Deluxe Micro build/first amp build

[Kev-wilson]

After building a cabinet for a 15 watt clone and a matching speaker cab have decided I need a one watt amp, so have bought parts from The States and the Uk.
I can/could solder, can work safely around UK mains electricity and will learn as I go, but as a metal worker am out of my comfort zone .

First job is to fit the turrets.

Edit, first job first question, I bought a board with pre drilled holes for the turrets, I had hoped the holes would line up with the layout template but they don't, can I use the outside holes to fit the turrets in, or should I buy a blank piece of board and drill thru the hole marks? I'd prefer to fit the turrets to the outside holes.

 

[King Fan]

Good work. BTW I like your countertop. When we got ours, I read that this particular granite was popular in the UK, where it was sometimes called “pubstone”… tho I’m gonna assume you're not building in a pub.



Oh, and FWIW after my first couple builds I discovered this great build sequence by super-guru Steve Luckey. It allows you to test as you build, which tends to make startup day a lot more fun….

https://el34world.com/Forum/index.php?topic=2376.msg18247#msg18247

 

[Kev-wilson]

Good work. BTW I like your countertop. When we got ours, I read that this particular granite was popular in the UK, where it was sometimes called “pubstone”… tho I’m gonna assume you're not building in a pub.

View attachment 996885

Ah mines not proper granite, MDF with a marble/granite type covering, just my kitchen worktop doubling as a work bench as it's near the coffee pot, and I've a feeling that coffee will be more help than tea for this job

 

[Lowerleftcoast]

I'd prefer to fit the turrets to the outside holes.

That plan will work. No need for a different board.

 

[Paul-T]

Those boards work really well. That's what I used for my EF80 deluxe micro, although I crammed a couple more components in, for a 1 tube reverb with a separate power node.

 

[dan40]

You can use any holes that you like as long as you leave enough space between them to fit your components. I often use the outside holes to feed my tube socket and potentiometer wires through so I will use the second row of holes from the outside edge to mount my turrets. This method works well on 3" and wider boards but can be a bit difficult to use on narrower boards.

 

[Kev-wilson]

Those boards work really well. That's what I used for my EF80 deluxe micro, although I crammed a couple more components in, for a 1 tube reverb with a separate power node.

And thank you for showing me how to do the ground bus bar I'd wondered about insulation as a lot of photos show a bare wire and I wasn't keen.

 

[Kev-wilson]

So far so good (I hope), but will wait to solder as I can’t swear to what I’ve got being leaded and have some 60/40 coming

Not as neat as you guys but it could be worse

 

[King Fan]

I see you've cleverly left a line of holes at the top of the board. You mentioned a ground bus: if you put a few turrets there, you can run your bus on them (a bus lane, eh) and keep it away from the 'circuit' turrets in the next row down, thus avoiding the need to use insulated wire. If I'm thinking straight. Does that make sense?

 

[wangdaning]

This is how I put my bus on to mine. I had more space as this is a kind of bassman micro in a bf bassman chassis.

 

[Kev-wilson]

As King Fan mentions, there's room to put the bus on turrets on the left side, and that was because a couple of resistors had shorter legs I'm assuming I'll just strip a length of twin core & earth for the wire and could use heat shrink tube in-between the connections?

I've managed to lose my 470pf bright cap and forgotten to order an spst mini toggle switch to use as a bright switch on the front panel, what voltage & current is running through the pots btw? (bone question ) as mine are rated 1/4w and seeing the thickness of the bus bar thought I better ask I'm also 'worried' by the thickness of the wire I bought as it's thin but rated at 1000v and is solid and came in a pack of 5 x 3m lengths of different colours.

I'm going to use a double pole on/off switch, and the fuse will be in the iec socket, and aren't going to use the headphone jack as I use a Boss ME70 for late night headphone playing.

I guess I better start thinking about where the chassis holes go

 

[King Fan]

Pretinned bus bar is nice, stripped mains wire will work, or, over here, you can buy tinned bus wire in various gauges. Frankly, 22ga will work, but 16-20 is a little more rigid. It’s easier to make it go straight if you twist two strands.

Why do you want shrink tube on your bus if you can keep it away from other turrets? By definition, by physics, touching the bus is like touching the chassis. OK, it could cover the bare tarnished copper if you strip mains. Or if you put top row turrets where you need connections, you can just link them with (black?!) insulated wire.

Lots of options; I collected photos of some nice bus solutions a while back (sorry, builders, this was for my files, I didn’t note who did what — the first is obviously Doug Hoffman who has a video on his Hoffman amp pages about how he laces the turrets).



Speaking of wire, do you know the gauge of your skinny wire? Again, 22ga is sufficient throughout our smaller amps.

 

[Kev-wilson]

Thanks folks for the pictures & advice I know what I can practice tinning on now
I think my wire is 18 gauge, or it measures 0.48”/1.20mm, and I’d assume is aimed at amp builders, at least I hope it is

 

[King Fan]

1.2mm? Oh my. The wire core, without the insulation? That sounds like *British* 18ga. Even though US AWG 18ga is smaller, 1.02mm, building a whole amp with US 18ga is a suffer-fest -- the stuff is needlessly bulky, stiff, and hard to fit onto amp bits. Is yours solid or stranded? Can you take a pic? Maybe some of our UK builders can chime in with sources -- you don't need that many feet of wire to build an amp...

 

[Paul-T]

1.2mm? Oh my. Maybe some of our UK builders can chime in with sources -- you don't need that many feet of wire to build an amp...

If your wire is impractical, you can buy shorter lengths off eBay I think. I bought quite a few odd meters from tube-town but of course shipping is expensive. My favourite is the solid cloth-covered core wire. I looked around quite widely and got this. The only problem is you'll probably get tempted by all the cool valves they have too. They were nice to deal with.

WAXED COTTON WIRE YELLOW SPOOL

22 awg, solid core, 50 ft. spool. The

watfordvalves.com

 

[Kev-wilson]

This is the wire

Measured across the insulation though, it came from Modulus Amplification, it surprised me as I expected thicker tho aren’t familiar with amp wire and wire gauges, for UK 240v I’d use 1.5mm for a 6a light, 2.5mm for a 16a socket and use 6mm swa for my shed as it’s on a 35a breaker (to power a 400v converter for 3 phase).

 

[King Fan]

OK. That *looks* nice and skinny. Modulus is good. You said you got the 1000V pack? Here's their spec:

• O/D - 1.2mm
• Conductor - Solid Core 1x0.6mm

And 0.6mm is fine, roughly 22ga, I *think.*

Your household wiring experience as to gauge isn’t very relevant in an amp that only carries a few amps at most. Amp amps aren’t like other amps — they’re fewer.

”Keep Calm and Carry On.” Forget I said anything about gauge. You’ve done well.

 

[Kev-wilson]

OK. That *looks* nice and skinny. Modulus is good. You said you got the 1000V pack? Here's their spec:

• O/D - 1.2mm
• Conductor - Solid Core 1x0.6mm

And 0.6mm is fine, roughly 22ga, I *think.*

Your household wiring experience as to gauge isn’t very relevant in an amp that only carries a few amps at most. Amp amps aren’t like other amps — they’re fewer.

”Keep Calm and Carry On.” You’ve done well.

Thank you

My ohms law is rusty enough to have me wondering 'you watt' with those amp amps and other amps

I'm glad the wire's ok, I couldn't see the spec on the page, just the 1000v rating so seemed a good idea.

I thought I’d rough cut the board wires and put them on their turrets (or under for the time being) to help me learn what’s doing what

 

[dan40]

I can't tell if your wire is stranded or solid core. If it's stranded, pretinning the stripped ends will help tremendously when you go to solder the wire to a tube socket or turret. Many suppliers sell stranded wire that is already pretinned. This makes soldering the stripped end much easier as you don't have individual strands of wire going in every direction when you try to insert it into a tube socket or potentiometer lug.

 

[Kev-wilson]

Hole drilling time, first time illustrator user and struggling

I have spent far too much time trying to print that, 10” long but muppet here set it to 8” and swore long and hard at the software till the penny dropped
So I can jiggle the hole marking to suit and adjust the template as I go, hoping to ‘Uncle Doug a faceplate(if I can find a sheet of laminate as all I can see are pouches) and I've found a nice font called 'Strato' which is a Fender ish type.
I'm waiting for the power Transformer to arrive but think I'll set the valve base positioning by eye from the photos on RobRob's site as they'll be upright.
I’ve 10mm spacers under the board and am using 3mm machine screws, I found I ordered the wrong size volume knobs (too big at 31mm in a 50mm chassis) so will find smaller ones and have a channel switch to add around the pots somewhere.

Nearly time to get the iron out