Amp build for a first time builder?

[yoyohomieg5432]

is there any particular brand/gauge of solder I should use?

i've had some solder laying around the house that's probably at least 5 years old. I'm wondering if this should do the trick or if I should pick up something new?

[martin manning]

Most people prefer 60-40 Pb-Sn solder, I like 0.032". If you don't want to buy a lot, Radio Shack 60-40 solder is actually quite good, and the flux doesn't turn dark. You'll also need some desoldering wick, which you can get at Radio Shack.

[Firestorm]

Also buy the Radio Shack solder sucker thing. You will use again and again. The Radio Shack one will not last like some others, but is cheap. I have hardly ever used anything but Radio Shack solder and never had a complaint. (Guys please don't rat me out; I am trying to be vaguely professional).

[Reeltarded]

Unlike these uppity metropolitains, I have never used anything but radio shack 60/40 and I fashion my solder suckers from empty big gulps with tape around the straw.

(Just kidding. I add and heat the old stuff up until it runs off the board into the chassis.)

[martin manning]

Ok, new layout drawing posted back on page 9: https://tubeamparchive.com/viewtopic.ph ... 321#226321 It now has three speaker jacks for 2/4/8 output, and a main and cap board layout page. The OT lead colors match the MC part, and I flipped the primary wires to get the phase correct since my drawing started squealing uncontrollably (just foolin'... its wired according to MC's spec sheet).

There's also a BOM posted there. I used Hoffman's to get started and then mod'ed it to match the posted layout. On the right are Mouser part numbers for the extra parts. It also has part numbers for the tone stack and PI parts to match the '59, but those may already be in the Mojo parts kit. I'd buy extra eyelets and ground lugs, and I usually buy at least $1's-worth of any one part number.

When you get everything you'll have to figure out exactly where to put the extra eyelets, and where and how you will mount the board to the chassis. You may find that removing some of the existing eyelets is best. To install new eyelets you'll need a 1/8" drill and a setting tool, which is nothing more than a steel rod with a conical point on one end. A center punch will work, or you can buy an eyelet tool at an art/craft store like Michael's.

[Structo]

Just to be different I like to use eutectic solder.

No not a brand name but a solder in which the ratio is 63/ 37 instead of 60/ 40.
I use "No Clean", 63/ 37, .031" in diameter.
The No Clean solder leaves very little residue (flux) when soldering.
The stuff I have here now is made by MG Chemicals.

http://en.wikipedia.org/wiki/Solder

A eutectic solder melts faster and sets faster, which I feel lessens the chance of a cold solder joint.
Basically it has a narrower window of the plastic stage of the solder.
A cold joint has a rough appearance and can cause a bad connection.

Cold solder joints are most often caused by movement of the items being soldered or not good temperature regulation.
If anything moves at that point the solder will not set properly.

Whatever solder you get make sure it is Rosin Core or stuff that is made
for electrical soldering.
Never use acid core solder which is used for other types of soldering.

A good solder joint is smooth and shiny.

Sorry that was a lot of words.....

[yoyohomieg5432]

just a quick update:

-my order from triode arrived: OT/PT/choke, tube covers,and retainers
-tubes arrived from tube depot: 2xtung sol 5881, 2 EH 12ax7, 1 EH 12ay7, 1 JJ gz34

-mojotone order was placed and i received shipping info today. everything shipped except 2 parts from the parts kit were backordered: a 47pF and 250uF capacitor. i'm assuming they just ship these out when they get them in right?

I'm thinking the first thing I'm going to do is mount the transformers onto the chassis. This way I'll figure out if everything will fit as is, and if some mods need to be done I'm home so I have access to the tools I would need. next i was thinking of mounting tube sockets, pots, etc, and then soldering the turret boards. thoughts?

[Firestorm]

just a quick update:

-my order from triode arrived: OT/PT/choke, tube covers,and retainers
-tubes arrived from tube depot: 2xtung sol 5881, 2 EH 12ax7, 1 EH 12ay7, 1 JJ gz34

-mojotone order was placed and i received shipping info today. everything shipped except 2 parts from the parts kit were backordered: a 47pF and 250uF capacitor. i'm assuming they just ship these out when they get them in right?

I'm thinking the first thing I'm going to do is mount the transformers onto the chassis. This way I'll figure out if everything will fit as is, and if some mods need to be done I'm home so I have access to the tools I would need. next i was thinking of mounting tube sockets, pots, etc, and then soldering the turret boards. thoughts?

Check the fit of the transformers, but don't mount them for real until the end. You'll find it a easier to wire everything (especially heaters) without that 20lbs. of weight.

[martin manning]

just a quick update:

-my order from triode arrived: OT/PT/choke, tube covers,and retainers
-tubes arrived from tube depot: 2xtung sol 5881, 2 EH 12ax7, 1 EH 12ay7, 1 JJ gz34

-mojotone order was placed and i received shipping info today. everything shipped except 2 parts from the parts kit were backordered: a 47pF and 250uF capacitor. i'm assuming they just ship these out when they get them in right?

I'm thinking the first thing I'm going to do is mount the transformers onto the chassis. This way I'll figure out if everything will fit as is, and if some mods need to be done I'm home so I have access to the tools I would need. next i was thinking of mounting tube sockets, pots, etc, and then soldering the turret boards. thoughts?

Yes I expect that Mojo will send you the back-ordered parts soon. They are the snubber cap for the PI output, and the V1a and b cathode bypass cap. You could essentially build the whole thing without those.

Checking the fit of everything before beginning any real assembly work is a good idea. Do you have your Mouser order together yet? They will ship quickly so no rush, but you will be needing those parts soon. I'll write up some assembly instructions for you and include some basic tips and techniques. Good practice for my technical writing...

[rp]

For solder Kester 44 is the shizz. I try to be as green as possible but I just can't get the hang of the new stuff. I bit the bullet laid out $160 and stocked up for a lifetime, before they ban the lead stuff for good, and for my move to Italy. Hopefully the ROHS police isn't hot on my trail

http://www.all-spec.com/products/KW4460.html

[martin manning]

Ok homie, there is now a build guide posted on page 9 along with the layout and BOM. https://tubeamparchive.com/viewtopic.ph ... 321#226321

I made a few tweaks to the PT primary wire locations in the layout, rotated the rectifier 45 degrees to show it the way it actually is, and changed one component value. The 33k resistor in the bias supply is now 27k. I don't know exactly what voltage will be needed to bias the new production 5881's, so you may have to tweak it anyway.

For the build guide I mentally built the amp and wrote as I went, and tried to include some general construction tips that are appropriate a rookie builder. I've read through it several times, but being your own editor is tough. If anybody sees something wrong, let me know.

[Structo]

Thank you Martin, that took a lot of effort to write that all up.

That should help anybody who is new to amp building.

[yoyohomieg5432]

just a quick update:

-my order from triode arrived: OT/PT/choke, tube covers,and retainers
-tubes arrived from tube depot: 2xtung sol 5881, 2 EH 12ax7, 1 EH 12ay7, 1 JJ gz34

-mojotone order was placed and i received shipping info today. everything shipped except 2 parts from the parts kit were backordered: a 47pF and 250uF capacitor. i'm assuming they just ship these out when they get them in right?

I'm thinking the first thing I'm going to do is mount the transformers onto the chassis. This way I'll figure out if everything will fit as is, and if some mods need to be done I'm home so I have access to the tools I would need. next i was thinking of mounting tube sockets, pots, etc, and then soldering the turret boards. thoughts?

Yes I expect that Mojo will send you the back-ordered parts soon. They are the snubber cap for the PI output, and the V1a and b cathode bypass cap. You could essentially build the whole thing without those.

Checking the fit of everything before beginning any real assembly work is a good idea. Do you have your Mouser order together yet? They will ship quickly so no rush, but you will be needing those parts soon. I'll write up some assembly instructions for you and include some basic tips and techniques. Good practice for my technical writing...

Hey Martin,

Thanks again for all of your help, the manual looks great. I really appreciate it.

The mouser order slipped my mind, I'm going to get on that soon.

Mojo is a lot slower than the other places. I received my orders from triode and tube depot within like 2 days. Mojo isn't going to get delivered til Wednesday.

I'm back at school now and the last few weeks before break are going to be insanely busy for me. I'm wrapping up my senior project as well as lots of work for other classes. I decided to leave everything at home so I can focus on school.

When break gets here I'll bump this thread, I'm really excited to get going on this.

Thanks again for the help everyone.

[martin manning]

Good call, it'll keep. If you find time for a break, study the schematic and layout. The more familiarity you have with them, the better.

[yoyohomieg5432]

Hey everyone, just wanted to make a quick update.

-i ordered the mouser parts. everything has arrived except the 26.7k resistors. these are backordered and i have no idea when they will be shipped.

-i'll be back home Friday and probably start building saturday.