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Doc Carver
27th February 2006, 11:28 AM
Around 10 years ago I was lucky enough to come across 3 slabs of New Guinea Rosewood 350mmx110mmx2700mm. I had them split in half so I now have 6 @ 350mmx50mmx2700mm. I am going to make 2 dining room tables for my 2 children with a book matched panel in the centre of the table and 2 175mm pieces each side of the centre panel. The figure in the timber is superb so the tables are going to be very simple in design to highlight the timber. I would be grateful for advice on which glue to use to glue up the table top. Thank you.

Dean
27th February 2006, 11:59 AM
I haven't glued anything as large as a table top with NGR, but I've glued up a few smaller assemblies using NGR and the regular Titebond II yellow glue seems to work just fine for me.

Termite
27th February 2006, 12:30 PM
Doc, its a fairly big glue up job so you need a glue with a bit of working time, and it must be of the type that will not creep with time.

My suggestion would be Titebond Polyurethane, up to 20 min working time, non creep, waterproof and non toxic. Not cheap at around $30 a bottle but it does a very satisfactory job. There are cheaper poly glues about eg. Selleys, but they tend to have a shorter working time.

Rocker
27th February 2006, 12:44 PM
Doc,

The trouble with using PVA glues like Titebond is that they are subject to creep, particularly if the edges of the boards are not perfectly jointed, so that you may find that, after the creep has occurred, there is a noticeable ridge of glue along the glue-line. I believe that, to get best results with a table top, it is best to glue it up with an epoxy, such as Techniglue, which is not subject to creep. Techniglue (obtainable from Carbatec) has the advantage that it is a gel, and so is less messy than some other epoxies, and it also has a longer working time than PVA.

However, it is still feasible to use PVA, if you take precautions to avoid the creep. That is, you need to ensure that the edges of the boards are perfectly jointed, so that they fit together with no discernable gap, and also, you need to leave a significant time, say a week, between the glue-up and final sanding and application of the finish.

Rocker

AlexS
27th February 2006, 01:44 PM
I've used yellow glue with no problems on a smaller NG rosewood tabletop, but heed the advice of Termite & Rocker regarding glue-up time and creep. Haven't used polyurethane, but Techniglue would be fine.

Woody1
27th February 2006, 03:24 PM
Doc
I was in PNG about 22 years ago and I also was lucky enough to get a couple of slabs of PNG Rosewood.
Swmbo and myself built this Hall Table and it was glued together in approx 100mm widths with Araldite 2 part with 50% equal mix. This is all that the local furniture maker used for his Knock Down Furniture which he built and sold.
After 22 years and the table coming from Bougainville PNG,Gove NT and finally Gladstone QLD it has shown no signs of coming apart.

Woody

Andy Mac
27th February 2006, 03:49 PM
I've done quite a number of large refectory style tables in various timbers but not the one you've got. We always used epoxy (Araldite) with biscuits, but make sure the pieces are jointed exactly, and square.
Good luck, sounds like a great project Doc!:)

Zoot
27th February 2006, 03:49 PM
Doc,
I would have a look at a slow setting glue that I use in boxmaking and small joinery ... it is called Multihesive by Preproducts

It is made from Styrene Acrylate, dries clear, sticks to almost anything including timber, metal, glass, leather etc and what suits me is that it has about 30 to 90 minutes setting time ... plenty of time to assemble.

The manufacturers claim that this glue supercedes PVA! I think that they said it was water resistant, but not waterproof ... whatever that means!

I bought it at Home Hardware, but I think it is available elsewhere as well. I posted a copy of their description in this section of the forum about 3 weeks ago, but have not worked out to give you a reference to it ... you may have to look back under Styrene Acrylate Glue.

Cheers,

Zoot

http://www.woodworkforums.ubeaut.com.au/attachment.php?attachmentid=18475&d=1138675409

Dean
27th February 2006, 04:23 PM
Umm yeah I should have mentioned in my original post that all my glue ups using NGR and Titebond II had perfectly jointed edges, with the larger glue-ups also using biscuits. No problems here thus far, but if you want the ideal glue-up, go for some of the glues the others have mentioned :)

kiwigeo
27th February 2006, 04:48 PM
If using Titebond or other AR glue give the rosewood a light wipe with meths or acetone to leach out some of the oil. Rocker mentions creep while gluing up.....I cut risk of this down by clamping up with stops and cauls to stop wood moving once its glued. Plenty of clamps and pkenty of cauls and stops.

Cheers Martin

Rocker
27th February 2006, 05:27 PM
Kiwigeo,

The creep results not so much in the boards becoming misaligned, as you imply, but in the formation of a ridge along the glue line. The ridge forms, I believe, because the PVA creeps out of the joint, since it is subject to plastic flow, particularly if the joint does not fit perfectly and the glue line is therefore thick. As I suggested in a previous post, the effect can be lessened by leaving some time between glue-up and final sanding, so that an incipient ridge is sanded away.

Rocker

scottyk
27th February 2006, 08:49 PM
WEST System or HT 9000 Epoxy with filler powder added.
The above products make anything with the word polyurathane on the label look like Clag.
With 50mm of bonding area for your slabs the joint will be stronger than the wood itself. Never ever come apart.
I would like to put a friendly question to the woodies out there as to why people dont use these products as standard?
Scottyk

Auld Bassoon
27th February 2006, 08:56 PM
Hi Doc,

Send the slabs here, and I'll experiment for you ;) :D

Auld Bassoon
27th February 2006, 09:05 PM
I would like to put a friendly question to the woodies out there as to why people dont use these products as standard?
Scottyk

Hi Scotty!

For myself, I tend to use the Garret Wade 202 PVA as it is a good, simple and reliable glue for most tasks. Being water soluble also makes clean-up pretty straightforward.

I do use epoxies (generally from West) for some glue-ups, but frankly I find that the mixing and general mess is just too much for most simple jobs. After all, the joinery should be doing the mechanical attachment, not the glue - excepting, possibly, table top or panel construction.

Cheers!

Doc Carver
1st March 2006, 12:36 AM
Thanks for all the advice. I really appreciate this forum and the knowledgeable people who contribute. It is a great help.

Regards

Lignum
1st March 2006, 12:54 AM
After all, the joinery should be doing the mechanical attachment, not the glue - excepting, possibly, table top or panel construction.
Cheers!

Perfectly summed up:)

IanW
1st March 2006, 09:14 AM
If using Titebond or other AR glue give the rosewood a light wipe with meths or acetone to leach out some of the oil. Rocker mentions creep while gluing up.....I cut risk of this down by clamping up with stops and cauls to stop wood moving once its glued. Plenty of clamps and pkenty of cauls and stops.

Cheers Martin

Martin - NG rosewood is not a true rosewood, i.e. not a Dalbergia, and doesn't seem to be at all oily, so I doubt you need bother with solvent pre-wipes. I've glued it successfully with PVA glues (about 8 years for the oldest piece, and no problems so far). I've also used hide glue, and melamine glue (for benchtops) with no problems. Haven't tried any of the others mentioned.

The 'creep' Rocker is talking about isn't movement during glue-up, it occurs afterwards because PVA glues are thermoplastic - they soften when warmed. If there are any tensions in the joint, it will move or spring - a nice Qld day is sufficient to soften most PVAs.

Any joint can develop some tension, because you can never predict exactly how wood will respond to seasonal moisture movement, but you can go a long way towards eliminating or minimising it by using well-acclimatised material, jointing carefully, and don't force a poorly made joint closed with clamps! Cauls are good, they distribute the pressure evenly, but you should only need light clamping pressure to close a good joint. (So the gurus say, but who hasn't used excessive force on occasion to close that one little annoying gap in an otherwise perfect join? ;) )

One thing I have noticed about NG rosewood is that there is often a lot of tension in its sapwood, (there is some tension in any sapwood) and I would be very careful to remove any from the join areas on a tabletop for that reason.
Cheers,