Vacuum Veneering Kitchen doors

[mbartlett99]

I've finally returned home and about to start constructing 20 doors for my never ending kitchen project. The doors will have a 75mm mitred cherry frame and a panel veneered with ripple maple.

Having unsuccessfully tried ironing on the veneer (50% success rate - bubbles in the middle) I found that Bagpress were just down the road and so got a kit from them (very helpful). But I've never used this gear before and wondered what glue might be best and where to get it? Any other tips on this would be great.

Also, I'm tempted to glue the panel in to lend strength; mitres will be dominoed but I'm not convinced they'll take the knocks over the year without opening up. Movement on a 75mm frame shouldn't be an issue should it?

 

[doctor Bob]

Any particular reason for mitres rather than traditional door construction?

 

[mbartlett99]

Yeah thats a very good point. I'm a bad one for getting an idea and holding onto it common sense or not Bob.

Decided that I don't want a simple flat frame, although it would be much much easier. It'll be moulded - I've a spindle moulder and the tooling - and that knocks out a simple construction.

This entire idea may be due to my experience with picture framing (got a morso) and nothing else. Just don't want it to be boring I guess.

 

[custard]

By and large I prefer PVA for vac bag veneering. The main reason is I want the job done in a reasonable time and as I can only run two vac bags maximum that often becomes a bit of a bottleneck so I don't want to hang around waiting for a UF glue to cure.

Some people thin their regular PVA with about 10% water, but I'm not keen on that as the added water can bring other problems, I either use a special veneering PVA from Titebond, or I get the (cheaper but just as good) veneering PVA from Airpress. I roller the PVA on and work fast! For really large flat sheets you can save yourself some stress by veneering just the underside of the job, then after about 30 minutes whip it out of the bag, trim the overhang, and veneer the other side. By placing the veneer on the underside (sandwiched between the bag platten and the workpiece ground) you can have quite a large overhang of veneer without it breaking off. It's slower, but if you've never done vac bag work before it's less stressful and you don't need precisely cut cover boards.

Mitred doors sounds like a potentially very, very bad idea by the way!

 

[mbartlett99]

Cheers Custard

I've got a bottle of titebond cold press and will probably use that as a test piece. Not too bothered by the time - got enough other things going on to keep me busy and space o do it. Was going to use Cascamite/one shot.

I am concerned about the mitred doors. Not so much the making of neat mitres or even joining them but just how well they'll stand up over time - hence maybe gluing the panels in.

 

[Droogs]

dodgy gluing in the panels a lot of temp and humidity changes in a kitchen. Would suggest splines in the mitres if that join is a must for the project. Even just a saw kerf thick with a slice of veneer would do

 

[mbartlett99]

I hear ya Droogs and am still considering that option. Onne thing that is a bit interesting on that though is my neighbours fairly high end kitchen the panells all seem to be glued.

Oh dear indecision is creeping in again.

 

[woodbloke66]

If you want to speed up the time in the bag using PVA (I used Everbuild D4) put an electric blanket over the bag followed by an old duvet to keep everything super toasty - Rob

 

[doctor Bob]

I use resin, these days the hardeners can be altered to quick medium or slow. Much easier to control the speed of set.
Big complicated job, slow set. quick simple panel quick set.
Much better bond in my opinion.

 

[Droogs]

Could you give a bit more info Bob. Would be interested as to what you use and proportions etc

edit

Also are you heat pressing them?

 

[doctor Bob]

Could you give a bit more info Bob. Would be interested as to what you use and proportions etc

Its UF resin, which is a liquid and a powder which is the hardener, mixed 5-1, volume rather than weight. The powder can be fast, medium or slow setting. so it ranges from probably 20 mins (fast)in a press to 3 hrs (slow).

So if your using fast you can't mess about.

 

[mbartlett99]

Could you give a bit more info Bob. Would be interested as to what you use and proportions etc

Its UF resin, which is a liquid and a powder which is the hardener, mixed 5-1, volume rather than weight. The powder can be fast, medium or slow setting. so it ranges from probably 20 mins (fast)in a press to 3 hrs (slow).

So if your using fast you can't mess about.

Bob where do you get it from - Essex Adhesives has something like that. I need a reasonable amount but not thee full 25kg they sell.

 

[doctor Bob]

I use Adkwik.

https://www.adkwik.co.uk/adhesives#...esin-c76/sort=p.sort_order/order=ASC/limit=15

 

[custard]

UF adhesives are an essential part of the veneering armoury, but for this particular job there are a few more reasons why mbartlett might be better off with PVA.

For a panel with no exposed edges PVA is perfectly adequate, this job doesn't require UF bond strength.

UF and Sycamore are a notoriously tricky combination because of the risk of green tinge, given that Maple and Sycamore are closely related species I'd be cautious.

Another issue with this particular job is that it's a figured Maple, consequently bleed through is a serious potential problem. There are solutions with UF (fastest possible hardner, adding heat, and most importantly thickening the mix with extender powder) but that's more expense and more complexity for a veneering newbie. Once you've thickened a UF mix with extender I much prefer to use a proper veneering hopper roller with a metal roller. I don't know what they cost these days but they're not cheap for might be a one off job.

The minimum quantities of UF are fairly high, and the shelf life is very short. So unless you've got a reasonable amount of laminating or veneering work you'll end up chucking most of it.

Once you're using UF with accelerated hardner and extender you'll have to clear out the hopper roller each time the vac bag is filled. And with the extender it's a nasty gloopy mess if you're working in a domestic situation. PVA on the other hand is a breeze, you can use a disposable foam roller and wallpaper tray, and in-between pressings you can wrap the roller and tray in cling film or just put it into a plastic bag and it'll remain uncured until the job comes out of the bag and you start on the next pressing.

I use UF regularly and wouldn't be without it, for curved work or laminations it's by far the best choice. But for this particular veneering job, especially by someone without much experience, I think PVA is the better choice.

 

[mbartlett99]

Fair play Custard I am convinced. Thanks all for taking the time, I think you've all saved me a lot of bother.

 

[doctor Bob]

UF adhesives are an essential part of the veneering armoury, but for this particular job there are a few more reasons why mbartlett might be better off with PVA.

For a panel with no exposed edges PVA is perfectly adequate, this job doesn't require UF bond strength.

UF and Sycamore are a notoriously tricky combination because of the risk of green tinge, given that Maple and Sycamore are closely related species I'd be cautious.

Another issue with this particular job is that it's a figured Maple, consequently bleed through is a serious potential problem. There are solutions with UF (fastest possible hardner, adding heat, and most importantly thickening the mix with extender powder) but that's more expense and more complexity for a veneering newbie. Once you've thickened a UF mix with extender I much prefer to use a proper veneering hopper roller with a metal roller. I don't know what they cost these days but they're not cheap for might be a one off job.

The minimum quantities of UF are fairly high, and the shelf life is very short. So unless you've got a reasonable amount of laminating or veneering work you'll end up chucking most of it.

Once you're using UF with accelerated hardner and extender you'll have to clear out the hopper roller each time the vac bag is filled. And with the extender it's a nasty gloopy mess if you're working in a domestic situation. PVA on the other hand is a breeze, you can use a disposable foam roller and wallpaper tray, and in-between pressings you can wrap the roller and tray in cling film or just put it into a plastic bag and it'll remain uncured until the job comes out of the bag and you start on the next pressing.

I use UF regularly and wouldn't be without it, for curved work or laminations it's by far the best choice. But for this particular veneering job, especially by someone without much experience, I think PVA is the better choice.

All true, and good points. I use UF for eeverything, but it's not for the faint hearted and inexperienced. Bleed through is a real issue and sometimes the use of pigments is necessary.

 

[mbartlett99]

Ta muchly for all the help it made this entire operation very easy indeed. 100 % success, no bubbles, no stress - that glue worked brilliantly Custard. I don't know why nobody on youtube suggests just inverting the work onto the platen but there you go. Each set took one hour in the bag rather than titebonds cold press recommendation of hours and without any of the stress of using titebond original.

 

[custard]

Nice job...and those look like very nice veneers!