Color by Numbers Bassman 6g6B

[HommeMarrBuckley]

Hello all,

First, I know next to nothing to building an amp.  I much rather play guitar but I wanted to see if I could do it.  I saw a Bassman 6g6B chassis (Gomez) online and purchased it and in the process scored a filter and rectifier board in the process.  I started to accumulate parts which pretty much put myself in bed with the thing.  I met a man on here who was extremely helpful to me, however, after some time, I felt like a mooch consistently bombarding him with questions.  He repeatedly told me to post here for the benefit of hearing different input, as well as, guys like me that might be starting out.  So, I wanted to honor his generosity while giving him a break.  I'd thought I'd letter my questions so that it would be easier to address.   I am in no hurry because I go slow and I have limited time during the week but I will do this..I have come too far.  Mostly wiring questions.  I appreciate any and all input.

Good links for layout and schematic: (I only use the layout--not tech enough to read the schematic---dizaaang)
http://www.gad.net/Blog/wp-content/uploads/2011/06/1963-Bassman-6G6B-Layout.jpg
http://www.gad.net/Blog/wp-content/uploads/2011/06/1963-Bassman-6G6B-Schematic.jpg

A)  Here is the chassis so far.  I plan to use a ground bus wire and was wondering if this is decent placement around the input jacks (I will have to drill).  A good man suggested using RG 174 which I have.  I used heat shrink with one 68k resistor to connect on preamp tubes which nullifies the pair at input jacks.  RG 174 will connect and be grounded at inputs.


B)  The PT (classictone)  I believe the two red wires and red blue wire are placed correctly to rectifier board.  The two green wires will go to the pilot light.  Are they placed correctly?  My 18 gauge will run to the heaters from here (from pilot light).  Which wires (Green Green/ 18 gauge to power) go to which holes on pilot light (2 wings, 2 holes)  signify perhaps Top Left, Bottom Left, Top Right, Bottom Right.  Where does the green yellow go?  I realize that they should be twisted.


C)  PT Unknowns:  Black wire to Power switch?  White to ??
Does this have heater center tap?


D) OT (Mercury single 4 ohm tap)  Brown goes to pin 3 on last power tube.  Blue to pin 3 of other power tube.  What about Red?  (goes to circuit board?)
Yellow and Black--no idea---to speaker jacks?


E)  Choke (Classictone)  I have no idea where these two black wires go.


F)  Rectifier board    On the layout, it shows a 1 watt 27 k resistor under the 25uf/50 volt cap.  I bought this rectifier board completed and noticed the resistor was missing.  I was told by seller that this was the bias resistor and was not necessary.  The chassis has a spot for bias pot for which I can place resistor of my choosing.  This correct, or do I need to add that resistor there?


G)  Eyelets Boards   I believe there is no space between insulator board and chassis but how much space should I put between circuit board and insulator board?  What kind of spacer should I use?  (stripped piece of PVC or teflon or something else?)


Sorry for all the rhetoric--Again I appreciate all member's positive input.

nazdrave

[sluckey]

A)  Here is the chassis so far.  I plan to use a ground bus wire and was wondering if this is decent placement around the input jacks (I will have to drill). 

It could be. But the entire ground scheme needs to be considered. Please read about grounding in the tube amp library of information link at the bottom of this page.

B)  The PT (classictone)  I believe the two red wires and red blue wire are placed correctly to rectifier board.  The two green wires will go to the pilot light.  Are they placed correctly?  My 18 gauge will run to the heaters from here (from pilot light).  Which wires (Green Green/ 18 gauge to power) go to which holes on pilot light (2 wings, 2 holes)  signify perhaps Top Left, Bottom Left, Top Right, Bottom Right.  Where does the green yellow go?  I realize that they should be twisted.

Yes, the green PT wires are placed correctly. Put one green 18 gauge wire in the same hole as a green PT wire. Put the other green 18 gauge wire in the same hole as the other green PT wire. The green yellow connects to the chassis. Some people use a ring lug soldered to that wire and fasten the ring lug to one of the PT mounting bolts.

C)  PT Unknowns:  Black wire to Power switch?  White to ??
Does this have heater center tap?

White connects directly to the white wire in the power cord. I just butt splice solder the two ends together and put heat shrink tubing over the splice. The green/yellow wire mentioned above is the heater center tap.

Let me say a bit more about the black and white wires. Connect the black wire of the power cord to the END lug on the fuse holder. Connect the side lug of the fuse holder to one side of the power switch. Connect the black wire of the PT to the other side of the power switch. Connect the white wire of the PT directly to the white wire of the power cord. Connect the green wire of the power cord to chassis.

D) OT (Mercury single 4 ohm tap)  Brown goes to pin 3 on last power tube.  Blue to pin 3 of other power tube.  What about Red?  (goes to circuit board?)
Yellow and Black--no idea---to speaker jacks?

Red goes to the left side of the board and connects to the eyelet labeled +430V. Black and yellow go to the speaker jacks, yellow to tip, black to sleeve. All these wires are shown on your layout.

E)  Choke (Classictone)  I have no idea where these two black wires go.

They both connect to the left side of the board. One connects to an eyelet labeled +430V and the other goes to the eyelet labeled +428V. Doesn't matter which wire goes to which eyelet. This is also shown on the layout.

F)  Rectifier board    On the layout, it shows a 1 watt 27 k resistor under the 25uf/50 volt cap.  I bought this rectifier board completed and noticed the resistor was missing.  I was told by seller that this was the bias resistor and was not necessary.  The chassis has a spot for bias pot for which I can place resistor of my choosing.  This correct, or do I need to add that resistor there?

The original 6G6B did not have a bias pot so the 27K is needed if you want the original circuit. But, if you want to be able to adjust the bias with a pot, you can mount a resistor directly to the pot.

G)  Eyelets Boards   I believe there is no space between insulator board and chassis but how much space should I put between circuit board and insulator board?  What kind of spacer should I use?  (stripped piece of PVC or teflon or something else?)

There is no spacer between the eyelet board and insulator board. Just sandwich them together and bolt directly to the chassis. Fender actually just used sheet metal screws.

[eleventeen]

"Brown goes to pin 3 on last power tube.  Blue to pin 3 of other power tube."

Correct. But when you first build the amp, leave these leads long and don't bother dressing (eg; routing them neatly) them. Many times they have to be reversed to cure positive feedback aka "motorboating". If you're wondering what this is, you won't if these leads are flipped around (relative to how you wire up the rest of the amp) when you power it up! Just don't trim the blue and brown to final length before you ascertain primary phasing on the OT....and if you're obsessive about mechanically bending wires around terminals, don't do that, either. Just poke 'em & flow 'em.

[sluckey]

Just poke 'em & flow 'em.

I strongly disagree with that statement.

EDIT... I misread that statement as a recommendation for all general soldering technique. After reading again I now think you were referring to just temporarily soldering the OT plate leads until proper phasing was determined and I strongly agree with that. Sorry for jumping the gun.
 

[Willabe]

 

Hey now!     Where's a moderator when you need one?   



             Brad     

[HommeMarrBuckley]

First of all, Thanks so much Sluckey.  You clarified a lot and did it in a simple way in which I could understand.  

As stated, I am a little slow but I am trying to understand as much as I can to get me to the finish line without consistently referring back to the forum.  I had to drill the steel chassis for the OT mounts and ground bus and it took some time to see my stepfather to use his bit and blah blah.  Although, I am wondering if I will have to drill again for the output tube grounds (more on this later)

All areas were understood except these

C) Power and Standby
White of power cord to white of PT
Black of power cord attaching to the end of the fuse
Green of power cord will be bolted to its own PT bolt

Black of PT to the power switch

Lugs remaining of fuse and power switch (as in pic) are connected via wire, is this setup correct?

I have a 3A fast acting fuse, this alright?

Standby Switch
Per Layout
Red from filter cap board is soldered to board and has two wires connected to it.  One wire (red) goes to rec. board and other goes to my standby lug close to bottom of chassis (as per pic)
Other from 430Volt solder point on board goes to other lug of standby.
Is this correct?  Should that one lug be that close to the chassis or do I have the switch upside down?



D) Speaker Jacks

from the OT "yellow to tip black to sleeve"
I checked online for tip, ring, sleeve
Are these wired correctly?

Should any choke or transformer wires be trimmed/cut?


H)Grounding
I checked out the grounding scheme on the site and it was very informative.  This is what I have planned but I am unsure of PT bolt grounding.
As per layout, two from circuit board top will be grounded to ground bus.  There is a black wire from filter board (between two just mentioned) that will be grounded to ground bus as well.

Green wire of power cord will be grounded to its own PT bolt as stated before.

Now,
red/yellow and green/yellow wires of PT
power tube grounds
bias wire (I have bias pot)
remaining black wire from filter board (w/ red and yellow-layout)

all will go to the same PT bolt?


Not sure how to carry this out.  Should they get different PT bolts or just one?  It's like six wires converging on one botl.  It goes against the Hoffman scheme, but should I just drill two ground points next to power tubes for them to ease some from all mentioned heading to PT?  Any ideas and pics of this would be very much appreciated.


I) Steps
Not sure how to word this and it might just be best for me just to do trial and error but I am thinking it would be best to do pots and have wires running underneath board first,  then mount/wire transformers accordingly and then mount boards and lastly wire up tubes.  I dunno.

I tried to make this as organized and easily understood as possible.  I am extremely grateful to those that put me on the right path.  I really am enjoying this immensely but just wish I had more time.  I should have been doing this years ago.  The Hunter book spurred me on and I will get the Blencowe book.  I will really want to understand a schematic.

Many, many thanks!

I really hope I only encounter the "motorboating" issue in the bedroom rather than in this tube amp.

[TIMBO]

There is a lot to take in, so I would do it in bits.....
1) mount OT and PT to make sure that they fit properly ( make sure at least one bolt is fixed to a clean surface,bare metal)
2) fit switches and fuse holder
3) fit power lead and secure with lead restraint
4) secure a tank bolt to bare metal for earth connection
5) Solder lug to earth(green) wire of power lead
6) connect PT primary leads as per schem

There is some things that you might already know, this will get you started.

REMEMBER, SAFETY FIRST

[HotBluePlates]

C) Power and Standby
White of power cord to white of PT
Black of power cord attaching to the end of the fuse
Green of power cord will be bolted to its own PT bolt

Black of PT to the power switch
Lugs remaining of fuse and power switch (as in pic) are connected via wire, is this setup correct?

Yes.

You'll want to fit the power cord with its strain relief, possibly before making these connections but also making sure you have enough of the cord inside the amp to reach.

Recapping what you said for PT wiring; it's one big loop of:
Power cord Black -> End of Fuseholder -> Side of Fuseholder to Power Switch Lug -> Other Power Switch Lug -> Power Transformer Black wire.
The Power Cord White connects to Power Cord White, and completes the rest of the loop inside the PT.

If you have a meter with a continuity function, you can test for correct wiring by hooking the meters leads to the power cord plug pins. When touching the hot and neutral pins, you should get a beep with:
1. Power switch in the on position and fuse in holder,
2. No beep with power switch in off position and fuse in holder, and
3. No beep with power switch on but fuse not in holder

You should get no beep from the power cord ground pin to any other power cord pin. You should get a beep from power cord pin to any point on the chassis.

HINT: Rotate the fuseholder so the side lug is closest to the power switch, and bend that side lug outward a little to make wiring easier. This gives you short, neat wiring from the power cord entry to fuseholder to power switch.

I have a 3A fast acting fuse, this alright?

Yes, the schematic says "3A". But get some 3A Slo-Blo fuses, too. The fast fuse may pop on turn-on. If it does, use the Slo-Blo fuse.

Standby Switch
Per Layout
Red from filter cap board is soldered to board and has two wires connected to it.  One wire (red) goes to rec. board and other goes to my standby lug close to bottom of chassis (as per pic)

Yes.

Other from 430Volt solder point on board goes to other lug of standby.

Yes

Is this correct?  Should that one lug be that close to the chassis or do I have the switch upside down?

Flip the switch to get that lug away from the chassis. I don't know if that makes a connection through the switch with the switch in the up or down position.

Your standby switch is bigger than needed. Original Fender amps used a second "power switch" in the standby position, even through you may think the voltage rating is too low. Those are physically the same size as the power switch, mounted in the same way, and have the switch in the same position for "on".

Also, you pobably know that the black wires indicated going to the 430v and 428v points are the choke wires.

D) Speaker Jacks
Are these wired correctly?

Yes. Now add the short piece of wire between the other 2 lugs on the main speaker jack, and don't forget the wire from Yellow on the main speaker jack to the unused lug on the Ext Speaker jack. You may want to want to solder that lug on the Ext Speaker jack until you connect the feedback wire from the circuit board 56kΩ resistor.

Should any choke or transformer wires be trimmed/cut?

It's up to you. You may want to leave them full length until you are sure everything is wired correctly. Or if you're confident of their position, you could trim to length. Leave the OT wires going to output tube plates (pin 3) full length until after you test the amp.

[HotBluePlates]

red/yellow and green/yellow wires of PT
power tube grounds
bias wire (I have bias pot)
remaining black wire from filter board (w/ red and yellow-layout)

all will go to the same PT bolt?

Yes, that's fine.

Put as many as you can on one. If you run out of room, use an adjacent bolt. You shouldn't need to drill any holes, as the PT has 4 ready-made mounting points for you.

I) Steps
Not sure how to word this and it might just be best for me just to do trial and error but I am thinking it would be best to do pots and have wires running underneath board first,  then mount/wire transformers accordingly and then mount boards and lastly wire up tubes.  I dunno.

Mount tube sockets, pots, switches and transformers/choke first.

Do all power transformer/power cord wiring.

Underboard wires: You soldered wires to your board already. It's easiest to route those wires through the holes, along their underboard path and to the correct eyelet with the board out of the amp.

Mount main board. When you install the board (with another, insulating fiberboard between the main board and chassis!), all wires are ready for connection to the tube sockets. Leave all wires longer than you think you need at this point, and trim to length when making the connection to the socket.

Make rectifier board/filter cap board connections to main board.

For this style chassis, do heater wiring last.

Another tip: Your tube sockets don't appear to have lock washer or keps nuts (a nut with an integral star washer). You want to use a keps nut or lock washer for all tube sockets and transformer mounting bolts (and any other bolted grounds you have) because these keep the connection tight even with vibration.

[sluckey]

Should that one lug be that close to the chassis or do I have the switch upside down?

That's too close for my comfort. I'd either rotate the switch or get a switch that is identical to your power switch.

[HommeMarrBuckley]

HotBluePlates,
Thanks for your input.  Can't say enough about the members on this forum.


in terms of power/standby switch

Your standby switch is bigger than needed. Original Fender amps used a second "power switch" in the standby position,

That's too close for my comfort. I'd either rotate the switch or get a switch that is identical to your power switch.

Yes, I noticed on another forum (the same amp build) that 2 power switches were used.  I like how they look identical, as well. I just didn't think to ask when it came to ordering.  Needless to say, I have made about three orders now for other mistakes/forgotten parts and to think of doing it again-ugh, but I probably will.

Another tip: Your tube sockets don't appear to have lock washer or keps nuts (a nut with an integral star washer). You want to use a keps nut or lock washer for all tube sockets and transformer mounting bolts (and any other bolted grounds you have) because these keep the connection tight even with vibration.

Thanks a lot.  I never knew and probably would have never known.  Will rectify this asap.  Also, will utilize the MM on power/standby switches.  Again, I am grateful that you guys took the time to look over these things along with the layout, wiring, etc



Regards to PT grounding

Put as many as you can on one. If you run out of room, use an adjacent bolt. You shouldn't need to drill any holes, as the PT has 4 ready-made mounting points for you.

I have been looking at gut shots and don't see many with grounding this way.  Any one of pic or link of this?  Couldn't use a terminal lug for all of them....You just wrap all wires around that bolt?


In terms of the steps, I forgot to consider the face and rear plates.  I am guessing that these will have to be done first.  I am considering local trophy guy but also heard good things about this place.
http://www.bnplasers.com/index.html
Any opinions or other options?
What material is common for the plates of this amp? and what might be used to adhere it to the chassis (I realize pot mounting will help)?

Again, I appreciate all the advice.

[HotBluePlates]

Regards to PT grounding

Put as many as you can on one. If you run out of room, use an adjacent bolt. You shouldn't need to drill any holes, as the PT has 4 ready-made mounting points for you.

I have been looking at gut shots and don't see many with grounding this way.  Any one of pic or link of this?  Couldn't use a terminal lug for all of them....You just wrap all wires around that bolt?

Look at this chassis picture. See the black wire attached at a power transformer bolt? I'm saying for every wire you want grounded, take a ring terminal, crimp it to the wire, solder to secure it to the wire, slip the terminal over the bolt, tighten down a nut to keep it in place.

Click the links to see pictures of what I'm talking about.

For an example, see the picture below. The orange circle is around several ground wires bolted to the chassis (sorry I couldn't locate a bigger picture.)

You don't see it much on older amps because they just soldered to the chassis. You can too if you use a 100-150w solder iron. Bolted grounds are much easier to install and service.

For an example of wiring a ground buss to the pots, see the pot ground buss from Hoffman's board-making instructions.

In terms of the steps, I forgot to consider the face and rear plates.  I am guessing that these will have to be done first.  I am considering local trophy guy but also heard good things about this place.
http://www.bnplasers.com/index.html
Any opinions or other options?

I dunno if anyone sells a 6G6B faceplate. I'd try to buy one from someone already set up to make them before trying to figure out how to custom-make one.

What material is common for the plates of this amp? and what might be used to adhere it to the chassis (I realize pot mounting will help)?[/b]

Those plates were aluminum, or maybe sheet steel, on the original amps. Pretty thin. They simply had the background color and labeling silk-screened on. Creating new silk-screens is the bulk of the cost of that process, which is why I suggested finding someone who's already producing that faceplate. One the screens are available, it takes seconds to "print" the plate and then just drying time.

Also, these are not adhered to the chassis. They are held in place by the nuts of the pots, pilot light, jacks, switches, etc.

[sluckey]

I use solder type ground lugs. This first pic shows 4 ground lugs secured by one of the transformer bolts. The second pic shows the power cord ground lug secured to a transformer bolt but the other four ground lugs are secured by a dedicated kep nut/bolt. The type ground lugs I use have a built-in internal tooth star washer on each one but I still like the security of a kep nut.

[HommeMarrBuckley]

I use solder type ground lugs.

Where do you get those (mouser)?  Is that like a multi tab terminal?

Those pictures really help.  Thanks

[TubeGeek]

Maybe this will help…

Converted an ab165 bassman to 6g6-b a few months back.  Turned out great.

[sluckey]

Where do you get those (mouser)?  Is that like a multi tab terminal?

I've had a couple bags of #6 and #8 lugs for about 40 years. They probably came from Robins AFB. AES has some that fit #6 screws.

http://www.tubesandmore.com/products/S-H112

[HotBluePlates]

If you get them, just remember to solder to them when they're not bolted tight to the chassis.

The chassis acts as a big heatsink, and makes soldering harder.

[Ed_Chambley]

Hey Matt, got it going I see.  The guys really come out to explain things, don't they.  This is why it is great to post your builds, which I am not as good at as I should.  I simply forget to do it as I get all caught up in building that I am into my own world.

But hey, that is why I like to do it.  You have some great parts and examples of great lead dress.

[sluckey]

Is that like a multi tab terminal?

No. It's 4 individual lugs under one kep nut. Look closely...

[HommeMarrBuckley]

Thanks Ed.  Once I got to the transformer questions, I figured it was best to start taking pics and posting (and leave a good man alone).  I really appreciate all the help you gave me up to this point.  I am taking my time but I will post more as I go.  Want to move ahead but deciding on plates and need a few more minor parts---just wish I had a store nearby rather than online.

No. It's 4 individual lugs under one kep nut.

Thanks sluckey for the closeup--I will try to replicate something like that with the PT.

[Ed_Chambley]

Thanks Ed.  Once I got to the transformer questions, I figured it was best to start taking pics and posting (and leave a good man alone).  I really appreciate all the help you gave me up to this point.  I am taking my time but I will post more as I go.  Want to move ahead but deciding on plates and need a few more minor parts---just wish I had a store nearby rather than online.

No. It's 4 individual lugs under one kep nut.

Thanks sluckey for the closeup--I will try to replicate something like that with the PT.

You are most welcome, Matt.  Shipping can run up the cost on a build and the newer you are at it, the more you will forget to order or simply get the wrong part.  You do not have a radio shack or even better, an old electronic repair shop near you.  You can certainly get connectors, tools, resistors and switches suitable for amp building at Radio Shack.  Lots of other stuff as well.  There are 3 Radio Shacks near me and usually do not have what I need, but they will order it and I do not have to pay shipping.  If you need more than a couple of items, then it is best to get it from Doug since Radio Shack is expensive.

Like the switch that is close to the chassis.  If you flip it over, then you probably have one up and one down.  Go ahead with you construction as there may be a couple of things you will need.  Then you can simply order what you need.

You might as well go ahead and start getting part bins and collecting parts.  When you finish this build and play through it you will be contaminated for life.
You may even wake up in the morning and the first thing you say to yourself is I wonder what I can do with the extra tubes if the Bassman were single channel.  You may not think it can happen to you, oh but it can and probably will.

Remember to ask what each section of the amp does as you build it.  This will allow you to think about the amp in sections and as you follow the layout, find each thing in the layout on the schematic.  On the schematic, very quickly you will begin to see these sections.  Also, the signal path is very obvious.

[HommeMarrBuckley]

Thanks for your advice Ed.

Like the switch that is close to the chassis.  If you flip it over, then you probably have one up and one down. 

I was thinking that too---about just keeping it---might give it some personality to have it reversed (on/off) or perhaps just make it wonky.

I had a time getting the heps/lockingnuts.  I got nearly everything at Lowes excepts ones for tube sockets and few others.  Those were just too small for what was avail.  Will probably have to get smaller star washers hopefully at the local RS.  Other than this, I don't really need much.  Will have a time locking the ground bus in though--not sure what to use to secure that to the chassis--solder terminal?

In general, and might sound dumb, but is it best to put on nut on both sides of choke, PT, and OT, tube sockets?
Also, the nuts on the PT seemed to be like adhered/glued to the PT and hard to screw off (I didn't) dunno if they're supposed to be removed? --I will post a pic of what I mean tomorrow.

[HotBluePlates]

... is it best to put on nut on both sides of choke, PT, and OT, tube sockets? ...

Not unless you need it for spacing purposes. Otherwise, a lockwasher/nut or keps nut on one side does the job.

... the nuts on the PT seemed to be like adhered/glued to the PT and hard to screw off (I didn't) dunno if they're supposed to be removed? ...

If you're talking about the ones holding the endbells on, you probably have trouble unscrewing them because a lot of manufacturers dip the completed transformer in varnish to seal out moisture. That tends to "glue" those nuts/bolts in place.

Unless you're painting the endbells, you probably oughta leave those bolts alone. The transformer won't fall apart, but you'll just be putting it back together later.

[HommeMarrBuckley]

Here's a pic of the PT nut that I was referring to.

..... you probably have trouble unscrewing them because a lot of manufacturers dip the completed transformer in varnish to seal out moisture. That tends to "glue" those nuts/bolts in place.

So, I shouldn't try and remove this nut?  This leads to the reason I asked about having a nut on both sides.  If I don't unscrew this, it kinda gets in the way of the PT mounting holes and will have a nut on each side.  Difficult to get it completely flush against chassis.  Regardless, I assume that's just the way it will have to be.

Struck out at Lowes and Radio Shack for finding external star washers small enough to lock up/secure tube sockets.  Dang.

 

[HotBluePlates]

So, I shouldn't try and remove this nut?  ...  If I don't unscrew this, it kinda gets in the way of the PT mounting holes and will have a nut on each side.  ...

Leave it alone.

You see how you have plenty of thread on the bolt, right? Just slide that through the mounting holes, and add your keps nut on the inside of the chassis to hold it in place.

...  Difficult to get it completely flush against chassis.  ...

You and every other amp maker in the world. I don't know anyone that takes those off on a lay-down PT like you have pictured. Just not necessary to remove.

[sluckey]

Struck out at Lowes and Radio Shack for finding external star washers small enough to lock up/secure tube sockets.  Dang.

Don't you have a Fastenal store nearby? Or you could use eBay...

http://www.ebay.com/itm/Zinc-Plated-K-Lock-Nut-4-40-100-Pcs-Keps-External-Tooth-Lock-Nut-/260964180976?pt=LH_DefaultDomain_0&hash=item3cc2ad63f0

[HotBluePlates]

I think the home improvement places have #4 and #6 split-ring lock washers. Not everything has to be star-toothed. 

[Ed_Chambley]

Matt,
The Lowes near me has #4 screws, washers and nuts.  They are a little tight going through the tube socket, but will work.  A lot of times for tube sockets I will use rivets, but I have never had a problem with #4 coming loose with a simple lock washer.  It is not necessary, but I usually use blue loctite and cut off any most of the excess threads.  I use it on the transformer bolts as well.  I am sure it is not necessary as my original 62 bassman was not built this way and it seems to have held together for a little while.

In the hardware drawers at lowes they usually have star washers in every size, standard or metric, but as with any inventory control these days they may have removed some items from the store you go to.  I am not sure of the population of you area, but home improvement places build smaller stores in lower population areas.

I am very lucky.  I still have a local hardware store called Cranes Hardware.  You know, where they meet you at the door and put you nuts and bolts in a small paper bag.

Sluckey mentioned Fastenal.  They are all over the place and probably one near you.  There are 2 within 5 miles of my house.  Man, they have loads of variety.  Just looking at their catalog can give you some new ideas of how you may build something.

I have never removed the bell end bolts when installing a lay down Power Transformer.  I have to paint them or repair a winding, but that is the only reason.

[HommeMarrBuckley]

I checked out Fastenal and that looks like the place.  Never even knew.  Thanks for pointing me in the right direction.  Should be set for now and will update as I progress.  (on side note, also wiring 7 way with pushpull on my strat)  Should be good practice on those small pot lugs before I attempt ones on amp. Don't want to singe them off.
Cheers.

[HotBluePlates]

... Sluckey mentioned Fastenal.  They are all over the place and probably one near you.  ...

Nah... Sluckey's just a Carl Edwards fan. 

[sluckey]

Listening to John Boy and Billy yuck it up is about as close to NASCAR as I want to be. (Please don't tell the neighbors.) But I'm a big fan of shiny hardware. Fastenal was founded by Tim Taylor. Used to be Binford. 

[HommeMarrBuckley]

Ive got 12 gauge copper for my ground bus bar but I am unsure how to twist it neatly around a bolt.  Most likely will have to use a solder tab/terminal.  Anyone have a good pic of this?  Don't want to put too many kinks in the bar and was looking for ideas.

Oh yeah-Fastenal worked out--in fact didn't have to purchase the mega 100 piece (keps) bags because they were already opened.

Much appreciated.

[sluckey]

Ive got 12 gauge copper for my ground bus bar but I am unsure how to twist it neatly around a bolt.  Most likely will have to use a solder tab/terminal.

Just use your needle nose pliers to bend it.

[HommeMarrBuckley]

Work and holiday held me up.  Oh well.  

These just arrived today.  

I wasn't planning on speakers just yet but was reading other builds and looked into them.  I know Celestion V-30s are prettier pick but read good things about these.  Seem to still be on discount at popular web retailer.  So when the hemp cone gets smoking---look out.

[HommeMarrBuckley]

I tend to get ahead of myself but was looking for info on saftey checklist after build is complete.  I don't want to destroy something.  I know I am not quite there yet but I was reading Ruby's steps upon first powerup and was wondering if many on here used that or something different.  I noticed it involved some trans not being soldered and considering I am at that point right now I wasn't sure if I should skip on those soldering points and adhere to those/his guidelines.  I felt like I am going to go through a number of fuses as well after what I read.  Any other reputable directed reading on the subject is appreciated.
Thanks

[Ed_Chambley]

I have always simply built the amp first.  Then I put it on a dummy load or speaker load.  Then with no tubes in, I plug it into a lamp limiter.  If the bulb goes dim, I check the negative bias voltage.  If all is good, the I put the tubes in and check to see if all my filaments (heaters) are lit.  If I am still good, I flip off standby I get voltages from each tube to see if they ok.  Check the bias on the power tubes and adjust as necessary.  Then jam.

After I am sure everything is cool, I let the amp idle for a few hours and recheck bias and adjust if necessary or I just turn the pot until I like the tone and see no red plates.  I recheck to make sure I am not waaaaaaaaaaaaaay over 70%.

I have never popped a fuse on a build because...................................wait for it



I use breakers.  Get you a box of Buss slow blo 2 amp fuses or whatever your amp uses.  I have a Marshall Plexi that has had a .5 amp fuse in it for years.  I usually use smaller current fuses.

Matt, mainly do the best you can and post photos of your progress.  When you are complete building it there are a few folks here that will guide you.  Not to worry.

[Willabe]

Good solid information, IMO. I do pretty much the same.


           Brad     

[HommeMarrBuckley]

Well, after my twin girls' birthdays and my son's all within a month of each other along with the three holidays compounded together with the wintry weather (east coast), I finally had some moments to myself.  It took me quite awhile to figure out where I was.  I wasted much time just picking a spot to start.

I must say that looking at build pics really makes it look easy.  
I thought I would have at least got to wiring the lamp, rec/filter board and heaters but no such luck.  The power cord strain relief was really frustrating.  It feels a bit loose (the plastic piece itself-not the cord) and I think that's due to perhaps the chassis hole being a tad big.  

I got the ground bus and pots done for the most part other than those that connect to the board.  I tried to layout and space components as best as possible.  Input jack area w/ RG174 is pretty snug and tight.  It makes you appreciate clean and neat builds that I have seen here and elsewhere.  (I couldn't imagine point to point wiring that's elevated)

I have similar AC/Standby switches and some solder lugs for grounding are en route.  I contacted local trophy guy (actually girl) and she's "working" on the plates.  It's been two weeks now and I should probably give her a ring.  I just hope she's able to do it because she didn't seem so enthused.

Here are some pics.  Any comments are appreciated.  TIA
All the best.  

[HommeMarrBuckley]

I am moving along and was looking for some advice in terms of grounding.

I have one and two hole lug terminals for grounding to the PT bolt. 

I have the bias ground and PT red/yellow wire connecting on same point.
Should PT green/yellow be on that point as well, or seperate?
The black wire from filter cap board: does this meet on one of these points, as well, or seperate?

The output tube grounds: Should they both be grounded at one point together or seperate?  Should these wires be twisted?

I was going to twist PT red/yellow and green/yellow wires together, do you think I should twist the bias wire with them?

Just mounted bias board and pilot light and beginning to solder heaters.  The circuit board is tricky because mounting screw is under the OT and another is under filer cap board.  Also misjudged length of few pot to tube wires---dang.
The power cord white to PT white inline twist was difficult for me.   At first try, it went well but forgot the heatshrink--had to unravel and go again.  Then after a second time, I began to heat heatshrink and must have got too hot.  A tiny hole popped in it.  You think this will be a problem?  Meaning the wire might be hot and heatshrink lining will gradually seep out?  Hopefully, I am just paranoid. 

Thanks in advance

[Ed_Chambley]

I am moving along and was looking for some advice in terms of grounding.

I have one and two hole lug terminals for grounding to the PT bolt. 

I have the bias ground and PT red/yellow wire connecting on same point.
Should PT green/yellow be on that point as well, or seperate?
The black wire from filter cap board: does this meet on one of these points, as well, or seperate?

Center taps to same point as well as negative from filter caps.

The output tube grounds: Should they both be grounded at one point together or seperate?  Should these wires be twisted?
Here, I use a 1 ohm resistor so later you can measure ma to get bias.

I was going to twist PT red/yellow and green/yellow wires together, do you think I should twist the bias wire with them?
Not sure what is meant by Bias wire.  Yes, you can twist ct wires.

Just mounted bias board and pilot light and beginning to solder heaters.  The circuit board is tricky because mounting screw is under the OT and another is under filer cap board.  Also misjudged length of few pot to tube wires---dang.
The power cord white to PT white inline twist was difficult for me.   At first try, it went well but forgot the heatshrink--had to unravel and go again.  Then after a second time, I began to heat heatshrink and must have got too hot.  A tiny hole popped in it.  You think this will be a problem?  Meaning the wire might be hot and heatshrink lining will gradually seep out?  Hopefully, I am just parano

This is not a problem as the wires should not get hot. 

Thanks in advance

[HommeMarrBuckley]

Thank you Ed

In terms of output tubes, I was planning to ground them to PT bolt.  Perhaps those 1 ohm resistors can be added at the end. 

Yeah, I was a little ahead of myself.  I didn't mean bias wire but ground from rectifier board.

[Willabe]

Read this on grounding if you haven't yet, it should help you.

http://www.valvewizard.co.uk/Grounding.html


           Brad     

[HommeMarrBuckley]

I thought I would update progress.  On a side note, this weather really sucks but it is what it is.
I had some flubs and believe I gained a little understanding of why some might like using turret boards.  I had two wire length issues that came about after mounting the filter cap board and circuit board.  Poor planning on my part.  I could have desoldered many points and removed insulator and circuit board but chose not to because I am hoping they are not grave issues.  


Here's the filter cap board.  These wires are currently a bit more taunt.  I also have a cap cover and believe that I should add some kind of insulator to top of the cover to help reduce rattling of caps.  


Here's corner which shows pilot, PT, rec board and fuse.  Here you can see slight crack (heatshrink) white/power cord crack that was mentioned earlier.


And next section moving along.  Power, Standby and bias pot.  Here you can see where I messed up length to v6 power tube-brown wire with heatshrink.  Needless to say I was hella pissed after finishing the pots and coming to end of tube wiring to see I came up short.  Twisted the lead and heat shrank it--I hope it's fine.  Might be difficult to ascertain but following bias pot layout of Bandmaster AB763.



Here's a long view of chassis at this point.  Here I plan to have red yellow/ red/green (PT) and white (rec board) all twisted and soldered to one terminal lug on PT bolt.  Orange is ground from filter board.  Not sure if I should twist that with them and soldered to same terminal lug as others.  Power output tubes grounds.  Should they be twisted together and converge on same point on terminal lug or each have their own point.  I know Ed mentioned resistors but wasn't planning on ordering any more parts and wasn't sure wattage to go with 2-4.



Close up shot of circuit board.  I have read shorter lengths are better and my RG174 input wires are definitely not that.  Hoping that this will not matter.  Here's other wire length mishap.  2nd red wire from bottom right connecting on v2 preamp tube was short by so little.  I tugged and tugged to no avail and ended up adding a bit of a lead and soldered to end.  



I am thinking of nicknaming the guts skittles or perhaps rainbow which was not intentional at all.  All in all, I have to say that I really am enjoying this.  I still have to mount the OT and wire that along with heater wires but I don't think there's much more---Oh yeah the cabs for the head and speakers--that will be easy.  yeaaaa.  Currently contemplating if I want to venture into taking on box/dove tail joints.  All considered, this thing actually works when hooked up to a load.  What are the statistics for that?  Hopefully not the same as it being 60 degrees tomorrow.  

[HommeMarrBuckley]

And that's that......well almost.
Last stages went well but heater wiring had it's moments.  Dunno if I will use stranded wire again for heaters.  It was really difficult to have 2 stranded heater wires and jumper fit in one lug (pin 5) on the preamp tubes.  Those lug holes were skinny and very tight. Might look at different makes of preamp sockets next time.  I am lucky I didn't break a lug off.


I think I might need some adjustments but I am not sure.
A) Should I have twisted the filter cap ground (orange) in with the PT and rectifier ground (white)?
B) Should I have twisted the output tube grounds? (black--actually used leads from choke trimmings)
C) From photo above and this one, I believe I might need to trim OT wires or at least find a better way to tuck them away.  The ones going to SPKR/EXT. SPKR might work tucked in and around chassis back.
As told to me earlier in post, I might have to reverse OT primary leads to output tubes (brown/blue) due to oscillation.  



Bias pot

D)  Is nut to close to the pot?  Is bias pot too close to tone control pots?  I have it propped on a washer to clear the nut.
E)  Perhaps I should trim wires here?  believe so
F)  Put a 15k resistor as per Bandmaster layout



Bouncing back and forth with Merlin book and Megantz.  Currently Megantz.  His initial power up is pretty thorough and seems solid, however, it might have to wait.  I don't have a cab matching the impedance and I am sketchy about using a dummy load.  (It was written to have a power resistor = impedance and > output power (which I don't know output power).  Not sure how to connect that resistor to the output but sure it's documented online--just haven't researched it yet.  Regardless, I don't think I am going dummy load route.  

Any input is respected and appreciated.    

Thanks

PS. All previous pics were removed.  Thought the slow load of the thread was only on my end.

[drew]

Dunno if I will use stranded wire again for heaters.  It was really difficult to have 2 stranded heater wires and jumper fit in one lug (pin 5) on the preamp tubes.  Those lug holes were skinny and very tight. Might look at different makes of preamp sockets next time.  I am lucky I didn't break a lug off.

Look at thinner wire instead.      20 gauge is fine for the preamp tube portion of the heater string.

[HotBluePlates]

A) Should I have twisted the filter cap ground (orange) in with the PT and rectifier ground (white)?

Doesn't matter.

B) Should I have twisted the output tube grounds? (black--actually used leads from choke trimmings)

Doesn't matter.

D)  Is nut to close to the pot?  Is bias pot too close to tone control pots?  I have it propped on a washer to clear the nut.

Doesn't matter.

E)  Perhaps I should trim wires here?  believe so

If you want.

[HommeMarrBuckley]

Than you HBP.

I am in process of having someone work with me in checking amp out(initial power up).  I am honestly timid for fear of shocking myself. 

In process of finetuning, a preamp pin broke off and will need to be replaced.  So figured now is a good time of perhaps placing an order for those power tube resistors (Ed) and future cabinet hardware that will be needed.

 I think I have a good checklist for the head and some of the cab (corners, strap, chassis straps, piggy back thumbscrews, tolex, etc.)

What I don't know is,  for this 2 x12 cab (internally)  What switchcraft jack and plate will I need?
I have got speakers, anything needed connection wise for them?
I was planning on using a divider, but wasn't sure what kind of screws/nuts were needed inside and for baffle and closed back?

I googled and there is good information and pics but I don't know what is what in terms of ordering.

Any input is appreciated.  Thank you

[Ed_Chambley]

Than you HBP.

I am in process of having someone work with me in checking amp out(initial power up).  I am honestly timid for fear of shocking myself. 

In process of finetuning, a preamp pin broke off and will need to be replaced.  So figured now is a good time of perhaps placing an order for those power tube resistors (Ed) and future cabinet hardware that will be needed.

 I think I have a good checklist for the head and some of the cab (corners, strap, chassis straps, piggy back thumbscrews, tolex, etc.)

What I don't know is,  for this 2 x12 cab (internally)  What switchcraft jack and plate will I need?
I have got speakers, anything needed connection wise for them?
I was planning on using a divider, but wasn't sure what kind of screws/nuts were needed inside and for baffle and closed back?

I googled and there is good information and pics but I don't know what is what in terms of ordering.

Any input is appreciated.  Thank you

I use t-nuts to install speakers.  4 on each, #10/24 and 3/4" #10/24 hex head (allen).  Go to ampwares.com and liik at the cabinet and you will see a photo of the back of the blond 2 12.  Count the screws.  There are a lot with washers.  Lowes and Home Depot sell the screws and washers.  The screws are the same as on the back of your head cover.

I use stereo switchcraft jacks for mono as they hold tighter.  I just wire them mono.  The cab should be 4 ohm.  If you want the authentic look, you are going to need the speaker wire with the flat, round fender cap.  The jackplate is available with the jack and is positioned facing the back of the cab about 3" from the bottom right.  It is even with the surface of the back panel.  Those original fender parts are costly, but if you want a replica look here http://www.guitar-parts.com/ for your fender hardware.

Use some sound damp material in the cab.  You can get the yellow fender stuff, but I just use 1" high density foam and use spray adhesive to put it in place.  The fender stuff gets messy as it ages.  I have seen people just use pillow stuffing and it worked fine.

Check your Tolex on your headbox.  There are 2 different blond.  Mid 62 Fender replaced rough with a smoother version.  Also originally the grill cloth was oxblood and then turned to wheat.  I prefer the oxblood and the website I posted above has the closest to the original I have found and I looked at a lot of samples.  The wheat is cool to, but it does not have a contrasting look.

[HommeMarrBuckley]

Thanks Ed,

Were those screws mentioned for the tee nuts?
Or are they for cab/head back cover?  I have seen pics and will need a lot of those.
Also, wasn't sure which jack plate on that site.

Would be great if someone in my area had one to inspect.  Sure there's plenty of pics online but, with me having no background in this, it's hard to determine sizes so forth.

Any members that got a good shot of their speakers wired up similar to mine (2 x 12/divider) is very much appreciated.

Thanks everybody.

[Ed_Chambley]

Thanks Ed,

Were those screws mentioned for the tee nuts?
Or are they for cab/head back cover?  I have seen pics and will need a lot of those.
Also, wasn't sure which jack plate on that site.

Would be great if someone in my area had one to inspect.  Sure there's plenty of pics online but, with me having no background in this, it's hard to determine sizes so forth.

Any members that got a good shot of their speakers wired up similar to mine (2 x 12/divider) is very much appreciated.

Thanks everybody.

For t-nuts I use allen #10  Thread 24.

For fender cabs I use the ones like Doug sells here:
http://www.hoffmanamps.com/MyStore/perlshop.cgi?action=template&thispage=AmpTrim&ORDER_ID=203784239

"D" screws and "B" for the washers.  If you are buying enough for a 2, 12 fender cabinet it is cheaper to get them by the box at Lowes or Home Depot.  I can't remember how many there are in the cabinet, but they have a photo of the back on ampwares.com and you can count them.

I attached a photo from Doug's inventory.  If you got other things to order you might just get them from Doug if you don't want to get a large box.  It may be cheaper, but I use a lot of them as I build cabinets.