[CAUT] VS Profelt

[Fred Sturm]

	A couple words of caution might be in order. This is not a "magic  
formula." The swelling of the felt ("re-fluffing" it) is due to the  
action of water content in the formula. The alcohol in the formula  
helps the water penetrate. In use for action centers, this is  
precisely the same as using a formula of water and alcohol, except  
that we don't know the proportions in VS Profelt (and the Profelt has  
some lubrication function - but the bigger result will be due to  
"shrinking of felt" as in simply applying a formula of alcohol and  
water).
	This is not meant to discourage the use of Profelt, simply to urge  
that it be used "with eyes wide open." I do realize that it is  
different from just alcohol and water in that it has a lubricant, and  
apparently some kind of conditioner. Silicone lubricant is probably  
effective and probably has no negative side effects in this  
application. Whatever may be used as a conditioner may possibly have  
side effects in some situations.
	Re-swelling of felt in itself is a reversal of the packing due to  
wear. However, it can be overdone. Felted cloths, especially bushing  
cloth, have been made dense with considerable trouble, processing  
including heat and pressure. It is quite possible to "over-reverse"  
and end up with a felt that is less dense than it was originally.  
Using cauls for key bushings is a somewhat effective way of preventing  
this. For wippen cushions and the like, cauls aren't an option.
	Personally, I find the use of heat and pressure (a clothes iron or  
heated cauls) is a good way to try to keep the felt in a firmly packed  
condition (which means the regulation will be more stable).
	One thing that re-swelling felt doesn't do is reverse wear. Fibers  
that have been broken down and worn away are gone. Lubrication of new  
materials and parts is the best way to have long lasting parts. In  
fact, that is one of the claims of VS Profelt: use it on new felt so  
that its lubrication properties will prolong life and improve  
function. It may be effective in that way. I will find out when I try  
some. Meanwhile, I put my money on powdered teflon and other, more  
concentrated lubricants.
Regards,
Fred Sturm
University of New Mexico
fssturm at unm.edu



On Nov 6, 2008, at 3:17 PM, Paul T Williams wrote:

> Hi Barbara,
>
> I would also like to know about VSP for center pin bushings!  I have  
> only used it for key bushings and wip cushions.  Didn't do quite as  
> good a job on the wip cushions, but did help...the cushions were  
> really old and badly dented.  Probably should have replaced,  
> but...ya know...budget stuff.

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