newbie needs help

[galyons]

My question is can I replace some of the wire with Radio Shack wire, which is copper....

Why?  If the stock wire is the same as mine, it is good quality Carol, (General Cable) tinned copper with PVC jacket.  Radio Shack wire would, IMO, be of dubious quality. I did use mil spec silver plated OFC with Teflon dielectric for my signal path.  It was a bit brighter, sounding slightly more detailed. To me, an improvement, but hardly dramatic.
Cheers,
Geary

[Grainger49]

You can verify the resistors by putting a meter on them.  Don't do it after they were just removed.  The heat can alter the reading.  But after 10 minutes, or 5, they will read true.

[Laudanum]

Lead free ... ouch. That explains it.  That said, if you were able to get some good solder joints with it, you may want to leave them alone.   If they are all suspect, then that's another thing.   Lead free is a royal pain and I wouldnt use it for anything, plumbing excepted, but if a good joint is made with it, it works fine.  It isnt exactly a piece of cake to desolder either, especially getting it to flow so you can wick up with a solder wick.  Needs more / longer heat and you risk overheating components again.  That's the only reason why I would consider leaving those solder joints that may be ok.    Anyway, I use the Kester 63/37 Eutectic (Kester 44) for most things electronic.  But the Kester 60/40 is good stuff.  You'll immediately notice the difference and rap yourself on the head for using the lead free.  Not your fault, you didnt know.  Now you know where to ask 

Im also going to assume that the OP is asking about wire because of insulation pull back with all that heat from using the lead free.   Eileen surely would have supplied some more wire. 

I've tried the lead free just to check it out back when they had the lead free frenzy,  but I never soldered a project with it, thankfully.  So this is something I am not sure of so I'll put it out there for others who may know ...

If you have a suspect lead free solder joint, can you re-flow, adding a bit of leaded solder and to get a solid joint?  In other words, will the leaded flow with the lead free and is there any problems with the mix?
I ask because this may help the OP in not having to desolder everything.  It would be easier to reflow with a little lead free if it's ok to do so.  Assuming of course that there isnt already a boat load of lead free on the joint.

[Laudanum]

Wire -

bmurph7 ... if you are in the USA and dont mind waiting a few days on the postal service, I would be happy to send you enough of the insulated wire to be able to rewire your amp.  Same type (insulated solid core) and gauge (20, I believe) as Bottlehead includes with the kit.  I dont believe that I have any of the buss wire but that should be re-usable without any problem.   If you'd like it, send me a PM with your address information and I'll get it out in a mailer today or tomorrow.  Gratis of course.

[bmurph7]

Laudanem.. Thanks for the offer.  I still have some wire left from the original build, and I haven't received the new parts from Bottlehead yet so maybe they will send some wire.  So I think I should be OK.  I did get my new soldering station today, but won't have time to play with it until next week. 
Thanks again for the offer.
Brent

[Laudanum]

No problem.  The offer is open if you need the wire. 

[2wo]

" The offer is open if you need the wire.

That's what I love about this place...John 

[bmurph7]

After a long delay due to work, I finally got the parts I needed and reassembled my Crack.  Testing was good in Ohms tests, and good for voltage until clumsy me shorted an LED.  I replaced it, but I dropped the 6080 tube from chair height onto carpet.  Now on terminals where I should get 170v, I get 202v, at terminal 7 I get 0v instead of 100v, and at B3 I get 0v instead of 100. All the voltages that should read 170v are at 202v, #9 is 125v s/b 100v, #15 is 217v s/b 185, #21 is 230v s/b 206.  Did I break the tube?  Or could something else be wrong.  I didn't get a chance to check the B voltages before I shorted the LED and subsequently dropped the tube, but #2, #4, #7, #9, #13, #15, and #21 all had correct readings.

As always, I would appreciate any help I could get.
Thanks

Brent

[Paul Birkeland]

Hello Brent,

If terminals 1-5 read the correct voltages, then you can be certain that the 12AU7 is functioning correctly. 

7 and B3 are tied together, and 0V there indicates that this half of the 6080 isn't drawing current (9/B7 is the other half, which is operating appropriately).

What I would check is to ensure that there is voltage on B1, it should be the same as terminal 2, and voltage on B2 (which is nearly mandatory).   Next, measure the resistance from ground to B3 to be sure the cathode resistor is in properly, being aware that you might have to pop the 100uF coupling cap out. Since you haven't mentioned so, I'm assuming you don't have the Speedball.

If all these checks pass, then the 6080 may have been damaged, but this is a super tough tube, so it seems unlikely.

-PB

[bmurph7]

PB
Thanks for your help.  B1 voltage is 90v, which the manual call for.  B2 is 203v.  The manual calls for 170.  The resistence at B3 is 2.9k ohms, which the manual also calls for.  I did not remove the cap.  Since it checks OK according to the manual, I wasn't sure I needed to remove the cap.  Is there a way to check the tube?
Thanks
Brent

[Paul Birkeland]

Is there a way to check the tube?

Well, you could look around for somebody with a tube tester, but you have verified the correct bias voltage, that there is plate voltage, and that the resistor is properly connected and not shorted, so in a way you have tested your 6080.

I'd snag another one and you should be back in business.

-Paul

[bmurph7]

Sweet success! Bought a new tube and everything is good.  Amp sounds great!  Thanks to everyone for all the help.  I learned a lot, and am looking forward to my next project.
This was my first time for something like this, and I was amazed at all the help I received.  Again, I can't thank everyone enough!
Brent