Physical and Mechanical Properties of Solder Alloys
Original source: http://alasir.com/reference/solder_alloys/
Solder Alloy | Melting Point, °C solidus / liquidus |
Density, g/cm³ |
Electrical Resistivity, µΩ⋅m |
Thermal Conductivity, W/m⋅K |
Tensile Strength at Break, kgf/cm² |
Tensile Elongation at Break, % |
Brinell Hardness, HB |
alloys of tin (Sn) with silver (Ag) and / or copper (Cu) | |||||||
Sn96.5Ag3.5 (alloy #121) |
221 / 221 | 7.37 | 0.123 | 55 | 580 | 35 | 15 |
Sn95Ag05 (alloy #132) |
221 / 240 | 7.40 | 0.137 | - | 565 | 30 | 14 |
Sn90Ag10 (alloy #156) |
221 / 295 | 7.51 | - | - | - | - | - |
Sn99.3Cu0.7 (alloy #244) |
227 / 227 | 7.31 | 0.126 | 66 | 300 | 21 | 9 |
Sn97Cu03 (alloy #160) |
227 / 300 | 7.32 | 0.118 | - | - | - | - |
Sn99.2Ag0.1Cu0.7 (SAC0107) |
217 / 228 | 7.32 | - | - | - | - | - |
Sn99Ag0.3Cu0.7 (alloy #263 or SAC0307) |
217 / 228 | 7.33 | - | - | 300 | 22 | 14 |
Sn98.5Ag0.8Cu0.7 (SAC0807) |
216 / 225 | 7.33 | 0.140 | - | 310 | 21 | 16 |
Sn98.5Ag1.0Cu0.5 (alloy #258 or SAC105) |
215 / 227 | 7.32 | 0.133 | 60 | 400 | 13 | 13 |
Sn97.1Ag2.6Cu0.3 (SAC263) |
217 / 224 | 7.36 | 0.132 | - | - | - | - |
Sn96.5Ag3.0Cu0.5a (alloy #256 or SAC305) |
217 / 220 | 7.38 | 0.132 | 58 | 500 | 19 | 15 |
Sn95.5Ag4.0Cu0.5 (alloy #246 or SAC405) |
217 / 220 | 7.44 | 0.132 | 62 | 530 | 17 | 15 |
Sn95.5Ag3.8Cu0.7b (alloy #241 or SAC387) |
217 / 220 | 7.44 | 0.132 | 60 | 600 | 16 | 15 |
alloys of tin (Sn) and lead (Pb) with or without silver (Ag) | |||||||
Sn90Pb10 (alloy #118) |
183 / 213 | 7.55 | - | - | 490 | 40 | - |
Sn63Pb37 (alloy #106) |
183 / 183 | 8.40 | 0.145 | 50 | 525 | 37 | 17 |
Sn62.5Pb36.1Ag1.4 (alloy #104) |
179 / 179 | 8.41 | 0.145 | 50 | 490 | - | 16 |
Sn60Pb40 (alloy #109) |
183 / 191 | 8.50 | 0.153 | 49 | 535 | 40 | 16 |
Sn55Pb45 (alloy #113) |
183 / 200 | 8.68 | - | - | - | - | - |
Sn50Pb50 or Pb50Sn50 (alloy #116) |
183 / 212 | 8.87 | 0.158 | 48 | 420 | 35 | 14 |
Pb55Sn45 or Sn45Pb55 (alloy #125) |
183 / 227 | 9.07 | 0.166 | - | - | - | - |
Pb60Sn40 or Sn40Pb60 (alloy #130) |
183 / 238 | 9.28 | 0.171 | 44 | 380 | 25 | 12 |
Pb65Sn35 or Sn35Pb65 (alloy #135) |
183 / 247 | 9.50 | 0.176 | - | - | - | 12 |
Pb70Sn30 or Sn30Pb70 (alloy #141) |
183 / 257 | 9.72 | 0.185 | 41 | 350 | 18 | 12 |
Pb75Sn25 or Sn25Pb75 (alloy #145) |
183 / 268 | 9.96 | 0.194 | - | 240 | 53 | 11 |
Pb80Sn20 or Sn20Pb80 (alloy #149) |
183 / 280 | 10.21 | 0.198 | 37 | 340 | 20 | 11 |
Pb85Sn15 or Sn15Pb85 (alloy #153) |
183 / 288 | 10.70 | - | - | 330 | - | 11 |
Pb88Sn10Ag02 (alloy #228) |
267 / 290 | 10.75 | 0.203 | 27 | 230 | 42 | - |
Pb90Sn10 or Sn10Pb90 (alloy #159) |
275 / 302 | 10.75 | 0.194 | 25 | 310 | 30 | 10 |
Pb92.5Sn05Ag2.5 (alloy #151) |
287 / 296 | 11.02 | 0.200 | - | 295 | - | - |
Pb95Sn05 or Sn05Pb95 (alloy #171) |
308 / 312 | 11.06 | 0.196 | 23 | 280 | 45 | 8 |
Pb97.5Ag1.5Sn01 (alloy #165) |
309 / 309 | 11.28 | 0.287 | 23 | 310 | 23 | 9 |
alloys of bismuth (Bi) and / or cadmium (Ca) with tin (Sb) and / or lead (Pb) | |||||||
Bi58Sn42 (alloy #281) |
138 / 138 | 8.56 | 0.383 | 19 | 565 | 55 | 23 |
Sn60Bi40 (alloy #281-338) |
138 / 170 | 8.12 | 0.345 | 30 | 525 | 35 | 24 |
Bi55.5Pb44.5 (alloy #255) |
124 / 124 | 10.44 | 0.431 | 4 | 450 | 38 | 15 |
Sn43Pb43Bi14 (alloy #97) |
144 / 163 | 9.02 | - | - | 450 | 41 | - |
Sn51.2Pb30.6Cd18.2 (alloy #181) |
145 / 145 | 8.45 | - | 35 | 440 | - | - |
alloys of indium (In) with lead (Pb) and / or tin (Sn) and / or silver (Ag) | |||||||
In70Pb30 (alloy #204) |
165 / 175 | 8.19 | 0.196 | 38 | 245 | - | - |
In60Pb40 (alloy #205) |
173 / 181 | 8.52 | 0.246 | 29 | 290 | - | - |
In50Pb50 or Pb50In50 (alloy #7) |
184 / 210 | 8.86 | 0.287 | 22 | 330 | 55 | 10 |
Pb60In40 (alloy #206) |
197 / 231 | 9.30 | 0.332 | 19 | 350 | - | - |
Pb75In25 (alloy #10) |
240 / 260 | 9.97 | 0.375 | 18 | 385 | 48 | 10 |
Pb81In19 (alloy #150) |
260 / 275 | 10.27 | 0.383 | 17 | 390 | - | - |
Pb95In05 (alloy #11) |
300 / 313 | 11.06 | 0.338 | 21 | 305 | 52 | 6 |
In52Sn48 (alloy #1E) |
118 / 118 | 7.30 | 0.147 | 34 | 120 | 83 | 5 |
In50Sn50 or Sn50In50 (alloy #1) |
118 / 125 | 7.30 | 0.147 | 34 | 120 | 83 | 5 |
In97Ag03 (alloy #290) |
143 / 143 | 7.38 | 0.075 | 73 | 55 | - | 2 |
In90Ag10 (alloy #3) |
143 / 237 | 7.54 | 0.078 | 67 | 115 | 61 | 3 |
In80Pb15Ag05 (alloy #2) |
149 / 154 | 7.85 | 0.133 | 43 | 180 | 58 | 5 |
Pb90In05Ag05 (alloy #12) |
290 / 310 | 11.00 | 0.308 | 25 | 405 | 23 | 9 |
Pb92.5In05Ag2.5 (alloy #164) |
300 / 310 | 11.02 | 0.313 | 25 | 320 | - | - |
Sn77.2In20Ag2.8 (alloy #227) |
175 / 187 | 7.25 | 0.176 | 54 | 480 | 47 | 17 |
Sn37.5Pb37.5In25 (alloy #5) |
134 / 181 | 8.42 | 0.221 | 23 | 370 | 101 | 10 |
Sn54Pb26In20 (alloy #230) |
136 / 152 | 8.05 | - | - | - | - | - |
Sn70Pb18In12 (alloy #9) |
154 / 167 | 7.79 | 0.141 | 45 | 375 | 136 | 12 |
low temperature alloys | |||||||
In51.0Bi32.5Sn16.5 (alloy #19 or Field's alloy) |
60 / 60 | 7.88 | 0.522 | - | 340 | - | 11 |
Bi50Pb26.7Sn13.3Cd10 (alloy #158 or Wood's alloy) |
70 / 70 | 9.58 | 0.431 | 18 | 420 | 120 | 15 |
Bi52Pb30Sn18 (alloy #39 or Newton's alloy) |
96 / 96 | 9.60 | 0.750 | 13 | 365 | 100 | 16 |
Bi50Pb28Sn22 (alloy #41 or Rose's alloy) |
100 / 100 | 9.44 | - | - | - | - | - |
other alloys | |||||||
Sn95Sb05 (alloy #133) |
235 / 240 | 7.25 | 0.145 | 28 | 415 | 38 | 13 |
Sn91Zn09 (alloy #201) |
199 / 199 | 7.27 | 0.115 | 61 | 560 | 33 | 22 |
Au80Sn20 (alloy #182 or Orotin) |
280 / 280 | 14.51 | - | 57 | 2800 | 2 | - |
Au88Ge12 (alloy #183 or Georo) |
356 / 356 | 14.67 | - | - | 2150 | 1 | - |
Pb97.5Ag2.5 (alloy #161) |
303 / 303 | 11.33 | 0.200 | - | 310 | 42 | - |
Pb94.5Ag5.5 (alloy #229) |
304 / 365 | 11.35 | 0.287 | 23 | 310 | - | - |
Pb85Sb10Sn05 (alloy #233) |
245 / 255 | 10.36 | 0.287 | - | 390 | 4 | - |
In100 (pure indium) |
157 / 157 | 7.31 | 0.0837 | 86 | 20 | - | 1 |
Sn100 (pure tin) |
232 / 232 | 7.29 | 0.124 | 73 | 135 | - | 4 |
Bi100 (pure bismuth) |
271 / 271 | 9.78 | 1.29 | 8 | - | - | 7 |
Pb100 (pure lead) |
327 / 327 | 11.34 | 0.218 | 35 | 125 | 55 | 4 |
Ag100 (pure silver) |
960 / 960 | 10.49 | 0.0163 | 429 | 1480 | 50 | 25 |
Au100 (pure gold) |
1064 / 1064 | 19.30 | 0.0221 | 318 | 1405 | 42 | 25 |
Cu100 (pure copper) |
1085 / 1085 | 8.94 | 0.0172 | 401 | 2460 | 40 | 35 |
a) U.S. patent #5527628 issued on the 18-June-1996 to SMIC (Senju Metal Industry Co.), will expire internationally on the 24-Feb-2015;
b) U.S. patent #4929423 issued on the 29-May-1990 to Cookson Group, expired internationally on the 31-Mar-2009;
NOTES:
1. Electrical resistivity and thermal conductivity are evaluated usually at 20°C and 85°C respectively.
2. Electrical resistivity is inverse to electrical conductivity.
3. Electrical conductivity is often expressed in % IACS which stands for International Annealed Copper Standard.
100% IACS is electrical conductivity of annealed copper which equals to 58.0 × 106 S⋅m-1.
4. Tensile strength in kgf/cm² may be converted to psi (pounds per square inch) by multiplying with 14.22.
NOTES:
1. Electrical resistivity and thermal conductivity are evaluated usually at 20°C and 85°C respectively.
2. Electrical resistivity is inverse to electrical conductivity.
3. Electrical conductivity is often expressed in % IACS which stands for International Annealed Copper Standard.
100% IACS is electrical conductivity of annealed copper which equals to 58.0 × 106 S⋅m-1.
4. Tensile strength in kgf/cm² may be converted to psi (pounds per square inch) by multiplying with 14.22.
very useful, thank you!
Can you send me a 250g sample of the AU88GE12
[Reviews] Miboxer C4-12, C2-4k+6k, C2, C4 / Astrolux K1, MF01, MF02, S42, K01, TI3A / BLF Q8 / Kalrus G35, XT11GT / Nitefox UT20 / Niwalker BK-FA30S / Sofirn SF36, SP35 / Imalent DM21TW / Wuben I333 / Ravemen PR1200 / CL06 lantern / Xanes headlamp
[Mods] Skilhunt H03 short / Klarus XT11GT, XT12GTS / Zebralight SC50+ / Imalent DM21TW / colorful anodisation
[Sale]
Drivers: overview of sizes and types
DD+AMC based drivers Anduril or Bistro OTSM 12-24mm, S42, 24-30mm L6, Q8, MF01(S), MT03, TN42
Anduril or Bistro 8A buck driver for 20-30mm, MF01/02/04, TN40/42, Lumintop GT, MT09R
UVC and UVC+UVA drivers
programming key
Remote switch tail DD board with FET
Aux boards:
Emisar D1, D1S, D4, D4S, D18, Lumintop FW3A, Fireflies ROT66, Astrolux MF01, Tail boards like S2+
LOL, actually I’m wondering what’s its real world uses.
www.virence.com
Physical and thermal properties of solder alloy - Shooting Beamshots With HDR - Nichia E21A Tint Shots
Its Okay To Be Smart - SmarterEveryDay - Deep Look - Veritasium - Tech Ingredients
So to maximize thermal conductivity for overdriving emitters one should use pure Indium or Tin?
I suspect using pure Silver, Copper or Gold will fry the emitter
The Journal of Alternative Facts TM
"It is critical that there is a credible academic source for the growing and important discipline of alternative facts. This field of study will just keep winning, and we knew that all the best people would want to be on board. There is a real risk in the world today that people might be getting their information about science from actual scientists"
The question will be: is it worth the money spend/lumen gain?
Depends on intended applications. Pure Indium fluxless wire price is very expensive USD 95/3 ft.
www.virence.com
Physical and thermal properties of solder alloy - Shooting Beamshots With HDR - Nichia E21A Tint Shots
Its Okay To Be Smart - SmarterEveryDay - Deep Look - Veritasium - Tech Ingredients
I do not know on either count, but pure Tin may be a decent compromise
The Journal of Alternative Facts TM
"It is critical that there is a credible academic source for the growing and important discipline of alternative facts. This field of study will just keep winning, and we knew that all the best people would want to be on board. There is a real risk in the world today that people might be getting their information about science from actual scientists"
Pure Indium is very good as a thermo safety switch off
. You overdrive the LED and beyond 157C it fell off the MCPCB
Good only for low temp application. Any metals usually annealed far below their melting point. For example, SAC305 (Sn96,5Ag3Cu0,5) starts to anneal at 125C. TIM made from pure Indium also exhibit extremely soft physical characteristic, too soft for solder application hence the additives.
Pure Tin while has much higher melting point at 232C is not much harder than Indium. You can slice it with razor easily.
I often use the BiSn solder for super low temp soldering. Don’t really know the composition. It melts slightly below the PVC melting temp, used as convenient waterproof wire joiner.
www.virence.com
Physical and thermal properties of solder alloy - Shooting Beamshots With HDR - Nichia E21A Tint Shots
Its Okay To Be Smart - SmarterEveryDay - Deep Look - Veritasium - Tech Ingredients
Sorry to “necro” this thread, but I am hoping to find some information.
This week I bought a seringe of solder paste: Sn96,5Ag3Cu0,5 . This is the paste I bought:
https://www.tme.eu/gb/details/esac305_40/solders-other-lead-free/ag-term...
This my first time using solder paste, and I am no expert on this (or anything else!).
I will use this paste mainly to reflow some emitters that I will get soon.
I started practising on some older MCPCBs and with some old leds (just to test the “melting point”), and I noticed that it didn’t “melt” as good as my solder wire.
It started melting but then it became a sort of past with lots of tiny blobs that didn’t melt and that were a bit sticky
As I don’t have any tool or appropriate platform to make the reflow, I used my electrical stove, put the MCPCBs with the solder and waited for it to melt with time. It never reached that point and what happened was just what I described above…
So, my questions are,
How do we use this solder paste to get it to melt well to reflow the emitters?
How long does it normally take to melt?
What precautions must be taken?
What temperature should the stove reach to make it melt?
Last but not least, should I buy/use other type of solder to reflow, given the conditions I have (stove / lighter / soldering iron)?
I am sorry these are some questions I would like to see answered if possible.
Also, if anyone can point me to a video reflowing with this specific paste, that would be nice, as I searched but couldn’t find one.
BTW, here are the photos of the sh**y work I did

Thanks in advance!!
MY REVIEWS THREAD /// My Flashlight Collection ///
Mods: 1 / 2 // TIR: 1 / 2 // Others: Biscotti 3 + 1*7135 / Triple TIR w/ XP-G2 /// My Review's Blog (PT) /// OL Contest 2019 /// OL Contest 2020 /// GIVEAWAYs: 1 / 2
Either you need more heat or the flux is shit burning up before it bonds the solder balls together
Never seen such bad stuff, even with the cheap Chinese paste
You may try some more flux that does not burn, but I guess that paste does not work
To keep the LEDs in safe max temp go for leaded solder paste it behaves a lot better
[Reviews] Miboxer C4-12, C2-4k+6k, C2, C4 / Astrolux K1, MF01, MF02, S42, K01, TI3A / BLF Q8 / Kalrus G35, XT11GT / Nitefox UT20 / Niwalker BK-FA30S / Sofirn SF36, SP35 / Imalent DM21TW / Wuben I333 / Ravemen PR1200 / CL06 lantern / Xanes headlamp
[Mods] Skilhunt H03 short / Klarus XT11GT, XT12GTS / Zebralight SC50+ / Imalent DM21TW / colorful anodisation
[Sale]
Drivers: overview of sizes and types
DD+AMC based drivers Anduril or Bistro OTSM 12-24mm, S42, 24-30mm L6, Q8, MF01(S), MT03, TN42
Anduril or Bistro 8A buck driver for 20-30mm, MF01/02/04, TN40/42, Lumintop GT, MT09R
UVC and UVC+UVA drivers
programming key
Remote switch tail DD board with FET
Aux boards:
Emisar D1, D1S, D4, D4S, D18, Lumintop FW3A, Fireflies ROT66, Astrolux MF01, Tail boards like S2+
Thanks for your reply Lexel!
Hum, I just tried different approaches (heating the stove before putting the plate, progressively heating the stove, using some piece of copper below the pcb to maintain the heat so that it didn’t have a break…) and all failed. I guess that adding flux wouldn’t be any good too in this case
The blobs never cease to exist in any situation…
It seems that this is indeed a bad solder paste
Solder paste is hard to find in national stores, and those that have them are sold out
Ali and Ebay are full of fake stuff.
What could be a “good” product to use for reflowing leaded or non leaded?
MY REVIEWS THREAD /// My Flashlight Collection ///
Mods: 1 / 2 // TIR: 1 / 2 // Others: Biscotti 3 + 1*7135 / Triple TIR w/ XP-G2 /// My Review's Blog (PT) /// OL Contest 2019 /// OL Contest 2020 /// GIVEAWAYs: 1 / 2
MascaratumB,
While looking for Mechanic “XG-50” solder paste jars, it happens that I found this Karmor Tools store advertisement where Sn42Bi58, Sn63Pb37 and Sn96.5Ag3Cu0.5 solder pastes are sold. Nothing really wrong there, except that…
… a whopping 260 °C is claimed as Sn96.5Ag3Cu0.5's melting point. You need to raise the MCPCB temp above the melting point figure, and keep it above while you reflow. As a rule I manage to get any job done without exceeding +35 °C above solder melting point, which is less than 220 °C for Sn63Pb37 (183 °C melting point).
SN96.5Ag3Cu0.5 is probably a paste with too high melting point for reflowing leds. Standard Sn63Pb37 is cheap, good and beautiful:
I myself am very happy with “Mechanic” Sn63Pb37 solder paste.
Hope this is of help.
Sun, 03/29/2020 - 05:39; Sun, 03/29/2020 - 08:10
Deleting a just published post causes the forum thread answer notification to fail. Thus, if you need to change your just published post, edit it. Thanks.
Please avoid fully quoting lenghty posts, namely with nested quotes. Trim quotes down to the essential. Helps with neatness and legibility. Thanks.
- Yeah, but is it ultra high CRI?

I have used some good paste in the beginning I had from an old work
Since 2 years I use the cheap leaded Chinese paste, it has its flaws not liking any pressure like in a syringe with small hole or repeatedly used over a stencil in small quantity, it gets harder fast
Its so cheap I don’t hesitate to likely have to trash half of it, just put used in an old 50g container
Always pushing small fresh amounts out of the syringe with no tip or needle
Anyways unless you use a stencil I would always apply solder wire and some Amtech flux, the Chinese Amtech copy is as good as the original
Then moving the emitter around to make sure it wets everywhere
Then give dome a light tap to push out uneven/too much solder
[Reviews] Miboxer C4-12, C2-4k+6k, C2, C4 / Astrolux K1, MF01, MF02, S42, K01, TI3A / BLF Q8 / Kalrus G35, XT11GT / Nitefox UT20 / Niwalker BK-FA30S / Sofirn SF36, SP35 / Imalent DM21TW / Wuben I333 / Ravemen PR1200 / CL06 lantern / Xanes headlamp
[Mods] Skilhunt H03 short / Klarus XT11GT, XT12GTS / Zebralight SC50+ / Imalent DM21TW / colorful anodisation
[Sale]
Drivers: overview of sizes and types
DD+AMC based drivers Anduril or Bistro OTSM 12-24mm, S42, 24-30mm L6, Q8, MF01(S), MT03, TN42
Anduril or Bistro 8A buck driver for 20-30mm, MF01/02/04, TN40/42, Lumintop GT, MT09R
UVC and UVC+UVA drivers
programming key
Remote switch tail DD board with FET
Aux boards:
Emisar D1, D1S, D4, D4S, D18, Lumintop FW3A, Fireflies ROT66, Astrolux MF01, Tail boards like S2+
I made a video here, those LEDs were scrap that someone soldered with lead free solder too hot, problem is they did not soak themselves to the pads as the lead free was not at its melting point before mixing with leaded one
usually when flux added new LEDs pretty much jump to a center position as they wet then very good
generally I top off at about 200°C with solder wire, above 195°C it flows very good
[Reviews] Miboxer C4-12, C2-4k+6k, C2, C4 / Astrolux K1, MF01, MF02, S42, K01, TI3A / BLF Q8 / Kalrus G35, XT11GT / Nitefox UT20 / Niwalker BK-FA30S / Sofirn SF36, SP35 / Imalent DM21TW / Wuben I333 / Ravemen PR1200 / CL06 lantern / Xanes headlamp
[Mods] Skilhunt H03 short / Klarus XT11GT, XT12GTS / Zebralight SC50+ / Imalent DM21TW / colorful anodisation
[Sale]
Drivers: overview of sizes and types
DD+AMC based drivers Anduril or Bistro OTSM 12-24mm, S42, 24-30mm L6, Q8, MF01(S), MT03, TN42
Anduril or Bistro 8A buck driver for 20-30mm, MF01/02/04, TN40/42, Lumintop GT, MT09R
UVC and UVC+UVA drivers
programming key
Remote switch tail DD board with FET
Aux boards:
Emisar D1, D1S, D4, D4S, D18, Lumintop FW3A, Fireflies ROT66, Astrolux MF01, Tail boards like S2+
thank you for posting the video, that is a great camera arrangement to show both views.
i’ve never used paste or lead-free solder so have a question about the process.
Usually when soldering i first apply flux to the surfaces, then heat and touch the solder wire to “tin” the items, or to make the joint to connect a part to a pad.
It appears that flux was added as the final step in the paste/floating process. Is this due to mixing leaded and lead-free solder, or is this typically the way it is done?
Now i used to think that i was cool,
drivin' around on fossil fuel,
until i saw what i was doin',
was drivin' down the road to ruin. --JT
Thanks very much for your reply and help and for your video Lexel, it was really helpful!
I normally don’t use solder flux because the wire I have melts well, but for the reflows I guess I will have to get some.
About the paste, I’ve been reading and receiving some other suggestions about the quality of the paste, and as I am not soldering so frequently, I will probably try to get some better paste that can last for a while, so that I don’t waste many.
One thing I noticed was that your plate was slowly heating and the solder went melting evenly.
Seeing that, I and not sure if the process/method I did was the ideal one. I will have to try again to see how it works if I heat it slowly (with lower temperatures).
I am also takiung note of the solder composition to see what I can get locally. Some stores are pretty expensive in terms of shipping and many of them either don’t have the produts I am looking for, or ther are, eventually, fake!
Again, thank you very much for the help!
Thanks for noticing that too Barkuti!
I start to see that the composition will, indeed, have some troubles to me, so I may opt for other type of solder!
Thanks you too
…..
A noob like me surelly has a lot to learn from you folks!!!
MY REVIEWS THREAD /// My Flashlight Collection ///
Mods: 1 / 2 // TIR: 1 / 2 // Others: Biscotti 3 + 1*7135 / Triple TIR w/ XP-G2 /// My Review's Blog (PT) /// OL Contest 2019 /// OL Contest 2020 /// GIVEAWAYs: 1 / 2
LoL I wrote SN96.5Ag3Cu0.5 is probably a “too hot” thermal paste…
Edited it, paste with too high melting point for reflowing leds sounds better.
MascaratumB, I recommend you to get some standard “Mechanic” Sn63Pb37 solder paste besides any other stuff. True, tried and tested classic recipe, works pretty good imho. It is cheap, so you can practice plenty with the paste thing. Best if stored in some fridge, and take proper care of it.
Deleting a just published post causes the forum thread answer notification to fail. Thus, if you need to change your just published post, edit it. Thanks.
Please avoid fully quoting lenghty posts, namely with nested quotes. Trim quotes down to the essential. Helps with neatness and legibility. Thanks.
- Yeah, but is it ultra high CRI?

Solder paste has a shelf life of like 6-12 months at 7°C, if you use not it often go ahead and buy cheap Chinese mechanic paste, if it gets worse buy new one for like 2 pounds
Rosin core flux tends to oxidase when it’s a longer time hot
The Amtech (fake) flux not, but adding it as final step likely gives the best result
As I wrote the LEds were used and full of lead free solder on the pads, so they behaved not like new LEDs which would likely soak themselves easily on the pads even without additional flux added
Basically adding flux always makes the result better, so you cant overdo it
[Reviews] Miboxer C4-12, C2-4k+6k, C2, C4 / Astrolux K1, MF01, MF02, S42, K01, TI3A / BLF Q8 / Kalrus G35, XT11GT / Nitefox UT20 / Niwalker BK-FA30S / Sofirn SF36, SP35 / Imalent DM21TW / Wuben I333 / Ravemen PR1200 / CL06 lantern / Xanes headlamp
[Mods] Skilhunt H03 short / Klarus XT11GT, XT12GTS / Zebralight SC50+ / Imalent DM21TW / colorful anodisation
[Sale]
Drivers: overview of sizes and types
DD+AMC based drivers Anduril or Bistro OTSM 12-24mm, S42, 24-30mm L6, Q8, MF01(S), MT03, TN42
Anduril or Bistro 8A buck driver for 20-30mm, MF01/02/04, TN40/42, Lumintop GT, MT09R
UVC and UVC+UVA drivers
programming key
Remote switch tail DD board with FET
Aux boards:
Emisar D1, D1S, D4, D4S, D18, Lumintop FW3A, Fireflies ROT66, Astrolux MF01, Tail boards like S2+
Balling occurs most certainly with too fast heating. Soaking in 100°C for a minute or two will greatly reduce balling. Other cause is the expired, dried, or deactivated flux. You can reuse dried paste by adding thin flux to it. SAC305 requires a bit longer soaking than 63/37.
The other important thing is post reflow heating. Rather than 260°C I prefer to post reflow at 240°C for 2 minutes to make sure all solder granules diffused to each other completely. This is very important with gold plated pads to make sure all gold diffused as much as possible. In many cases, not enough post reflow soak time will cause solder joint failure in the long run. Gold – Tin and gold – Indium boundaries will create brittle interface which easily cracks. NEVER use Indium on gold plated solder pad. Indium will migrate and diffuse to gold and cause joint failure.
Although tricky to master, manual soldering with SAC305 will create superior thermal performance compared to 63/37. Pure Indium solder is better than SAC305 but has some limitations such as maximum running temp, pads compatibility, and ease of reflowing.
[Clemence]
www.virence.com
Physical and thermal properties of solder alloy - Shooting Beamshots With HDR - Nichia E21A Tint Shots
Its Okay To Be Smart - SmarterEveryDay - Deep Look - Veritasium - Tech Ingredients
Thanks for the flux tip Lexel.
I find it curious that fake Amtech NC-559 costs twice as much as generic brand NC-559. I wouldn’t expect them to perform any different thought the price difference suggests that maybe they are not the same. Have you tried the generic ones?