True Flat Probe Stylus

[Scott D. Haselden]

Has anyone ever seen a probe stylus that had a true flat edge on it? I am trying to measure a point on a fan blade that is angled on a rounded edge. So basically, the edge of the fan blade is rounded, and we shave the diameter off to a point that it comes to a sharp point. I have to measure the dimension where that point sits down to the flat plate in the middle. Essentially, the "H" dimension shown in the attachment. I was able to get this dimension with height stand, using a blade, but I have never seen anything like this for CMM, and they specifically require cmm measurement. Ordinarily, we use a 2x20 shank probe to measure fans, but they also ordinarily have a radial measurement point. These fans do not. Anyone know of anything, or any where I could obtain a stylus that would work like a flat blade? I tried a disk probe, but the calibration off those is to the little nub on bottom, so the numbers were way off.

Anyone else have an idea of what I can use? At this point I am desperate enough to try anything, or maybe even buy anything.

[Douglas]

Disc probes are spherical, like a ball with the top and bottom removed.

You are talking about a cylinder styli that has the shape of a plain cylinder.

[Sora5]

We use a custom disc probe that has a flat wall instead of a radius wall. Get ours from QMARK. Custom made. Not cheap.

You'll have to modify the probe data file to add in the components to be able to build it in pcdmis and then be extremely specific with your usage as having a flat wall on the contact surface will make it very dependent on how the part is fixtured in relation to the probe head.

[RIDER]

Scott D. Haselden Renishaw has a variety of datum styli. Not sure whether or not this is what you want but here's the link

https://www.renishaw.com/Shop/Default/Home/Styli/Datum

[DAN_M]

I have never seen square probes like this. In what circumstance would you want to use one?

[Scott D. Haselden]

Thanks guys.

I found a workable solution from Renishaw, and had the probe overnighted yesterday. It turns out that a standard 3mm stainless steel barrel probe had a true flat bottom that is perpendicular to the barrel. According to the specialty guys at Renishaw, this will give me a true dimension in Z axis, as long as I stay away from the radiused edges. basically, I will have a 2.5mm workable surface, but that will do for my application. Since this will be a single measurement strand, I will have the DCC drive the probe to location, then drop back into manual mode and manually take the hit, in order to make sure I hit on the flat surface, and avoid the radiused edges. Not the most efficient method, and definitely not a workable solution for possible production needs, but will get us through this crisis.

For anyone that may have this problem in the future, the barrel probe catalog number from Renishaw is: M2 Ø3 mm silver steel cylinder, L 12.75 mm Product code: A-5004-7590

[Scott D. Haselden]

OK, So this is aggravating. I go to build the probe up, and can't find the standard tip anywhere in the probe utilities dialogue, and can't find where to customize a probe tip. Anyone have any ideas?

[louisd]

hit F1 and look up "PROBE.dat" or "custom probe builder". the help file is pretty well worded.