Felt Washer question

[ICLlP]

I've just taken delivery of felt washers, of a couple of different sizes, from www.dawkes.co.uk.

FA88 = 17.5mm outside diameter, 9.5mm hole diameter and 3.2mm thick (white)
GFP10 = 18.0mm outside diameter, 10.0mm hole diameter and 2.0mm thick (green)

Having tried them both on the bearing spindle it is clear that 9.5mm is the correct hole diameter.  I can't see that the outside diameter at 17.5mm would be a problem, though it's bigger than the original's 15.0mm.  Is the excessive thickness going to cause any issues?  The original looks as though it is only 1.0mm thick, so 3.2mm is quite a bit thicker.

[ZM1080]

the 'felt washer' is there (when a drop of oil is added) to stop dirt getting into the top of the bearing (old cars used a similar principle with wire gauze and an oil bath as an air cleaner before the carb). If the felt washer is too thick, it may get caught on the bottom of the platter. Other than that, the dimensions are not critical (except centre hole diameter), although the washer is, IMHO. Don't forget to oil the washer before use.

[macuser]

Hello everybody,

if it is too thick then it might cause an unwanted friction between the platter and the bearing body.
Even the original felt touches it but in a 'gentle' way but with 3 mm it will be squeezed and in the L-78 auto stop mechanism will also be affected.

Have a look at the photograph below



I can't say it's good nor bad but - as always: size matters !

Kind regards
Max

[Marc VdM]

I would just cut it in half, lengthwise.
It will be a bit of fiddly little job to do, but if you use an exacto knife or something similar it shouldn't be a problem.  And some 1.5 mm left, will be ok!

Good luck!

Marc

[ICLlP]

the 'felt washer' is there (when a drop of oil is added) to stop dirt getting into the top of the bearing (old cars used a similar principle with wire gauze and an oil bath as an air cleaner before the carb). If the felt washer is too thick, it may get caught on the bottom of the platter. Other than that, the dimensions are not critical (except centre hole diameter), although the washer is, IMHO. Don't forget to oil the washer before use.

Thanks Bryan.

[ICLlP]

Hello everybody,

if it is too thick then it might cause an unwanted friction between the platter and the bearing body.
Even the original felt touches it but in a 'gentle' way but with 3 mm it will be squeezed and in the L-78 auto stop mechanism will also be affected.

Have a look at the photograph below



I can't say it's good nor bad but - as always: size matters !

Kind regards
Max

Max, I don't recognise your picture.  What's the bit between the felt washer and the bottom of the platter?

[bush baby]

If you mean the bit of wire bent into a right angle, that is a trip found on a GL78 which makes the auto-stop feature work.

[ICLlP]

I would just cut it in half, lengthwise.
It will be a bit of fiddly little job to do, but if you use an exacto knife or something similar and it shouldn't be a problem.  And some 1.5 mm left, will be ok!

Good luck!

Marc

Thanks Marc.  Maybe I'll give that ago, but it does sound really fiddly!

[ICLlP]

If you mean the bit of wire bent into a right angle, that is a trip found on a GL78 which makes the auto-stop feature work.

I don’t just mean the wire, but also the bit it’s attached to. As well as the wire there appears to be an aluminium washer and a tapered brass bit (to which the wire is attached) between the bottom of the platter and the felt washer.  Is this all part of the auto-stop mechanism of the L78?

[macuser]

Ok, I will try to clear up things.

here are the platters of L-75 (left) and L-78 (right). Imagine the next thing that comes is the felt ring. If you put a felt with 3 mm height in, then I guess the platter will be lifted a bit.
If it is to much the wire won't be able to trigger the stop mechanism at the end of the record (Only with the L-78). A side effect would be that the squeezed felt causes also to much friction then.



hope this helps

Kind regards
Max

[ICLlP]

Many thanks Max. Now I understand.