Test Renishaw TP2 modules?

[derrickcoyne]

Hello all,

Is there any way to test and see if a TP2 module is good? I have 11 modules that are either suspect or marked bad. I need to verify which ones are before I ask my manager to sign off on ten grand worth of RBE and have it be that they didn't all need it.

Thanks!
derrick

[KIRBSTER269]

test them out with a ring gauge.

[louisd]

Aren't tp2's adjustable and pretty much indestructible? I've honestly never had to use one, but have heard that they are super durable.
https://www.renishaw.com/cmmsupport/...s-guide--27698
Trigger force adjustment - TP2 and TP6


The trigger force of TP2 and TP6 probes is preset by Renishaw at an optimal performance setting, but can be altered if necessary as follows:

1. Remove the probe from the probe head on the quill of your CMM.
2. Insert a 1.5 mm AF Allen key (supplied with every probe) into the hole in the centre of the M8 thread until you locate a grub screw.
3. Adjust this grub screw to alter the trigger force of the probe:

• Clockwise increases the trigger force
• Anticlockwise decreases the trigger force

[derrickcoyne]

That sounds simple enough. The issue I'm having however is that if I roll the TP2 on a surface plate with a probe screwed in, the probe visibly wobbles around the center axis, drawing a spiral in the air. The ones i know are good and are in use do not wobble, they line they draw in the air is straight. How will I know if it needs to tighten or loosen?

[louisd]

If they are bent, there's nothing you can do to fix them. they are ruined, unless you forcibly un-bend them somehow back to being straight without damaging the internals. the adjustment screw will only change the sensitivity of when the probe detects a hit point with the part.

[Marken199]

I believe a TP2 is a probe and not a module. Did you mean TP20 modules? Also I didn’t think they RBE TP20 modules.

[gibsonridge]

test each direction of contact with a gram force gauge , verifying all directions are of equal force.

[Matthew D. Hoedeman]

tighten-loosen will not fix a wobble. Change the build in the TP2, see if different components wobble. If it is bent components, no big deal. I don't know how the guts of a TP2 could be skewed like that, it would take one HECK of a direct-line crash to bent the pins inside. BUT, if a pin inside is bent, it should still function correctly, you will just have a probe that isn't straight. All you need to do is make sure you are not shanking out when taking measurements.

BTW, a TP2 can last 10 years or more. The only thing you really need to worry about in a TP2 are the 'ruby' pivot bearings inside (per a local guy who used to fix TP2's for us), as long as they don't crack, it's good to go.

[derrickcoyne]

Some of these are ancient, like 15+ years. I found several in a cabinet that were marked bad, but I don't know if that was tested, or it was just assumed. I really want to avoid justifying a 10k purchase requisition if I can avoid it. If it does wobble, will the measurements still be accurate once it is calibrated?

[Matthew D. Hoedeman]

yep. As long as the wobble isn't due to something loose, something bent, is just fine. The probe doesn't have to be straight, it can be bent in just about any configuration. I've had to make 'custom' probes by bending one like a fish hook (and not from a crash) to check odd-ball parts from a local machine shop

[tking]

Sometimes they just get picky about rearming after a touch and folks call 'em bad. I guess they are if the machine stops and wastes time (production environment / operator leaves). I didn't trust them when they did that to me.

[Matthew D. Hoedeman]

Sometimes they just get picky about rearming after a touch and folks call 'em bad. I guess they are if the machine stops and wastes time (production environment / operator leaves). I didn't trust them when they did that to me.

yeah, that's what our local guy fixed, opened them up, cleaned all the contacts, very small drop of oil on the ruby (?) bearings, put them back together.