Yes, that was the idea of option 4. Unfortunately, the the smallest solder pins are still larger than a 1mm hole, and a 1.00mm solid lead is a rather tight fit so I'm not confident about 1.02mm pins. If I go with a non-soldered option, very few terminals are under 1mm, Wago 233 series being about the only ones I find.
Yes, I'm using a 40VA transformer, which is still possibly more than I need for the intended preamp. The lead diameters are 0.97-1.04mm, a little tricky to get a perfectly round stranded cable once tinned.
Keep in mind that a stripboard trace is 1.90mm x 35u, so should have far less current capacity than a 0.785sqmm wire, though I accept that we should strengthen every weak link as possible.
I have some 0.81mm cutoffs which could do, but think I'll go with the drilling option. 1.2mm is large enough that to my eyes it takes just a bit too much trace away for my comfort. if I wallow around a little with a 1.0mm it get's there but is hard to control so as not to end up with a 1.2mm hole. I think I'll order 1.05mm & 1.1mm bits and have a go with those tomorrow.
BTW: in an effort to beef up some of the longer traces*, I've been thinking to solder bare wire along it's length (2-4 cm), but there are practical considerations. Soldering all along seems tricky to do without overheating the trace-strip and lifting it off.
I could solder only at each end and one point in the middle for stability. Is it safe to assume that the bare wire laying loosely on the strip is immune from some sort of electrical (or mechanically induced) noise since it is soldered at each end? Or I could just run insulated wire solder at the ends.
*Note post 21 on pg 3 about the difference between sqmm of hookup wire and stripboard traces.
I could solder only at each end and one point in the middle for stability. Is it safe to assume that the bare wire laying loosely on the strip is immune from some sort of electrical (or mechanically induced) noise since it is soldered at each end? Or I could just run insulated wire solder at the ends.
*Note post 21 on pg 3 about the difference between sqmm of hookup wire and stripboard traces.
Don't solder on wire to a trace. Except when trying to repair a trace that has blown off during an accident.
Your post21 mm conversions are not correct.
24awg is ~ 0.0201" diam, 0.511mm diam, 0.205sqmm
20awg is ~ 0.032" diam, 0.812mm diam, 0.518sqmm
But those are for solid core. A stranded wire that looks about the same diameter is likely to be much lower cross sectional area.
40VA with stranded leads should fit 1mm diameter holes. You're not trying hard enough.
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You say not to solder wire to a trace, but provide no information why. That info is needed.
Posts 21 & 42 are not about transformer leads or stranded cable. They are about solid core hookup wire as compared to standard stripboard traces. BTW: yes, the decimal points are missing on post 21, but otherwise correct. (By the time I noticed the typo error, it was too late to edit.)
From previous posts regarding termination of wiring [input / output], I read this advice to be based on the likelihood of mechanical stress loading [axial or radial thrust] of an unsupported wire lifting the trace... and consequential short circuit to adjacent traces.
The way to avoid this stress is to pass the wire through the board and then solder. If really concerned of movement through board or reduction in trace due to hole enlargement, bend wire to pass through hole and lay over trace where it solders.
Hookup wire is small cross sectional area = current capacity. The solder you use to bond the small wire probably has a higher CSA than the trace and pissant wire combined.
If I'm using 1.5mm2 or 2.5mm2 single strand wire to boost a trace I form a pin at both ends to pass through an enlarged hole both ends of the trace. These pins are trimmed down to < 1mm so they don't project through the board. This is only to assist location of wire when soldering, but such a wire projecting through the board could be made 5 to 8mm long and used like a wire wrap pin to solder a interconnect wire [input or output].
Due to my electrical trade background I size cables according to cross sectional area rather than an ambiguous 'gauge' or diameter.
From this a fair estimation of current caring capacity is easily determined, albeit highly de-rated due to such current ratings based on factors like insulation temperature [and length of cable of no relevance in a here due to short length and voltage drop within say an amplifier box].
e.g. 1mm2 is good for 10A, 1.5mm2 is good for 15A and 2.5mm2 is good for 25A. After that you have larger 4, 6, 10 16, 25, 35, 50 and higher standard cable CSA easily obtainable in a variety of insulation thermal ratings.
These common cable sizes [1 - 2.5mm2] came in both solid and stranded form.
So, I tend to solder terminate an output cable from a board and use screw terminal blocks for input terminations... all 'though hole' method.
When soldering terminating stranded wire to boards [through hole or at a screw clamp terminal] I always use wire ferrules [sometime referred to as 'bootlace'] that have an insulation sleeve. The sizes are colour coded and available as single or twin wire sleeve] This sleeve covers wire insulation so that if insulation creeps back due to use of dodgy strippers that stretch insulation in process of stripping over time or due to heating related shrinkage.... that would leave an unsupported or insulated conductor close to the board or terminal.
It also serves as a means of restricting axial thrust through the hole that lifts traces.
Seems few of folks here use these ferrules that are the minimum standard wire termination in Industry.
If you are worried about reduction in trace width from enlarging holes to accommodate a >1mm diameter pin or ferrule then use 2 traces at the location with soldered on copper foil where the wire or lug passes... or a ring formed on the wire you use to boost CSA [and so current capacity] of the trace you solder on.
Can't say I like 'quickon' terminals much at all.
I've seen too many failures in-service. if they start to heat from loose connection it's downhill all the way.
Unless dual later boards are used for the soldered lug, the same mechanical stress can effect trace lifting when wire lugs are pushed on or lifted off. I wouldn't rely on tight fit through a bakelite or even fiberglass pcb board to ensure low risk of trace lifting through movement... enough stress loading can deform any hole they pass through.
Tight connections between wire lug and solder spade are dependent upon the spring tension of the material the lug is made of [sometimes brass and sometimes plated copper].
I've seen many a mains voltage wiring connection in appliances like washing machines or even ovens heat fail due to weak spring action of the lugs or deform due to frequent connection/disconnection. Same situation in automotive applications that are also subject to vibration effects.
They may be 'convenient' and 'quick' in a mass production environment, but how often do you need to connect and disconnect these cable connections in your electronic projects?
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Thank you "Shhh its me", useful information, all. I'll consider how this info might influence.
Though it is popular on this forum to build with PCB spades and push on connections, I don't really trust them, either, for long term, efficient, reliable, connections. Seems to me odd to put all the effort and consideration into implementing a better circuit and then trust the connections to push-on friction-fit terminals.
Since I perhaps wasn't clear, my discussion of wire cross sections was meant to be comparing resistance & current capacity to that of thin traces, and improving the traces by a parallel run of wire solid core hookup wire which has 4-8 times more CSA than the trace. It was meant to be a completely different discussion from wires/pins fitting through stripboard holes from my traffo leads.
Though it is popular on this forum to build with PCB spades and push on connections, I don't really trust them, either, for long term, efficient, reliable, connections. Seems to me odd to put all the effort and consideration into implementing a better circuit and then trust the connections to push-on friction-fit terminals.
Since I perhaps wasn't clear, my discussion of wire cross sections was meant to be comparing resistance & current capacity to that of thin traces, and improving the traces by a parallel run of wire solid core hookup wire which has 4-8 times more CSA than the trace. It was meant to be a completely different discussion from wires/pins fitting through stripboard holes from my traffo leads.
No worries, it was a bit of a 'catch all' of a few issues that presented over the last postings.
I just hope it was clear, especially the use of ferrules for decent termination of stranded cables.
I relation to bolstering traces as you question, I can't see an issue at all. I assume we all add a layer of solder along used traces to be sure,... I tend to remove traces not used and do so to increase tracking clearance between traces when voltages get above 'extra-low voltage' level. ie > 36V
As for CSA of wire used.... low csa for low current [hookup size] and 1mm2 to 2.5mm2 according to the maximum current expected. I suggest no problem in exceeding such a maximum demand.
I have virtually unlimited access to stranding derived from power cables and so, variety in diameters/CSA. Only problem with strands from modern 'compact stranded' cable is that due to to close packing of strands [7 strands in a 16mm2 cable] the individual strands are not round... they have a distorted profile after being squished together, that can be inconsistent along a length. These strands, due to work hardening during manufacture, being harder than single strand wire that still has a degree of annealing.
I've also a stockpile of much older cable reclaimed from house rewires. This has been the nasty old 1950's style VIR [Vitrified Indian Rubber] insulated cable. The single core wire strand is always tin plated in such cable... making it rather convenient for this bolstering.
I've also used thin copper foil sheet, cut to shape and width to suit spanning multiple traces. I clean and pre tin this before applying to the pcb traces that have also been generously tinned. Gets fiddly. I drill out any through holes for components and terminations following application. The copper foil is relatively thin compared to solder between the much thinner copper trace on the board.
I drill open holes or locate where I want using 0.8mm, 1.0mm, 1.5mm, 2mm 2.5mm drill bits in a manual pin vice rather than set up the high speed Dremel tool. They drill easy enough through existing pcb holes and enlarge from the copper side just as easy, be it bakelite or fiberglass.
The only traces I have lift, due to excessive temp generally, are those on bakelite boards. Bolsterd traces never seem to threaten to lift even with harsh enlargement of holes. Just use sharp drills that require little pressure to cut.
I just hope it was clear, especially the use of ferrules for decent termination of stranded cables.
I relation to bolstering traces as you question, I can't see an issue at all. I assume we all add a layer of solder along used traces to be sure,... I tend to remove traces not used and do so to increase tracking clearance between traces when voltages get above 'extra-low voltage' level. ie > 36V
As for CSA of wire used.... low csa for low current [hookup size] and 1mm2 to 2.5mm2 according to the maximum current expected. I suggest no problem in exceeding such a maximum demand.
I have virtually unlimited access to stranding derived from power cables and so, variety in diameters/CSA. Only problem with strands from modern 'compact stranded' cable is that due to to close packing of strands [7 strands in a 16mm2 cable] the individual strands are not round... they have a distorted profile after being squished together, that can be inconsistent along a length. These strands, due to work hardening during manufacture, being harder than single strand wire that still has a degree of annealing.
I've also a stockpile of much older cable reclaimed from house rewires. This has been the nasty old 1950's style VIR [Vitrified Indian Rubber] insulated cable. The single core wire strand is always tin plated in such cable... making it rather convenient for this bolstering.
I've also used thin copper foil sheet, cut to shape and width to suit spanning multiple traces. I clean and pre tin this before applying to the pcb traces that have also been generously tinned. Gets fiddly. I drill out any through holes for components and terminations following application. The copper foil is relatively thin compared to solder between the much thinner copper trace on the board.
I drill open holes or locate where I want using 0.8mm, 1.0mm, 1.5mm, 2mm 2.5mm drill bits in a manual pin vice rather than set up the high speed Dremel tool. They drill easy enough through existing pcb holes and enlarge from the copper side just as easy, be it bakelite or fiberglass.
The only traces I have lift, due to excessive temp generally, are those on bakelite boards. Bolsterd traces never seem to threaten to lift even with harsh enlargement of holes. Just use sharp drills that require little pressure to cut.
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