lead free Solder and Rohs

[capmando]

New to this forum

 My goal to make a great sounding tube amp Rohs, with lead free solder.
I would like to make it on a turret board, or point to point.
 Wondering if the epoxy board and turrets could take the higher heat of lead free solder.
I've been using lead free solder, to solder my cables and seems to work great.

 Has anyone had experience with SN100e, or SN99, or SAC 305,( 422 to 442 Degrees F) melting point solder wire. How were the results?.  Could be any brand, I've been using MG.  Yes this is a challenge I am willing to take on!.
 Any reflections on experiences would be helpful
 Thanks Cheers.

[pompeiisneaks]

the boards are usually made of a kind of fiberglass, that can take extremely high heat.  The biggest question is "why"?  Iron based solder is only dangerous if you use it, and then lick your fingers over and over for a few hours ever time you use it.  The lead in it can't transmit to you very easily through your hands where you use it.  But yes it's doable.  I think about the only reason you'd need it is if you're planning on mass selling your amps in the EU to meet their standards.  In the US you can sell to direct customers (as I understand it, I'm no lawyer) with no need to meet RoHS standards.  Up to you.

~Phil

[pullshocks]

 I commend you for trying to build an amp with lead-free solder. 


I completed a build using Kester 95/5 (Tin/antimony) solder about 10-12  years ago.  It was the only lead free solder carried at the local electronics supply store. (remember when we had local electronics supply stores?).  I used a 40 watt soldering iron.  I used rosin flux that was probably not optimum for the solder and conditions.


The formulations you have may be easier to work with than what I had.  Although I completed a fairly complex build (Dumble variant) and it sounded just fine, it was a slow, smoky, frustrating experience.  The biggest problem for me is doing any kind of re-work and de-soldering.


So I encourage you to do a lot of test soldering and de-soldering before you begin your actual amp.  The solder manufacturers may have useful guidance.  I searched in the past and most of what I saw was focused on equipment and methods in the high tech manufacturing environment.

[bnwitt]

I dislike ROHS solder so much I bought (12) 1 pound rolls years ago just to make sure I'd never have to use it.

[SoundmasterG]

I dislike ROHS solder so much I bought (12) 1 pound rolls years ago just to make sure I'd never have to use it.

+ about 20.....hate lead-free solder with a passion!


Greg

[capmando]

I get all of your sentiments as lead free sounds like a pain to use.
Especially rework. That being said I wonder of the materials used by turrets or any other solder posts
compatible with lead free solder.
 
Questions come to mind then:

1) Best leaded solder  60~40, 63~ 37 or other
2) Could a circuit be built without solder for a time, then after final configuration solder it up, point to point?
wire wrap. Higher voltages Humm

Ps Tried a skylark Carr amp recently, Wow response is so quick, is it just a Harvard with better parts?

[Ed_Chambley]

If you have the heat and use heat shields like gater clips to mica caps and anything that you may be concerned with. Silver solder flows well too.


60 40 or anything close is about the same to work with. I believe I prefer kester and.. 031 size, but I have thinner too for pcb stuff.

[SoundmasterG]

I like 63/37 a little better than 60/40, and also use .031 and Kester, and keep smaller/thinner stuff around for PCB and smaller parts. Leaded solder is so much easier to work with than the non-lead stuff. Why punish yourself using the lead-free if you don't need to?


Some of the old military stuff was required to pass a full power test with no solder in the chassis, then after the test passed, solder was added. That requires wrapping the leads around the turrets or terminals in a specific fashion. Somewhere in my attic is an ex-military geiger counter from the 50's that was wired this way. I keep it around in case I need to refer to how they wired it up for future projects.


Greg

[Sonny ReVerb]

Interesting read: Standard Requirements for Soldered Electrical and Electronic Assemblies (not tube era, though)

[capmando]

Hey Solder Jockeys

It's been awhile since I used alligator clips for soldering got out of the habit, all my free gators are test leads now, Good suggestion for heat sensitive caps. I checked out and downloaded the Standard Requirements.....
Info you posted. lots of engineer hours went into that .   I thought the 63/37 might be different and worth a try.

Building my makeshift fume hood, flux smoke always seems to get in my eyes!

Capmando

[ManisMan]

67/37 has the lowest melting point of all solder, and goes immediately from liquid to solid, so there is no soft pasty phase where moving it aournd could cause a cold joint. Its either good or it isnt during the melt portion.

[shooter]

67/37 has the lowest melting point of all solder

In the way back days we called 63/37, eutectic solder

[hesamadman]

How do guys like 3rd power, Milkman, or Benson approach this? They would be required to use lead free solder correct?

[bnwitt]

67/37 has the lowest melting point of all solder

In the way back days we called 63/37, eutectic solder

Well I like what he's using.  It's 104%.  Kind of like a volume that "...goes to eleven"

[tubeswell]

Whenever I come across an amp for repair that has been made with unleaded solder, I re-flow all the solder joints with a little 60/40 rosin core leaded solder, and all the cold solder problems/cracks etc are fixed. It also makes unsoldering/pump-sucking removal easier once leaded solder has been flowed into an unleaded solder joint.

[murrayatuptown]

67/37 has the lowest melting point of all solder

In the way back days we called 63/37, eutectic solder

Yeah, I think eutectic means it's an alloy with proportions that allow both metals to melt at the same temperature, different way of saying what you did.

I have some 60/40 and 63/37 hoarded, but it's in random places behind other random things. If I can't find a roll, I have some old Heathkit manila envelopes with a short spool-less roll).