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Restoring the first Pye HF25

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So after doing a lot of research on how to go about restoring the looks of my as yet untested pair of HF25 tube mono blocks and purchasing absent parts and tubes, the job with the first one got underway a few days ago. To start, all the old lightblue paint had to come off, a solution had to be found to re-apply the black legends and the darkblue aluminium legendplates (2 on each amp), had to be reproduced.

The chassis on these amplifiers are aluminium so not much corrosion but the transformer and choke covers were very badly rusted. Three cheers for 3M sanding pads:D

The old blue paint was removed by painting the surfaces with brake fluid and letting it stand overnight - methinks this was some original idea brewed right here in my workshop:)

I'll post some updates as I go along if there's some interest.




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Hi Graham

Thanks for the interest:D

I've had to take a little break with another job but will resume the Pye restore in a few days and will post more pics soon.

The next step will be to remove all the masking tape except that covering the electronic bits inside the chassis. I will also have to desolder the canned capacitors and remove them and then do a lot of re-masking the newly painted transformers and choke, together with all of the tube sockets etc.

The first chassis coat will be grey etch primer for aluminium, then the pale blue "Pye" colour.

After the blue, comes re-applying all the black lettering using laser-printed waterslide film and finally, acrylic clearcoat + hardener to protect the lettering and paintwork.

I also have a Leak Stereo 20 and its matching Point One pre and Troughline 11 FM tuner which will also get this 'treatment' when the Pye's are done.

Regards & good luck with yours. Williamsons are great!

bulgin, any progress on the restoration?

I'm well into getting the Williamson done. Everything is stripped and mostly pained, and we have most of the replacement components. I really need to start a thread because there are some questions looming.


Hi Graham

Sorry about the delay. Yes, there's been progress together with some errr...hiccups as well:D I eventually finished the painting but not before I discovered the paintshop recommended the incorrect type of undercoat for the aluminium chassis. Yes, I took the amp to the shop and pointed out to them the chassis was aluminium but they still supplied etch primer for steel.

I couldn't leave it like that and had to strip everything down to bare metal and start again. At least I could use the steel primer for the transformer and choke covers.

The amp is with a tech for nearly a month now and I must admit I'm worried as he has done quite a lot of work below and can't get any proper output. A very kind diy audio member has offered to check all tubes for me and this is being done as I write.

I will post a few pics in this post so you can see the outcome.

I'm looking forward to read progress with the Williamson.


Hi Graham

Thank you. I used laser-printed waterslide film. The type was 'set' on my computer. Unfortunately, I don't know the brand of film I used as the printshop who printed my artwork supplied the film.

I have since found that shops selling modeling requisites - eg for the model train enthusiasts - also sell the film. I have since bought one sheet of film from a model shop to try out incase I need it for something else but the brand is different to what I used for the Pye amp.

The film from the model shop is branded Microscale Clear Trimfilm, stock # 02-0.

Yes, I did airbrush automotive clearcoat over the lettering. 3 coats in fact and one cannot see any cut marks around the lettering.

Something I learned while having had to do the job twice: The first time, I applied the lettering directly on the lightblue base colour and then painted clearcoat. This looked OK but when I did the job again, I first painted the base coat, then clearcoat and thereafter applied the lettering. Doing it this way, minimised the lettering's cutting edges almost to nothing.

As mentioned above, I was getting a bit worried about the time it is taking to get the amp working. After speaking to the tech yesterday, he told me he has discovered a minor 'discrepancy' in Pye's schematic compared to the wiring inside the amplifier. I'm not sure if I should feel happy with this 'discovery' though.

Your Williamson restore looks incredible!


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This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.