Amp build - Trainwreck Express type amp in a recycled chassis

PeteC

kind of - except that the donor chassis is a fender style , with a slanted control panel at the top of the cab. 

Keefy

I think I might try eyelets on my next build. What board material and thickness do you use, what diameter holes do you need to drill, and what tool do you use to stake the eyelets?

PeteC

Hi @Keefy ;

I buy "Tufnol whale" material off eBay ( usually the 1.5mm or 2mm thick stuff )  There is also a bulk supplier based in Sheffield but I'd have to dig through my old records to find them these days.  Its pretty cheap and very easy to cut/drill. Looks very old/school/vintage too.  Watch out for cheap substitute stuff though which might not have the HV insulation properties you want. 

Hole size depends on what eyelets I can get hold of at the time.  Usually they are keystone branded pcb eyelets ( my last lot were from RS I think ) 

The board for the Express had 2.5mm (or maybe 3mm)  holes drilled on the drill press, and to stake the eyelets what I do is use the blunt end of a drill shank in the drill press chuck to push the top of the eyelet down , and under the board in the drill press vice I have a blunted countersink bit facing upward which splits and pushes the lower flange of the eyelet out into a small "star" shape under the board securing it very tightly.   Before I got my drill press I simply put a countersink bit facing upwards in my bench vice , inserted the eyelet into the drilled hole, positioned the hole over the countersink bit,  and tapped the eyelet down with a pin hammer to secure it.  Works fine but just takes a bit longer, and is fiddly if you're a bit hamfisted like me. 

Having used both eyelets and turrets I find eyelets much easier to work with. Turrets certainly look better and give you that "Hiwatt engineered" feeling, but can be a bugger to get good reliable solder joints on sometimes.  Ive done too much fault finding with them tbh.  Eyelets are much easier when it comes to modding and making quick changes too. 

Keefy

PeteC said:

Hi @Keefy ;

I buy "Tufnol whale" material off eBay ( usually the 1.5mm or 2mm thick stuff )  There is also a bulk supplier based in Sheffield but I'd have to dig through my old records to find them these days.  Its pretty cheap and very easy to cut/drill. Looks very old/school/vintage too.  Watch out for cheap substitute stuff though which might not have the HV insulation properties you want. 

Hole size depends on what eyelets I can get hold of at the time.  Usually they are keystone branded pcb eyelets ( my last lot were from RS I think ) 

The board for the Express had 2.5mm (or maybe 3mm)  holes drilled on the drill press, and to stake the eyelets what I do is use the blunt end of a drill shank in the drill press chuck to push the top of the eyelet down , and under the board in the drill press vice I have a blunted countersink bit facing upward which splits and pushes the lower flange of the eyelet out into a small "star" shape under the board securing it very tightly.   Before I got my drill press I simply put a countersink bit facing upwards in my bench vice , inserted the eyelet into the drilled hole, positioned the hole over the countersink bit,  and tapped the eyelet down with a pin hammer to secure it.  Works fine but just takes a bit longer, and is fiddly if you're a bit hamfisted like me. 

Having used both eyelets and turrets I find eyelets much easier to work with. Turrets certainly look better and give you that "Hiwatt engineered" feeling, but can be a bugger to get good reliable solder joints on sometimes.  Ive done too much fault finding with them tbh.  Eyelets are much easier when it comes to modding and making quick changes too. 

Thanks @PeteC that's great!

PeteC

Well its been a while since I built this amp and I finally got round to finishing some stuff off that I wanted to do on it : 

1) swap the 6V6s for some good EL34s ( roughly same bias in a TW Express type amp ) 
2) Install a PPI master volume - switchable between 1M and 500K for greater "clean-ish" range 
3) Add a vox style treble cut circuit ( but with a 250K and 0.05uf cap ) 
4) Add switchable bright caps (100pf - 0 - 500pf) 
5) redo the head shell cabinet 
6) Get a faceplate made for it. 

Ive done all except for (6) where I hope to send a file to Modulus to get a custom plate made. 

I think this is the best amp I have ever owned or played - its got seriously good overdriven tone even at low volume and when its opened up on the master its just great ( though stupendously loud for 30 watts )   . I've been recording quite a bit with it mic'ing up a 1x12 Thiele cab. 

Keefy

PeteC said:

Well its been a while since I built this amp and I finally got round to finishing some stuff off that I wanted to do on it : 

1) swap the 6V6s for some good EL34s ( roughly same bias in a TW Express type amp ) 
2) Install a PPI master volume - switchable between 1M and 500K for greater "clean-ish" range 
3) Add a vox style treble cut circuit ( but with a 250K and 0.05uf cap ) 
4) Add switchable bright caps (100pf - 0 - 500pf) 
5) redo the head shell cabinet 
6) Get a faceplate made for it. 

Ive done all except for (6) where I hope to send a file to Modulus to get a custom plate made. 

I think this is the best amp I have ever owned or played - its got seriously good overdriven tone even at low volume and when its opened up on the master its just great ( though stupendously loud for 30 watts )   . I've been recording quite a bit with it mic'ing up a 1x12 Thiele cab. 

I'm looking forward to seeing the face plate!

Neilybob

Wow I am literally doing the same as this, well I've just started thinking about it anyway @PeteC ;. 

I acquired a Ceriatone Expression Trainwreck clone that has come in a less than suitable amp head enclosure. Will be watching for tips and advice. 

PeteC

Nice acquisition @Neilybob ! 

They're really great amps - even though the purists reckon that you can't get close enough to the way Ken Fischer used to tune each individual Express, you can certainly get close enough to have a fantastic amp which will rival anything available commercially IMO.   Although I originally built an Airbrake clone to use with mine I have found that a post-phase inverter master volume works extremely well and makes the amp really versatile.  Yes - its pure tone insanity when the master is wide open, but honestly I don't get much opportunity to do that.  With the addition of the master vol and the high cut circuit its really an amazing amp.  I have kept tweaking mine and it just gets better. 

Unless you're going to use the amp with a very good reactive load or an Airbrake, I would seriously recommend adding the master volume to it.  I've been recording with this amp and have found I can get all tones from clean to crunch to searing solo leads just from the guitar volume pot - fab! 

The high cut is something recommended to me by another builder over at ampgarage forum. Its great to be able to use lots of high frequency stuff early in the preamp, then smooth it out with the high cut control.  Despite being very different to an AC30 it reminds me of some of Brain May's solo tones. Equally it can give you plexi on steroids tones too.  Some builders remove the presence circuit completely and ground the phase inverter, but I just wired in a fixed value resistor to provide some power amp negative feedback when I added the high cut control.  

Theres a ton of information on TW's and Dumbles also over at Ampgarage.com if you haven't already found it. There head cab plans too if you need them - either to build it yourself or to give to a woodworker etc. 

I'm planning on making another amp identical to this circuit but with a more traditional Express cherry cabinet.  I will definitely build in the same mods as this amp. 

Let me know how you get on - it seems there aren't many people into these amps around ! 

@Keefy - I ned to wrap my head around designing it in Inkscape before I can send the faceplate order to @Modulus_Amps  !! 

I'll put up a clip once I work out how to do that. 

Modulus_Amps

PeteC said:

Hi @Keefy ;



Having used both eyelets and turrets I find eyelets much easier to work with. Turrets certainly look better and give you that "Hiwatt engineered" feeling, but can be a bugger to get good reliable solder joints on sometimes.  Ive done too much fault finding with them tbh.  Eyelets are much easier when it comes to modding and making quick changes too. 

I prefer turrets, but the reason I suspect you have had issue with them is that most retailers now only sell the Asian made turrets that are nickel plated, They tarnish before they have even left the factory!

I sell and recommend silver plated turrets - I also have the nickel ones because some people just don't want to pay the extra, Other good alternatives are the old keystone turrets that are either silver or tin plated and can be bought from mouser for a pretty penny or the RS castellated turrets are tin plated and much easier to solder onto. Those are the ones I use if I run out of silver turrets.

Eyelets are easy though and cheaper, smaller amount of metal to heat up which helps with soldering, but I have seen some proper bodge jobs when the builder has run out of hole space.

@PeteC did you glue all the filter caps down like Ken or mount them on a board. I want to do a kit for these amps but I think the glued down solution is not something I really want to recommend.

PeteC

Hi @Modulus_Amps      Sorry for the slow reply - been a busy week.    When I built this one I did glue all the filter caps down using the strongest trade silicone I could find. Certainly seems pretty solid , but after many years who knows?  I guess it probably wouldn't do for commercial standards though and a daughter board like the dumble-style might be a better bet.  

If you decide to do do a kit would you be able to incorporate possible mod options like MV, fast/gradual split plate load ( Komet-style ) and high cut etc ?   I guess the user could use the presence panel cut out for either presence or Hi Cut controls anyway.   I'd think I would be happy to buy and road-test such a kit. 

As far as turrets and eyelets go - yes, that makes sense. I probably had some bad experience with poorer turrets, but even so I find soldering onto eyelets easier personally.  However, for modding and component changes once an amp is built I think turrets are easier than eyelets !    For my next Express type build I have been looking for the "flea clips" that Ken used in the original TW's. I have found some similar but not identical, and I do think they would make building and subsequent modding quite a bit easier - certainly than eyelets. 

PhilKing

PeteC said:

As far as turrets and eyelets go - yes, that makes sense. I probably had some bad experience with poorer turrets, but even so I find soldering onto eyelets easier personally.  However, for modding and component changes once an amp is built I think turrets are easier than eyelets !    For my next Express type build I have been looking for the "flea clips" that Ken used in the original TW's. I have found some similar but not identical, and I do think they would make building and subsequent modding quite a bit easier - certainly than eyelets. 

Hi @PeteC ;, I'm sure you saw these on the internet, https://www.mouser.com/ProductDetail/Keystone-Electronics/1500?qs=jLI%2FJnmL0oDjnUV5lDroCg%3D%3D.

Let me know if you can't get them in the UK, I'm always willing to help out. 

I played an original Trainwreck Express a few years ago and it was incredible (it wasn't for sale, or I would have bought it). It was very loud, but the tone was awesome.  I kick myself, because in the 80's I lived a few miles from Ken Fischer's and passed the shop regularly, but never went in to see what was there.   If I'd realized, I would have bought an Express or possibly a Rocket back then.

Modulus_Amps

PeteC said:

Hi @Modulus_Amps      Sorry for the slow reply - been a busy week.    When I built this one I did glue all the filter caps down using the strongest trade silicone I could find. Certainly seems pretty solid , but after many years who knows?  I guess it probably wouldn't do for commercial standards though and a daughter board like the dumble-style might be a better bet.  

If you decide to do do a kit would you be able to incorporate possible mod options like MV, fast/gradual split plate load ( Komet-style ) and high cut etc ?   I guess the user could use the presence panel cut out for either presence or Hi Cut controls anyway.   I'd think I would be happy to buy and road-test such a kit. 

As far as turrets and eyelets go - yes, that makes sense. I probably had some bad experience with poorer turrets, but even so I find soldering onto eyelets easier personally.  However, for modding and component changes once an amp is built I think turrets are easier than eyelets !    For my next Express type build I have been looking for the "flea clips" that Ken used in the original TW's. I have found some similar but not identical, and I do think they would make building and subsequent modding quite a bit easier - certainly than eyelets. 

If/When I do a kit it will just the the standard circuit. I do build them with the cut control and fast/slow switching too though, The fast/slow switch is a great mod - Never tried a master volume on one, I tend to think the brutal volume is all part of the experience and I am lucky enough to have the space to crank amps!

PeteC

Thanks @PhilKing - i think i have found the right ones and the correct board too.  Sounds like a “near miss” on that original Trainwreck ! 

@Modulus_Amps    Ha !  Nice to be able to crank em up.  It was one of the reasons i moved to the countryside !!  Still, having the master is a good option for sessions and recording.   It does sound best wide open though I have to admit