snips capable of cutting soic leads? - Page 1
Forum section: electronics / general

author: coppercone2
author_rank: Super Contributor
timestamp: May 03, 2025, 04:45:45 am
content: I hate using hot air. I would like to get some kind of snips that can do SOIC chips. They need a really narrow head. Recommendations?

author: Smokey
author_rank: Super Contributor
timestamp: May 03, 2025, 05:00:16 am
content: scalpel?

author: coppercone2
author_rank: Super Contributor
timestamp: May 03, 2025, 05:32:11 am
content: No I mean like a side cutter with a really narrow head for this job

author: Smokey
author_rank: Super Contributor
timestamp: May 03, 2025, 05:36:38 am
content: Quote from: coppercone2 on May 03, 2025, 05:32:11 am... and I mean cut the legs off with a really sharp scalpel (xacto knife, etc.)

author: coppercone2
author_rank: Super Contributor
timestamp: May 03, 2025, 06:08:41 am
content: I know there must be a tool. Its pain staking for me to use a bladeLike a model from excelta or something. I want to pay. I did this iwth a tool that is a hair too big and I have 3 traces that i need to fix now because it was not getting the correct depth clearance.

author: 5U4GB
author_rank: Super Contributor
timestamp: May 03, 2025, 06:09:47 am
content: As a general answer I'm sure Knipex make some expensive precision-engineered cutter for this, but I'm more interested in finding out why you'd want to do this? You'd need to perform microsurgery on a lot of pins and then be left with little bits of metal solder-tacked onto the PCB that you can no longer easily lift off because they're no longer attached to the package.

author: coppercone2
author_rank: Super Contributor
timestamp: May 03, 2025, 06:10:16 am
content: just swipe it with a iron and they get attached to itIf you have a double sided board or some shit, its painful. I like working with the iron, I don't mind doing 'micro surgury' if it "fits"The freehand shit with the scapel is annoyingIts not surgury. You seat it, and close it. Thats it. You don't need to hold steady. The tip sits on the bottom of the PCB if its thin enough.Its like putting it into a hole, and pressing a button. You don't have to control cut pressure, the tool closes and cuts it off and that wedge pulls it apart ever so slightly.If its too fat, you have to control down pressure. Then you can get a pin thats say 80% cut, and when you remove the chip you can yank a pad.I only want a tool for cutting soic leads. It can be wimpy so long it can handle the soic lead.

author: coppercone2
author_rank: Super Contributor
timestamp: May 03, 2025, 06:17:13 am
content: I have like a dozen different kinds of ultra flush cutters. The problem is the beak shape. They like to make it oval to make it stronger. I need a really acute triangleI was hoping a person has a model they tested to reliably cut SOIC chips out.I am guessing its specialized because it will be only able to handle a puny wire gauge with that geometry.Like I can't tell. This one MAYBE looks good.https://smtsupplies.com/products/excelta-fine-tip-cutter-7271e-small-tapered-tips-optimum-flush-molded-grip

author: Psi
author_rank: Super Contributor
timestamp: May 03, 2025, 06:19:12 am
content: Lindstrom have some precision micro tip cutters.The tip is cut down and much smaller for getting into tight places.I have not used them so dunno how good they are, being Lindstrom expect to pay a bit.https://www.lindstromtools.com/int_en/ergotm-precision-micro-tip-cutters-141-mm-pb_rx-8234_.htmlhttps://www.lindstromtools.com/int_en/ergotm-precision-diagonal-tip-cutters-pb_rx-8149_.html

author: coppercone2
author_rank: Super Contributor
timestamp: May 03, 2025, 06:20:34 am
content: I feel like I would literary need a 3D cad model of the cutter head to be able to buy this from a catalog. No one gives details. The terminology is vauge and unhelpful even looking at $300 cutters.

author: Psi
author_rank: Super Contributor
timestamp: May 03, 2025, 06:24:54 am
content: These ones look pretty narrow, at least in one direction.One important thing with really fine/small/flush/tip cutters is that the cutting surface is much easier to damage. So it's even more important to never let anyone else use them.https://www.lindstromtools.com/int_en/ergotm-precision-diagonal-cutters-with-tapered---relieved-tip-head-pb_rx8137mx-rx8138mx_.html

author: coppercone2
author_rank: Super Contributor
timestamp: May 03, 2025, 06:29:19 am
content: That one looks like the same angle of the one I am using (swanstorm 403). It almost works good. Too fat I thinkI wish someone would spec a fucking angle. It's like they dont own a protractor at the factory

author: coppercone2
author_rank: Super Contributor
timestamp: May 03, 2025, 06:32:39 am
content: How about this thing?https://tronex-tools.com/products/tip-cutters-tip-cutter-extra-fine-tip-razor-flushI swear hot air is pissing me off so bad it seems like some half assed after thought that someone went "HMMM. HOW COULD WE HAVE PEOPLE REPAIR OUR BAKED SHIT?"You would think there would be something better. Like magnetic solder that flows under the chip because the iron has a control magnet in it so you can spot heat a blob of heat that travels along the iron or something, actually focusing the heat. The little game you need to play with heat shields, heat sinks (putty, gels, etc), pre heaters, makes me wanna puke. Its literarly rupe goldberg at this pointor get vendor locked on 'heat keys' from PACE that fit only one particular part using their particular iron.

author: ksjh
author_rank: Regular Contributor
timestamp: May 03, 2025, 06:41:42 am
content: Piergiacomi, an Italian tool manufacturer, makes a wide variety of cutters. They have quite detailed drawings of the tools on the web site:https://www.piergiacomi.com/en/Not sure who sells these outside of Europe.

author: Poroit
author_rank: Frequent Contributor
timestamp: May 03, 2025, 06:46:27 am
content: How about scissors and refine the angle you cut at?https://www.covertel.com.au/products/kevlar-cutter-scissors/?srsltid=AfmBOooF8UEghgMKsXTqfoFFHeqqzTxvpuS5bnF2U2jKLePnLdSyM9HK

author: coppercone2
author_rank: Super Contributor
timestamp: May 03, 2025, 06:48:27 am
content: Does anyone even have fun dealing with SMT parts anymore?I thought it was kinda cool but now its that kinda thing that makes me wonder if its going to lead to a heart attack and kill me in the future. I really start to feel "unwell" after trouble shooting or prototyping some of these parts (like stress). Like god damn give me a break, enough is enough. Magnet wire makes me feel the same way. I started to loath it. I feel like I am past the point of thinking that the ability to work with extraordinary finicky or flimsy things is 'cool'.....And you mean to refine the point of the scissors using grinding?I thought shears would be too wide, even if you make the triangle angle small, that they are just too fat... the SMT part only has a tiny bit of protrusion

author: tycz
author_rank: Regular Contributor
timestamp: May 03, 2025, 07:09:35 am
content: I once had the task of upgrading a flash chip in an 8 pin SOIC package on hundreds of boards. The tech gave me a special soldering iron tip remove the old chips. It looked like a cylinder with an M3 screw hole in it to which he'd attached a thick strip of copper sheet bent into a U shape. It fitted perfectly over the chip and made contact with all the pins at once. It took only a few seconds to desolder a chip with this method. Way faster than using hot air or cutting the leads individually.

author: Simmed
author_rank: Frequent Contributor
timestamp: May 03, 2025, 07:16:32 am
content: Quote from: tycz on May 03, 2025, 07:09:35 ami remember thispace has 1i saw some chinese brand also has it (some years ago)and then there is the HT140 on eevblog 1650 video

author: djsb
author_rank: Super Contributor
timestamp: May 03, 2025, 07:19:56 am
content: Proxxon Micro Sonic cutter?https://www.proxxon.com/en/micromot/27300.php

author: coppercone2
author_rank: Super Contributor
timestamp: May 03, 2025, 07:44:07 am
content: that sonic cutter looks scary I don't like sharp things too much lol. That one looks like it can get you into the ERI keep thinking about it and that Razor -flush one looks good. Of course I am gonna get it and its going to turn out to 20 inches long and actually a bolt cutter.........................................but I just spent a better part of an hour making 'traces' from flattened 30 gauge single strand wire to repair this shit and I guess I need to take a plunge soon.Actually, with a knipex parallel jaw pliers, and an assortment of wire (probobly 32, 30, 28 and mayyyybe 26 awg wire, you can make some nice 'traces' that can be epoxied on. I actually like how they cmawe out. Bend and flatten and it comes out looking OK. For longer traces you probobly wanna get the maximum size parallel jaw plier wrench so it can be used as a 'press' with a wide work area. I made those up and it feel slike the room temperature dropped 15 degrees lol, almost bought a fucking pace cirkit, but i think if you bend and flatten it acutally comers out nicer then treeing to bend a flat

author: 5U4GB
author_rank: Super Contributor
timestamp: May 03, 2025, 09:19:21 am
content: Quote from: djsb on May 03, 2025, 07:19:56 amThose types of cutters are meant for cutting relatively soft materials, they're used in crafts and modelmaking. You can also get them from the usual crapvendors for much less.I suppose an FIB workstation for this is overkill?

author: Gyro
author_rank: Super Contributor
timestamp: May 03, 2025, 09:33:13 am
content: I sometimes use a very thin shim, narrow enough to fit between the two rows of legs, cut with scissors from a razor blade. This is thin enough to fit under the package and by rolling a ball of solder along one row of pins you can gently slide the shim between the legs and pads. Being stainless steel, the solder won't stick to it. Once one row is isolated, it's a simple matter to roll a ball of solder backwards and forwards down the other row of legs to float the SOIC off.Unless the SOIC has been pushed hard down during hand soldering, there is enough space to slide the razor blade shim through the solder fillet between pads and legs with minimal force.

author: coppercone2
author_rank: Super Contributor
timestamp: May 03, 2025, 09:45:32 am
content: Quote from: 5U4GB on May 03, 2025, 09:19:21 amlmfao it really is not if its in the budget, this problem is mega. Maybe that can do smaller packages too

author: Kean
author_rank: Unknown
timestamp: May 03, 2025, 01:05:23 pm
content: I bought a bunch of cheap ones on AliExpress ($20 for 10) and then ground the sides down to make them better for getting into tight spaces or for depanelling PCBs.I use Knipex as my primary cutters, but these other ones come in handy. I also use soldering tweezers, wide soldering tips, or ChipQuik alloy whenever possible to avoid potential PCB damage.I know someone who swears by using toenail cutters

author: eugene
author_rank: Frequent Contributor
timestamp: May 03, 2025, 01:16:56 pm
content: Quote from: coppercone2 on May 03, 2025, 06:29:19 amDo you have a grinder?

author: wraper
author_rank: Unknown
timestamp: May 03, 2025, 01:40:47 pm
content: Quote from: coppercone2 on May 03, 2025, 06:29:19 amToo fat? A bit thinner and jaws will become needles. I cut SOIC with a quite a bit fatter 8147.

author: wraper
author_rank: Unknown
timestamp: May 03, 2025, 01:44:01 pm
content: Quote from: coppercone2 on May 03, 2025, 06:20:34 am

author: PlainName
author_rank: Super Contributor
timestamp: May 03, 2025, 02:06:06 pm
content: A cutter seems a bad idea to me: there will be stress on the pad from the cutting since the leg is very short and there is no space for the cutter blade to fit (so the leg must move for the blade to close).I would second the earlier suggestion of the stainless shim. You can get the tool specifically designed for this for peanuts from Ali (and no doubt more expensively elsewhere). Just a very thin and flexible blade. Use a normal soldering iron on the pin and slide this thing under, then move along. The pins are then not soldered to the pads and the chip just falls off. Quick, simple, no damage.Blades in image below look like solid thick things, but they are super thin and very, very flexible.

author: tooki
author_rank: Super Contributor
timestamp: May 03, 2025, 02:16:12 pm
content: Weller Erem 2842E is expressly listed for “SMD”. Other manufacturers also make similar shape heads.

author: eliocor
author_rank: Unknown
timestamp: May 03, 2025, 02:20:52 pm
content: Weller Erem 570E:Weller Erem 2470E:

author: Psi
author_rank: Super Contributor
timestamp: May 03, 2025, 11:20:24 pm
content: I've cut SOIC pins cleanly using a scalpel blade under the microscope before, or using my 8141 Lindstroms and it worked fine.Does the OP have a microscope, it's really needed for working with SMT.There's a lot of fine detail work that you don't know you can do with normal tools until you have a microscope and can see what you are doing close up.Trying to work at the pin level without a microscope is a recipe to destroy things.

author: coppercone2
author_rank: Super Contributor
timestamp: May 04, 2025, 07:16:31 pm
content: i got 2470e. I was gonna get the other one but ESD is important so you don't damage the rest of the circuit. I hope it works, I try to always stick with ESD tools. the 2842 looks kinda fat. If it does not work I might try again because this problem really needs to get solved.Next up I will have to find one that works for MSOP. I think that razor flush one might be a bit slimmer, but it would also need ESD safe handles added.Actually MSOP one might be really useful. The smaller the part the closer you will have some petulant micro capacitor nearby. That seems small enough that you can actually make a small soldering iron attachment to remove them though.The SOIC chips are way bigger then a iron tip. I imagined a bowtie shape, so you can get tweezers to hold the chip and the long ends to heat the leads for removal. I wonder if you can make it out of brass.

author: tooki
author_rank: Super Contributor
timestamp: May 04, 2025, 07:55:32 pm
content: Quote from: coppercone2 on May 04, 2025, 07:16:31 pmJust use two soldering irons and big blobs of solder. Seriously. That’s a 3x3mm package, super easy to desolder that way.

author: coppercone2
author_rank: Super Contributor
timestamp: May 04, 2025, 08:17:42 pm
content: I was literarly thinking you can machine a piece of brass with a square on it that will wick the part up.The problem with all these 'chop stick' methods can be glued parts. If it fits you can twist it.I have hakko hot tweezer iron, and resistweeze from pace (bigger, crude)... I bet they have some attachment for it too. Well the hakko is too puny, its like for 0201 etc. The pace should do it if I can get the part

author: coppercone2
author_rank: Super Contributor
timestamp: May 04, 2025, 08:30:16 pm
content: dohhhthey sell a soic remover for tweezers that I likeOh well. It's expensive though. I think its just nichrome soldered to brass with nickel bearing braze. Their prices are so obscenehttps://framebuildersupply.com/products/harris-50n-silver-brazing-alloy-1-ozI am thinking about it. Carve out a fire brick to make a fixture to braze a strip of nichrome to some brass wires or something. These prices are making me a crazyLike I said, bending and flattening a wire in a vise can make a trace. Ideally I believe you would want to boil it in some copper black and polish the top side to get a true PCB trace that bonds well, so you get the roughed oxide surface on the bottom for gluing. I made a snake shape PCB trace out of 30AWG wire. Its kinda beefy but they lay flat on the PCB and fit in the 'hole' where the old trace used to be if you are precise with bending. Takes the bodge wire to a new level, making it into a real planar conductor. If you black it, and use good epoxy, the bond might be very close to real PCB strenght. Damn this technique makes me happy. I almost want to take apart some old 'repairs' i made with thin wire and properly re-trace the boards with these DIY micro bus bars. You can probobly re-aneel them too after pressing flat. But keep in mind, this gets you a true, no horizontal distortion 90 degree or more bend if you like. Shit lays flat if your vise is good.I am also loving this xcelta micro spatula I got for transfering glue.

author: Smokey
author_rank: Super Contributor
timestamp: May 04, 2025, 10:57:03 pm
content: Quote from: PlainName on May 03, 2025, 02:06:06 pmJust in case someone happens on this thread and gets this far without understanding what game we are playing here...Essentially everything here IS a one form of "bad idea" or another. The whole premise is we are going to ignore the "right" answer and try to come up with "alternate" methods just because...The "right" answer to this problem is pretty obviously hot air or a purpose designed soldering iron tip.

author: coppercone2
author_rank: Super Contributor
timestamp: May 04, 2025, 11:09:31 pm
content: I mean the repeated heat also stresses the pad, probobly not as much but it still has a finite life. I think the copper lead is pretty mushyI will let you know if I see pads being ripped off. I think I won't see it unless the PCB is abysmal quality if its clean cut (no wrestling the chip out to get a 90% cut broken through)It might be a bit easier to over heat it with the hot air gun too because you can easily be too close (iron is regulated, hot air gun is over heating if you mess up the distance its set to)I wonder if one day there will be some awesome paper pin metal saw that can cut under a BGA part while floating over some kind of air curtian it makes for itself with a special coating..

author: thm_w
author_rank: Super Contributor
timestamp: May 05, 2025, 10:36:19 pm
content: Hot air stations are temperature regulated at the tip, the further away you go the colder it will get.If you have issues with distance, you can use an articulating arm or stand to hold the hot air wand while the board sits on a flat table. How most BGA reworks stations are setup. Maybe $20-50.

author: PlainName
author_rank: Super Contributor
timestamp: May 05, 2025, 11:16:57 pm
content: I like the way the smoke from the soldering iron curls in exactly the same way regardless of board and iron and solder orientation. Must be magic flux or something.

author: coppercone2
author_rank: Super Contributor
timestamp: May 06, 2025, 12:32:08 am
content: thats some defined physics effect that I forgot the name of. The one that always makes smoke go into your nose if you don't have air flow, something to do with a draft... I thought it began with the letter Cor photo shop / ai ??https://www.eevblog.com/forum/other-blog-specific/why-does-smoke-from-a-soldering-iron-always-go-towards-your-face/maybe it can be used for soothsaying?

author: PlainName
author_rank: Super Contributor
timestamp: May 06, 2025, 06:41:47 am
content: I would have said photoshop, but the bottom left photo has the magnifier not quite right, so perhaps AI.

author: elektryk
author_rank: Regular Contributor
timestamp: May 06, 2025, 09:44:10 am
content: Quote from: tooki on May 04, 2025, 07:55:32 pmI really like that method, SO8 can be even desoldered with single iron and quite big solder blobs if you are quick enough.

author: tooki
author_rank: Super Contributor
timestamp: May 06, 2025, 06:26:35 pm
content: Quote from: coppercone2 on May 04, 2025, 08:17:42 pmYep. Or better still, copper. Even better if you somehow have the ability to plate it so that it lasts.Quote from: coppercone2 on May 04, 2025, 08:17:42 pmHow often do you see glued-down SMD parts anymore? That is needed for wave soldering SMD, but we largely reflow solder them nowadays.

author: tooki
author_rank: Super Contributor
timestamp: May 06, 2025, 06:29:03 pm
content: Quote from: coppercone2 on May 06, 2025, 12:32:08 amWell in the stock photos it's faked anyway.Are you thinking of the Coanda effect? That was one hypothesis, but it proved to be incorrect.Here's the writeup and video link for the guy who figured it out:https://hackaday.com/2020/06/01/why-does-solder-smoke-always-find-your-face/

author: coppercone2
author_rank: Super Contributor
timestamp: May 06, 2025, 08:39:52 pm
content: yeah that sounds rightI thought it might be related. I noticed even if I have air purifier going the solder smoke has enough draft to go away from me, but I have the little hakko benchtop extractor too, so I never really considered it.

author: thm_w
author_rank: Super Contributor
timestamp: May 06, 2025, 10:56:33 pm
content: Quote from: coppercone2 on May 06, 2025, 08:39:52 pmGarbage, get a decent extractor if you are soldering on a daily basis.

author: 5U4GB
author_rank: Super Contributor
timestamp: May 07, 2025, 10:28:00 am
content: Quote from: coppercone2 on May 04, 2025, 07:16:31 pmWhen an eel bites your thigh,And you bleed out and die,That's a moray!Apart from that, why is there an eel in your post?

author: 5U4GB
author_rank: Super Contributor
timestamp: May 07, 2025, 10:36:27 am
content: Quote from: coppercone2 on May 06, 2025, 12:32:08 amSame reason why bread always falls on the buttered side down.Which is actually quite useful, if you tape the bread to a cat, which always lands on its feet, the combination will sort of hover in mid-air spinning around and you can run a small dynamo off it and recharge your cellphone.

author: coppercone2
author_rank: Super Contributor
timestamp: May 07, 2025, 01:48:41 pm
content: because it has to go into a weird hole to bite things like the pliersthe head shape is what I need. Most pliers are generic fish that can't go into holesAnd the order got screwed up so I don't have anything to test

author: joeqsmith
author_rank: Super Contributor
timestamp: May 11, 2025, 04:15:04 pm
content: Very old Xcelite 170M cutters and new Plato 170. While you can still buy the Xcelite brand, I doubt they are made here anymore.As far as SOICs, I will stick with a heatgun. Faster and easier on the board with no damage to the IC.

author: tooki
author_rank: Super Contributor
timestamp: May 12, 2025, 10:47:27 pm
content: Quote from: joeqsmith on May 11, 2025, 04:15:04 pmIndeed, all 11 Xcelite cutters currently in stock at DigiKey list* China as the country of origin. :'(*Digikey pro tip: while product listings don’t show COO, it does appear in lists, so just temporarily add a product to a list to see where it’s actually from.

author: coppercone2
author_rank: Super Contributor
timestamp: June 17, 2025, 03:28:18 am
content: 2470E works great

author: eliocor
author_rank: Unknown
timestamp: June 17, 2025, 05:41:52 am
content: Quote from: coppercone2 on June 17, 2025, 03:28:18 amI told you so*: to my experience, EREM snipers are a warranty!*) even if I prefer the 570E model (I have both) for its soft handles