Does anyone else here re-cut their valve lash shims? I made a jig to do this with an old timing belt tensioner, an old lifter, a magnet to hold the shim in the lifter and some steal plate. Then I square it up to my bench grinder. Cuts real flat and square. Anyone else tried anything like this, or do ya just pay the $12 bucks a shim?
Has anyone had any issues doing this?

 

I had an engine rebuilder tell me you can't do this, because the shims are domed. But a little work with a micrometer showed that all my shims are the same thickness at every point.

I would be concerned that the shims are case-hardened; grinding more than .04-.08mm could remove the hardened surface. But I don't know if that is the case.

The shims are designed to rotate (to even out the wear), so you would need them to be ground real flat and square. A surface-grinder is the tool to do that, but not many people have one of those in their garage! I have heard (on this forum) of the occasional owner using a surface grinder.

Do you use a micrometer to check the uniformity of thickness?

 

I have been cutting these for a while on an old test engine I planned to change out at 50k miles. This was to test things like this out this out. I measure them with a micrometer and chack them with a straight edge to make sure they are all square and uniform. I only cut the bottoms so the hardening is not damaged and if you check the bottoms of a stock shim you will see these are cut flat and are not concave.
I have not seen any adverse effects after 50k, but these things don't wear very fast. The ones I have done seem to rotate fine and wear evenly. In the past I cut them by hand, but I am interested to see how they come out cutting them with this jig . They should be much better cuts and I am using a finer wheel, but this is a new engine not a test engine like before so I am hesitant.
Toyota used to trade shims for free, but then the manager decided it would be better customer relations to charge $14 dollars each for used shims. That's when I started cutting them again. When you do a lot of these it can get expensive especially if you have a 3.4 to do. The good thing is I can get perfect clearances. I have found that if you get one that is a little out of square then they clack a lot and really loud, so you know to change it right away. Any irregularity in the valve train makes noise on the 3.0. We will see shortly how it works out. I don't have time to run tests until I get my short block done. I have run into issues using the Total seal rings. It's not the rings that are a problem it's seems to be the machine shops work quality. I will update soon.