Modding a chassis

[Bob Mc]

My 5E3 project is in the planning stages so please forgive the seemingly disjointed questions. The chassis I will be using is a Gibson; in their design the power transformer stood up rather then install in an opening. I toyed with (and posted about) using the original higher voltage transformer and modding to accommodate. So now let me look at modding the chassis rather then the circuit; can I cleanly make an opening in the chassis to have a lay down style tranny?
Is there an after market stand up style I cold use?
Same question about a rectifier socket; Gibson used a SS rectifier so there is no socket. I don’t want to buy the punch to make one hole; suggestions?

[tubeswell]

You could screw or rivet a metal plate across the tranny and recto tube holes in an after-market chassis for this amp (such as Weber's). That would be the simplest way of getting where you want to go I think (short of getting a chassis made/making one up)

[Bob Mc]

Hmm,

I'm going to try and reuse the Gibson and not have one built or buy another.
The amp cabinet is the one my neighbor used to play thru and keep me awake as a kid in the 60's (playing a terrific old Gretsch thru it). The original chassis was ruined in a flood but I found another. So as silly as it sounds, the amp has sentimental value.

I guess I can drill four holes and then saw out the opening for the transformer, but not sure what to od about the socket.

[tubeswell]

Well if you don't want to fork out for a chassis hole punch, then mybe you could take it an engineering shop and get them to cut you a hole of the correct dimensions. (I don't think off-the-shelf hole drills make a tidy-enough job myself)

[petemoore]

You don't want to go here...
drilling drilling drilling small holes around to form circle, halfround file and sore hands produce a hole who's ugliness at the edges can be covered up by tube socket, after wire cutters take out the 'tabs' that are left between the holes.
What I did was destroy a holesaw blade, then finished by using the scored in circle as center punch line then use small bit to cut through most of the rest, then use nippers to cut out what is left between the holes.
Brutal misuse of tools, but large hole can be made in hard metal this way..

[Steve Conner]

You can get fine-toothed metal cutting blades for electric jigsaws. To make transformer holes and suchlike in chassis, I drill holes at the corners, cut between them with the jigsaw, and finish off with a flat or half-round file. This should also work for the tube socket hole, if you drill more holes around the edge, though I must admit that I bought the Greenlee punches for those.

This isn't the neatest or safest method, but it doesn't need anything you can't get at Home Depot, and it's faster and less effort than the plain chain-drilling technique as explained by petemoore. I'm basically using a jigsaw where he used wire cutters.

Just be careful as drills and jigsaws can easily jam in the metal and hurt you, and metal shavings fly everywhere, so you need safety goggles.

The sole plate of the jigsaw will also scratch things, so the technique isn't too useful for panels that will be seen. I use a thick layer of masking tape on the metal in that case.

[Bob Mc]

Going to try it

Thanks all.
Steve
That's the method I'm going with, and heck, it's my wifeys jigsaw so why not?

PS
Are there Home Depots in Scotland?