Copying rare vintage radio knobs.

[Retired]

Hi,

I'm rained off; its another black hole and its cold so as I can't continue with my coffered ceiling I thought I'd spend a bit of time and add the story of how I made a set of wooden knobs for a vintage radio forum member who posted asking if anyone had some of these rare knobs?

Easy job and done in a few minutes? Read on. These knobs had to be octagonal in shape and any deviation on the flats would be painfully obvious so a lot of accuracy was required not only to get all the flats the same size but the front turned sections also needed to be concentric with the axis. I was supplied the only original knob the member had and set about carefully measuring it. Next I used "emachineshop" CAD to draw the shape allowing me to print out white paper templates which in turn were cut out using a pair of scissors.

Looking through my stock of hardwood I found a suitable length of dense tropical wood; species unknown but it would do. This was cut to size and the blanks marked out also their hole centres. The blind holes were bored axially in the big drill press using a 12mm Forstner bit ideally suited for such work but taking care not to go too deep and break through because the blanks would each be subjected to woodturning.

Radio knobs are cross drilled and tapped to accept a grub screw this being the means of securing the knob onto the chassis spindles. Brass round bar stock was selected; cut into lengths then faced and bored in the big Colchester Triumph lathe I owned at the time; the lathe an overkill big style being 3 phase running a 5hp motor. These brass inserts were then roughed on their diameter and in turn glued and pressed home into the wood blanks. Whilst the blanks were still connected together they were cross drilled and tapped at 4BA to accept grub screws. The blanks were then roughed out on the bandsaw taking care to leave extra material. Then each blank had a paper template attached using double sided self adhesive tape.

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I had a home made 4" belt sander and this proved ideal for bringing the blank flats down to the template lines firstly with a coarse belt then fine sanding. This took care of the inserts and flats. Next to do was the turning; I mounted a Jacobs chuck in my Record Power DML24" woodturning lathe and into this chucked a short 1/4" diameter steel rod; each blank was then attached in turn using a grub screw securely to the rod and carefully turned matching the pattern of the original knob and sanded smooth under power.

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The new knobs were then stained in Jacobean Oak and finished with French Polish (Shellac); the pictures show the original knob together with the new knobs; I didn't attempt to distress the new knobs they being honest copies. This small project was a delight for me to do but took quite a few hours to accomplish. I packed and posted the original and new knobs to the forum member with my compliments and he was absolutely delighted to receive them to complete his radio restoration. I gained a lot of personal satisfaction out of making the knobs and this was reward enough for me. I find on forums there are many genuine like minded people and it's good to be able to help each other out. This project fell just at the right time because usually I'm bogged down with jobs. I hope this is of interest as its unusual.

Kind regards, Col.

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Finished knobs.jpg (234.7 KiB) Viewed 4533 times

[dewaltdisney]

Nice job Colin, can you make me a new knob too?

DWD

[Rorschach]

Blimey they look good, It took me a good few seconds to spot the original!

[wine~o]

Nice job Colin, can you make me a new knob too?

DWD

*TSK* Dwd, It is Billy goats job to lower the tone...

Nice work, Col...

I wonder how they made the original knobs? would they have been Bakelite ?

[kellys_eye]

Superb skills on show (yet again) Col. You must get a fantastic feeling of achievment when completing that kind of work and the recipient was rightly ecstatic at getting such quality replacements. Well done.

Your work is sheer inspiration.

[merlin50]

Proper job nothing better than restoring old things

[thescruff]

Real skills, thinking outside of the box at its best.

[Retired]

Hi,

Thanks dwd; if I'm interested I can make most things.

Thanks Rorschach; I like to do my best after all it only takes a bit more effort to do a good job than a mediocre job when the same materials are used; these days it's all rush and panic but in my little world I find I can finally relax and enjoy doing a job just for the love of doing it.

Good question wine~o; many radio knobs were in fact made of Bakelite as indeed were many radios such as the excellent round Ekco series which still command high prices. In this instance though the original knobs were wood hence I copied the original as seen in the picture. Some vintage radios such as Cossor had metal knobs and these could be lethal should the chassis develop a fault and become live; I've had vintage radio chassis on my bench with live very high voltages and it is a must when working on an unknown chassis never to pick it up with both hands whilst power is applied or it could be the last thing ever done; I always ran unknown chassis through a 100W light bulb; if the bulb lit up brightly it was time to switch off and find the short? I also used an isolation transformer for my safety.

Praise indeed k-e which is much appreciated; thank you; yes I do get a personal buzz out of such successes; many times I get so involved in projects I don't really notice the progress but once completed and I stand back I think how the heck did I manage to do that; I'm no one special and lots of the knowledge I have has been hard won because I'm not the sharpest tool in the kit by any means but I do have a great deal of confidence and patience to make up for my ignorance.

Thanks merlin50; I must agree that restoring old things is a most pleasant pastime with something to show for it at the end. Once I do restore something then the bubble bursts for me and I lose interest because its the doing and problem solving which drives me forward rather than ownership; I've sold the bulk of my radio collection and cleared out my wireless shack because I felt I had gone as far as I could with vintage radio restorations; I could restore a wooden radio cabinet easily and I progressed to winding mains transformers etc; I'm now back to my love of woodworking and playing with my many toys.

That's good of you thescruff; my Kaizen training is showing through where I was taught to break jobs down into their basics although I have been trained by some top engineers mostly as an apprentice with the National Coal Board and these skills are always with me. If something is regarded as beyond repair or cannot be done then this is for me; I don't like run of the mill projects preferring something that will stretch me; I spend many restless nights struggling with problems but if I stick at it I win through usually just at the time when I feel like packing it in? These wooden knobs were an interesting little project but I wouldn't want to make them day in day out otherwise I would quickly become bored. I'll never reach my full potential here in the UK because the weather is so dire.

I don't mind adding other such threads if anyone is interested not just covering radio work.

Thanks again everyone for your kind comments.

Kind regards, Col.

[thescruff]

Go for it Col the more the merrier

[joinerjohn]

A delight as always to read your threads Col. Brilliant little thread in it's own right. Who'd have ever thought that making such a small item would be so interesting.

[Bikergirl]

Interesting thread, and lovely job.
I just wish I had the toys and more to the point the time and space to have a go at bits like this.

[pfb5]

I just wish I had the toys and more to the point the time and space to have a go at bits like this.

Me too, fantastic dedication once again, Col.
______
Paul

[Retired]

Hi,

Thanks thescruff; it's interesting and relaxing for me posting my various stories.

Thanks jj, such small jobs seldom get written up but they can lead to bigger jobs as experience is gained. When I saw the request for help I thought why not have a go at making these knobs because it would be very unlikely anyone had a set of spare knobs of this type and I saw it as a challenge. Such a simple project but for me it involved CAD; hand and machine tools together with some woodturning thrown in. It also kept my head and hands busy which is the most important part for me; it was something totally different for me to do and with the write up others can now do similar jobs where previously they would never have thought of doing it themselves?

Thanks Bikergirl; I've just had a look at your website Sophie wondering how you decided on "Bikergirl" have you had or do you have a bike and if so what details because I'm an ex biker and am still interested in bikes. I've said many times that if I can do something then others can but we are not all equal regarding kit; working space and time all of which are important. I worked at my last stressful job for 24 years but looking back I'm amazed by how much I accomplished regarding jobs and projects in the very little free time I had; Bron and I replaced the entire bungalow and extension roofs in a fortnights holiday; more stress and lots of pressure but we succeeded. The hardest part in any project is making a start; it's very difficult given our climate to leave a cosy space to venture out into the black hole getting a soaking or feeling cold and start handling cold tools and materials but I've done some of my best work in such conditions. I would encourage anyone who is fed up to find something interesting to do; strangely the black hole etc then suddenly disappear; I can become so engrossed in what I'm doing I don't notice how cold I've become until I knock off; occasionally I'll nick myself and don't feel it until I see the material I'm working on become smudged in red; this seldom happens but when it does I receive sympathy from Bron together with a couple of sticky plasters; biscuit and pot of tea then I'm back on the job again. In many ways I'm still a little lad playing with his toys.

Thanks Paul, all it takes is dedication and determination to do similar projects; this knob making project is obviously very small compared to say building a house but for its duration it got me away from the troubles of the world allowing me peace to settle down doing no harm to anyone and to enjoy myself. I can turn sweeping up into a project as I do with many jobs which are regarded as boring; I hope I don't come over as preaching or a smart so and so it's just the way I am being happy and content in my own little world.

Time I made some progress on the coffered ceiling; I've got the heat on in the bedroom so will think I'm working in Miami for a change; life can be so good.

Kind regards, Col.

[Retired]

Very nice work Col

[EJJ150847]

I love making things, wish I had a lathe.

Nice to see your projects, there was a chap on here from Malta, Rotciv, he made some wonderful stuff.


Keep posting your work.


John