Nearly 18 months ago Allyn sent me one of his excellent express chassis. This was great except I'd ordered a liverpool. We had a brief exchange where he offered to send the right chassis but I wasn't fussed, I'd build an express.
During the next year the Rocket emerged as the amp I really wanted so the plan changed to a Rocket with KT66's. After my usual 6months of procrastination I finally started my Rocket.
I purchased a small chinese drill press and proceeded to drill the transformer mountings. My punch set for some reason does not include a 1 3/16 Octal chomper so I decided to use a dirty trick I used for my Lightning - a regular spade bit (hey it works!!)
I mounted the spade bit and drilled. The chinese drill press seized. I moved it down to slowest. Off it went straight through no problem. I cleaned up the edges and although not a clean as the other holes - a fair effort.
I then decided to add the mounting holes. I took a socket an put it in the new rectifier position. Hey why does the power transformer only have three screws....I'd drilled err why is there this extra pilot hole... ....
It must be old age - my formerly beautiful chassis is now in the garbage and my Rocket project is on hold - probably indefinitely. I'm just too stupid to build amps
Take the chassis to a welding shop and have them cut the area out and weld in a new piece and then polish it up with fine grit sandpaper. Or you can put a piece of aluminum over that spot to support the tranny and maybe move the recto hole over towards the board more.
Don't stop building just because of this, but you do need to either follow the layout plans in TW files section for the holes.
M Fowler wrote:Take the chassis to a welding shop and have them cut the area out and weld in a new piece and then polish it up with fine grit sandpaper. Or you can put a piece of aluminum over that spot to support the tranny and maybe move the recto hole over towards the board more.
hahaha unless I had a mate in the shop that would probably cost me more than buying three more chassis from Allyn or RJ !!!
In Australia it's all warehouses - the small shops have mostly all closed down. It's DIY or get it from off shore.
lol, sorry for laughing but it is funny in a sick sort of way. I laugh because I can't tell you how many times I have drilled out a hole and then looked and, son-of-a-beach!
Then there are times I have built an amp, didn't like it and rebuilt it to something else. Invariably there are holes where there should be material. Swiss cheese is a good analogy.
Just get a plate of aluminum and cover it up. If anybody asks, tell them it is a flux dispersion shield. Or mark on the plate, "This area reserved for future expansion."
It's part of amp building, stuff happens. Really, this is a minor inconvenience. Nothing expensive went up in smoke and no one got their eye poked out.
Build the amp, don't worry about it.
signed,
Jana who has gotten trigger happy with a drill more than once.
They also make an alumunium welding stick now that you can weld using butane torch if your DIY. Forget the name of the stuff.
Sorry it isn't convenient for shops in your area. Since Australia is a huge farming country one would think there would be plenty of people with tig welders that could do the job.
I have been doing things myself for so long that I didn't think about my reply to you very well did I.
Jana wrote:
Just get a plate of aluminum and cover it up. If anybody asks, tell them it is a flux dispersion shield. Or mark on the plate, "This area reserved for future expansion."
Build the amp, don't worry about it.
signed,
Jana who has gotten trigger happy with a drill more than once.
Nick , I'm sorry you feel so bad about your attempt at a 'perfect' build . I wouldn't put it in the garbage though . Jana had me laughing so hard at such a cute yet brilliant situation .
Ken would always implement the ' run whatcha brung' mentality . Ask yourself whats great about this situation? It challenges you to shift gears here . Challenge yourself to overcome it . You could go to a hardware shop and buy a rod to use with a propane torch to patch the hole and sand her down yourself , or you could take Jana at face value . Add whimsy or an artistic approach . Use a veneer on the whole top of the chassis or just for the transformer . Use a beautiful piece of wood to accentuate the area or the xformers together . Maybe just use it as another Star ground lug , who knows . You can do it . But don't feel so bad and strain the crane(ium) .
Been there, done that. Coming from Europe I ordered the 240V version of the Heyboer powertranny from Toneslut. These have wires coming out on both sides though, not like the american ones where all the wires go neatly through one hole on the further side of the chassis, so I drilled the two holes and found out that I should have drilled the 'bigger' hole near the outside and that my second hole was also quite big. Anyway, fortunately for me it was not a big problem, only on a cosmetical view she's not flawless, you can see the cap stack through the hole on the outside...
I also used spade bits by the way but with a cordless hand drill (Bosch PSR12)
M Fowler wrote:They also make an alumunium welding stick now that you can weld using butane torch if your DIY. Forget the name of the stuff.
Sorry it isn't convenient for shops in your area. Since Australia is a huge farming country one would think there would be plenty of people with tig welders that could do the job.
I have been doing things myself for so long that I didn't think about my reply to you very well did I.
Mark
Haha not a farm, a quarry Mark! Uranium, Iron, Zinc, Lead, Aluminum, Coal. Climate change is driven by other people burning aussie coal!!
I did pull the chassis out of the trash. I thought aluminium welding was all black art and argon shielded flames or some such. If you remember the name I'm very interested.
Thanks to all for the encourgement dudes. I can assure you that I have done heaps of stupid things in my 53 years but I'm kinda bored with exciting self created detours. It is very satisfying to walk away from broken things once in a while. My wife and kids already create an endless stream of destruction for me to clean up (eg wife blew up the microwave last night by running it empty as a timer!!! )
Jana wrote: ... holes where there should be material. Swiss cheese is a good analogy...
Morgan Jones builds a lot of (HiFi) amps with a ventilated chassis, using perforated aluminum.
I always wanted to add holes for ventilation
nickt wrote: ... I have done heaps of stupid things in my 53 years...
53 years That's the problem When you grow up and get to be as old as gahult and me, you'll quit makin' those mistakes
You're lucky. You only threw it in the trash. I, on the other hand, would have taken the ball peen hammer to it, creating a lovely hammered aluminum vessel for my wife
drhulsey wrote:
53 years That's the problem When you grow up and get to be as old as gahult and me, you'll quit makin' those mistakes
You're lucky. You only threw it in the trash. I, on the other hand, would have taken the ball peen hammer to it, creating a lovely hammered aluminum vessel for my wife
Tim, you're not THAT old and besides I'm NEVER growing up - I'd have to vote and fill in a tax return
Nickt, who told you that climate change is caused from burning aussie coal. Save the earth by finishing your amp with the chassis that you already have. And stop listening to Al Gore who flies around the planet in his private jet and tells people to turn the heat off in their houses.
loctal wrote:Nickt, who told you that climate change is caused from burning aussie coal. Save the earth by finishing your amp with the chassis that you already have. And stop listening to Al Gore who flies around the planet in his private jet and tells people to turn the heat off in their houses.
Don't have to listen to Al Gore. It's basically the entire scientific community minus the folks who work for oil/coal producers and their big customers.
Remember the disinformation fed to he press by big Tobacco?
Someone else posted who had used it, but I couldn't find the reference. Maybe someone else is familiar with the Harbor Freight product, apparently it's less expensive than durafix.
)
That's the problem 
