Here's some info from an engineer at Franklin, maker of Titebond. Mr. Evans also worked at Baldwin for a time. In light of his comments I wonder in these instances of perceived creep whether the movement is a result of creeping glue, or a result of a poor methodology - poor joint construction, insufficient glue, too tight clamping, etc. FWIW Alan -- Alan McCoy, RPT Eastern Washington University amccoy at mail.ewu.edu 509-359-4627 ------ Forwarded Message From: iasts <IASTS at FranklinInternational.com> Date: Tue, 11 Dec 2007 09:38:12 -0500 To: Alan McCoy <amccoy at mail.ewu.edu> Conversation: Aliphatic resin creep under load Subject: RE: Aliphatic resin creep under load The aliphatic resins like Original Titebond will creep somewhat over time. They are not recommended for structural applications such as load-bearing beams in buildings etc. Some of the straight PVA products have little creep resistance. Original Titebond will be superior to these products. The topic of creep in PVA adhesives is a common question in musical instruments and particularly pianos. My experience with adhesives to glue ribs, soundboards to rims etc has been in the original manufacturing of the instrument where the choice of adhesive can be related to the process in the factory as much as the end use. I have used PVA products in repairs on my own piano in areas such as a rib that has popped loose at the end. In this case, the PVA worked where the original product (probably UF) obviously did not. I don't have any first hand experience in gluing ribs or bridges onto the soundboard or the soundboard into a rim. My guess is that there are a number of re-builders that use them frequently without problems. Ribs to soundboard would be my biggest worry because of the stresses on the joint and the cross grain gluing. The experience of field technicians that you allude to in your e-mail suggests that it is probably not a problem to use Titebond Original in these applications. Hugh W. Evans Senior Applications Engineer Industrial Adhesives and Sealants Franklin International (800) 877-4583 (614) 445-1555 (FAX) -----Original Message----- From: Alan McCoy [mailto:amccoy at mail.ewu.edu] Sent: Monday, December 03, 2007 1:55 PM To: iasts Subject: Re: Aliphatic resin creep under load Mr. Evans, I would like to be able to forward your message to our piano email list as we are once again having a discussion on aliphatic resin creep under load. There are some who insist that original Titebond creeps, and others who insist that original Titebond doesn't creep under the loads typically found in pianos. If I understand your response below, you would be comfortable using the original Titebond in gluing ribs to a soundboard, or gluing the soundboard to the rim, or gluing a bridge to a soundboard, right? Thanks. Alan -- Alan McCoy, RPT EWU Piano Technician 119 Music Bldg Cheney, WA 99004 359-4627 (509) 999-9512 weekdays amccoy at mail.ewu.edu > From: iasts <IASTS at FranklinInternational.com> > Date: Wed, 27 Jun 2007 15:12:31 -0400 > To: Alan McCoy <amccoy at mail.ewu.edu>, "Goodwin, Joseph" > <JosephGoodwin at FranklinInternational.com> > Conversation: Aliphatic resin creep under load > Subject: RE: Aliphatic resin creep under load > > Alan, > > Prior to coming to Franklin in 1985, I worked for 15 years in a materials > laboratory at Baldwin Piano in Cincinnati and did a fair amount of research > with many different adhesives including a creep test that I developed. > > PVA type products are generally not designed for structural uses such as > horizontal beams etc used in building. I have found that many of the > aliphatic resins do work well in other areas where creep would be a concern > and have seen them used in many musical instruments. Our Titebond Extend > would be a good example of this type of product particularly at elevated > temperatures. Hide glues are good especially if it is dry. Both liquid and > hot hide glues are very sensitive to moisture including high humidity. I have > seen crosslinking PVAs used on applications like ribs to soundboards > apparently without trouble. Urea (plastic) resins are used there as well. > > I am not sure if I have answered your question or not, but I would feel > comfortable with an Aliphatic resin or hide glue for some of the more > demanding areas. I would tend to avoid the straight PVA white glues just to > be on the safe side. > > Please feel free to call if you have any additional questions. > > > > > Hugh W. Evans > Senior Applications Engineer > Industrial Adhesives and Sealants > Franklin International > > (800) 877-4583 > (614) 445-1555 (FAX) > > -----Original Message----- > From: Alan McCoy [mailto:amccoy at mail.ewu.edu] > Sent: Wednesday, June 27, 2007 1:04 PM > To: iasts > Subject: Aliphatic resin creep under load > > Hello, > > In our industry (piano rebuilding) there has been a lot of discussion > recently about the tendency of aliphatic resins to creep under load. Could > you please point me in the direction of any information that would shed > light on this issue? The traditional glue for many applications in pianos is > hot hide glue because it is strong, hard and will not creep. But many have > used aliphatic resin in recent years and I would like to know whether creep > will occur and under exactly what conditions. > > Thanks for your assistance. > > Alan McCoy > > > -- Alan McCoy, RPT > Piano Technician > > Eastern Washington University > 119 Music Bldg > Cheney, WA 99004 > > (509) 359-4627 > (509) 999-9512 > amccoy at mail.ewu.edu > > > > ######################################################################## > This e-mail message whether original or forwarded and any attachments to this > message are intended only for the person or entity to which it is addressed > and may contain trade secrets or confidential and/or privileged material. Any > unauthorized review, use, disclosure or distribution is prohibited. The > message should not be copied or forwarded to any unauthorized persons. If you > are not the intended recipient of this message, please contact the sender by > reply e-mail or by calling Franklin International at +1 614 445-1394 and > immediately and permanently delete this message and any attachments. If you > are an employee or agent responsible for delivering the message to the > intended recipient, you are hereby notified that you are prohibited from > printing, copying, storing, disseminating or distributing this message except > to deliver the message to the intended recipient. > ######################################################################## ------ End of Forwarded Message
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