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Günter VögelBerg
02-13-2019, 11:42 AM
I have previously only used paper-backed veneer with contact adhesive. For this project I am using raw veneer (walnut, fairly flat) and MDF substrate. I don't have vacuum equipment. On the bottom of each panel I have a 10-inch concave radius in the 3/4 MDF and I need to adhere a narrow strip of the walnut to cover it. The grain orientation of the walnut is not important.

My initial plan was to use a cold-press veneer glue and make some hemispherical clamping cauls sized to fit into the arch minus a small amount to accommodate the thickness of the veneer. This seems potentially problematic for two reasons: sizing the caul precisely and clamping it to the panel. I also need to do 8 of these panels and would have to do them in batches since I don't have enough clamps or space.

My other idea is to use heat-activated glue (which I am using for the rest of the project) and use a hair curling iron from the local charity shop to heat it. Does it seem reasonable that I would get enough surface area contact to get a good bond?

Is there another approach more practical?

Thank you for your input. I am enjoying your website.

Peter Christensen
02-13-2019, 12:35 PM
I haven't done it but how about a sand bag. Heat it to set the glue.

A metal shoe attached to the bottom of a clothes iron would give more contact if you prefer to go that route.

Mike King
02-13-2019, 12:37 PM
Hammer veneer with hide glue?

John TenEyck
02-13-2019, 7:11 PM
For a 3/4" thick substrate iron on veneer works great. I've done all kinds of concave and convex curves with it. I use a household iron and you can get down into a 1/2" radius by using the edge of the iron. With MDF I think you might want to wipe a coat of wood glue on the edge first so the veneer tape has a more solid surface to stick to.

John

Günter VögelBerg
02-13-2019, 7:23 PM
For a 3/4" thick substrate iron on veneer works great. I've done all kinds of concave and convex curves with it. I use a household iron and you can get down into a 1/2" radius by using the edge of the iron. With MDF I think you might want to wipe a coat of wood glue on the edge first so the veneer tape has a more solid surface to stick to.

John

So are you saying hold the iron so its sole is perpendicular to the veneer surface?


I have always put off using hide glue because I did not want to mess with a glue pot, but after doing some reading today it is time for me to try it. However, I'd really like to get this project going without having to wait for yet another item to come in the mail.

John TenEyck
02-13-2019, 8:37 PM
So are you saying hold the iron so its sole is perpendicular to the veneer surface?

.


Yes, turn the iron however you need to to press the veneer tape to the surface. Once you have it heated use a wood block to press it down, smooth it, and help it cool. With Melamine iron on tape I've made some really tight inside corners using a dowel to press it into the corner. With wood iron on tape I think about 1-1/2 - 2" is the tightest inside radius I've done. I don't know how tight you need to go, but at some point the wood will break unless maybe you soak and pre-bend it.

John

johnny means
02-13-2019, 8:57 PM
I press my veneer onto a flexible substrate like 1/8" mdf. I then use spray adhesive or glue and clamp that to my piece. The flexible substrate is much easier to attach while allowing my veneer to lay nice and flat/smooth.

Günter VögelBerg
02-13-2019, 11:37 PM
Yes, turn the iron however you need to to press the veneer tape to the surface. Once you have it heated use a wood block to press it down, smooth it, and help it cool. With Melamine iron on tape I've made some really tight inside corners using a dowel to press it into the corner. With wood iron on tape I think about 1-1/2 - 2" is the tightest inside radius I've done. I don't know how tight you need to go, but at some point the wood will break unless maybe you soak and pre-bend it.

John

It is a 10 inch radius, so not tight enough to break the veneer. This will be "raw" veneer and heat-activated glue, which I presume would be a similar procedure as the tape. I have some "veneer softener" I am planning on using.

Phil Mueller
02-13-2019, 11:58 PM
You may want to look into Titebond liquid hide glue...available at most woodworking, hardware, big box stores. Same general properties as hot hide glue, just no need to heat it.

Jim Foster
02-14-2019, 7:57 AM
I have not tried it yet, but would not hesitate to try veneer hammer and hide glue as suggested above.

Edwin Santos
02-14-2019, 8:57 AM
I don't have any advice to add, but it sounds like an interesting project and I hope you will post some progress or completed photos here.
Edwin

John TenEyck
02-14-2019, 3:09 PM
It is a 10 inch radius, so not tight enough to break the veneer. This will be "raw" veneer and heat-activated glue, which I presume would be a similar procedure as the tape. I have some "veneer softener" I am planning on using.

A 10" radius is like no radius with pre-glued wood veneer tape. Have at it!

John

Tony Leonard
02-14-2019, 3:17 PM
Well, I did the opposite - edge of a circular table. I used a piece of formica lined with cork as a caul. Used a band clamp to apply force. I made the caul for the bad clamp and lined it with cork as well. I used lots of blue tape to clamp the veneer first. Anyway, this worked quite well. Good luck and let us know what works for you.

Tony

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Günter VögelBerg
02-23-2019, 7:42 PM
After trial and error I had the best results using a heat gun to heat the substrate then to heat the veneer as I rolled it with a hard rubber roller.
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