JTM 45/100 - Build story

[Homebelly]

I don't suppose you have a line on where i might get me some of these?
I've got the modern selectors for my build, but the chassis is measured and cut for old style..

Thanks Karlis ! your post on metro a year or two ago was a part of this start too !

some more pieces. getting closer ....
old selectors - RS wirewound resistors 470 ohms 5 watts. perhaps for some kind of 7026 build.

[Xplorer]

Sorry no, i managed to get all i could in a deal, that's all there was. and i found them a year and a half after i started to look for these, just when i thought about using modern selectors instead.
Steve Marshall and i worked on a replica, but Steve didn't work on it yet, quite busy i think. and it's not easy to produce many.
You should perhaps mount the modern selectors from the inside, you know ? if there's enough room, and no contacts, so it doesn't go through the chassis but the selection can be made just like with the old style. actualy, mounted just the same way as the old ones, just bigger, and a different mounting holes spacing. It'll also look cloer.
Then later, if you find some old ones, swap them if you like.

[Homebelly]

Sorry no, i managed to get all i could in a deal, that's all there was. and i found them a year and a half after i started to look for these, just when i thought about using modern selectors instead.
Steve Marshall and i worked on a replica, but Steve didn't work on it yet, quite busy i think. and it's not easy to produce many.
You should perhaps mount the modern selectors from the inside, you know ? if there's enough room, and no contacts, so it doesn't go through the chassis but the selection can be made just like with the old style. actualy, mounted just the same way as the old ones, just bigger, and a different mounting holes spacing. It'll also look cloer.
Then later, if you find some old ones, swap them if you like.

this is the route i've been looking at..
having said that, i'll probably just suck it up, cut the chassis, and use the modern switches..
I'm looking forward to seeing your builds grow into life..
i should post something about mine

[Xplorer]

if i were you i wouldn't cut the chassis. i would leave the smaller old style selectors holes and mount the modern selectors behind the chassis, see ? so it looks just like the old ones and you still have the possibility to swap them later.

for now i'm waiting for a tool, some advices regarding what i said previously, a few pieces on their way, and some time : then i should start the build.

[BoogieEngineer]

How are you going with the build? Any pics so far? Man those things are just so beautiful

[Xplorer]

Hi ! i didn't start yet ! still waiting for the NOS RS turrets and a new drilling machine i'll have to order. you know ... things delayed for months sometimes ..

here's a picture of some more parts.

[neikeel]

Hi ! i didn't start yet ! still waiting for the NOS RS turrets and a new drilling machine i'll have to order. you know ... things delayed for months sometimes ..

here's a picture of some more parts.

So you are going stock spec, not Dickinson/Hendrix then?

[Xplorer]

Hi Neil. well i'm thinking of starting first with the stock specs, perhaps with the 16uf RS ( if this old cap is still useable ? what do you think ? and what about the choice for the other caps ? 10uf rifa ? sprague ? ... ) , 560pf 250pf, and from there, after i'm used to it, i may try some other specs, inluding the dickinson specs in the end.

[VintageCharlie]

Adrien, you've ordered extra a drilling machine to drill a couple of holes in the cap board / chassis? Insane! - i was close to that too

[Xplorer]

About which holes are you talking about ?
the drilling machine is for some pedals i'd like to finish, and to dig the holes for the vintage selectors, into the blank rear pannel on one of the chassis i have. this chassis is the same as the 7026, exactly ^^

but i've lost four months because of a damn french ebay seller ( i'm french ) who was a liar and didn't want to refund me at first.
now i have to order another one, after this problematic one.

for the pedals, guys, i have a design idea that has never been made before. i'll experiment it, but let me tell you : everyone is gonna copy me after that ...;
i'd need a brand or something, to be recognized as the first one ... beautiful stuff. and usefull.

[BoogieEngineer]

I had to widen the hole for the choke's wire on my chassis because the grommet wouldn't fit. It's fine if you have the right grommet though. Also if you want to go star grounding, you'll have to drill a couple of holes for that grounding scheme. That's what I did.

You've got lots of wonderful parts there, and looks like you've been waiting forever. I say get started with the build now. It's a lot of fun. The sooner you begin, the less pressure there will be after you've gathered all required parts/tools.

[Xplorer]

it'll be fine, just waiting some essential nos RS turrets to arrive.

do you have a layout of your star grounding ?

[BoogieEngineer]

I followed shakti's instructions in this topic: http://forum.metroamp.com/viewtopic.php?f=32&t=25672" onclick="window.open(this.href);return false;. It's quieter than my 1969 Superlead but isn't dead quiet. I probably was expecting too much

[neikeel]

You will find that a bulgin socket is the right hole centres as a drill guide for drilling the selector holes .

If you get too anal you will be very disappointed if and when you make a mistake yourself (Bhuddism has a lot to be recommended in the respect of allowing a little room for perfection next time ).

I am leaving my original 45/100 with stock settings too but my present 7026 build will be as exact as I can make it down to the Iskra 33k< RS 560pF and grey RS caps throughout. Not sure what make that green 0.022uF coupler is (ERO ??).

Although I will not be polishing the grain out of the chassis to avoid criticisms before that I have made them too close to an original that makes them a 'fake' And will not be knocking lumps out of the front panel or charring the cap board! I would like to make a JH EXP stencil tho'.

[Xplorer]

Ha ha. No i didn't plan to go that far. I perhaps have the same syndrom as you and karlis though ^^
( it all started with a topic from karlis after i wondered and searched what early amps jimi played , curious )

Little by little, yeah i gathered all these parts. It learns parience ; )
I just want to have the pleasure, before all, to build this amp without being stuck because of some parts missing..

Actualy, on an original 45/100, the bulgin socket has a slightly different dimension, over the selectors holes if i remember.

Yeah, i'll polish my chassis .... It has to be, on mine.

The cap board : already damaged "naturaly" ! It's an rs paxolin board that has been used by some electronic students, they dug holes etc ..

Yeah, a hendrix stencil, that's so classy ....

I'll see what i can design from the layout if shakti, thanks