Need Help!- something is not quite right

[Drools]

I need some advise on a problem I'm having. I have made several of these clocks from plexi. See pictures below.
I route the roman numerals first then the center hole and the 2 x 1/8" alignment holes, lastly I cut the clock out. I then flip the clock and insert 2 1/8" dowels to align the clock for cutting the pocket.
My problem is the pocket is not centered. There should be .33" on both sides of the center hole but after cutting the pocket I have .368" on the right and .308" on the left of the center hole. I have done 4 of them and each is the same. Is this backlash? Maybe the Xaxis is "insert your opinion here"
The distance top and bottom of center is right on which is the Yaxis.

Thanks for the help guys.
I want to get this fixed before I move onto other items that require double sided routing.

[ger21]

Are you sure the dowel holes are in the correct place?
And is the fixture you're doweling to?

[Drools]

Hi Gerry, I drilled the alignment holes through the plexi and into the scratch board. I think they are in the correct spot.

[ger21]

measure the distance from each dowel hole to the center along the X axis.

The two angles look different, so I'm guessing the holes aren't equally spaced from the center.

[Drools]

I added the dimensions that you asked for, just refresh the page.

[Drools]

I attached the dxf

[ger21]

You need to verify that the g-code is correct and in the proper relation to your fixture holes.

[Drools]

ok. thanks for the help. I will get on that.

[RomanLini]

There should be .33" on both sides of the center hole but after cutting the pocket I have .368" on the right and .308" on the left of the center hole.

The only possible cause of that is that the 2 dowels are not equally spaced from the centre hole, as Ger21 said.

Fortunately since you know the error is;
(0.368 - 0.308) / 2
so the error is 0.030" all you really need to do is move the pocket over in your CAD file (move it 0.030") to suit the fixture, ie you don't need to make a new fixture.

[Drools]

I looked at the date and time on the gcode files and iirc I had to slightly increase the outside diameter of the pocket and decrease the inside diameter to fit the HD platters I found. So the gcode code for that part is slightly older than the rest of the files.
I will parse through the code but I'm no expert at reading gcode.

[cliffy]

Hi Drools,
I think your X and Y are not at right angles to each other,
if it’s out by just a little you won’t see it in your clock, but as soon as you flip it over the angle problem will be doubled, and now you can see it.

[Drools]

That is quite possible cliffy, thank you for the responce.
A quick question, would this only effect the X direction?
My measurements on the Yaxis cuts are perfect.