I believe the makers use that rubber glue that the leather makers use, but wouldn't swear to it..I would think one of the spray glues would work best, and if sprayed lightly would not leak through..
I know this thread is old, but in case anyone was looking this up
Ray is correct regarding the use of "leather glue", however it is not "rubber". The rubber glue is a
low contact glue used to temporarily affix pieces, padding, etc... before stitching. (allows you to adjust it easily) The preferred glue would be "leather contact cement" which is water based, therefore it has no caustic solvents that will release and attack metal/wood surfaces. Additionally once it dries it is non-permeable, so it is resistant to moisture. Below is a link to a popular brand used-
Can w/ Brush- (Tanners Bond Craftsman Contact Cement)
Tandy Leather Factory - Tanners Bond Craftsman Contact Cement
Spray can- (Tanners Bond Craftsman Contact Adhesive Spray 12 oz.)
Tandy Leather Factory - Tanners Bond Craftsman Contact Adhesive Spray 12 oz.
I post this because of the knowledge I gained from my Dad. My father is a master carpenter and for many years built pistol boxes, gun boxes, shadow boxes, cabinets, etc. At one time he had a contract building custom boxes for black powder/percussion dueling pistols, they were presented as service awards.
You can also find an "archival" mounting adhesive at most hobby shops, be sure it is for "archival" use. Some adhesives found in fabric stores are okay, but may have harsh solvents or are not resistant to moisture.,
The reason for using a leather glue is that wood is similar to leather in that it is affected by moisture or humidity. That is why adhesives fail or de-laminate.
Hope this helps
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