mechanically strongest soft solder?

[coppercone2]

I want to solder on some stuff to a copper block, that also has resistors soldered to it.

Is there a solder that has similar melting point to lead or lead free electronics solder but is stronger mechanically despite decreased electrical performance?

It has to be in the same ballpark as electronics solder melting point. But this would be for mounting hardware, where no current should go and EMI is not relevant.

Also, it can't be gold bearing, because its way too expensive.

70/30 solder is a hair stronger. But that's not worth it.

[coppercone2]

idk the specification of PSI

They seem to compare it that way on tables. used for glue also

and I don't care if it leaks or not its just a bracket

[coppercone2]

I am thinking either kappzapp 3.5
https://www.kappalloy.com/solder-alloy/kappzapp-solders/kappzapp3-5a/

or bridgit
https://www.rhsupplyco.com/buy/product/harris-products-group-bridgit-lead-free-solder/136763


I used bridgit before, the eutectic nature of kappzapp 3.5 seems preferable to this application since I am not filling a gap.

kappzapp 7 is slightly stronger, but I think I prefer the eutectic.

Anyone got any other ideas for similar melting point range for copper to copper or copper to brass? can we get 20k psi?

[bdunham7]

Eutectic silver solder will probably give you the most reliable strong joints at temperatures near normal solder.  There won't be a huge difference, however solder is actually pretty strong if it is done right--which it often isn't.  A jewelers silver solder will be stronger but will have much higher melting point and may contain cadmium in some cases.  The advantage of using something like that is you can do the mechanical soldering first and subsequent electrical soldering won't remelt it.

can we get 20k psi?

IDK, that's pretty ambitious for a regular copper block to some random bracket with a flat joint.  Where did you get the 20ksi figure? 

[coppercone2]

but its already brazed. It needs both a electronic mod and a mechanical mod.

AND I am 100% sure I can do this with regular solder I don't need the strength I just feel like shopping. I was gonna buy another roll of bridget because I am down to about 3 inches, but I don't mind buying something new. OFC bridget is 1/4 the price

[jpanhalt]

@coppercone2

Are you sure that brazing is less conductive than leaded or lead free solder?  Your data or citations would help. I suspect brazing will give both more strength and equal or better conductivity per volume of fill.

[coppercone2]

THe thing is brazed already I need mods that involve attaching a bracket and attaching parts. I want the best thing to attach. I am not going to mess around rebrazing this thing.

Braze is better in every way but I am not going to get this that hot


However i did notice bridget is 460F and lead is much lower. If I attach the bracket with bridget I have quite a temp range before I have to solder on the parts. So I can break up the job.

With 420F and 360F that is a bit close. Feel alot better about 100F vs 60F. That should hold even with dodgy temperature control. That is 50C vs 33C difference, which is pretty solid.

and you can make repairs more comfortably on the electronic parts with the extra margin.

[T3sl4co1l]

Soft solder maxes out around 5k PSI, mostly tin with a bit of copper and silver, maybe antimony.  Whatever alloy designations those include, but SAC305 isn't bad, mechanically.

Epoxies are comparable, the longer-cure and industrial kinds anyway.  Surface prep is paramount.

No lead alloys are particularly strong, AFAIK.  More or less for similar reasons, as tin and lead aren't very strong crystals (low binding energy gives low melting point and low shear strength, even when slippage planes are frustrated by alloying), though tin happens to be the stronger of the two.  (Also, this kinda despite both having rather high boiling points, but I mean it's not everything, materials are complex.)

Brazing takes place at higher temperatures.  There aren't really any alloys of importance, for these base metals, until you get to silver-based ones that work around red heat and up.  They are very strong in comparison, often stronger than the base metal (certainly compared to the yield strength of pure copper), comparable to lower steels.  (Note that the base metal ends up annealed after brazing; you can't do much heat treatment, nor any mechanical working of it.)

There are zinc alloys, which are best suited to aluminum; but zinc tends to be a bit brittle.  A lot of "brazing" alloys for aluminum, tend to be more like shallow welding: say, Al-Si eutectic plus fluoride flux, with melting point just barely below the base metal -- not really usable by hand, but common in industrial processes.

Because soft solders are weaker than base metal, they're best used in large, wide joints; lap joints, pin-in-socket joints, etc.  Prevent peeling failure by suitable joint design

Tim

[coppercone2]

What do you mean 5K PSI?

The link for that solder I linked says 14K. The bridgit datasheet is like 13K.

The Zapp soft solder (420F melting) lists 15K for Copper and 28K for stainless steel joints.

Is there some kind of fraud going on like with compressor CFMs?

Tensile Strength (Copper):
   

14,000 psi

Tensile Strength (Stainless Steel):
   

25,000 psi

Shear Strength:
   

11,600 psi

[coppercone2]

I was also hoping someone knows some exotic brand that has even better specs (gold does, its like 40k)

[T3sl4co1l]

Maybe I remember a bit low? Lemme see here.

Basic Sn63 around 5, well, 6: https://www.matweb.com/search/DataSheet.aspx?MatGUID=9e382af924de44ffb4eb42027ca1436d
Sn62Ag2 about the same, 6.2: https://www.matweb.com/search/datasheet.aspx?MatGUID=15b6a001052c4ec98896e839da7f5b75
Clearly, one of these is wrong: https://www.matweb.com/search/DataSheet.aspx?MatGUID=7f7fb170f75d480ca183c17a4c7574a7
Not very many of the results in their database seem to have tensile strength listed.

Kind of an odd article, not sure what it's written for, or how well supported it is, but discusses the process some at least:
https://www.osti.gov/servlets/purl/1347531
Seems to suggest joints can be stronger than the base metal but doesn't really discuss either thing.

This article is more in line with my expectations: http://files.aws.org/wj/supplement/WJ_1976_10_s323.pdf but doesn't mention joints can be stronger, or, seem to find them stronger than base filler at all.

The impression seems to be that joints can be stronger than the base metal, but I'm not seeing a reference supporting that.  But go figure, Google is terrible; a top result is a Quora question that's mostly bot-generated (and the possibly-not-bot-generated content wholly lacks insight into the matter).  We can go to a horse's mouth and see some data,
https://lucasmilhaupt.com/Lucas/Technical-Documents1/Silvabrite100TDS2018English.pdf
I *think* they mean 1/2" tube (0.5" actual), which will have a 1/2" overlap area, which comes to ca. 10 MPa.

Harris doesn't appear to give any, like actually zero technical data at all, on their Bridgit product.  Composition and temperature, sure, but strength?  You'd think, you know, claiming it's stronger than anything else, they would proclaim prominently what the actual number is?  In the absence of such data, I can only assume it's because it's not actually any better, and as far as I should be concerned, it's marketing fluff, no different from any other alloy of comparable mixture.

Incidentally, this raises an important point, solder creeps and must be loaded quite gently to last a long time.  It's possible there are larger numbers due to intermetallic reactions, basically cementing the joint together (think of how hard it is to wrench copper pipes apart by reheating them -- often by heating far too much, exacerbating intermetallic growth!), at the expense of going brittle.  But this will also depend strongly upon joint fitness, as the IM layer is only some microns thick normally.

Tim

[coppercone2]

the bridget is in the TDS
https://www.rsd.net/assets/prod/745.pdf

I am inclined to believe harris numbers because their only job is like to prevent stuff from breaking. I don't think they care about anything else lol

[coppercone2]

Lol what kind of results would just tugging on the wire give? I mean taking solder and seeing when it rips. maybe their just yanking it

but harris makes tons of welding shit. I assume they might use the same machines for testing welding and brazing and soldering because its cheaper. I don't think they are allowed to bullshit data like that for something like structural rod welding. But a pure electronics manufacturer.... hmmmm  can we trust them to buy a pull tester and actually solder a 1 inch area joint.. ?

I feel like if they specify both shear and tensile, that means it must be tested on some pretty specific setup. Tugging pipes apart is shear I think.

[coppercone2]

There is also this thing
https://xdevs.com/doc/_Materials/Chemistry/solder_alloy_directory_brochure_97720_r2.pdf


But its indium corp. I don't like them. I think they need to allow their employees to socialize because I swear they write all their stuff up so you have to give them a call. Perhaps they should do some company outings, give some PTO, because seriously they have
1) tons of critical information that is deleted from the website after I saw it there before, like something about a galium coated nickel felt
2) absolute crapshoot on what you can buy and what you need to call for
3) they wanna get to know your whole family before they will sell you some crap that you can make in a crucible. Or the nanofoils. But that is just w/e.. you could make something 100 times more potent with a god damn file and a old car (thermite). It's not nuclear ordinance.

I seriously think there is like a PR directive there that says "make every effort to confuse the customer so they contact us. make sure they need to contact the entire company leadership, and fill out paperwork, so they can join two random objects together". The other school of thought is that if something is easy to get, people talk about it, and it sells itself.


The only company more insane then them is that EMC place that wants your social security number to order metal stampings!!!!! You might get that from your boss if he smokes a fat crack rock before you ask him, because aint no one in america gonna give you that shit for a online order!!!!!!!!!!!

[Doctorandus_P]

You can use epoxy. It is mechanically quite strong and you don't have to heat it at all. It is however quite terrible at electrical connections 

Maybe you can use a combination. Solder the joints for the electrical connection, and use epoxy (or some other glue) for mechanical strength.

[T3sl4co1l]

Well, sure. Give or take creep.  But down at 1 mm^2 say, that's all of 8 lbf, or 40N say.  That's not much, I can pull that with one finger.

And maybe you want the safety factor to be 4, so it's barely enough to hold up, oh Idunno, a modest size transformer or something?  Factor could easily be 20 or more to account for mechanical shock.  Plus twisting/bending moment.  Clearly you'd want a stronger joint than that, and more contact points to distribute the load over.  Something like a PCB, doesn't have nearly as strong laminate/peel strength anyway, so you need quite a bit of soldering area, which is, well, how we normally do things, so there's that.

Anecdote: the bracing on my homebrew LED strip, that I have hanging over a closet door frame, started to look dangerously loose over the last couple of years; I finally took it down and redid the joints this year.  It was... how to put it, something of a tee joint, between two pieces of copper clad, one flat (base board), one perpendicular (the brace), with maybe a 5mm-long solder joint at the base on both sides.  The brace was subject to some leverage, as it sits at an angle; it was clearly pulling out of the solder joint and had displaced by several degrees.  This is over a good ten years or so, and fabbed with Sn63 solder.  I put it back up by doubling up on solder joints (the brace is resting against a cross-member that it previously wasn't soldered to), and adding another brace (a square to reinforce the cross-member from the backside, to prevent it bending).  At this rate, and given the reinforcements, it's probably good for 20 or 30 years, in which time the power supply, and probably current set of LEDs, will have long since expired.

Tim

[jonpaul]

I would not  depend  on  solder joint to hold mechanically,

It is only for electrical conduction.
 the conductors need to be fixed  independent  of the solder.

Eutectic has least crystalizaton and lowest MP.

63 /37 Tin/Lead.

j

[johansen]

Stay brite 8 has a tensile of 15,000 psi. Its just silver and tin.

[coppercone2]

Do you think the nickel might make it tougher or more resistant to creep with bridgit? Because nickel is tough as hell compared to tin and silver.  But they do say nickel is ductile.

Or the antimony. Antimony is hard and brittle. Does this bring down creep in an alloy? Can you make connections like that?

[T3sl4co1l]

Stay brite 8 has a tensile of 15,000 psi. Its just silver and tin.

Citation needed.

Horse mouth says 10.6 KSI,
https://ch-delivery.lincolnelectric.com/api/public/content/e521e75f45b741e58940da1988c2976d?v=a156575a
but again I'm dubious about method or how it's actually measured (no standard cited, and not that ASTM standards are generally publicly available anyway).

Indium Corp seems to suggest closer to 7,
https://www.matweb.com/search/DataSheet.aspx?MatGUID=19662ece2a4a4bb2bbe7aa522f916185
though the alloy is slightly different, but again, no mention of method.

Do you think the nickel might make it tougher or more resistant to creep with bridgit? Because nickel is tough as hell compared to tin and silver.  But they do say nickel is ductile.

Or the antimony. Antimony is hard and brittle. Does this bring down creep in an alloy? Can you make connections like that?

There's hardly any in it.  It's most likely present as a dispersion of microscopic particles.  These will frustrate slippage planes as any other hard inclusion, but in such small amount, mostly the solder will still slip around itself I think.  Think of forming pure clay, vs. forming clay with a few percent of coarse gravel in it, or marbles.  That's an imperfect analogy, because crystals have preferred slippage planes, whereas bulk clay is randomized (clay itself is lamellar, but only retains that grain when formed or deposited appropriately.)   Let's see... Ni3Sn4 seems to be the relevant intermetallic.  Very low solubility.  The other thing is it may act as a nucleation site for Sn grain growth, leading to finer crystal size, more grain boundaries, less weakness due to them; but this is a minor contribution I think.  The stuff like precipitation hardening in that other paper I found would do well, though still ultimately limited by strength of the matrix, and creepage mechanisms give or take.  I'd need to see more and better papers to have some idea what that ultimate strength might be.

Tim

[coppercone2]

The problem with hardly anything in alloys is that there are alloys that benefit from hardly anything. I.e. superalloys have ingredients added by 0.05%. They even have germanium doped solder for some reason... they call it doped. There is some PDF about it but I don't really understand much there, it looks like adding very small amounts of nickel halfs some problem parameter and then doping amount of germanium half it again.

I got the quartz crucible so I can try to make some of this stuff and test it. Easy enough to hang it on near overload with some weights. If I get around to it in the next 10 years

that is too much for me to understand with boundaries.

the expensive part appears to be the rolling machine for making wire. All the elements are pretty cheap apart from silver and gold. The machine looks like a 500 dollar investment at least But you can make square solder using a butchers knife and a body hammer I think

[Berni]

Regular leaded electronics solder might not be very strong compared to welding, but it can still hold a lot of force. Go ahead and solder two wires together and then try to pull them apart and see for yourself how strong solder can be.

Whatever bracket you are trying to solder on, just design the bracket in a way that it has a lot of surface area for the solder to flow between and grip onto. While you could improve strength by using stronger solder, you could easily make the existing solder hold 4x more force by simply giving it 4x more surface area to grab onto. That is likely a larger improvement than you would get from using some exotic low temperature solder.

[coppercone2]

its a heat exchanger so I need to be reasonable

[coppercone2]

https://link.springer.com/article/10.1007/s10854-023-10704-3

i wonder what else you can add

https://patents.google.com/patent/US4588657A/en
calcium

https://www.harrisproductsgroup.com/en/Products/hpg-na-sterling



selenium

[Coordonnée_chromatique]

Hello,
Consider the mechanical "strongness" of a metal by its tensile strength is like considering the power ability of a transistor by its case size only.

[David Hess]

For tin/lead solders, the common Sn62Pb36Ag2 alloy is suppose to be the strongest.

[johansen]

Stay brite 8 has a tensile of 15,000 psi. Its just silver and tin.

Citation needed.

Horse mouth says 10.6 KSI,

If you google "staybrite 8 tensile strength" you will find half a dozen sources whoch claim 14 or 15k psi, 10,500 shear.

https://www.firstsupply.com/Product/JWHSTABRITE

[T3sl4co1l]

If you google "staybrite 8 tensile strength" you will find half a dozen sources whoch claim 14 or 15k psi, 10,500 shear.

https://www.firstsupply.com/Product/JWHSTABRITE

Do you buy components based on what Mouser, Newark, etc. say in their catalogs?  Same thing: suppliers can be wrong, and often are.  Show me a datasheet -- otherwise it's just hearsay.

And again, no mention of creep, what rate this was measured at.

...Is this just a mechanical thing I don't know?  Are the acceptable standards for evidence just that much looser?  ...Do mechanical engineers science?

I know these things must exist, I see papers about them (if in short supply around this particular range of materials), and I know stuff like aerospace is, or at least can be, researched and simulated and evaluated to extreme degrees, so I don't seem to be asking anything facially unreasonable here.  This makes sense, right?

...Maybe it doesn't make sense, making such a big deal about the correctness of buddy it's just solder.  But then, that was the question, and if you're going to be fine with some random posting on the internet saying it's ca. 10KSI, I'll tell you this: you're equally well off knowing it's 5 or 20 -- all of them are equally wrong.

Tim

[coppercone2]

https://www.rsd.net/assets/prod/742.pdf

it says 14kpsi

[T3sl4co1l]

https://www.rsd.net/assets/prod/742.pdf

it says 14kpsi

[datasheet]
but again I'm dubious about method or how it's actually measured (no standard cited, and not that ASTM standards are generally publicly available anyway).

We're going in circles here.....

Tim

[coppercone2]

its not a random internet source it has harris letterhead on it. again I would be surprised if a primary welding supplier is not doing the tests the same way they test their other joints

[T3sl4co1l]

The source is fine (the sheet, not the supplier).  The content is not -- it's unsupported, a number in relation to nothing else.  If I try to sell you a computer speaker that claims "800W PMPO", are you not the least bit curious what method I applied to arrive at such a ridiculous number?

Only one thing left to do: contact them and inquire what their actual test methods are (and, why they don't put that in the datasheet).

Tim

[coppercone2]

My reasoning is unless there is deception they have some pulling machines to do lap joint tugging for weld rod testing. I suspect they solder two 1 inch area rods together end to end and put it in the machine. I have seen footage some where long ago of silver braze being tested this way, along with welded samples (they have 3-4 different machines with various adapters ETC if they need to test pulling two sheets apart), maybe even in harris. I suspect their technicians will do the same thing over and over again (as close as possible because they don't like changing anything in test labs nor do they like learning). The pull test for rods (i.e. welded rebars, girders) HAS to be good in a company like harris, because they have the certs for construction materials, even probobly bridges etc, which is serious shit. That is occams razor corporate for me.

Now if there is a sneaky salesman doing something else that would be disappointing. I think I have seen copper pipe maybe, for some hVAC testing videos, what they did there is solder two pipes together after one of em was expanded  bit on a mandrel, then attach it to a steel rod with alot of braze, and put it in the pull tester machine

[DiodeDipShit]

Berni has the issue solve.

[Berni]

Also as people above mentioned tensile strength is not the whole story. Once you expose things to a heavy vibration environment you might get a failure due to metal fatigue instead of over stress. Solder is prone to metal fatigue, exotic solder mixes might be even more so.

While designing a bracket to give more surface area to grab onto is pretty easy. Instead of just having a cut off end meet the object you give it a L shape to increase surface area contacting, perhaps add gussets add more area and prevent bending that might cause extra fatigue. Even better if you can design the brackets solder joint to be primarily loaded in sheer force rather than tensile force. If given enough surface area the copper bracket might break before the joint itself does (since copper itself is not a very strong material, also loves to fatigue crack).

Id say if any of that is still too weak, then you are approaching the problem from the wrong direction and need to use a steel bracket attached with a large number of strong high grade screws or something. (In that case id love to know what your product is going trough to have a heat ex changer exposed to such forces, since it sounds like that component is going for a very exiting ride)

[T3sl4co1l]

Huh, there's actually a Wikipedia article on it:
https://en.wikipedia.org/wiki/Solder_fatigue
only discusses the models though, no example parameters for alloys.

This seems interesting,
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4121147/
just scanning it, I don't see a discussion of fatigue limit (stress for number of cycles)...

Or this,
https://www.osti.gov/servlets/purl/1818047
preliminary, so presumably there's a follow-up reporting high-cycle data, hmm...

But yeah, needless to say, solder doesn't do well with static loads, or heavy vibration.  A certain amount of static strain, particularly at elevated temperature, can be relieved by creepage, but constant or repeated creepage eventually leads to crack formation.  High frequencies are better (more strength for given fatigue cycles), as suggested by the time dependency.  Which is again why single numbers don't mean a thing, sure it might be 15KSI, at what rate? Is that a shock load or what? Against what materials, what surface prep, what joint geometry?  All of these matter and the results can vary wildly.  And if you're trying to apply that number to some other geometry, how confident are you that that number will even apply?  A solder joint is not simply a solder joint!

Also, how much and in what ways strain relief happens, probably varies substantially with and without lead (at all, a few percent, ~half..).  And pure tin is known to relieve stress by whiskering; I haven't seen mention of that alongside this [bulk stress, fatigue] yet, but I wouldn't be surprised if that's part of it.  Annealed matte tin is the best to deal with whiskering, IIRC, which is to say, relieved stresses.

Like I said, if you need to fix something in place, using epoxy is likely to fare better; it is free from creepage AFAIK, and apparently can have exceptional fatigue limits (particularly composites like carbon fiber?).  Even if you need to make the joint bigger to handle a lower tensile or adhesion strength (say 1 or 2 KSI peak repetitive loading), as long as you have the area available, sure, slather it up eh?

Tim

[coppercone2]

IDK man for the same size epoxy and solder joint for something small I trust the solder way more

Like if you glue down a stud you can knock it off but a soldered one is damn strong

[DiodeDipShit]

The eternally revolving thread...... Solder fails pull test, take 12......
What is the hang weight of the application, times the pulse rate, times the duration of pull, times factors of solder adherence fatigue fracture, equals ultimate failure.
Is ultimate failure unacceptably shorter than life expectancy, then the drawing board must be revisited.
An angle will tear the joint imperceptibly at first, at the juncture of the right angle, but leading, in shorter time to a catastrophic failure.
Therefore the use of a channel bracket will distribute stress to two junctures, exponentially extending life expectancy.
This requires the use of a clevis pin spanning the opening of the channel and a sturdy eye bolt with a close tolerance engagement of the OD of the Clevis and ID of the eye.
Still, failure will occur given enough cycles of abuse. Has the soldered channel , clevis and eye exceeded life expectancy, so be it.
Has the channel fallen short? Add four bolts close within the the four corners of the channel, aligned with four tapped holes, twice deep of the internal thread diameter of the bolts, into the copper....... If this configuration fails life expectancy, place your head between your legs and kiss your azz goodby.

[jpanhalt]

Like if you glue down a stud you can knock it off but a soldered one is damn strong

I've never tried to solder a wood 2x4 stud.  What flux did you use?  Were you attaching directly to concrete or a wood base?

[T3sl4co1l]

Like if you glue down a stud you can knock it off but a soldered one is damn strong

I've never tried to solder a wood 2x4 stud.  What flux did you use?  Were you attaching directly to concrete or a wood base?

You must think you're such a hit with the ladies.

https://www.pemnet.com/products-overview/products-studs/

I assume something like this... hopefully with a wider base to distribute load better, and, obviously made for soldering.

On a related note, guess I should cross-link this thread as well: https://www.eevblog.com/forum/manufacture/mounting-a-pcb-using-only-surface-mount/

Tim

[jpanhalt]

Steel "studs" used in the USA are not intended for weight bearing and are intended to be screwed, not soldered.  But then, it's CC2, who knows?  Maybe a gallium alloy sticks well to wood studs, and that is what he used.

I have been with one woman for 56 years and have no intention of getting a newer version that can navigate for me.

[DiodeDipShit]

I believe Coppercone is referring to a circuit board terminal stud. . . . . . . See attached file.

[IanB]

I would not  depend  on  solder joint to hold mechanically,

It is only for electrical conduction.

Just because tin/lead solder is very convenient for electrical joins, does not mean it cannot also be used for mechanical joins. It has been used in plumbing applications forever, and still is (minus the lead). Try to pull a plumbing joint apart by force, and see if you can.

When I was young I used soft solder to join various steel parts together in projects, and they held together fine.

[johansen]

Put a lot of vias under anything mechanically surface mounted...

[T3sl4co1l]

Joke being, there's indeed three meanings: stud, the (usually wooden) beams making up walls in conventional wood-frame housing; stud, the threaded metal rod used for fixing things in place (ranging from all-thread e.g. studs in an engine block to weld-on elements used in fabrication, shipbuilding, etc.); and stud, male breeding stock.  Unsure of which one was meant, I chose the obviously-wrong third for hopeful comedic effect.

Tim

[mzzj]

I would not  depend  on  solder joint to hold mechanically,

It is only for electrical conduction.

Just because tin/lead solder is very convenient for electrical joins, does not mean it cannot also be used for mechanical joins. It has been used in plumbing applications forever, and still is (minus the lead). Try to pull a plumbing joint apart by force, and see if you can.

When I was young I used soft solder to join various steel parts together in projects, and they held together fine.

Even more extreme application would be typical double-barrel shotgun. Barrels are soldered to the breech block and have to withstand proof pressures up 20 000PSI.

Although it is known that with some shotguns the barrels start to escape if barrels get really hot during shooting.

[coppercone2]

I drilled and tapped it because I realized there is a place to do it

[tooki]

Joke being, there's indeed three meanings: stud, the (usually wooden) beams making up walls in conventional wood-frame housing; stud, the threaded metal rod used for fixing things in place (ranging from all-thread e.g. studs in an engine block to weld-on elements used in fabrication, shipbuilding, etc.); and stud, male breeding stock.  Unsure of which one was meant, I chose the obviously-wrong third for hopeful comedic effect.

Tim

Don't forget the studs punks and fancy fashion designers rivet to their clothes and accessories!

[T3sl4co1l]

Joke being, there's indeed three meanings: stud, the (usually wooden) beams making up walls in conventional wood-frame housing; stud, the threaded metal rod used for fixing things in place (ranging from all-thread e.g. studs in an engine block to weld-on elements used in fabrication, shipbuilding, etc.); and stud, male breeding stock.  Unsure of which one was meant, I chose the obviously-wrong third for hopeful comedic effect.

Tim

Don't forget the studs punks and fancy fashion designers rivet to their clothes and accessories!

I think even more generally, studs are metal attachments of some sort or another, but I should look up an actual definition at this point.

So there you have it, if they were made out of wood they might be all three at once.

Tim