OK, here comes another one about the queen ann table :)
I'm going to use MDF for the top with cherry veneer .. i bought the veneer sheets at Woodcraft .. I actually got these big long sheets 6"x10ft ..all taken from the same board and just stacked together and wrapped .. there's no adhesive backing to them, just the wood ..
I was told that I can use regular yellow glue to apply the venner to the top (after jointing and masking, etc.), then roll it and make it true to the mdf, then I'm going to put a big sheet of mdf over top as a clamp to hold it down while it dries .. is this ok? I've heard people say they like to use contact cement? should I use that or is yellow glue OK? I figured it would be because it has no backing on it ..
You are quite correct in your thinking.
How big is the table top ?
That will have a big bearing on the best method to lay down the veneer.
Rather than wax lyrical on different methods come back and we'll talk !!
You can use Contact adhesive but it has a number of pitfalls ready to trap the unwary. The two that can cause most agida are small bubbles that are difficult to get out and which may cause splits in the veneer if you are too aggressive with your roller and probably more significantly interaction of the solvents used in the finish you propose leaching through the pores in the veneer softening the contact adhesive and lifting the veneer ...ugh nasty.
Water based finishes would minimise this risk but there is no guarantee...certainly Shellac or other alcohol based finishes even if used as a sealer would almost certainly lead to disaster.
But stay with it kiddo it's not nearly as hard as it may sound and your ability to go on and experiment with veneer faced surfaces will open up a whole vista of exciting and showstopping projects.
So come back with a few details on size shape etc.
Check out www.tapeease.com for your future veneering supplies. I have been using what they sell as NBL (no black line) veneer with great sucess. It is a wood back veneer and comes in 4' x 8' sheets.
I will admit to having used contact cement in the past with great sucess, although if you research veneering on the web you will find lots of folks that say contact cement is the wrong way to go. Most of the veneering experts (those that are at least good enough to write books on the subject) tend to recommend using a hot hide glue. I have not tried this yet although will likely give it a shot on my next veneering project. One of the biggest problems, other than those already mentioned, with contact cement is that once it's down- it's down! There is no moving around of your veneer if itp
Limey ditto's on the yellow glue in this case. With contact cement you don't get much opportunity to line things up. Yellow glue will afford you this. I would recommend against titebond II for this and go with std titebond, all tech stuff aside if there's going to be moisture involved go with straight titebond. I learned this from stripping my canoe.
If it were a single sheet and trimmed with a flush bit I'd opt for contact cement.
Oh Sean...your entering the Indy 500 after a couple of driving lessons why did I think this was going to be easy !
The size you want to veneer is beyond the scope of a lot of professional shops and the only time I tackled a job of this size was when I did an "honours board", 2 actually, and this used 3/4" MDF..at that time a product called "Glu-film" was available and it was like a sheet of Hot melt in 4' wide rolls and activated with heat from a domestic iron...it took me two weeks and and a lot of sweat and on reflection it would have been far more sensible to have bought 3/4" furniture ply pre-veneered. I fear that you would be strongly advised to do the same...sorry.
As we've come this far and I gathered together all the accoutrements I'll explain the process so that if you want to try something of a more modest size you will have the information. It will become evident as you follow the process why 6'X 4'would be challenging to say the least. ... Why was I thinking Coffee Table ???
First you have to dress the Veneer... It is rare that the figure will look right if uyou flip alternate sheets to get a pleasing match.
The first task is to take two sequential sheets and open the top one just like opening the pages of a book..not surprisingly this is called a "book match" pattern.. Now adjust it so that the pattern at the join looks right you may have to jiggle the top of one sheet out and also the bottom of the other to get the grain to look right.
This may only be an 1/8th of an inch but it makes all the difference.
When you have established a good match you will probaly have an overlap of the two sheets.If it is less than a 1/4" move the top sheet in a parallel direction until it is.
Take some Map Pins (sometimes called veneer pins at 10 times the price!!) and pin the the sheets to the workbench at 9" intervals so that they cannot move..(first fly in ointment you will need a BIG workbench or sheet of ply. The MDF backing is great for the underlay but you can't push pins into it !!).
Then you will need a 6' straight edge mine is steel and 48" long and was expensive..you could use aluminium and there are several good ones out there but you are almost certain to damage the edge when you proceed to the next stage...Cutting the edge.
Lay the straight edge down the centre of the overlap..without disturbing the veneer.
For actual cutting at a pinch you could use a Stanley knife but following the straight edge rather than the grain of the wood is next to impossible. Plus a knife will leave a small but perceptible ridge ...no young man you really need a veneer saw pretty cheap though at about $7 ...you will notice that it has a very slight curve on the blade and this allows a rocking type cut so that holding the saw at 90% to the side of of the straight edge you can saw through the top veneer and mark the underneath one. take the piece away and proceed through the underneath one. Voila you now have two butting perfect veneer edges.. Now you have to tape them.
Taping the joints uses gummed paper tape the sort you licked before Scotch tape was around..You'll be doing a lot of licking so unless you have a real liking for adhesive it's best to use a saucer with a small sponge.
You need veneer tape Paper backed adhesive tape some times perforated with holes so you can see what's happening to some extent.
You can use brown packing tape(not the sort with the cotton reinforcement though)but the reason you use tape is that when the tape dries either saliva or the water from the sponge. The tape shrinks and pulls the two edges together so tightly that like a good hairpiece you can't see the join. Packing tape is very much thicker and shrinks more so it can cause the two edges to buckle up ..that's when experience comes in and you leave a small gap so the stronger contraction of the tape pulls them together but no further...better get the proper stuff eh?.
We haven't got to the hard bit yet !!!!!
So now you have a big sheet of veneer all taped and I reckon that with the width you have you are going to get(with alignment wastage)
9 or possibly 10 joins..pretty scary..told you a lot of professionals would leave their breakfast in their skivvies if asked to do this...
AND we haven't got to the hard part yet.
OK next task is to lay the veneer down..
Water based PVA or Hide glue ?
glossing over the issues of glue creep which is a contensious issue when considered in conjunction with veneering.
Cold glue....Yellow glue Titebond type 1 yeeesss..but I would go with a lower solids white glue or dilute the Titebond ever so slightly.
Even on an area half your size you you will have to work like the clappers to get it clamped up..or get a group of competent buddies to assist...don't forget to factor in apres coitus beer costs.... you only have a limited time to get everything clamped up and the more moisture..up to a point. the longer your working or "open" time will be.
Method is two prepare your press ..two sheets of 3/4 MDF... two sheets of plastic film to go against the MDF..Building moisture membrane is good .. 3 layers of newspaper to cushion and absorb moisture..but if you don't want to read an inverted print of the Headline on your table the you have to wait till Wally World has a special on the expensive Paper Towels as you need a good 2 layers on top of the newspaper to soak out the bulk of the moisture from the glue..big ain't so beautiful now HUH!
So pour your glue into a paint tray dilute it a little more, get a foam roller and "size" the substrate (MDF)...substrate sounds far more technical don't you think.... When this is dry(30mins or so depending on temperature) give it a good going over with the full strength stuff..at this time you should have taken a bathroom break, 6 Valium and lock any children or accident prone adults safely away so they can't distract you..same goes for your buddies. Take phone off the hook and with a man at each corner position the veneer tape side up..layers of kitchen towel then newspaper then poly sheet then other sheet of MDF and carefully lower onto the prepared "bed" WITHOUT disturbing the veneer.
Tighten up your cauls from the center out..one ever 8-9 inches...12-13 if you are feeling lucky...OOPS I forgot to mention cauls didn't I.
Seepictures of my home made ones which take a 12" panel..you will see if you look closely that they have a very slight crown on both inside faces...this is so that when tightened down the pressure is applied first to the center and then to the outside as the wood is forced together until you can't get your finger nail under the edges.
Ash is an ideal wood for cauls ..I'm cheap and used strong pine..they have lasted well but you hear lots of groaning on the last few turns of tightening..one day there will be a loud crack and a break which will jeopardise the glue up..but hey I like to live dangerously.
Tighten each side down evenly..In your situation you will need to have a pit crew mentality so that after the center one is tight the crew move to the left while simultaneously a second crew start on the one to the right of center and all four have to be trained so that all four finish at roughly the same time..then move outwards again tikll all cauls are tightened..BUT this brings up second fly in ointment..your span is 4 feet and even carefully made ash bearers won't cut it over about 18-20" so you will have to purchase a large quantity of wide veneer clamps (muchos bucks) the ones that have top clamps that apply pressure from the top as well...more buddies..more beer. Only attempt this if you can complete this assignment in less than 20 minutes..suggest you enroll whole team at Nascars pit crew training school.
So that approach is not really feasible..but would you have believed me if I just said this from the outset...
What about hide glue.....
You will need a water jacketed glue pot and a camping ring or electric element to melt the glue and maintain it as close to 140 degees F as possible. If you want to get rid of unwelcome guests or neighbours let it go higher and start to char..The stench is the most obnoxious odour imagineable..however its a good method of determining that the water jacket has boiled dry.
There are themostatically controlled pots a bit like slow cookers that have become available but yes you guessed it muchos bucks.
With your specially designed glue brush(see pictures) BTW these aren't cheap either but are necessary you spread an even layer of adhesive one veneer strip wide . fold the veneer back on itself so that the underside of the first veneer is the one you lay... Your Buddies hold upthe rest like a curtain and you squeegee the first strip down with your veneer hammer..either purpose made with brass blade or home made with sharply rolled stainless steel blade (see pics) it goes without saying that homemade is a LOT cheaper.
You repeat this exercise 9-10 times depending on the number of strips.
Over a six foot length you have to work very quickly with a ready supply of spinach... muscles after about 2 strips will make Popeye very envious...better get a trained relief man to take it in turns..thats the trouble with America all sports apart from Soccer which few play are non continuous.. ahtletes here are not Stamina conditioned..except Lance Armstrong so you won't do well if you need a break after every couple of minutes. I digress.
When you are done you will probally need to check the joints.
To check for air pockets rapidly flutter the fingers nail side down over the area you will immediately hear where the veneer is not adhered...get a damp clean cloth and pad the area and a warm domestic iron. reactivate the adhesive and squeegee down. You can do this a couple of times but the glue quickly loses it's tackines and becomes ineffective
Soo if you got this far collect 10 woodworking credits towards your masters degree...and I don't think I need suggest that a pre-veneered sheet of 3/4 " sheet of Cherry ply would be my recommendation :+
However on the one serious vein all this difficulties rapidly reduce as you start on smaller stuff..You will need a few bits of specialist equipment that can be purchased from many veneer suppliers.. Constantines in Florida have a catalogue and are a good source.
I think I covered everything and am wondering if this is the longest ramble on the forum..all to say don't attempt this at home..
Sounds like you've done this before!! How long did it take you to write that? I would imagine you had a few beers and smokes in the process! lol.
I was thinking about it, and I know I should've gone with a pre-veneered sheet of Cherry Ply .. i'm going to do that for the hutch that i'm gonna build next ..
OK, in reference to some of your post .. I think my application will be a bit easier than described ..
#1 .. I don't have the "book" of veneer ... so I don't have to do that mutch matching and jointing .. I have about 15 sheets of 8" x 10ft pieces ... that will make my life a lot easier ..
the nice thing about having the 10ft pieces I don't have to match the grain lengthwize, it's all from the same board too so the grain will be the same on each sheet ..
#2. The clamping ... I have a project plan of a guy doing a 48" x 60" table in veneer ... from a dining room tables plan book I got at woodcraft .. he joined with masking tape, and used a couple of sheets of melanmine as weight on top of the veneer after rolling out bubbles ... melanmine doesn't stick to yellow glue .. i tried, works wonders ..
#3. Edging .. I got a veneer edging knife from woodcraft as well .. i tried it on some scrap .. cut out a perfect edge around the scrap piece ... that will make it somewhat easier too ..
I've got enough veneer for extra, and some mdf to test this plan with before i do the correct application ..