PCB Eyelet installation tools - PCB Repair - Page 1
Forum section: electronics / repair

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: November 17, 2021, 05:49:29 pm
content: Hello,Have you purchased tools for repairing PCB vias where the core was accidentally pulled from the PCB?I purchased a kit from Chip-Direct on ebay and was not able to get these tools to work properly.Here are their directions for usePCB Rivet Eyelet Tool / PinQuoteNow it could just be me, but I had no luck with this. In fact, the rivets do not collapse as expected.instead, the tool deforms.What I believe causes this is that there is absolutely no chamfer to help guide the edge of the brass rivet outward to form a mushroom and then curl downward to the PCB surface.(See illustration below)Instead the surface of the tool that contacts the rivet is completely flat.it is possible that this tool will only work with special rivets....such as those having a pre formed outward mushroom shape on the tip of the rivet that should expand. However, such a pre shape seems as thought it might interfere with passing through the PCB in the first place. another possibility is that these brass rivets come in a varying degree of thickness such that thicker rivets are much harder to form into a mushroom and curl to the PCB surface?The illustration below illustrates. The Flat tool (as supplied by Chip-Direct) will simply try to Crush the eyelet shaft straight down. This results in excessive force on the tool.The proposed Curved tool on the right has a chamfer that helps the eyelet spread into a mushroom requiring less force and forming a nice circular contact patch to the PCBIf you have tried these tools what was your experience? Did I possibly receive a set that was not properly machined and lacked the chamfering ?I do believe I used them carefully and as directed. have you tried them? What were your results? Can you suggest anything I did incorrectly?Thanks

author: jpanhalt
author_rank: Super Contributor
timestamp: November 17, 2021, 07:20:42 pm
content: On very rare occasion that I have needed to repair a TH plated pad with a rivet, I have used the sets from Circuit Medic (https://www.circuitmedic.com/instructions/INS1064.pdf) and have had no problems. The shop head ends up a little different than the factory head, but they hold and are easily solderable.

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: November 17, 2021, 08:38:02 pm
content: Quote from: jpanhalt on November 17, 2021, 07:20:42 pmLooking at the link you posted, I can see how these can work.This kit uses a pointed tool to first expand the rivet, then a second to push it flat.

author: jpanhalt
author_rank: Super Contributor
timestamp: November 17, 2021, 09:00:21 pm
content: I don't recall you said how you are setting them. I hope it is a small arbor press, not a hammer. I am sure it could be done with a small hammer, but I used an arbor press for better control.

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: November 17, 2021, 09:12:24 pm
content: Quote from: jpanhalt on November 17, 2021, 09:00:21 pmSee the Opening Post.I quoted the manufacturers own directions for use.

author: jpanhalt
author_rank: Super Contributor
timestamp: November 17, 2021, 09:59:51 pm
content: Hey, it was Chinglish. Use a small arbor press (not hydraulic) or a small tack hammer. Those riversts are not 1/8" 2017 aircraft rivets. If you use a hammer, tap lightly to control the compression and forming.

author: wasyoungonce
author_rank: Frequent Contributor
timestamp: November 17, 2021, 11:20:45 pm
content: We use staking sets to fix PCB rivets ....they are all but gone these days. They were used to inset watch jewels etc...cam with little hammers...like a toy but jeez they were good. But sadly expensivehttps://www.ebay.com.au/itm/383023020812I agree on using a slight radius on inset stake tool and over pressuring them easily splits rivets. These days they use a small press.

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: November 18, 2021, 06:19:32 am
content: Quote from: wasyoungonce on November 17, 2021, 11:20:45 pmOh those might work.But the little flat tools I got on ebay .....it's nearly impossible for those to flatten properly.

author: jpanhalt
author_rank: Super Contributor
timestamp: November 18, 2021, 08:14:42 am
content: Quote from: ThermallyFrigid on November 18, 2021, 06:19:32 amThe drawing you posted and the CircuitMedic tool look the same. Maybe a picture would help. (Mine were actually bought from Circuit Technology, which I believe was renamed or acquired by Circuitmedic.)Here's a picture of the tools I use. On the right are the two tools I purchased. The square plate is just a base that holds the bottom set vertical. The small rod is the set. One end is a cone for spreading; the other is flat with a center dimple for flattening. The center dimple keeps it centered in the rivet.On the left are the two adapters I made for by arbor press. The arbor of the press has a hole in it to accept the tail of the aluminum piece. The other end of that piece has a hole to accept the set. The steel piece simply serves as a flat for the back side (factory side) of the rivet.Those tools do not have any curvature as you proposed. They work fine. Here's a picture from MIT:http://fab.cba.mit.edu/classes/863.16/doc/tutorials/PCB_Rivets/The shop side has slightly more ridge to it than the back (factory made) side. My rivets look the same, but I don't have/can't find any pictures of them. Perhaps you just need more practice and a smaller hammer.

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: November 18, 2021, 05:16:00 pm
content: Quote from: jpanhalt on November 18, 2021, 08:14:42 amTHIS is why yours works and what I received will not.The tools I received have no "Cone" side. Nothing to get the rivet spreading so that it can be properly flattened.As I said, it simply tries to CRUSH the rivet center section flat. That will not work.Perhaps if one end had been a cone.Try NOT using the end with the cone first. Then you will get the results I got.

author: jpanhalt
author_rank: Super Contributor
timestamp: November 18, 2021, 05:20:18 pm
content: To save buying a new one, do you have a center punch? Use that as the "spreader."Edit: A scribe or metal pick might also work.

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: November 18, 2021, 10:39:49 pm
content: Quote from: jpanhalt on November 18, 2021, 05:20:18 pmI was going to try that.Thanks

author: vk6zgo
author_rank: Super Contributor
timestamp: November 19, 2021, 12:06:56 am
content: Quote from: jpanhalt on November 18, 2021, 05:20:18 pmBack when I did a fair number of these, that's what I used.Some eyelets are soft enough that hand pressure alone on the punch is enough to spread them OK.The supply of such eyelets & the often needed track replacement material seems to have dried up in Oz.The brand we used back then was "Cir-Kit".

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: November 19, 2021, 12:30:06 am
content: Quote from: vk6zgo on November 19, 2021, 12:06:56 ami think this is a good point.The eyelets I have now may be harder to form. Not sure since this is the first time I'm trying this.What I'm ending up doing is simply drilling the hole to fit the eyelet, then soldering the eyelet into place.

author: sleemanj
author_rank: Super Contributor
timestamp: November 19, 2021, 02:13:21 am
content: I never bought any special tools (and it's been a while since I've used rivets, or made a PCB myself, for shame) and my rivets were cheap chinese 0.8mm probably brass, but if I needed to flatten them(*) I used to use a push-pin (noticeboard pin) to flare the end, then just either gave it a whack with a hammer/punch, or if I was feeling very motivated, take it out to the drill press and chuck up a steel rod with a flat end.I always soldered afterwards mind you.* More often than not I never bothered flattening them at all, just soldered both sides and leave it sticking through the 1mm or whatever, really like a slightly more convenient little-bit-o-wire.

author: t1d
author_rank: Super Contributor
timestamp: November 19, 2021, 12:54:00 pm
content: I take it that your use of the tool is for more than a one-off repair. If you were just doing a one-off, I would have suggested the old method of just passing a wire through the old via hole and soldering it to the traces on each side.

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: November 19, 2021, 04:22:41 pm
content: Quote from: t1d on November 19, 2021, 12:54:00 pmYes,I do quite a bit of electronics repairs and occasionally I get a pulled via core that has to be repaired no matter how careful I amNow for those who might jump to say 'Well then do it right and don't let that happen!!!"lol. Please look up "6 Sigma". Even in robotics and under the highest QC methods errors occur.