Base

I decided to make the base large enough to allow a 12" x 24" cutting area.

The base frame consists of the following components:

  • 2, 8020 10 series 2040 x 36" long
  • 2, 8020 10 series 2040 x 18.25" long
  • 8, 2" corner braces with gussits

The exact lengths of each piece of extrusion can be a little off as long as the two apposing sides are equal.  IE the two sides can be 36.125 long and the two ends can be 18.3".

If they are the same size and the cuts are square, you can pretty much garantee the frame will be square.

The frame is held together with two 2" corner braces in each corner as shown here.

Note how the upper brace is mounted in the second slot.  This allows some room to add a set of cleats later to hold our removable slats for a plasma cutter, or a drop-in table.

It is important that when assembling the frame that it resting on a flat surface.

You want all four pieces to be perfectly flush on the top and bottom.

 

Stand

The size and weight of the any machine configuration make it more prudent to use a dedicated stand. All the machine configurations can use just about any stand that will support the overall size of the frame (22.25" x 36").

However, the plasma cutter will need an open frame so a down draft or water table can be added.

For this reason I decided to build my own stand using some heavy duty steel workbench legs and some slotted angle, as shown here.

The legs can be found here:

Edsal 5709 Heavy Duty Workbench Legs

The steel can be found at most home centers. 1-1/2" slotted steel angle works well. Just make sure its 36" long and 14Ga thick.

 

Stand Assembly

The two leg sets are attached to each other using a piece of slotted angle.  Two 1/4" bolts are used on each end of the slotted angle as shown here.

It is important that the stand be assembled on a level surface. This will allow you to use levels to insure the legs are propperly leveled.

With all the bolts attached and holding the legs in place, I snugged up all the bolts on one end.  I then used a level to make sure each leg was straigt, as I tightened the bolts.  I then moved to the other end and did the same.

If you are going to add casters to your build, now is the time to do that. 

I recommend double locking casters, but keep in mind, any kind of caster will make the machine a little less rigid.

 

Mounting the Base to the Stand

Once the base is mounted on the stand, I found it much easier to work on the CNC. 

 

I started by placing the base on top of the stand.  I centered it by measuring on both sides of base to the edge of the upper leg support.  In my case it was 3-5/8" from each edge.

I had a little over 1/4" hang over on the front and rear.  It was not quite square but this does not matter as long as you have it centered over the stand.

With the base centered make a mark at the center of the outer most slot, as shown here.

This is done on all four corners.

I then used a square to extend the mark along the top of the upper leg support.

I drilled a 3/8" roughly in the center as shown here.

Each corner is raised and a 1/4" carriage bolt added to the slot as shown here.

I slipped the bolts through the holes I drilled previously and added a washer, lock washer, and nut.

I found that the base would rock, because it was not setting flat on the stand.  This is due to the fact that the legs are welded to the braces, and probably warped a little.

To easily solve the problem, I just inserted a shim under one of the high ends and tightened the bolts.

 

I used a small piece of melimine coated particle board to test if the top of the CNC was flat. 

If it is not the particle board will rock on two of the corners. This is a sure sign that you need to go back and shim the base.

Once the base is mounted on the stand, I found it much easier to work on the CNC.

I even added some temporary shelving to hold parts during the build.

 

Note that it is my intention to use this base and stand as the main platform for all my CNC Construction Set builds. But only time will tell as I put the machines to use.