chodges
06-17-2009, 06:42 PM
Maybe we have wrestling with the same issue too long to think clearly, but I just can’t get my head around this one …
We use our PRS Alpha in our sign shop, and we frequently make parts that will get stacked when assembled.
For some odd reason, there are discrepancies between identical cut-out parts, and the edges don’t line up on all 4 sides when we put them together - except in one orientation.
For example, I drew a 7” x 10” rectangle using Corel Draw. Then I copied this rectangle so I would have two – and I placed them side-by-side with a good space between them for the router bit to travel. These should be exactly the same when I cut them out – right?
Well, if I write the word “Top” on the same end of both pieces before I take them off the table, then stack them with the tops facing up and the tops on the same end, then all 4 edges are perfectly aligned.
The problem is that by the time these get sanded, painted, and moved about our shop, they are never kept in the correct orientation long enough to get to the point where they are glued together. If either end is rotated 90° and the short edges are flushed, then the long edges don’t match – one plate tapers away from the other from 0” at one corner to about 1/16” at the other corner. And if the faces where I wrote “Top” are not oriented the same, then the same error occurs.
Maybe I am trying to be too picky, but it takes a lot of time to sand stacked parts to make the edges flush on all 4 sides (we can’t change the orientation once the lettering has been added), and it just seems that we should be able to orient the top and bottom and face and back of a rectangle in any sequence and it should match another identical rectangle on all sides every time.
Here’s a sketch of what is happening …
8799
We have gone over our Shopbot extensively, trying to find something either loose or out of alignment. Everything looks ok.
Any ideas?
Thanks!
We use our PRS Alpha in our sign shop, and we frequently make parts that will get stacked when assembled.
For some odd reason, there are discrepancies between identical cut-out parts, and the edges don’t line up on all 4 sides when we put them together - except in one orientation.
For example, I drew a 7” x 10” rectangle using Corel Draw. Then I copied this rectangle so I would have two – and I placed them side-by-side with a good space between them for the router bit to travel. These should be exactly the same when I cut them out – right?
Well, if I write the word “Top” on the same end of both pieces before I take them off the table, then stack them with the tops facing up and the tops on the same end, then all 4 edges are perfectly aligned.
The problem is that by the time these get sanded, painted, and moved about our shop, they are never kept in the correct orientation long enough to get to the point where they are glued together. If either end is rotated 90° and the short edges are flushed, then the long edges don’t match – one plate tapers away from the other from 0” at one corner to about 1/16” at the other corner. And if the faces where I wrote “Top” are not oriented the same, then the same error occurs.
Maybe I am trying to be too picky, but it takes a lot of time to sand stacked parts to make the edges flush on all 4 sides (we can’t change the orientation once the lettering has been added), and it just seems that we should be able to orient the top and bottom and face and back of a rectangle in any sequence and it should match another identical rectangle on all sides every time.
Here’s a sketch of what is happening …
8799
We have gone over our Shopbot extensively, trying to find something either loose or out of alignment. Everything looks ok.
Any ideas?
Thanks!