Return-Path: Sender: (Marvin Kaye) To: lml Date: Sun, 31 Aug 2003 18:32:44 -0400 Message-ID: X-Original-Return-Path: Received: from tomts26-srv.bellnexxia.net ([209.226.175.189] verified) by logan.com (CommuniGate Pro SMTP 4.1.3) with ESMTP id 2562542 for lml@lancaironline.net; Sat, 30 Aug 2003 10:33:02 -0400 Received: from computer ([206.172.96.75]) by tomts26-srv.bellnexxia.net (InterMail vM.5.01.06.04 201-253-122-130-104-20030726) with SMTP id <20030830143254.ZNXN7257.tomts26-srv.bellnexxia.net@computer> for ; Sat, 30 Aug 2003 10:32:54 -0400 Reply-To: From: "Gary Rodgers" X-Original-To: Subject: cabosil/micro balloons X-Original-Date: Sat, 30 Aug 2003 10:32:49 -0400 X-Original-Message-ID: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0004_01C36EE2.0F0F6FC0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.6604 (9.0.2911.0) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 Importance: Normal This is a multi-part message in MIME format. ------=_NextPart_000_0004_01C36EE2.0F0F6FC0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Most of the builders seem to classify and associate 'micro balloons' as if there is only one type/product. In fact, the micro balloons (glass spheres) can be had in varying wall thickness, all the way from the very thin that most are familiar with, to actually solid spheres. The heavier the wall, the stronger they are, harder to sand also. Hollow spheres can be had with specific gravity ranges from .14 to .48, and can range from being able to stand working pressures from 250 psi up to 3000 phi (not including and contribution from the resin). A main advantage to using 'fillers' such as glass spheres is for the purposes of reducing the resin quantity which in turn reduces the expansion/contraction/shrink of material. So if you have to repair an area that is to be finished and exposed, or fill in something, it is a good idea to try and reduce the resin content as much as possible. Another product that I have mentioned in the past is ceramic spheres. Ceramic spheres are usually in the range of ~.8 specific gravity and have working pressures from ~1500 phi to 4000 phi. These are usually processed by being separated out of fly ash by floatation. Again, they can be had at various wall thicknesses/density and are stronger than the glass spheres. There seems to be a better interfacial bond between the resin and the ceramic than with the glass as well. The ceramic, while being somewhat heavier, definitely gives a harder surface. Personally, I prefer to use the ceramic spheres, and instead of using the 'flox', which I believe are cotton fibers, I prefer to use milled fibers. This is ground fiber glass fibers, and can be purchased in various fiber lengths; such as 1/32", 1/16", 1/8". I often use a combination of the ceramic spheres and milled fibers for structural purposes. Cabosil/fumed silica is often misunderstood as being a 'light weight filler'. It is light in dry bulk density only. Gary R ------=_NextPart_000_0004_01C36EE2.0F0F6FC0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Most of the = builders seem to=20 classify and associate 'micro balloons' as if there is only one=20 type/product. In fact, the micro balloons (glass spheres) can be = had in=20 varying wall thickness, all the way from the very thin that most are = familiar=20 with, to actually solid spheres. The heavier the wall, the = stronger they=20 are, harder to sand also. Hollow spheres can be had with = specific=20 gravity ranges from .14 to .48, and can range from being able to stand=20 working pressures from 250 psi up to 3000 phi (not including and=20 contribution from the resin). A main advantage to using 'fillers' = such as=20 glass spheres is for the purposes of reducing the resin quantity which = in turn=20 reduces the expansion/contraction/shrink of material. So if you = have to=20 repair an area that is to be finished and exposed, or fill in something, = it is a=20 good idea to try and reduce the resin content as much as=20 possible.

Another product = that I have=20 mentioned in the past is ceramic spheres. Ceramic spheres are = usually in=20 the range of ~.8 specific gravity and have working pressures from = ~1500=20 phi to 4000 phi. These are usually processed by = being separated=20 out of fly ash by floatation. Again, they can be had at = various wall=20 thicknesses/density and are stronger than the glass spheres. There = seems=20 to be a better interfacial bond between the resin and the ceramic than = with the=20 glass as well. The ceramic, while being somewhat heavier, = definitely gives=20 a harder surface.

Personally, I = prefer to use the=20 ceramic spheres, and instead of using the 'flox', which I believe are = cotton=20 fibers, I prefer to use milled fibers. This is ground fiber glass = fibers,=20 and can be purchased in various fiber lengths; such as 1/32", 1/16", = 1/8". =20 I often use a combination of the ceramic spheres and milled fibers for=20 structural purposes.

Cabosil/fumed = silica is often=20 misunderstood as being a 'light weight filler'. It is light in=20 dry bulk density only.

Gary = R

------=_NextPart_000_0004_01C36EE2.0F0F6FC0--