Removing Cambridge International knobs - UK Vintage Radio Repair and Restoration Discussion Forum

georgeek · 21st Mar 2016, 10:28 pm

The service sheet for my Cambridge International says I need to pull off the knobs to remove the chassis, which is obvious on inspection

The thing is that they don't pull off even with a really good pull. Any more force and I think I may damage them....

Any tips much appreciated.

60 oldjohn · 21st Mar 2016, 10:52 pm

Lever them off from inside (end of knob) with a large screwdriver and a block of wood of a suitable size to take up slack with the chassis. DO NOT apply force to the wood case or the large part of knob. I don't think there are grub screws on the PE80 but just check in case One of the knobs may be on a shaft extension, just slacken screw on that one and withdraw knob with shaft still attached.

John.

Goldieoldie · 21st Mar 2016, 11:11 pm

If you can slither a thin piece of cloth behind the knob then gather it up so the pull load is spread evenly .Ive used this method successfully
Cheers Pete

60 oldjohn · 22nd Mar 2016, 9:52 am

I often use Pete's method, where room is tight but in this set you can with care use a approximately 25mm x 25mm say 30cm long piece of wood with a screwdriver taking care not to catch any of the fine control wires. One in place do not move the wood just the screwdriver. The shaft extensions I was thinking of are for the Hacker RV14 volume control not the PE80.

John.

georgeek · 25th Mar 2016, 5:09 pm

Thank you!

21st Mar 2016, 10:28 pm	#1
georgeek Triode Join Date: Jun 2012 Location: East Sussex, UK. Posts: 47	Removing Cambridge International knobs The service sheet for my Cambridge International says I need to pull off the knobs to remove the chassis, which is obvious on inspection The thing is that they don't pull off even with a really good pull. Any more force and I think I may damage them.... Any tips much appreciated.

21st Mar 2016, 10:52 pm	#2
60 oldjohn Dekatron Join Date: Dec 2004 Location: East Yorkshire, UK. Posts: 3,987	Re: Knobs Off? Lever them off from inside (end of knob) with a large screwdriver and a block of wood of a suitable size to take up slack with the chassis. DO NOT apply force to the wood case or the large part of knob. I don't think there are grub screws on the PE80 but just check in case One of the knobs may be on a shaft extension, just slacken screw on that one and withdraw knob with shaft still attached. John. Last edited by 60 oldjohn; 21st Mar 2016 at 10:56 pm. Reason: added last line

21st Mar 2016, 11:11 pm	#3
Goldieoldie Octode Join Date: Jul 2014 Location: Petersfield, Hampshire, UK. Posts: 1,043	Re: Knobs Off? If you can slither a thin piece of cloth behind the knob then gather it up so the pull load is spread evenly .Ive used this method successfully Cheers Pete

22nd Mar 2016, 9:52 am	#4
60 oldjohn Dekatron Join Date: Dec 2004 Location: East Yorkshire, UK. Posts: 3,987	Re: Removing Cambridge International knobs I often use Pete's method, where room is tight but in this set you can with care use a approximately 25mm x 25mm say 30cm long piece of wood with a screwdriver taking care not to catch any of the fine control wires. One in place do not move the wood just the screwdriver. The shaft extensions I was thinking of are for the Hacker RV14 volume control not the PE80. John.

25th Mar 2016, 5:09 pm	#5
georgeek Triode Join Date: Jun 2012 Location: East Sussex, UK. Posts: 47	Re: Removing Cambridge International knobs Thank you!