? Again I would not use lag screws into the tops of the posts. My guess is that you plan to use typical construction 4x4 from you local lowes or home depot. Bolts typically don't hold very well when screwed into end grain of softwood. One solution is to drill the holes over size and wobble the drill around to create an uneven hole. Then saturate the hole with epoxy slightly thickened with cabosil and put the bolt into the hole. Be sure to use mold release wax on the bolt or you will never get it out. Once the epoxy has gone off but not yet fully cured remove the bolt. Once fully cured you will have a threaded hole to screw bolt into.

I would not put plywood on the bottom. It doesn't really add anything to the structure of the stand. You could leave off the front and put shelves or drawers to hold stuff.

You make good points, thanks. I wasn't sure about the bottom piece; I'll probably leave it out. I thought it might help with torsional force. I don't have a mill yet so I don't know where the holes are for attaching it. I was not going to lay bolt it into end-grain, though. I thought maybe I'd use inserts and screw bolts into those. I don't think there are inserts big enough, though.
I thought about drawers but I also want shear strength. I'll have to make a more detailed design.
At this point I just wanted to see if a wood stand would even be feasible.
 
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