Time for some advice on brakes

[gtzero]

Hi All,

I heard a little squeal from my brakes the other day. And there was no rain in sight. So it sounds like it's time for a brake job. I had Gil upgrade my brakes years ago when he built my car. And he seems to remember the front rotors are from Straus. And since they are cross-drilled, they can't be turned. Anyone know about this brand and where I can source a new pair? I'm running the BMW 320i calipers.

Since I have 16 inch rims up front, I'd be interested in hearing of other possibilities such as a Wilwood or StopTech or Brembo upgrade.

Thanks for any help,

Manny

[GTJIM]

The cross drilled holes do present a problem for turning as the tool tip will "bounce" over each hole leaving a wave pattern behind.
However the discs can be 'Blanchard ground' which is a grinding process rather than a turning process. A brake reconditioning - not a drive in and we fix 'em quickie shop! - machine shop should know how to do this. It is commonly done on flywheels to so that the hard spots can be smoothly machined. So a Clutch and Brake Jobbing shop should know the term.
This presuposes that the discs you have are not worn below the minimum thickness.

[namba209]

Jim, I remember the old magnetic tables used for surface grinding flywheels, but I found out they are a thing of the past when I had my V-6 manifold flanges trued out for flatness. At least the automotive machine shops here don't have them anymore, it's all CNC now. There are no more watch repairman now, we've become a throw-away society. End of social comment.

[nobody]

No Ron it's just more precise. You touch off the grinding wheel to the rotor and press M+Z,on the tools page to set your Z plane. type in Go3 x dimension y dimension for center point with a R value (radius) Don't forget your F value (feed rate). you need do a t (tool) call if you want to alter it's path for a second pass. Don't forget the M3 M8 and M5 M9. On a blanchard it's best to do a go4 M4 z- for a final cut.

Not that tool path programming is engrained in my brain or anything.

I'd have to look up the G code for a repeated cycle.

CNC is easy

[namba209]

That may work for a flywheel, Dave, but on my exhaust manifold flanges they had to true them out by holding them by hand on a moving abrasive belt. Talk about old school. If they would have had a magnetic table and a water cooled disc it would have taken about 5-10 minutes per flange and not cost almost $100 for the pair. They did the same trick when I took the completed manifolds in after welding, but only charged me half because they had something to hold on to on the belt. And they had a whole room full of CNC machines but nothing that would work on the manifolds or flanges. Go figure.

[nobody]

I do the same thing here for intakes and exhaust flanges. Mine is wide enough to do carb bases that have gotten warped. Neat trick to try if your rebuilding a carb. The platen behind the belt has to be dead flat tho.