Veneer questions

[Anonymous]

Hello everyone,
This is my first post. It's a great woodworking information resource you have here!

I'm building a pair of large loudspeakers and plan to veneer them with 0.6mm quilted maple using the PVA and iron method. The carcass is solidly constructed from two18mm sheets MDF laminated together and glued + screwed so it won't be coming apart anytime soon. As I said, these are quite large: approx 1m high x 400mm deep x 260mm wide. The look is blatantly ripped off from these:
http://www.avalonacoustics.com/opus-grand.html

I've used paper-backed veneer before but this is the first time I've tried using the raw stuff. I've attached a picture of the veneer - will this be flat enough to work with? I applied some PVA to a couple of scraps and the veneer curls-up within a couple of minutes...

Any other tips or advice is very, very welcome!

Regards,
David.

 

[simuk]

Hi dave,

Welcome to the forum mate. Cannot help you with the veneer, but will be interested to hear how you get on as i have been thinking about making some speaker cabinets myself.

Are you replacing cabinets or are these for new speakers?


Simuk

 

[Chris Knight]

David,
It is plenty flat enough. You just need to spray the non-glue side with water as quickly as you can after spreading glue on the glue side - you can also wet the non-glue side first, do whichever works best,. This causes the veneer to try and curl the other way, thus counterbalancing the tendency for the glue to curl it.

 

[JFC]

Hi Dave , i have done a small amount of work with maple veneer but not enough to be an expert on the matter . From what i remember its important to keep the veneer flat at all times before use and i notice from your pic it seeks to be curling . Do you normally store it with a board over the top to keep it dead flat ?

 

[Anonymous]

Thanks for the replies guys.

Simuk: Thanks for the welcome. This is a new design - I've built several speakers before with great success, but this is by far my most adventurous attempt! I'm an electronic engineer by trade so have access to all the electrical and acoustic test equipment needed to fine-tune the design.

Chris: Thanks for the input. I was hoping you would reply as you seem to be the veneering expert round these parts. When you say wet the non-glue side, do you recommend pure water or the water + glycerine mix I've read about?

JFC: The veneer was only delivered a few days ago and I've kept it in the box it arrived in. I've been storing it in the house (as opposed to the workshop or gargae) to try to keep the humidity constant.


Any recommendations for glue? I'd like to avoid contact cement so that I can have the oppertunity to adjust the position of the veneer. Is the PVA and iron method the best for this kind of project?

Has anyone tried the iron-on glue film such as...
http://www.marquetry.co.uk/main/acatalog/Tools.html

Cheers,
David.

 

[Chris Knight]

David,

Plain water will be fine - I use a plant mister for that job.

For glue and the iron-on method, I use regular woodworking PVA thinned 50%. I apply two coats to both substrate and veneer. You will find that this gives the veneer a nice strong quality and it can be handled with much less risk of damage. You can wait days or even weeks before you need to apply the veneer if you use white PVA. If using yellow Titebond, I try to get it on within a week as leaving it for too long makes it harder to melt once you start ironing. With MDF it is good to lightly sand the substrate with 80 grit sandpaper before applying the PVA.

The iron on method is excellent for this sort of project. You could also use contact adhesive although I don't like that myself, it is useful if you have concave curves to fit as you can't get an iron into them.

Since you have apparently built the boxes already by the sound of it, your options have been somewhat limited. Had you veneered the MDF before building them you could have used a vacuum bag or a press to veneer the sheet material

The best description of the iron on method is in this book. Veneering: A Foundation Course by Mike Burton http://tinyurl.com/d2yug I can olny see it at present on the USA Amazon site although I got my copy here in the UK

 

[Alf]

Welcome to the forum, David.

Has anyone tried the iron-on glue film such as...
http://www.marquetry.co.uk/main/acatalog/Tools.html

Yep. Personally I had mixed results. First time I was impressed, so I ordered some more. I was much less impressed - and in fact threw it away. It does seem to degrade very quickly, so perhaps I had an old batch (not from there, btw). Probably best avoided on the whole.

Cheers, Alf

 

[Steve Maskery]

Hi David
Maybe it's just me being incompetent, but I've found that the iron-on method is good for only the most compliant of veneers, and curly maple, in my experiece, most certainly doesn't fall into that catogory. Given the value of the curly maple v the cost of a sheet of MDF, I'd be tempted to make the speakers again, but veneer them in a press before assembly.

Alternatively you could still veneer them in a bag by cutting a platten a tad oversize and veneering the speakers onto the veneer, rather than the other way round.

Whatever you decide, good luck.
Cheers
Steve

 

[senna4ever]

Hi I always use animal glue for veneering. The first few times it seemed quite intimidating and I used to circle the job for a day or two before getting the courage to go for it. The great thing about animal glue is that it is reversible if things go wrong.

If you follow this link you should find some good advice

http://www.finefurnituremaker.com/publi ... ntents.htm

 

[AndyBoyd]

I too tried the glue film you can buy and found it very hard to veneer large pieces (say 80cm x 30cm)

I now use just normal slow pva glue and a large thick panel (10cm thick) as a press, made up of laminated 22mm MDF. Plus loads of clamps.
Spraying the front of the veneer with water is also a good tip, I've even been told to adde some glycerine to the water if the veneer is very warped and curvey.

 

[Waka]

Dave

can't help you with the veneering, Chris is the expert, but welcome to the forum.

 

[Jake]

I used contact adhesive for my speakers. A thixotropic one allows you to get the stuff in the right place before rolling it down, and even to adjust slightly after you have rolled down the edge where, for example, it abuts the previous sheet. My veneer was curlier than yours, I wetted it and pressed it under some continboard for a week or so. That got a bit but not much of the warp out, and rest went as it was glued down. It's worked fine generally, but at certain times of year the veneer "bubbles" a bit in a couple of places where it is curved around the radius between the top and front - it's not quite fully bonded to the mdf, I suspect either not enough glue or just the wrong type. As you don't have any radii to deal with on an avalon clone, it should be fine. It has the advantage of being very easy to deal with.