# Gluing hardboard to hardboard?



## jdonhowe (Jul 25, 2014)

I've been finding honest-to-goodness 1/4" thick hardboard hard to come by, at least at big box stores. OTOH, I have a lot of 1/8" leftovers, both smooth on both sides and one smooth/one rough side.

Before I dive in, are there any pitfalls with gluing two (or even more) layers of hardboard together to make thicker pieces, such as for templates or more rigid panels? It's my understanding that tempered hardboard has a linseed oil coating, which might interfere with good bonding. Also, would gluing a rough (unfinished) surface result in swelling and possible rippling? Titebond II is my usual go-to glue, but would any other glue be better?

Thanks in advance for any thoughts :smile:


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## Steve Neul (Sep 2, 2011)

How big are the parts you are needing? If they are very big I would use something else that was already 1/4". If the parts are small and the masonite has a textured back I would use gorilla glue to laminate them together. I would rough cut them about 1" wider and longer before laminating. They could also be laminated together with contact cement. With wood glue it tends to glue nice around the edges and won't dry in the middle for a very long time. Resin glue would also be good for that application but is a bit expensive.


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## bauerbach (Mar 25, 2012)

I would sooner spend for 1/2" or even 3/4" than to deal with this hassle... best part of manmade wood is its uniform thickness, soon as you try to laminate it, I think you will get voids that make the result a pain to work with. For all the time and glue you use, might not even save anything.


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## jdonhowe (Jul 25, 2014)

I don't have any specific immediate use, but was thinking of relatively small router templates- mostly looking for a way to make use of scraps. Thanks for the glue suggestions, Steve- I do have some resin glue- I'm thinking Gorilla glue might swell too much. And thanks, baurerbach, for the reality check- I'm probably being penny wise-pound foolish. Good idea to just move up to 1/2".


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## Steve Neul (Sep 2, 2011)

Gorilla glue is kind of expensive for that application but it should work alright. Weight it down good so the glue swelling won't affect the thickness.


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## BernieL (Oct 28, 2011)

The problem with gluing hardboard to hardboard is the same as gluing finished boards to finished boards. Regular wood glues will not penetrate the finished surfaces... but one type of adhesive will. I've tried multiple impossible glue-ups and have found "Loc-Tite" PL adhesives to work just fine. Here is a link to Home Depot's sale http://www.homedepot.com/p/Loctite-PL-Premium-10-fl-oz-Polyurethane-Construction-Adhesive-1390595/202020473 

Another popular brand name is "Liquid Nails" Construction adhesives come in tubes and you will need a caulking gun (under$4). The tube does create a problem in that too often, it will dry-up before you need it again. I haven't been able to overcome this challenge, but I've been able to increase the shelf life of a tube by inserting a long screw into the tube when I'm done. Screws have threads that will grab the drying agent out of the tube.


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