If the edge of the table is not parallel to the direction of travel which seems to be what you are saying here, it is not anything to do with the slide way strip that you have shown in the photo with the caliper reading of 2.973" .The guide strip that is screwed to the underside of the table the one the gib strip runs on controls the position of the table ,you would need to check that the guiding edges of this strip are in line with table edge.

In any event apart from from a nuisance does not affect the operation of the machine in any way ,for what it is worth you would probably need to replace the strip rather than try to reposition the countersunk holes any distortion to the existing strip is likely to lead to more problems.

John

It would be a help if the pictures were zoomed out a bit. Otherwise it's difficult to see what is being measured. It's not essential that the sides of the table are parallel to the ways, but it's an all round PITA if they're not as then they cannot be used as reference surfaces.

Andrew

The two ground surfaces should be running against each other.

But, the Ground face fixed to the table should ensure that the table moves in a plane, X axis, left to right, perpendicular to the Y axis, to and from the operator.

It seems that you are likely to to be in a situation which is the reverse of the way that things are normally done,, by needing to align the ground face of the strip so that it is parallel to the Tee slots

I would suggest removing both strips and fitting to ground strip,(but not yet dowelling it ) so that it rides against the ground face on the bed of the machine. Adjust the table relative to the strip, until the T slots clock true. A copper/hide mallet is going to be useful for this.

When the strip is aligned drill and dowel / rollpin to maintain that alignment.. This may mean that new holes have to be drilled, countersunk, and tapped at new points along the strip.

Once you have achieved that condition, the problem of the 0.027" variation can be addressed and correcte on the other strip, in similar manner.

(You need the Tee slots to be in the same plane as the motion of the table, or will always have to clock the vice to set the jaws parallel to the line of the cut. Once the T slots and line of travel are the same, the vice can be aligned to the table with keys, or an alignment fixture ).

Howard

Posted by Steve 355 27/10/2021 10:34:11

Is this statement true? :- It doesn’t matter if the milling table is not square to
the base of the mill (within reason). The milling cutter is round. What matters
is that the X, Y and Z axes run perpendicular. Tramming ensures the Z axis
is perpendicular. The X and Y axis should be perpendicular by
manufacture of the table.

Yes it is true , except for the last part after i had built my Dore westbury
the squareness of the X and Y was off by few thousanth's of an inch,
it is possible to re-machine the Dore westbury XY cross slide on a Myford 7
lathe cross slide because this is how i corrected mine.

There is little point to having the tee slots in line with the travel of the table
because of, 1 the longitudinal slots at each end are too short in all probability
to be able to mount any additional accessories (vice) without using some of the
other slots in either side of the table ,2 the tee slots in a Dore westbury are cast
in and not machined and are useless as a reference unless reworked
for that purpose.

As it is the 1st photo that you have posted showing the underside of the
table the dowels are in the correct slideway/ guide ,as you have surmised the table
has been fitted the wrong way round, however fitting the table as in the last photo
which is the correct way round also puts the guiding slide with the dowels on the
correct side, it is worth noting that if you remove either of the 2 guide strips from the
underside of the table they may be shimmed as this is the normal method on these
machines to control the table lift /clearance.

John

Edited By John P on 27/10/2021 13:35:41

Steve,

Try attaching the bearing for the leadscrew with one or two setscrews, Hopefully after a number of combinations the tapping that is out of position will be obvious.

You then have a choice.of solutions, depending on how far out the hole is.

1. Open up the hole to clearance around the odd man out.

2 Using the bearing block as a jig, drill a jig, but with the rogue hole only drilled to thread size (Probably 1/4 BSF )

Open up the hole to tapping size for 3/8 BSF, 8,25 mm&nbsp

Using the jig to drill the rogue hole out to 8.25 mm and tap 3/8 BSF.

Turn up a bush with a 3/8 BSF external thread, and an internal thread (Presumed to be 1/4 BSF)

Screw the bush into the hole, ensuring that it not above flush. Use thread locker if you wish.

When the anaerobic has cured, reassemble, and hopefully table movement should be as wanted.

Howard

Posted by Steve 355 27/10/2021 14:07:24

Now I’ve just got to work out how to drill accurate holes in the end of that table.

Luckily I have a big pillar drill!

The easiest way to do this is to remove the XY slide from the machine,
lay the table upside down on a bench fit the X leadscrew nut in position
on the XY slide fit the XY slide on the table fit and adjust the gib in place ,
screw in the leadscrew and end bracket as far in towards the nut as it
will go ,if you view down alongside the table the leadscrew should be
visable and it will be easy to see if the leadscrew is parallel with the
slideways then looking down from the top likewise the leadscrew
will be in line with the slide bars.
Probably easiest to just fix the end bracket to the table with a dab of epoxy
glue let it set ,make up a long centre punch that fits in the holes of
the end bracket ,if the glue will hold you can carefully traverse the
XY slide along the table before marking the 2 hole positions to test
the position.
When satisfied with the positioning use the punch to mark the
hole positions drill and tap for the 1/4 bsw fixing screws if they are
still this size they are on mine.

John

Under one end or both?

Not knowing the DW, but looking at your photographs, it may be that there is excess clearance between the steel strips on the bed and the steel strip on the underside of the table.

If this is not adjustable, it might be worth measuring the clearance at each end and side and then carefully scraping the surface of the bed on which the steel strip sits to reduce the clearance.

If this is the case, lots of bluing, scraping and offering up seems to loom!

Obviously, there has to be some clearance for the table to move, it just needs to be minimised.

HTH

Howard

.

The lug shown in the photo ,the only function of this is to provide enough
material for one of the tapped holes that hold the lead screw nut,
the two places marked on your photo here are the only adjustment
for the vertical clearance of the table if you remove those strips
there will most probably be some shim material between the
strips and the table ,there should be some reference to this in the build notes
that i believe that you have.

John