Always looking for a better way/material. I checked the West System and Epotec web sites for technical info. Found some. Unfortunately, the two products report mostly different parameters of their characteristics. Hardness was the one that appears to be measured in the same manner (at least the units are stated to be the same): Shore D Hardness for Epotec 301 is 81. Shore D Hardness for West System was 80 after one day and 83 after two weeks. The time after cure for the Epotec was not reported. From these values, I would suggest that the hardness of the two products is similar. Viscosity: Epotec 301 reports "Vicosity @ 23C is @100rpm 100-200 cPs". West System reports "Mix Viscosity @ 72F (cPs) is 725-975". I suspect the rpm the product is stirred at makes some difference. It was not stated exactly how the West System was measured. These numbers appear to suggest that the West System resin is more viscous than the Epotec, but I'm not sure about that. Epotec also makes a product #377. Compared to the #301, it is only slightly more viscous (150-300 cPs), has a Shore D Hardness of 92 (#301 is 81) and has a Lap Shear Strength of 2700 psi (#301 is 1700 psi). Bottom line? Not clear whether West System or Epotec products are better suited to piano work. It appears that the Epotec #337 may offer increased strength/hardness over their #301. Anyone ever play around with both or all three of these products? Terry Farrell ----- Original Message ----- From: "gordon stelter" <lclgcnp@yahoo.com> To: "Pianotech" <pianotech@ptg.org> Sent: Tuesday, November 05, 2002 10:10 AM Subject: Re: Bridge Tops & Epoxy > The Epotek 301 is nearly water-thin to begin with, and > much harder when cured than West's ( which is great > for block fitting or soundboard cracks when used with > the colloidal silica and sawdust/coloring agents ). I > dropped a drop on a piece of 3/4" thick glass once. > When scraped off, it took out a crater!!!!!! > Wafting over it with WARM (not hot!) air is to > make it even less viscous, so that it really > penetrates the bridge, and does not leave it looking > "candied". Yes, the bridge WILL look finished, perhaps > a bit more than if one used straight shellac: but > that's OK with me, when I consider that it is now > impervious to moisture, and is impregnated with a > substance which, due to its denseness will transmit > vibrations beter than the wood itself. I like my work > to be neat, but maximum tonal production and > durability supercede cosmetic tradition, in my book. > And if its still too shiny, I suppose one could > go at it with a gray Sctch-brite pad and brass detail > brushes for a "satin finish". > Gordon > > --- Farrell <mfarrel2@tampabay.rr.com> wrote: > > Heat activated? What exactly are you describing > > here. > > > > Most any epoxy will cure more quickly when heated > > and most any epoxy will decrease in viscosity when > > heated. Are you describing something beyond that? > > > > I use West System epoxy. I don't know exactly how > > the two viscosities compare. West System is about > > the same viscosity as most pancake syrups. I have > > used it on bridge pins with great success. > > > > Terry Farrell > > > > ----- Original Message ----- > > From: "Alan R. Barnard" <mathstar@salemnet.com> > > To: "Pianotech" <pianotech@ptg.org> > > Sent: Monday, November 04, 2002 10:46 PM > > Subject: Re: Bridge Tops & Epoxy > > > > > > > Hmmm... very good. Gordon (or LIST), do you have a > > new source for Epotek > > > 301? McCall's is out of business now, and my > > stock, though refrigerated, is > > > pretty old. Are there other real-thin, heat > > activated epoxies out there? > > > > > > Alan Barnard > > > Salem, MO > > > > > > > > > ----- Original Message ----- > > > From: "gordon stelter" <lclgcnp@yahoo.com> > > > To: "Pianotech" <pianotech@ptg.org> > > > Sent: Monday, November 04, 2002 6:54 PM > > > Subject: Re: Bridge Tops & Epoxy > > > > > > > > > > Hi Terry, > > > > I got fabulous results on my last bridge by > > > > 1)Removing old graphite from bridge with little > > brass > > > > brush and lacquer thinner. 2) Pulling, then > > gluing in > > > > the pins with Epotek 301 and spreading the > > squeeze-out > > > > across the bridge top with a brush while wafting > > from > > > > afar with a heat gun to thin it ( all done in a > > very > > > > warm room, too, with very low humidity ). > > > > When thoroughly dry and after soundboard > > > > finishing, etc., flatten out and take the > > "nose-shine" > > > > off the bridge top epoxy by scraping with the > > edge of > > > > a single edge razor. This is very easy and > > accurate. > > > > When it is nice and flat and dull looking > > and > > > > uniform, take a pencil and rub it. The dulled > > epoxy > > > > LOVES graphite, and will soon be nice and shiny > > and > > > > silvery-black and neat! Looked first-class! A > > pencil > > > > is a lot easier to control than a brush with > > black > > > > stuff on it. > > > > Thump > > > > > > > > --- Farrell <mfarrel2@tampabay.rr.com> wrote: > > > > > Task: New bridge tops or refurbished (new > > pins, > > > > > renotch). Our preference is to set the pins in > > epoxy > > > > > in either case. Some epoxy will ooze out the > > top of > > > > > the bridge pin hole. You need to clean that > > up. That > > > > > will mess up the nicely dagged top. Is > > painting the > > > > > dag on the bridge top AFTER installing bridge > > pins > > > > > the only way to do this? I'm such a sloppy > > artist > > > > > :-( What to do? > > > > > > > > > > Terry Farrell > > > > > > > > > > > > > > > > > _______________________________________________ > > > > > pianotech list info: > > > > https://www.moypiano.com/resources/#archives > > > > > > > > > > > > > > __________________________________________________ > > > > Do you Yahoo!? > > > > HotJobs - Search new jobs daily now > > > > http://hotjobs.yahoo.com/ > > > > _______________________________________________ > > > > pianotech list info: > > https://www.moypiano.com/resources/#archives > > > > > > _______________________________________________ > > > pianotech list info: > > https://www.moypiano.com/resources/#archives > > _______________________________________________ > > pianotech list info: > https://www.moypiano.com/resources/#archives > > > __________________________________________________ > Do you Yahoo!? > HotJobs - Search new jobs daily now > http://hotjobs.yahoo.com/ > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives
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