Hide glue interfering with dye absorption?

[DanDSilva]

Hello again,

I recently constructed a sheath for an antique-style hunting cleaver with a by-knife and fork in side pockets.  The main sheath, side pockets and facing are all thin, molded veg-tan, with a small amount of Titebond hide glue to hold the facing in place.  This is the first time I've built a sheath like this.  I just dyed it this afternoon and found that in certain areas the dye was patchy.

I suspect these are areas where the glue either soaked through or got onto the outside.  Is this likely to be the problem?  If so, is there anything I can do about it at this point?

Thanks very much for any advice.

Edited June 7 by DanDSilva

[DanDSilva]

Forgot to add:  I'm using undiluted Fiebings Pro Black brushed with a wool dauber.

[dikman]

Undiluted dye shouldn't matter, it's obvious that either there is some contaminant already in the leather or, as you surmise, the glue is bleeding through the leather and is preventing the dye from penetrating.

[DanDSilva]

Hm...  Is there anything I can do other than trying to make a whole new one without glue?

[chuck123wapati]

  On 6/12/2025 at 12:46 PM, DanDSilva said:

Hm...  Is there anything I can do other than trying to make a whole new one without glue?

Expand  

Maybe black acrylic paint would cover it otherwise, you might try contact cement on your next project, though. hide glue isn't usually used for leather work, at least to my knowledge, it's primarily used for wood.

[dikman]

I did a bit of research on hide glue and Chuck is right, it's primary use is for woodwork. It is water-soluble and not considered a permanent-bonding glue as joints that are glued with it can be opened up with heat and moisture, which would seem to make it unsuitable for leather projects as you don't want your work falling apart if it gets damp! The fact it is water-soluble could account for it migrating easily through the leather and interfering with dye absorption.

In short, it doesn't appear to be a good choice for leatherwork. 

[JLSleather]

NEver had glue "bleed through" leather.  🤔

But if it's on the surface, you can try to remove it by lightly dragging an art gum eraser to try to lift it off.  It will come off the grain side, just have to be careful not to mar the surface.
TO BE CLEAR, i'm not talking about RUBBING as in like youre "erasing" it... just trying to LIFT the glue from the leather, not embed it.

[DanDSilva]

  On 6/12/2025 at 11:31 PM, dikman said:

I did a bit of research on hide glue and Chuck is right, it's primary use is for woodwork. It is water-soluble and not considered a permanent-bonding glue as joints that are glued with it can be opened up with heat and moisture, which would seem to make it unsuitable for leather projects as you don't want your work falling apart if it gets damp! The fact it is water-soluble could account for it migrating easily through the leather and interfering with dye absorption.

In short, it doesn't appear to be a good choice for leatherwork. 

Expand  

Interesting.  The reason I tried it with hide glue was on the advice of several people who say they've used it for similar projects -- one suggest it for a two-layer leather scabbard and another for adhering the facing to a wood core with side leather pockets.  I've used it before myself, but not in cases where I'd then dye it -- one was a rawhide facing on a wooden shield which I then sealed with oil paint, and another was a pre-dyed chrome-tan facing on a wood scabbard core, which I applied dry.

After thinking it over I'm beginning to lean toward the glue getting out through the openings in the facing for the side pockets and getting smudged as I stitched the facing.  The fact that I applied the facing wet probably didn't help.

I'll look for a gum eraser, but if I can't get one I'll just dye and dye again.

Edited June 13 by DanDSilva

[TomE]

Need to determine if the uneven absorption is intrinsic to the leather versus a result of glue bleeding through to the grain.  I woud check whether a scrap of the same leather takes up water or neatsfoot oil evenly, then explore other causes from there.  Uneven density of the fibers in the leather can affect how it absorbs dye and other liquids.  Some parts of the hide are less uniform in structure and tanning faults (= cheap leather) can also contribute.  A possible remedy is casing the leather or lightly oiling before dyeing to open up the spaces between the fibers . 

Contaminants that interfere with dye uptake can be cleaned off the surface with a solution of oxalic acid.  A few teaspoons in a quart of warm water.  Oxalic acid is a mild bleaching agent used by saddlers to prep leather for dyeing.

[MarlinDave]

I've had leather (Mostly Tandy) have spots that would not dye, even dip dying a time or 2.  I am thinking tanning process was not complete. If you are like me, I usually make one project, ruin it somehow, and make a second one.  The originals are in a box I call the Island of Misfit Holsters.