Which Adhesive Is Best

[splitrail]

I am sure this has been discussed in detail before, but I am having issues with the contact cement I am using and would like some help from the pro's.

I was using Barge's Tanners Bond from Tandy. Lately I've noticed it has turned very thick and stretchy, so I assumed the shelf life on it has expired. Too much open air maybe.... it has sticking power but won't seem to hold the two layers of leather together, they are seperating after burnishing.

So I purchased DAP's Weldwood contact cement. But I am finding that after letting is set up properly, glueing and clamping... the next day I can pull the layers apart, I have not tried to burnish yet, that trial is setting up as I type.

Any success stories would be appreciated. Thank you for your time.

[DS STRAPS]

Are you letting the 2 pieces dry before contacting, I noticed the same issue when I would contact the pieces before dry to touch and also was thick and stringy. you can try to use the barge thinner to thin the cement you currently have. That is good to know about the DAP, I was actually considering trying that brand.

[TomG]

I've used Weldwood for some time now. If you apply it properly, it will "pull apart", but that is actually the fibers of the leather ripping out, in my experience.

If it's much thicker than Karo syrup, something is wrong. Old... been frozen.. something.

As for thinning. a couple of long-time woodworkers told me to thin contact cement with the same brand of thinner as the cement. Something about the solvents used between different brands.

I've heard others thinning with Acetone, but never tried it.

[splitrail]

Thank you both for responding. You might be right about the "freezing" on the Barge's I did have it in storage in Canada for a while. I think that can is a goner.

I just performed a burnishing test with the Weldwood and it burnished fine, and has nice flexibility. But it does peel apart with very little effort. I let it set up for a good 20-30 minutes, seemed dry to the touch. I then clamped it for a couple hours, then beveled and burnished, Looks good. Still concerned about it seperating. Wondering if the high humidity and heat here right now is warrenting a longer dry time?

Thanks again for your thinning tip. I do love the consistency of the Weldwood, easy to work with!

[electrathon]

I know it is not real popular but I love Renia in the green can. It is very smooth applying and has incredible hold strength. I have tried many other glues and find it to be the strongest.

[TomG]

Maybe I'm doing it wrong. But I don't let it dry totally. I wait until its a little tacky (about 10 minutes or so), and then press together and clamp overnight.

That being said, if I have really porous or "fluffy" leather, I have been known to apply the cement as a sealer, let it dry for an hour or so, and then apply a second coat and then join when tacky.

[splitrail]

Renia, is that easy to come by?

and

Tom, I hear you on the 2 coats... the first coat seemed to disappear into the leather I am using now.

[electrathon]

Renia, is that easy to come by?

I get it at Oregon Leather. Not sure about other states. It is the glue many cobblers use to glue the soles on the bottom of shoes with, so it has to stick well.

[Busterradar]

I use Weldwood but I leave it for 1-2 hours before I put my 2 pieces of leather together. I don't have any problems with my edges at all. Also a little trick I use is I put the can in hot water for awhile, shake it up then open the can and pour it into clear plastic bottle like you would use for mustard. I find I make less of a mess and can put the glue right where I want it.

[splitrail]

Thank you all for the great advice, patience is what I need.

And I love the tip on warming it up and using an applicator.

[byggyns]

I use the weldwood. I find that if you rough the leather up a little before using it: a light sanding to remove any surface glaze, that it works better. I also only let it get tacky, not dry completely. Once I put the surfaces together, I tap the joint with a mallet. I find that without the tapping, it does not stick as well.

[Halitech]

I'm using Tandy's Eco-Weld. It comes out like white glue and seems to really bond well. I've even used it to glue edges together in a butt joint and it held while sewing them together. I usually let it sit about 20 minutes or so ( I usually forget about it while I do something else)

[Dwight]

The rules for Weldwood are simple:

Put in on thinly, . . . let it dry to the point that there are no sticky places at all on what you are doing.

Rough up any hair side parts, . . . and don't be gentle. It will not be seen once the glue it put on and glued together, . . . rough it up good.

I have never found any reason to clamp anything I've done with it, . . . been using it for over 50 years. Press the two pieces together using the flat palms of your hands, . . . and whatever upper body weight you can bear down on it, . . . then leave it for several hours.

And YES, . . . acetone will thin down Weldwood, . . . I had an order for 3 belts not long ago, . . . and my can was near the bottom, . . . kinda thickened. I added a couple ounces of Acetone, . . . stirred for 5 minutes, . . . back in business. All three belts were put together with no problem at all.

Another YES, . . . you can pull two pieces of leather apart that have been properly bonded with Weldwood, . . . but if you take a good look at what really happened, . . . you will find that the glue did not give way, . . . the leather fibers separated, . . . allowing the two pieces to separate. The only exception to this rule is when you use it on the hair side and don't properly scuff up the hair side surface.

May God bless,

Dwight

Edited June 6, 2015 by Dwight

[ThaKaptin]

Is the Weldwood good for joining 2 pieces of leather that will be flexing a good bit and is ONLY going to be held together with the glue? This is my first piece and I'd like my first piece to be something that even though it may not be the best looking piece, will be around a while. I'm sentimental like that. lol

Wanted to add that the post above mine was SUPER informative and I appreciate the detail very much. Details are awesome when you are learning.

Edited June 6, 2015 by ThaKaptin

[Halitech]

relying on glue on is not usually the best idea. I think most of us use glue only to help things together until we finish assembly with sewing or rivets

[YinTx]

splitrail,

I had a similar experience lately here in South Texas with the Barge contact cement. It has been working great, and then recently in the heat and humidity, it seemed to falter. I was able to separate the two pieces, where I would not have been able to recently. I thought maybe it had to do with the age of the can, so I opened a new can, it had the same problem. In fact, when I was sanding the edges, I was able to pull the cement out from between the layers after they had been hammered together, like a rubber band. I reapplied a different glue to bond the pieces together before finishing. It was clear that the cement had not bonded to the leather fibers at all, since it came out with no fibers attached. This was after letting the cement set for about 30 minutes to be slightly tacky to dry to the touch prior to putting the pieces together. I am really inclined to believe with this experience that heat and humidity had something to do with it, but I don't see the chemistry that supports my experience.

YinTx

[splitrail]

YinTx

Being a Canadian, I am personally trying to get used to thisTexas heat and humidity... on top of the adhesive issues. haahha

I have been working with the Dap for a couple of days now and it's applying very nicely. Much smoother, not Rubber Bandish at all. I am currently stitching a project that was glued and then the final test will be the burnish.

My tiger thread arrived yesterday, it's sweet to work with.

Maybe storing the can in A/C will help?

And thanks for taking the time to respond and for the photos you post, I love looking at everyone's work.

[wlg190861]

Halitech is right. glue is meant to hold until you finish by sewing or some type of lacing. Burnishing leather that has just been glued will heat up the glue an make it soft. As far as the strongest glue, it is made( by Mule hide ) and sold at your local ABC roofing supply store, it is called black splice adhesive. once you put the two pieces of leather together they will not come apart

[splinters]

How about using rubber cement that has been thinned to a brush able consistency, applying to both pieces and letting dry before pressing together?

Edited June 8, 2015 by splinters

[ThaKaptin]

Thanks for replying. The only problem is that there isnt really gonna be a place on the piece where there is gonna be room for stitching or rivets. I can extend it a little bit and MAKE room but its not going to look NEARLY as good. I thought about doing that and using some kind of decorative chicago screw but if I can get away with not doing it it will look a lot more true to the time and place that its supposed to be emulating.

[electrathon]

How about using rubber cement that has been thinned to a brush able consistency, applying to both pieces and letting dry before pressing together?

In general, rubber cement is for temporary bonding, contact cement is for permanent bonding.

Properly glued, contact cement is permanent. Good top quality contact cement is strong enough to glue and hold the sole on a shoe, you can't get much more permanent and in need of strength than that.

[splinters]

In general, rubber cement is for temporary bonding, contact cement is for permanent bonding.Properly glued, contact cement is permanent. Good top quality contact cement is strong enough to glue and hold the sole on a shoe, you can't get much more permanent and in need of strength than that.

If I understand correctly then the rubber cement would be OK to temporarily hold two pieces together that I was going to stitch together.

Thanks for taking the time to set me straight.

[Thor]

Renia is a German brand which is used a lot by shoemakers. For some funny reason it is not as popular here like kövulfix which comes from up north.

Anyway wood glues do work for me well. I'm using Ponal. Like most wood glues they aren't meant for bending and will stiffen the item a bit. Environment is a killer for most any wood glue. Read the manufacturer's directions. For instance, Ponal will loose some of it's bonding properties at low temperatures and all if frozen or too old. As for thinners you should see what the base is, some have to be thinned with water and others with the brand's own thinner. I never keep wood glue longer than a year. Also wood glue should not be set to dry or get tacky before putting the pieces together. If you do, the pieces will come apart.

Renia offers a range of glues and they have been to Sheridan this year as well as coming to San Antonio this October http://www.renia.com/englisch/start.html so their products should be available in Texas as well. Here's an overview on a UK page of their products http://www.algeos.com/html/products/adhesives/renia.html

[electrathon]

If I understand correctly then the rubber cement would be OK to temporarily hold two pieces together that I was going to stitch together.

Thanks for taking the time to set me straight.

Yes, if you are going to sew you can get away with just rubber cement. You may have some separation along the lamination line over time.

On items like wallet insides I will often use leather weld. It allows repositioning and does not gum up the sewing needles like rubber or contact. If I need it to really hold I use contact.

[rawcustom]

Good thread, like you I figured this info is buried in the archives and I've been hesitant to start digging. I have experimented with many adhesives in many different applications.

IMO the absolute strongest bond you will get in leather is a polyurethane glue like gorilla glue. However polyurethane glues are terrible messy with all the foam and expansion and require a lot of clamping pressure to work right (force the foam expansion into the material, not force the joint apart). Most times you will be left with noticeable clamping marks, and it will make items much more rigid.

Epoxy works great when the leather is clean and dry, but takes time to cure, can be a mess, can soak in and discolor, needs less clamping than poly, and is not very flexible.

Cyanoacetate (superglue) great for tacking clean leathers, soaks in and discolors easily. Hard to work with because it runs everywhere if you use it in volume and dries very hard. I would not want to sew through it.

Contact cement, I have used Barges blue (without toluene) Petronio master, Wood DAP, and E6000.

Barges blue seems to be very messy with stringy'ness in the application. Bond seemed adequate.

Petronio Master has been my favorite, but thickens by the bottom of the can. I'll have to try to thin with acetone like suggested above.

Wood Dap has been adequate and the easiest to find for me. It seems to be the thinnest of the CC I have used, but seems to work fine.

E6000 I don't like this one very much. It dries way too fast and I can't seem to find the happy medium of tacky for a good bond but not too set that the glue is dried.

When I apply CC and the glue seems to absorb in I rarely add more. I don't think adding extra gunk to sit between the layers is going to do much. I've also found that letting them sit to long is when I can pull the cured glue out from the seams. After pressing the pieces together I always hammer on the joints as I read that somewhere and why not beat on things when you have the chance?