hard, sharp meter probes that can withstand being used to scratch components? - Page 1
Forum section: electronics / testgear

author: thom
author_rank: Contributor
timestamp: December 15, 2022, 03:26:04 pm
content: Howdy everyone,I repair lightning damaged devices for a living, and part of the diagnosis process is, for example, testing a row of 30 mosfets, and each one that tests bad gets a mark scraped in it with my probe tip so I know which ones to pull. I've had dozens of different cheap old aliexpress probes over the years, some with properly hard sharp tips, most with soft tips, but they all get worn down and sharpened regularly. I am wondering if there are any sharp probes with metal hardened enough to suit this specific use case?alternatively, if you think there is a more efficient method for efficiently marking chips as I read them without having to drop my probes and pick up a pen, I am all ears!I've got a pomna 6431 set coming with the hopes that the SS tips are higher quality than the chinesium I am used to

author: bdunham7
author_rank: Super Contributor
timestamp: December 15, 2022, 03:32:20 pm
content: The Probemaster gold-plated SS probes are really sharp. They'll stab you quite easily and they come with little safety covers on them to keep them from poking through their packaging. I can't say how long they will stay that sharp being used as you state, but mine are still dangerously sharp after years of normal use.https://probemaster.com/8000-series-test-leads-only/

author: joeqsmith
author_rank: Super Contributor
timestamp: December 15, 2022, 03:46:56 pm
content: I get the old dental picks and grind the ends. Add wire and some shrink tubing.If you want to just buy a set, I have some stainless like these that can be sharpened as well:https://www.pomonaelectronics.com/products/dmm-test-leads-and-probes/probe-tip-040-quad-point-pogo

author: thom
author_rank: Contributor
timestamp: December 15, 2022, 04:01:52 pm
content: Hi Joe, do you mean you have a 3rd party source for ponomoa compatible SS tips? I bought the full set, and if the SS tips are good, it would be nice to be able to buy just those instead of having to buy the 10 pc kit!as an aside, I recognize you from youtube, your videos are fantastic, thanks for the effort you put in!

author: 2N3055
author_rank: Super Contributor
timestamp: December 15, 2022, 04:22:43 pm
content: Like Bdunham7 said, just buy Probemasters.. They are very good quality, very sharp (scarry), made of stainless steel.Pomona 6341 are expensive piece of crap. I have both and Probemaster is superior quality..

author: thom
author_rank: Contributor
timestamp: December 15, 2022, 04:39:29 pm
content: I went with the ponoma because of the replaceable tips, I wear those down like crazy, but I'll get a set of the probe masters as well and see if they can survive the abuse, but I am currently most intrigued by joe's excellent idea of using dental picks

author: joeqsmith
author_rank: Super Contributor
timestamp: December 15, 2022, 04:48:23 pm
content: Sorry, I do not. The ones I use are branded by Fluke. Many people do not like the quality and fine leads. For surface mount, I like them.https://www.fluke.com/en-us/product/accessories/test-leads/fluke-tp912One work around may possibly be sewing needles. I often use them to make custom probes. They are very inexpensive and have several sizes available. You may find some with the proper OD that you could just snap off and use with existing probes. You can also solder to some of them.Link showing a typical use of sewing needles:https://www.eevblog.com/forum/testgear/sub-$1000-vna-for-antenna-matching/msg4551707/#msg4551707

author: joeqsmith
author_rank: Super Contributor
timestamp: December 15, 2022, 04:50:21 pm
content: I suspect that the picks that are sold at flee markets are not the quality of steel you will find at the dental office. It wouldn't hurt to ask your dentist the next time you are in for a visit.

author: joeqsmith
author_rank: Super Contributor
timestamp: December 15, 2022, 04:58:45 pm
content: I've wondered about using a Tungsten electrode for welding but have never tried it. The rods have a smaller diameter than the dental picks.

author: Fungus
author_rank: Super Contributor
timestamp: December 15, 2022, 05:12:44 pm
content: Do you also knock screws in with a hammer?Buy a proper sheet metal scribe and use that. You can probably tape a wire to one and use it as a probe.(or just accept that you're going to need to get new probes every month because you're lazy...)

author: thom
author_rank: Contributor
timestamp: December 15, 2022, 05:18:13 pm
content: looks like the pomona probes have 1.02mm tips, which could probably socket 1.0mm electrodes. I'm going to see if any of my local joints have any in stock I can try fitting in them, but I think you might have properly solved my problem. while the probe masters are sturdier, looks like they accept 1.36mm tips, which I doubt are going to be easy to find a tungsten mate for.https://sunstonewelders.com/orion-micro-tig-welding-electrodesI've gone the sewing needle route before, and find that the tips break off very fast if used for scraping, to say nothing of how frequently they draw blood.

author: joeqsmith
author_rank: Super Contributor
timestamp: December 15, 2022, 05:23:27 pm
content: Quote from: thom on December 15, 2022, 05:18:13 pmI'm interested in hearing how it works out. Maybe invest in a soft wheel to sharpen them if you don't already own one.***Forgot, attached is a sheet metal scribe for Fungus. Note the predrilled hole to attach your test lead wire to. Also when one tip starts to dull, you just rotate to the next. Many benefits.

author: Fungus
author_rank: Super Contributor
timestamp: December 15, 2022, 05:43:08 pm
content: Quote from: joeqsmith on December 15, 2022, 05:23:27 pmMaybe they have a different name in your country.I was thinking more of this:https://www.aliexpress.com/item/4000257756923.html

author: joeqsmith
author_rank: Super Contributor
timestamp: December 15, 2022, 06:18:24 pm
content: Quote from: Fungus on December 15, 2022, 05:43:08 pmMost people realize smart ass posts get smart ass responses but maybe its different in your country.

author: james_s
author_rank: Super Contributor
timestamp: December 15, 2022, 06:56:03 pm
content: Sounds like what you need is a scratch awl, or just use a permanent marker, that's what I do.

author: tautech
author_rank: Super Contributor
timestamp: December 15, 2022, 07:39:37 pm
content: Quote from: james_s on December 15, 2022, 06:56:03 pmMakes more sense to buy a pack of these if needing to place an obvious mark on so many fried components:https://www.ebay.com/b/Sharpie-Pens-Markers-for-Artists/28109/bn_56922649One can easy spend more on a set of good DMM leads than a 6 pack of white markers.

author: thom
author_rank: Contributor
timestamp: December 15, 2022, 08:16:32 pm
content: I will explain this to clear up any confusion about my situation. I literally mark upwards of 1000 of these components a day, 6 days a week. with how I do it, a component tests bad, I scratch it with the probe already in my hand, and test the next component.if I were to use a sharpie, for example, I would have to put down both probes, pick up the sharpie, take off the lid, mark the component (make sure it's the right one becasuse now I had to take my eyes out of my microscope), put the cap back on, pick up my probes, go back to the scope and carry on.if you could do that all in 3 seconds, it would add about 50 minutes to my average work day.don't mistake laziness for efficiency.anyhow, I'm going to try this tungstun bit approach, but if that doesn't work, making a probe out of a tungsten awl is an excellent back up plan

author: Bud
author_rank: Super Contributor
timestamp: December 15, 2022, 08:57:16 pm
content: Gee..., you guys have that many lightnings in your location?I' think a pair of machinist scribes with cold welded to them multimeter wire leads would set you for long time.

author: floobydust
author_rank: Super Contributor
timestamp: December 15, 2022, 08:57:50 pm
content: Pomona6341I dislike because they have an aluminium tube for the probe sheath and the dissimilar metals sucked for contact resistance and it's soft.OP when you get yours, please check if this has changed as I complained to Pomona.Their gold plated probes don't have this problem but are spring-loaded.Best I've used is Huntron Tracker MP20 or MP10 I can't remember but I thought they are tungsten and telescoping.For poking through conformal coatings, I have best luck using SS dental picks with an attached test lead.Another approach is making your own probe using sewing needles and old ball point pens. I've done that on the cheap.

author: thom
author_rank: Contributor
timestamp: December 15, 2022, 09:09:22 pm
content: they should be here on monday, if you have any specific thing you would like me to do to test them, let me know! if the socket is in fact soft aluminum, I have a feeling no matter what tips I use, I'm going to wear it out fast just from the way I use these things, but we will see.I've never even heard of those huntron probes, I'll add those to the list I'll try if these pomona don't live up

author: DC1MC
author_rank: Super Contributor
timestamp: December 15, 2022, 09:10:19 pm
content: Poor man (me):https://www.tag-connect.com/product/non-slip-probe-tipsRich man/companyhttps://www.toolsource.com/leads-and-probes-c-1321_408_511/penetrator-tungsten-tip-extender-p-149411.html

author: notsob
author_rank: Frequent Contributor
timestamp: December 15, 2022, 09:35:19 pm
content: You could try acupuncture needles - I've seen home made test leads using them

author: james_s
author_rank: Super Contributor
timestamp: December 15, 2022, 10:42:52 pm
content: What on earth are you doing that has 1,000 bad components a day? At that volume it seems like it would be worth automating the process, unless it's all different types of devices being tested. I knew a guy that worked at a company that made automated flying probe test machines that could do that sort of thing.

author: thm_w
author_rank: Super Contributor
timestamp: December 15, 2022, 11:04:57 pm
content: Quote from: james_s on December 15, 2022, 10:42:52 pmYeah getting mixed messages here.Also FETs are often ground or Vcc referenced, so you can often clip one lead onto ground, then test with the other.

author: tautech
author_rank: Super Contributor
timestamp: December 15, 2022, 11:07:14 pm
content: Quote from: thm_w on December 15, 2022, 11:04:57 pmYep, switched on ones (excuse pun) would have one lead with a grabber to free one hand.

author: thom
author_rank: Contributor
timestamp: December 16, 2022, 12:08:33 am
content: POE switches are a common one. can't really automate a repair shop, every board is damaged in a different way (and currently I'm doing about 50 different products), and I'm not just testing fets, I'm testing diodes, current sensors, shunts, etc.@DC1MC: wow, those tungsten tips are pretty much exactly what I need, THANK YOU!!!!!!

author: DC1MC
author_rank: Super Contributor
timestamp: December 16, 2022, 03:19:57 am
content: Quote from: thom on December 16, 2022, 12:08:33 amMost welcome, whatever of of them you buy please post pictures and report about quality, with all the cr@p going in the industry is goo to check if the quality remains.Cheers,DC1MC

author: floobydust
author_rank: Super Contributor
timestamp: December 16, 2022, 07:15:40 am
content: Quote from: thom on December 15, 2022, 03:26:04 pmIt's winter in Canada, no lightning happening for 6 months!This summer had three mild storms total, pretty much nothing.

author: thom
author_rank: Contributor
timestamp: December 16, 2022, 03:39:30 pm
content: 95% of my clients are in the US, but regardless, wind itself can be enough to cause massive ground po0tejntial differences between the top oif a poorly grounded tower, and the ground. this alone is enough to blow the equipment I work on.also, I don;'t know what part of canada you are from, but my lab had 8 days without power from a single storm this summer, we had trees blocking roads in town for even longer.

author: thom
author_rank: Contributor
timestamp: December 20, 2022, 12:40:10 am
content: doesn't look like aluminum, but it is a very soft metal. the injection moulding is dollar store quality, shockingly terrible for such an expensive set of probes. poking a solder pad on 2 wire with the SS tips gives me about .163ohm, .104ohm with the gold pogos. for a simple guy like me, that's what I call "very nice". I imagine I'll wear the SS tips down in short order, so I'll be ordering the 1.0mm tungsten electrodes and we'll see how they work and I'll update this thread periodically

author: Black Phoenix
author_rank: Super Contributor
timestamp: December 20, 2022, 03:33:00 am
content: I remember that Fluke had some hardpoint probes, the TL75. That's their most basic tip set. Don't know how easy they leave a mark in the components if you want to scratch it but the tip is definitely difficult to bend (I had some laying around and tried and sure enough you need some pliers to damage the tip).The other probe I use and it's definitely pointy, to the point (pun intended) I have to use tip sleeves to protect against damage on the case or physical injuries. The tips are very hard, being made of stainless steel. That's the TP220 that needs a the TL224 or equivalent 4mm shrouded leads to be used.I don't know how much is needed to make the pointy tip get dull, since I don't use my DMM probes as a marking tool.

author: thom
author_rank: Contributor
timestamp: January 10, 2023, 05:21:50 pm
content: UPDATE: thhe tungsten electrodes were perfect. these are the ones I bought :https://sunstonewelders.com/orion-micro-tig-welding-electrodesand I can say that they are phenomenal. I shaved 2cm off the bottom and they outperform EVERY tip included with the pomona probes.on a different note, the pomoina SS tips have a beveled rear end and make shite contact with the probes themselves, I think that might be the problem people are having with those, since the gold plated tips have a flat bottom

author: joeqsmith
author_rank: Super Contributor
timestamp: January 10, 2023, 05:51:29 pm
content: Thanks for the feedback.

author: artag
author_rank: Super Contributor
timestamp: January 10, 2023, 09:26:47 pm
content: Doesm anyone make test probes that will accept the standard-sized spring-loaded probes used for ATE fixtures ?They come in a big variety of tip types.