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Fluke TL71 Probe mod

eKretz

Apr 8, 2013
251
Joined
Apr 8, 2013
Messages
251
I thought some of the guys here might be interested in my latest project. I've sharpened up my 87V's probe tips a few times now but they rapidly dull again, so I decided to change them to tungsten carbide tips.

I grabbed a couple replacement points for General brand carbide-tipped scribers (part number 88P) and chucked them in a drill, then ground the steel part of the shank down to the same diameter as the carbide points (in this case about .042") for a length of about ¼" from the point, then cut the tips off so I was left with small cylindrical carbide tipped steel rods of .042" diameter x ¼" length.

Next I flattened the points on the ends of the stock Fluke TL71 probes and center punched them as close to center as possible with magnification. I used a small toolmakers clamp to clamp the probe square to the flat surface of the clamp, then drilled .045" holes down into the probe tips to the proper depth on a drill press - with the probe handles extending through a hole in the table.

Last, I fluxed the tungsten-carbide tips and the probe tips with Stay-Silv silver soldering flux, assembled them, and placed the probe body into a container of water so that the probe handles were submerged about 1/8" in the water and then silver soldered the tips in with a MAPP torch.

Following that, I sharpened the tips with diamond hones until they were good and sharp. The following images show the finished product - the brass of the probe tip, the silver solder line and the tungsten-carbide are all visible in the close-up. These ought to last a good long while.

IMG_20160904_113005.jpg IMG_20160904_114908.jpg
 
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