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-   -   Baird T5 restoration project. (https://www.vintage-radio.net/forum/showthread.php?t=152005)

bluepilot 3rd Feb 2019 5:18 pm

Re: Baird T5 restoration project.
 
Why not ask the customer what he wants? The more parts you make new, the further you get into "grandfather's axe" territory. ("This is my grandfather's axe. My father replaced the handle and I replaced the head"). A good soak in Cuprinol, Xylophene or whatever should take care of the woodworm if necessary.

FERNSEH 3rd Feb 2019 6:02 pm

Re: Baird T5 restoration project.
 
Hi Stuart,
last week I spoke to the owner of the set and he is agreeable to replacing the side panels if there is any doubt about the condition of the originals. Tongue and groove joints are used to secure the panels into the framework. The hardwood framework is untouched by the worms but the tongues on the panels are a bit chewed up in places.
Interesting to note very little glue was used in the construction of the cabinet. Lots of screws and really tight close tolerance joints to keep everything together. OK, these sets weren't made in vast numbers but nevertheless a lot of investment must have gone into the tooling to make these beautifully constructed cabinets.

DFWB.

Magpie66 3rd Feb 2019 9:15 pm

Re: Baird T5 restoration project.
 
Hi Dave.

Reading the previous posts, I think there will always be doubts about whether the woodworm will return. It would be such a shame to put in all this work only to find a couple of holes in it further down the line. If the eradication of the woodworm could be guaranteed then carry on but I feel the panels need to be replaced.

We have rescued this piece of history so let’s make it last another 80 years.

Anthony

FERNSEH 5th Feb 2019 12:12 am

Re: Baird T5 restoration project.
 
Work on making the new cabinet sides will commence later this week.

Earlier this evening the signal generator was connected to the sound receiver unit. The sound receiver is not a superhet as the vision receiver is, but is in fact a TRF, fixed tuned to 41.5mc/s. The receiver down in sensitivity. Supplying the unit with a channel B1 signal direct from the Aurora gives insufficient output from the loudspeaker. According to the oscilloscope the oscillator in the demodulator is operating at 783kc/s.

DFWB.

Tractionist 5th Feb 2019 9:28 am

Re: Baird T5 restoration project.
 
I'm not surprised that the worm hasn't gone for the hardwood framing ..... softwood [and associated plywood glues] seem to offer the beasties plenty of continuing delight in this particular cabinet!

The sides seem to exhibit plenty of infestation - and as mentioned previously, there seemed to be fresh frass in your original photos' ..... indicating on-going activity.

Under these circumstances, I would definitely replace the sides [and give the framework a good lick of clear Five Star Cuprinol - just for good measure].

It's coming together eh? !!

FERNSEH 5th Feb 2019 10:10 am

Re: Baird T5 restoration project.
 
2 Attachment(s)
"It's coming together eh? !!"

It sure is but there is another part of the cabinet to deal with and that's the control panel. It's an easy part to replicate except for one item, the "TELEVISOR" emblem which must be preserved or an exact copy made.

DFWB.

HamishBoxer 5th Feb 2019 10:17 am

Re: Baird T5 restoration project.
 
I would certainly want them renewing,not worth the risk at all.

davyrocket2 5th Feb 2019 1:17 pm

Re: Baird T5 restoration project.
 
I am sure there that many who are watching this could help with a possible copy or scan of the Televisor Emblem which could be a water base transfer, this is a great restoration as all the others you do with plenty of detail it really amazes me how you and others keep finding what seem to be the holy grail of probaly tvs which most would have thrown away but you David resurect and bring back to life fascinating .P.S,I have meant to contact you on another matter is it ok to PM you I met you at mikeys swap meet regards David

FERNSEH 5th Feb 2019 8:31 pm

Re: Baird T5 restoration project.
 
1 Attachment(s)
A replacement right side panel was made today and test fitted. A few slight adjustments required to achieve a perfect fit.

DFWB.

FERNSEH 8th Feb 2019 8:34 pm

Re: Baird T5 restoration project.
 
1 Attachment(s)
The attachment shows the condition of the original left side panel. After removing the lower batten serious woodworm damage was found. The panel is scrap. A replacement was made today.

DFWB.

mark pirate 9th Feb 2019 10:08 am

Re: Baird T5 restoration project.
 
That is the worst infestation of woodworm I have ever seen :o
A while back I purchased a Pye LV20 in very poor condition (mainly for the CRT).
The base of the cabinet crumbled away to dust, what was left had been hollowed out internally. One good stomp on the top of the cabinet, and it broke in to several pieces!

I disposed of it in my wood stove, I take no chances with it when it is this bad.
Amazingly the chassis was in great shape once properly cleaned, and will be saved for future use.

I bet you are pleased that the hardwood frame is unaffected and can be kept.
:beer:
Mark

FERNSEH 9th Feb 2019 3:43 pm

Re: Baird T5 restoration project.
 
1 Attachment(s)
All the new cabinet parts made so far are assembled together to show the progress I've made with the cabinet reconstruction. Next week I'll turn my attention to the front panel. Lay on new veneers and refit all the detailing parts.

DFWB.

Heatercathodeshort 9th Feb 2019 5:25 pm

Re: Baird T5 restoration project.
 
Aghh David, I see now what you are doing. Is the hole in your T5 designed to fit the base of that sickly coloured ball thing in the background?

Seems a shame to scrap the innards of the original T5 just for it to be replaced by that plastic bomb. John.

FERNSEH 9th Feb 2019 8:34 pm

Re: Baird T5 restoration project.
 
1 Attachment(s)
Quote:

Seems a shame to scrap the innards of the original T5 just for it to be replaced by that plastic bomb. John.
Hi John
It's a Keracolor colour TV set. Likely to be as rare as the Baird T5.

DFWB.

Jac 10th Feb 2019 9:05 am

Re: Baird T5 restoration project.
 
I'd rather have the T5 David :)

Jac

line sync 10th Feb 2019 12:39 pm

Re: Baird T5 restoration project.
 
When I worked at an ex rental tv outlet we hated those sets because you could not stack them on top of one another.
Keep up the good work david and get all that infested wood out of the shop , you don't want any beetles making a home in your other sets.

Robin

peter_scott 10th Feb 2019 3:59 pm

Re: Baird T5 restoration project.
 
The T5s were bad for stacking too.

Peter 8-o

FERNSEH 10th Feb 2019 6:20 pm

Re: Baird T5 restoration project.
 
Quote:

Originally Posted by Jac (Post 1119100)
I'd rather have the T5 David

Hello Jac,
Thankfully the Keracolor thing is a repair job and it won't be in the workshop for long. Real 70s kitsch.

Hi Robin,
rest assured those woodworm infested panels will be burnt.

Quote:

Originally Posted by peter_scott (Post 1119237)
The T5s were bad for stacking too.

Hi Peter,
There'll soon be two T5 sets in the shop. But I better not try stacking them.

DFWB.

FERNSEH 13th Feb 2019 10:37 am

Re: Baird T5 restoration project.
 
3 Attachment(s)
The top CRT display panel hasn't escaped the attention of the woodworms.
So it follows a new top panel must be made to replace the damaged part. Pictures show the first stages of the construction of the new CRT screen panel.

DFWB.

Tractionist 13th Feb 2019 4:35 pm

Re: Baird T5 restoration project.
 
Those beasties do look [hyper] active .... bright clean flight holes and plenty of frass! Exterminate! Exterminate! Exterminate! (God forbid ..... this could migrate to the Tardis!!) :-D

1100 man 13th Feb 2019 9:54 pm

Re: Baird T5 restoration project.
 
Hi David,
I've been following your progress with this restoration with great interest! At least with the cabinet in that bad a state, the decision to replace most parts of it is made rather easier.
It must have been a very satisfying project so far. Of course, when you come to the veneering, things will get even more difficult! Have you much experience of doing this?
Well done on progress so far.

All the best
Nick

FERNSEH 14th Feb 2019 10:35 am

Re: Baird T5 restoration project.
 
2 Attachment(s)
Hi Nick,
fortunately there is not too much veneering work required for this job.
The CRT screen panel, the new control panel and the front panel will need veneering. The side panels are furniture grade plywood and have very nice wood grain patterns. The new panels can be stained and polished before final assembly. The mirror lid is in good condition and requires little attention other than stripping off the old lacquer and a few minor repairs to the veneers.

The screen aperture has a 30 degree chamfer around the edges. That part of the job went well, see second picture. However, things didn't go well when it came to routing out the 5mm recess for the implosion glass. The router tool kinda went wild and ruined the panel. So that panel will join the woodworm damaged parts. Scrap!

DFWB.

FERNSEH 18th Feb 2019 10:09 am

Re: Baird T5 restoration project.
 
It will be possible to repair the damaged CRT display panel but instead I will make a new one which will be constructed from two pieces of 6mm plywood glued together.
I'm now on the lookout for veneer for the front panels.

DFWB.

Hunts smoothing bomb 18th Feb 2019 9:42 pm

Re: Baird T5 restoration project.
 
Great progress David, the skills that you possess in cabinetry I find nothing short of amazing!

This is going to be a super set when finished.

Cheers

FERNSEH 20th Feb 2019 11:20 am

Re: Baird T5 restoration project.
 
2 Attachment(s)
Hi Lee,
The cabinet reconstruction is progressing very well. The control panel is the last cabinet part to be made. I'll attempt to do this later this week. In the meantime let's take a look at the vision receiver. Signals are supplied direct to the mixer, no RF amplifier. This was a common practise in early TV receivers. Because the intermediate frequency is low the four stage amplifier should provide excellent gain. The Mullard TSP4 pentodes have a gm of 4.2ma/V which is a good figure for early television RF pentodes. Because the set employs a large CRT a full wave demodulator is employed in order to avoid a fine dot pattern appearing on the screen. A Mullard 2D4A double-diode is used as the vision detector. A TSP4 is used as the video amplifier.
Positive going video is supplied to the CRT grid via a capacitor. No DC restorer.

DFWB.

ThePillenwerfer 26th Feb 2019 11:31 pm

Re: Baird T5 restoration project.
 
Come on, David, let's have an up-date. The suspense is killing me: have the woodworm eaten you?

FERNSEH 27th Feb 2019 10:02 am

Re: Baird T5 restoration project.
 
"have the woodworm eaten you?" Hi Pillenwerfer,
But they have made a good meal of every plywood panel. The control panel is the last cabinet part to be made and it is proving to be a bit difficult replicate but I will have something show on the forum by the weekend.
The vision receiver and the power supply units are on the bench for servicing. We'll soon find out the intermediate frequency and the passband characteristics of the IF amplifier.


DFWB.

FERNSEH 27th Feb 2019 4:56 pm

Re: Baird T5 restoration project.
 
Testing the power supply unit. The 16mfd reservoir capacitor and the 24mfd main smoothing capacitor were found to be useless so for the time being two 8 + 8 mfd capacitors will be used until the correct components can be found.

Under no load and with only 150VAC supplied from the variac the smoothed HT voltage is 300V. Later today the vision and sound receivers will be connected to the power supply.

DFWB.

ThePillenwerfer 27th Feb 2019 6:03 pm

Re: Baird T5 restoration project.
 
Good to hear that your steadily progressing.

FERNSEH 28th Feb 2019 10:28 am

Re: Baird T5 restoration project.
 
1 Attachment(s)
In fact as the picture shows I've little choice but to make a new control panel.

DFWB.

ekjdm14 28th Feb 2019 10:48 am

Re: Baird T5 restoration project.
 
Wow, only just seen this thread & the first thing that springs to mind is that episode of The Young Ones... "Vivien, eat the telly!" :o

Right, now I've got that off my chest I shall go back and continue reading. It looks like one heck of a project and I doff my hat to you for taking it on.

beery 1st Mar 2019 2:09 am

Re: Baird T5 restoration project.
 
1 Attachment(s)
Hi David,
I'm loving the progress by the way.
I've uploaded a photo of how the vision unit would have looked with the original capacitors. The electrolytics in the one you are restoring have been very neatly fitted, so I would say definitely a manufacturer's post war overhaul.

Another thing I have noticed by looking at photos of other surviving T5 sets is that sometimes the speaker is on the other side of the cabinet. I can't see any reason why moving it to the other side would help really, so maybe it is just random...

Cheers
Andy

FERNSEH 1st Mar 2019 11:47 am

Re: Baird T5 restoration project.
 
2 Attachment(s)
Today's report is about the good progress I'm making with the sound and vision receiver units. The oscilloscope trace shows the negative going video present at the grid of the TSP4 video output valve. Despite having no RF amplifier the vision receiver has high gain. It has been established that the vision IF amplifier is aligned to the upper sideband which means there is a deep "trough" between the vision and sound passbands. The vision IF is 13mc/s, much higher than I thought it would have been.
Much more work needs to be done on the vision receiver but the results so far are very encouraging.

DFWB.

FERNSEH 2nd Mar 2019 4:21 pm

Re: Baird T5 restoration project.
 
2 Attachment(s)
Today the new control panel was test fitted.

The panel is canted back 35 degrees which made it necessary to adjust the angle of the cutting disc on that scary saw bench.

DFWB.

Magpie66 7th Mar 2019 8:21 pm

Re: Baird T5 restoration project.
 
Hi Dave.

Got one of those saws myself,not my favourite tool.

Nice to see your progress on the T5. I remember you saying that you were enjoying this restoration. Hope the problems you have encountered haven’t changed your mind.

Keep up the good work, Anthony.

FERNSEH 7th Mar 2019 10:24 pm

Re: Baird T5 restoration project.
 
2 Attachment(s)
Hi Anthony,
The restoration of the Baird T5 is progressing well. Just two more jobs to do before the wood veneers are applied to the surfaces of the cabinet front panel, the control panel and the CRT screen panel.
First task to do this weekend is make the specially shaped beading fitted between the control panel and the upper panel, see the attached pictures. It might be possible to use ordinary stock beading available from B & Q. Again, the saw bench will cut out the 30 degree chamfer.

The second task is to make the cut out in the front panel for the door to access the timebase controls.

DFWB.

FERNSEH 14th Mar 2019 9:20 pm

Re: Baird T5 restoration project.
 
1 Attachment(s)
The cut out in the front panel for the timebase controls door was made today.
The front panel is now ready for the surface veneers to be applied.

DFWB.

beery 15th Mar 2019 1:26 am

Re: Baird T5 restoration project.
 
I see you have included a cat sized fire escape via the speaker aperture...

FERNSEH 27th Mar 2019 12:40 pm

Re: Baird T5 restoration project.
 
1 Attachment(s)
All the interior surfaces of the cabinet are matt black and of course the best paint for the job is that used for blackboards.

DFWB.

FERNSEH 2nd Apr 2019 2:37 pm

Re: Baird T5 restoration project.
 
1 Attachment(s)
Decisions, Decisions. The attachment shows two CRT support panels, the one on the left is the original and the other is the newly made replica.
The CRT panel was the only plywood part in the set that wasn't totally destroyed by woodworm, only one corner of the panel had been invaded by the worms.
So, the question is, in order to maintain some originality should the refurbished panel be used in the reconstruction or, should we play safe and fit the replica part?

DFWB.

Nuvistor 2nd Apr 2019 3:26 pm

Re: Baird T5 restoration project.
 
Play safe David, be a disaster if any worms remain and start on all that great woodwork you have done.

FERNSEH 2nd Apr 2019 4:18 pm

Re: Baird T5 restoration project.
 
Hi Frank,
That's right we know from past experience that those worms can re-emerge long after a state of dormancy.

Fit the new panel. It's identical to the original.

https://www.wisepropertycare.com/ser...tle/lifecycle/

DFWB.

peter_scott 2nd Apr 2019 4:50 pm

Re: Baird T5 restoration project.
 
Play safe but retain the reconstruction with the set.

Peter

FERNSEH 2nd Apr 2019 7:28 pm

Re: Baird T5 restoration project.
 
"Play safe but retain the reconstruction with the set."

Hi Peter, All the new parts made for the T5 are directly interchangeable with original pre-war parts.

DFWB.

line sync 2nd Apr 2019 7:55 pm

Re: Baird T5 restoration project.
 
Play safe david and fit your newly made one.
You never know there could be some hibernating in the original board.

Robin

beery 3rd Apr 2019 7:54 am

Re: Baird T5 restoration project.
 
Hi David,
I agree with others, do fit the replacement part.

Quote:

Originally Posted by FERNSEH (Post 1133754)
Hi Frank,
That's right we know from past experience that those worms can re-emerge long after a state of dormancy.
DFWB.

I seem to be reminded of an Ekco from the past...


Cheers
Andy

Freya 3rd Apr 2019 8:11 am

Re: Baird T5 restoration project.
 
With all the work so far, it would be a shame to see it attacked again. Will you spray with preventative treatment prior to the veneering ?

FERNSEH 3rd Apr 2019 9:27 am

Re: Baird T5 restoration project.
 
Quote:

Originally Posted by Freya (Post 1133911)
With all the work so far, it would be a shame to see it attacked again. Will you spray with preventative treatment prior to the veneering ?

Hi Steven,
I believe modern plywood uses non animal sourced glues to bond the laminar sheets together and is less liable to woodworm invasion, but nevertheless it will be a good idea to protect the newly constructed cabinet from any future woodworm problems.

Rest assured the new CRT support panel will be fitted in lieu of the original part.

DFWB.

mark pirate 3rd Apr 2019 10:46 am

Re: Baird T5 restoration project.
 
Quote:

Rest assured the new CRT support panel will be fitted in lieu of the original part.
Very glad to hear that David, I have had a set ruined by woodworm while in storage, it appears to have spread from the shelf unit it was stored on.
Both the cabinet base & shelf had to be burnt.

Thankfully it was in my (concrete) garage, rather than my house!
Looking forward to seeing the results of the veneering, keep up the good work.
:beer:
Mark

Argus25 3rd Apr 2019 11:41 am

Re: Baird T5 restoration project.
 
Quote:

Originally Posted by FERNSEH (Post 1125011)
The vision IF is 13mc/s, much higher than I thought it would have been.
Much more work needs to be done on the vision receiver but the results so far are very encouraging.

Looking at the signal on the video output valve it shows a limited HF response, as seen by the rounded corners on the sync pulses. It could be the capacitance of the scope probe on a high Z part of the circuit, making that look worse than it really is.

Regarding the "worm" do you know what sort of species it is ?

Many Bora beetles are insects, if they are, their chitinous exoskeletons dissolve in hydrocarbon solvents.

So, you can dissolve their bodies (melt them like the wicked Witch in the Wizard of Oz) simply by soaking/painting the timber with Terpentine. Also, there is the opportunity to paint and soak the timber panels with insecticide (not the inept green environmentally friendly type that is hopeless and doesn't work, but the real toxic deal).

If there are any residual wood destroying life forms there which could include insects or fungi, you should be able to exterminate them completely. Also , another option is to slowly raise the temperature of the wood to a value that is incompatible with life, around 125-135 deg C over 1/2 hr would do it without too much damage to the timber.


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