Veneering advise

[zathras]

Hi all,

I'm hoping somebody can offer me some advise about veneering a set of speakers I built a few years ago.

The basic veneering is probably not too difficult, but the problem I have is that I originally covered the speakers with cloth backed vinyl using contact adhesive which is now peeling back and looks absolutely awful now.

The vinyl will probably pull off quite easily and will leave behind a tacky surface from the contact adhesive.

Can I simply use an iron on veneer straight over this ?
Failing that I can see quite a few sanding belts trying to get back to a clean MDF surface
Any tips on getting contact cement off of MDF ?

Cheers Ray

[Shane Watson]

I can't help you with the removal of the contact adhesive.

But one bit of advise I will offer

Stay away from iron on veneer at all costs!

Cheers!

[zathras]

How does one go about applying non iron on veneer?

PVA glue, contact ???

What is wrong with iron on veneer ?

Cheers Ray

[Shane Watson]

I've used PVA to apply veneer but the results vary. The problem with PVA is it's waterbased and once the veneer makes contact with it the veneer can sometimes chuck a tantrum splitting etc.
Best to use a non waterbased adhesive such as urea-formaldahyde or hide glue.

Iron on veneer dosn't last. The adhesive is terrible. All the iron on stuff I have used didn't last at all, so I refuse to use it now if a client requests it. You'll notice it especially if your summer temps can get high.

To do the job right will take a lot longer than you might think. Usually only one surface can be veneered at a time depending on your equiptment. Thats where the iron on crap sells itself as it sells itself as a one step no wait process.

Theres a lot of stuff on the net about veneering. If you do a quick search on google you'll find heaps of info. Will probably all be american though.



Cheers

[Harry]

Why not just start again?

[zathras]

Starting again is not an option.

These speakers stand over 1 metre tall and consumed two sheets of 25mm MDF so there is already a large investment in materials already.

Would an iron on veneer stick to the contact adhesive left behind is my basic question.

I suspect it would, and possibly may not have the problems Shane described as the contact has made quite a good bond to the MDF, it is only coming away from the cloth backing of the vinyl.

If I was starting from scratch, certainly conventional wisdom would be worth following.

Cheers Ray

[Marty Lott]

G'day Zathas, if you use lacquer thinners on the contact glue it should dissolve it. Try hitting it with a scouring pad dunked in the thinners. I'd steer clear of the iron on veneer,in my experiance it does'nt stay put permanently. If you happen to have some iron on veneer you want to use, remove the glue with thinners. Then you'll have plain old veneer. Try this....get some yellow glue(AV 180)coat one side of the veneer with the glue & the speaker. If the first coat is a bit on the thin side then put on a second. It's best to brush it on. Let the glue dry, then get an iron, set it to cotton & iron the veneer down. The heat will melt the glue on both surfaces & you'll get one mother of a permanent bond ! The beauty of this method is not having to clamp the veneer. It's great for curved surfaces also. I've tried veneering with hide glue...too bloody messy !

[zathras]

Originally posted by Marty Lott:
G'day Zathas, if you use lacquer thinners on the contact glue it should dissolve it. Try hitting it with a scouring pad dunked in the thinners. I'd steer clear of the iron on veneer,in my experiance it does'nt stay put permanently. If you happen to have some iron on veneer you want to use, remove the glue with thinners. Then you'll have plain old veneer. Try this....get some yellow glue(AV 180)coat one side of the veneer with the glue & the speaker. If the first coat is a bit on the thin side then put on a second. It's best to brush it on. Let the glue dry, then get an iron, set it to cotton & iron the veneer down. The heat will melt the glue on both surfaces & you'll get one mother of a permanent bond ! The beauty of this method is not having to clamp the veneer. It's great for curved surfaces also. I've tried veneering with hide glue...too bloody messy !

Thanks for that Marty, I'll give the thinners a try.
I vaguely recall elsewhere many years ago about coating both pieces with PVA typish glues and using an iron to bond them together, sounds the way to go for mine as these speakers are rather large and any other form of pressing would become quite expen$ive I'd suspect.

If only I'd known how cost effective veneers are, when you go to the right place, I wouldn't have had this problem in the first place

Cheers Ray

[ubeaut]

G'day Ray - Have you given any thought to an alternative like removing the glue and spraying with one of the decorative finishes that are around today. Like a wrinkle finish, crackle, splattered or something else. I have a feeling you are looking for trouble with the veneer.

The fancy finishes should be found at bigger hardware shops and the better paint shops. There are a lot of them available now, they are reasonably cheap, easy to apply and usually tough as nails. The paint should also cover and hide a multitude of sins beneeth.

Doing the veneering well, may not be as easy as you think, especially if as you say it is a very large. Don.t forget that putting the veneer on isn't the finish of the job. It still has to be polished and that's another kettle of fish, espesially over new veneer which often presents with problems that aren't encounterer on solid timber. Finally if it isn't done really well it could end up looking pretty bloody awful.

My gut feeling is this: If you veneer it is going to end up on the ordinary side of awful and you probably will wish you never started.

Hate to rain on your parade Ray, but......

Hope this helps or at least gives you something to think about. By the way the decorative finishes even poorely done will look better and probably last longer than the veneer.

By the way it is also possible that the paint may be able to be sprayed directly onto the glue. This you would have to try on a small section first first.

Cheers - Neil

[hamster]

Hi Ray,

For once, I find I am not in agreement with Shane(!). I use the iron on veneers extensively and find them extremely useful (and long lifed) for speakers, albeit with some caveats.

The newer generation veneeers seem to adhere better than the older ones but you still need to get the iron nice and hot and make sure every surface has been properly heated to ensure the glue is melted through. I also find that splitting only seems to happen when the veneer is old, especially common when you buy a sheet that has been hanging in Bunnings for 12 months. Fresh veneer is much less likely to split in my experience.

Also in my experience, when the veneer lifts some months after being applied it is not because the glue has "failed" but because it was not properly melted in the first place. This is the most common mistake people make with iron on veneers. You need to find a balance between initial temperature being high enough but not scorching the veneer, I find I need to iron over the sheets twice with a medium high iron before the glue is properly set. In other words, iron it on, let it cool and the re-set it again with the iron.

Two other warnings!

1) Remove the drivers (woofers and tweeters) and put them in another room whilst the thinners are open. Thinners and woofer voice coil glues are not friends! Make sure the cabinet is thouroughly aired afterwards.

2) Use the thinners very sparingly on the raw MDF. If you overapply them the MDF will swell and the veneer will never go on level.

*Disclaimer - I re-sell the CE iron veneers with my lou speaker kits so am horribly biased!*

Regards,

Marcus
www.theloudspeakerkit.com

[AlexS]

I won't buy into the discussion on types of veneers, but you might find eucalyptus oil more effective and safer than lacquer thinners for removing the remnants of the contact adhesive.

[zathras]

Marcus,

thanks for finally giving me some positive advise.

I'm in the process of building my entertainment unit at the moment and have already tried a couple of pieces of veneer on this, and yes I did scorch the surface of one piece. This didn't really worry me too much as I'm staining the timber black/ebony anyway.
The same deal will happen to the speakers (black).

If I didn't get the glue hot enough putting these veneers on, I'll be a monkeys uncle.

The veneers I've got are fresh stock from Lacey's Timberwood, they rang me when they came in stock

The butt join may prove to be a bit of a challenge, but I'd rather have a go and try as you never learn anything by not trying.

I will also try the eucalyptus oil as suggested by another poster.

Whatever happens, the vinyl HAS to go!

Cheers Ray

[BrianR]

I can't help with veneer but found a good way to remove contact cement. Had to clean up a Tas Oak floor that someone had cemented lino onto and tried stripper, hot air gun, sanding and scraping but no good.
In the end I used a hot air gun to soften the cement then covered it with talcum powder while it was soft and off it all came as easy as you like.

------------------
Brian

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[bfilmer]

I know it is a bit late.. probably too late anywhoooo.
I have built some speakers approx 1 metre tall and using MDF. I stained them using a Jarrah stain, about three coats in different directions and the effect is simillar to that of a very even dark grain. Very effective, I did a lot of trials first and then varnished over the top.
Also I built them 12 months apart due to cost restriction on parts and still managed to get them to match almost perfectly.
Where I let myself down was the varnish finnish which I am not fully happy with and will redo oneday.

[zathras]

Wow, that MDF must have soaked up the stain in the first few coats like a dry sponge

My speakers are MDF beneath the mess, but after being covered with contact cement may not be conducive to the same technique.

BTW, still yet to tackle the speakers, building the long needed entertainment centre at the moment. Using a slab of redgum as a feature piece and boy does it look GOOD.
Just got the bottom section in the house the other day and very pleased so far.

The speakers standing beside them (also about 1m tall) let it down with the damn vinyl peeling back

Cheers Ray