• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Tubelab SPP first timer build

Jump to Latest
#161
Cheers for replies and support, got caught off guard with the very sad news of Q.E. II death, proclamation of King Charles III and watched some news about it all on BBC News HD & Sky News HD.
Today, we had a public holiday, so the wife decided 'we' needed to do some odd jobs today.
I'm am now getting out my papers and will see where i left off.
Up to now 90% of my parts will be from DigiKey.
As i've said from day one, the least courier charges i pay, the better.

The case i'll make a decision about it tomorrow.

Hole Punches! Why are things so difficult? 🙁
I don't have any, but i'll need three types, one for the 5AR4, one for the 12AT7 (ECC81's) and another one for the EL84's.
Once used, never to be used again 😡

I'll be checking the Valve diameters and also the size of the Valve sockets, to make sure.
Digikey don't appear to have any.....
First jobs in the morning.
 
#162
Do you know of any tool and die shops in your area? May be a generalization, but I thought the Spanish were/are decent metal-workers. It might be easier to pay a pro to put 7 holes for the tubes in your top plate. Any shop with a CNC milling machine could probably do it in less than an hour. Didn't you say you have Spanish in-laws? Maybe one of them knows of a shop.
 
#164
Steve Morley said:
Do you know of any tool and die shops in your area? May be a generalization, but I thought the Spanish were/are decent metal-workers. It might be easier to pay a pro to put 7 holes for the tubes in your top plate. Any shop with a CNC milling machine could probably do it in less than an hour. Didn't you say you have Spanish in-laws? Maybe one of them knows of a shop.
Click to expand...
I'll be phoning some Builder Merchants here today, he's hoping, though doubtful.
Spanish metal workers places will be across the Spanish border and passing through their wonderful police border controls, and join the queues they form to get in & out of their country, so i'd rather not...
I'll have a search in https://www.leroymerlin.es/tiendas/los-barrios
CNC milling machine locally will be quite difficult

Why do things get so diificult! 🙁
 
#165
calpe said:
I'll be phoning some Builder Merchants here today, he's hoping, though doubtful.
Spanish metal workers places will be across the Spanish border and passing through their wonderful police border controls, and join the queues they form to get in & out of their country, so i'd rather not...
I'll have a search in https://www.leroymerlin.es/tiendas/los-barrios
CNC milling machine locally will be quite difficult

Why do things get so diificult! 🙁
Click to expand...
For what is worth, I found it not too difficult to using a step drill bit for the base holes:

1663070685224.png

It will never be as good as a proper CNC machine though.
 
  • Like
Reactions: calpe
#169
With inexpensive drills you wouldn't likely want to drill steel. A drill press definitely with these. Once lined up to where the hole is to go your metal plate should be clamped to the base of the drill press. Run the press at its slowest RPM and use oil or some sort of lubricant (WD40 even) to cool the bit and plate.

Practice on a scrap piece first or if you don't have any drill a hole under the centre of the power transformer (it won't show later) to get a feel for the process. If it turns out to be too incontrollable go to the next smallest size and plan on doing a bunch of filing or Dremel tool work.
 
  • Like
Reactions: calpe
#171
Thanks to you all for your very valuable advise.
I need to make notes about all these factors.

Its proving quite a slow process, between work, home life, annual holidays and trying to keep my 1/2 orange off my back, its quite embarrassing the time its taking.
Head is down on final items and the case.....
 
#172
 
#173
Most seem rated at 10 amps, which is fine for your application. Pick one that mounts through the hole from the outside with a plastic cover over th emetal mounting flange. It will hide some metal-working sins.

If you give us the actual Digikey part number you are thinking of rather than a page it will be easier for us to help.

A filter isn't strictly necessary but won't hurt if you have noisy AC.

S.
 
#176
Steve Morley said:
...smallest size and plan on doing a bunch of filing or Dremel tool work.
Click to expand...
What I do for large holes in aluminum is first find a big heavy steel washer or short piece of pipe with a hole the desired size to use as a template. Draw the hole on the aluminum then use a small drill to drill a series of holes around the inside to remove most of the material. Now clamp the washer or pipe piece tight over the hole and use it as a template to file or dremel the hole to size. It is slow but will give an acceptable result without having to find a large drill or punch.
 
  • Like
Reactions: calpe
You must log in or register to reply here.
Top Bottom