520 Rip Fence

BigSky · Post by **BigSky** » Thu Nov 26, 2009 7:46 am

I hope that someone can help me to determine if my rip fence is deformed and how to fix it..

This is not the rip fence that came with my upgrade but it is very disappointing.
When I move a dial indicator along one side it seems reasonably true. The indicator varies from one end to the other by about .005" give or take. But when I check the other side it deviates about .012" and the readings get lower in the center and then go back up at the other end. What could cause this and how can it be fixed. It does not appear to have been dropped and if it was bent one side would not be true. I am confused. The deviations are not huge but are puzzling none the less.

dusty · Post by **dusty** » Thu Nov 26, 2009 11:54 am

BigSky wrote:I hope that someone can help me to determine if my rip fence is deformed and how to fix it..

This is not the rip fence that came with my upgrade but it is very disappointing.
When I move a dial indicator along one side it seems reasonably true. The indicator varies from one end to the other by about .005" give or take. But when I check the other side it deviates about .012" and the readings get lower in the center and then go back up at the other end. What could cause this and how can it be fixed. It does not appear to have been dropped and if it was bent one side would not be true. I am confused. The deviations are not huge but are puzzling none the less.

I seriously doubt that it is bent but the face could have gotten damaged somehow.

If it were bent, one side should be the inverse of the other.

That being the case, all I know to do is build a pseudo fence to give you the straight surface. Problem will be the weight. That fence is heavy without anything tacked on.

JPG · Post by **JPG** » Thu Nov 26, 2009 12:24 pm

dusty wrote:I seriously doubt that it is bent but the face could have gotten damaged somehow.

If it were bent, one side should be the inverse of the other.

That being the case, all I know to do is build a pseudo fence to give you the straight surface. Problem will be the weight. That fence is heavy without anything tacked on.

I have not had one of these in my hands, but I assume it is an extrusion with a 'hollow' interior. If so it is probably 'warped'.

Unless 'getting inside it' is possible, Dusty's suggestion might be the best ya can do!

charlese · Post by **charlese** » Thu Nov 26, 2009 2:47 pm

MarkV - Sounds to me that there has been a sacrificial fence attached to the fence and tightened enough to stretch the aluminum. My 510 fence has a bow (inward) in the center of a few thousandths. Still works alright!

The best advice I can give is to rip a couple of boards, then check to see if the results are straight and like you need. If so, put the dial indicator back in the drawer, until you need to check something again.

Another sacrificial fence, maybe one on each side might be your solution.

dusty · Post by **dusty** » Thu Nov 26, 2009 6:02 pm

charlese wrote:MarkV - Sounds to me that there has been a sacrificial fence attached to the fence and tightened enough to stretch the aluminum. My 510 fence has a bow (inward) in the center of a few thousandths. Still works alright!

The best advice I can give is to rip a couple of boards, then check to see if the results are straight and like you need. If so, put the dial indicator back in the drawer, until you need to check something again.

Another sacrificial fence, maybe one on each side might be your solution.

Nice try Charlese but I threw the box for the dial indicator away. That puppy stays ready for a call to duty on a moments notice.

charlese · Post by **charlese** » Thu Nov 26, 2009 9:37 pm

dusty wrote:Nice try Charlese but I threw the box for the dial indicator away. That puppy stays ready for a call to duty on a moments notice.

O.K.! On call for emergency micro measurements!

That's a good thing if it fits your needs. However I suggested a drawer - not the box!

HAPPY THANKSGIVING!

dusty · Post by **dusty** » Fri Nov 27, 2009 6:08 am

As charlese suggested, attach new "sacrificial" sides to the rip fence. If the rip fence is really bad, you may have to shim these sides to get them true to the table and parallel to the blade. It might be a lot of work up front but the effort will save your rip fence.

I've seen some done for Beismeyer fences that are like this but have a piece on the top as well. In other words, the sacrificial encases the rip fence on top and both sides.