Regluing old repairs

[realtorone]

This may not be the proper place for this but.I have a John Ford flint rifle with two glue repairs which came loose and I've tried to glue them back with little success.
These repairs are just under the Frizzen and just under the Hammer.Both cracked along the grain line and the original wood was replaced.When I attempted to clean the old glue and re glue the pieces one held and one didn't.Any ideas
Thanks in advance. 
   George

[Blacksmoke]

George:  Yes this is the right place.   I am involved quite heavily with restoration on old guns - mainly muzzle loaders.   I am assuming that you did not do the first repair to the stock on the gun that you mentioned in your post.  Is it the same kind of wood as the original?  Is it new wood that was added to old wood?  Some times I have to remove the old repair and start over again because the well meaning repair person did not have the necessary expertise to do the job properly.  Can you post a photo of the needed repair.   It is quite difficult to answer your question from  this distance with out seeing it, even with a photo.        Hugh Toenjes

[realtorone]

Hugh
The original repairs as well as now are the original wood.Where you have to place the glue is rough because the cracks are along grain lines.Because it's the original pieces which cracked and came out I want to use them to repair.
As for photo's I have not mastered posting Photos,So far other members have posted photo's after I E mailed them as attachments.

Thanks George

[Blacksmoke]

George:  Please feel free to e-mail me and attach pictures - then I might be able to help you more:   hjt65@hotmail.com   Hugh Toenjes

[Bob Smalser]

When dealing with the possibility of old glue residue remaining in cracks, it will be useful to understand which glues are compatible with each other and which are not.  You can generally tell from the glue line what glue the previous repairs were made with.

http://www.wkfinetools.com/contrib/bSmalser/art/glueTest/glueTest1.asp

http://www.sawmillcreek.org/showthread.php?21822-Are-Your-Glue-Joints-Repairable

Resorcinol: The marine standard. If you can get 70 degrees F or higher for an overnight cure and consistent and high clamping pressure with no gaps, you won’t go wrong using it. Cover it overnight with an electric blanket to make sure. Likes wood at 10-15% EMC, according to Navy tests. Long open time. Repairable with epoxy. Ugly red glue line.

Marine Epoxy: The repair and restoration standard. Bonds well to a wide variety of materials, and usable in almost all flexibility and temperature conditions. Needs no clamping pressure, only contact…fills gaps well. Likes wood below 12% EMC. Repairable with itself, joints can often be broken apart for repair with using heat. Clear glue line and can be dyed to match the wood. Controllable open time with different hardeners. Slightly permeable to water vapor and there are reports of failures in fully saturated wood and with White Oak. Very sensitive to UV, requiring protection, and doesn't like heat. If you are scarfing planks that will require steambending, use resorcinol instead.

3M 5200: A rubbery, polyurethane sealant in various colors with adhesive properties sometimes used as a glue. Fails as a glue under water saturation without high clamping pressure, and without the proper strength testing I couldn’t do here, it’s not recommended as a stand-alone marine glue. Repairable with epoxy.

Liquid Polyurethane: Gorilla Glue, Elmer’s Probond, Elmer’s Ultimate, and others. Versatile in temperature and bonding wet wood with moderate open time, these glues aren’t rated for below waterline use but initial use shows potential as a marine glue. Likes high clamping pressure and fits similar to resorcinol…it won’t fill gaps. Will successfully glue green wood at 30% EMC. Repairable with epoxy. Doesn't mind heat...poly can be used to glue steamed laminations without cooling them first. Noticeable, yellow-brown glue lines.

PL Premium Construction Adhesive: This polyurethane goo shows promise as a marine glue with further testing and use. Works like 3M 5200 but cures and behaves like liquid poly. Appears to bond well to everything epoxy does, and more where epoxy and liquid poly won’t, perhaps because of a higher isocyanate content…it bonds to difficult surfaces only cyanoacrylate super glues will bond to. The only general-use glue I’ve found that will bond difficult aliphatic-contaminated surfaces. Appears flexible to temperature and moisture content with gap-filling ability, but as a construction adhesive, its open time is shorter than liquid poly. Appeared to like high clamping pressure, and unlike other glues, wouldn’t bond at all without at least some. Repairable with itself and epoxy. Glue line as in liquid poly.

Urea Formaldehyde Plastic Resin Glue: The old interior furniture standard, and in older marine applications that required well-blended glue lines. Still preferred by many, as it is a no-creep glue easily repaired using epoxy. Long open time, it needs tight fits and 65 degrees F or higher for an overnight cure…it doesn’t fill gaps. Best glue line among them all and moderate water resistance still make it useful for protected marine brightwork applications. A relatively brittle glue and UV sensitive, it requires protection….but its brittleness is an aid to reparability, as joints can be broken apart for repair. An inexpensive powder with a short, one-year shelf life.

The Titebond Family of Aliphatics: Convenient. No mixing, just squeeze. Short open times, fast tack, and short clamping times. Flexible in temperature and to a lesser extent in moisture content, but the bottled glue can freeze in unheated shops. A flexible glue, it has been reported to creep under load, sometimes several years after the joint was made. The latest “Titebond III” appears to be a stronger glue than its two predecessors. Difficult glues to repair, as they won’t stick to themselves and no other glues will except cyanoacrylates, which are too brittle for general use. Epoxy and fabric aren’t bonding to aliphatic glue lines in marine strip construction, compounding repair difficulties. While not definitive, the new PL Premium appears to bond well to Titebond III residue and is worth pursuing by those repairing old white and yellow aliphatic joints.

[realtorone]

Hugh I'll send E Mail photo's this weekend
Thanks a lot
George