How Do I Repair a Split Table Top ?

[RoyG]

I have an old Aussie Red Cedar Table that I've inherited from a family member. We're not sure how old the table is ... but guesses based on older family member's memories are that it is either early 20th or late 19th century - rough enough. The table may be old, but I don't think it falls into the valuable antique category. But it does have sentimental value to the family.

Unfortunately, the table top has split right down the middle for the full length of the table top (about 1.2 meters). Initially I thought that the split was along an old glue line, but as the split is not parallel to the long edge of the table, I'm guessing that it's unlikely to be a glue line failure.

I had initially been expecting that I could simply joint the edges of the split and glue the top back together. But after thinking that process through I realised that it would be hard to keep the ends of the table straight, and as the split is not straight, I may loose up to an inch of timber jointing the edges. Adding new timber into the table top would not be preferable as I'd have a very hard time matching the old Red Cedar.

So, my question is - What is the best way to repair a split table top ?

Thanks,

Roy

[Chief Tiff]

A photo would help!

Can the top be completely pulled apart along the split and simply clamped back together?

How thick is the top? Another possibility would be to rout out the crack with a narrow cutter, you'd want to use a template and guide bush for this.

Do you know what caused the split?

[Skew ChiDAMN!!]

I don't know about the "best" way...

...but so long as the crack is clean - ie. you can press the two halves back together almost seamlessly - you can simply biscuit the two halves back together.

The trick is to keep the biscuit slots parallel to the table top and each other, which means you can't use the cracked edges as references as one would when joining two dressed boards. (Unless they're miraculously flat and straight... in which case it probably is just a failed glue joint! ;) )

I place the halves on a large flat surface such as a good workbench and use that surface as the reference.. ie. I sit the biscuitter base flat on the workbench (depending on the machine, I may need to cut packers to place underneath to adjust the cutting height to centre of table thickness) when making the cuts.

Then it's just a matter of applying biscuits, glue and sash-clamps as per usual.

If the crack face is angled significantly then the resulting slots may not be deep enough for a full biscuit... but it's easy enough to trim the biscuit(s) down until it all goes together nicely. Cut-down biscuits will work just as well, provided they engage both halves' slots. After all, despite what many people thing, biscuits are NOT what holds the thing together; that's the job of the glue! All biscuits are for is to keep things aligned while the glue goes off...

Hint: Dry-fitting before applying glue is always a good idea, unless you like messy fingers. :rolleyes:

[RoyG]

Thanks for that feedback guys.

The top is 7/8" thick.

I believe that the cause of the split has been that the table top has been screwed directly to the table's rails with three screws up through each rail, via what looks like hand cut pocket holes. I think the split has occurred when the table top has dried out and shrunk, and couldn't move freely due to the screws holding it down to the table's rails. When reassembling the table, I'll mount the table top using a method that allows the top to expand and contract more freely.

I haven't disassembled the table yet. I plan to do that on Monday (29/12/2014), and will post some photographs at that point. I believe from looking at the split that it is full length and full thickness (i.e. that the table top is split into two separate pieces) - but that is currently speculation. I'll know the actual extent of the damage for sure in the morning after disassembly. If luck is on my side, then the split will turn out to be a simple glue joint failure - fingers crossed.

I don't own a Biscuit Jointer. Instead of using biscuits, would short slots cut with a 1/4" slot cutting bit in a router, along with home made splines, be an acceptable alternative to biscuits (I'd run the grain in the splined perpendicular to the grain in the table top (i.e. the grain in the splines would run across the split) ? If I use the table top as the reference surface for the router base, then I should get both the slots in both table halves in the same relative positions, and maybe the table surfaces will align when they're re-joined. I'll have to do a test run on some scrap to test the process.

I'll post some photos once I've disassembled the table in the morning. Thanks for the help.

Regards,

Roy

[rustynail]

This is a common problem with pocket screwed tops. If the joint is a natural split, I would release the hold down screws and see if the joint will clamp up. If so, just glue the joint and re-apply clamps. The need for biscuits or dowels is debatable. If it is a failed glue line then the faces will require cleaning before re-gluing. Cedar takes a good bond and a 7/8'' thickness would be easy enough to align without biscuits. Table clips or buttons would be a better method of re-fixing.

[Bob38S]

Thanks for that feedback guys.

The top is 7/8" thick.

................

I don't own a Biscuit Jointer. Instead of using biscuits, would short slots cut with a 1/4" slot cutting bit in a router, along with home made splines, be an acceptable alternative to biscuits (I'd run the grain in the splined perpendicular to the grain in the table top (i.e. the grain in the splines would run across the split) ? If I use the table top as the reference surface for the router base, then I should get both the slots in both table halves in the same relative positions, and maybe the table surfaces will align when they're re-joined. I'll have to do a test run on some scrap to test the process.

I'll post some photos once I've disassembled the table in the morning. Thanks for the help.

Regards,

Roy

Check out posts 5, 8 and 16 of this thread.

http://www.woodworkforums.com/showthread.php?t=129146

Before I had a biscuit jointer this is what I used, a little slow compared to the machine but just as good.

However, as others have said, I don't think it will be needed in this particular case.

With regards your fix, ensure that the crack surfaces are very clean, no dust, wax etc and use a good glue like Titebond III.

Re the cleaning, being an old table I really hope that no one has used any product such as a certain Mr Shine, yes, I do know the real name but can't use that 4 letter word in the open forum, this particular product and similar is very difficult to remove especially if it has soaked into raw wood.

[RoyG]

Ok - Here 'tis .......

The first photo is the general overview. You can clearly see the split across the length of the table top. I should have had a closer look in daylight before making the first post in this series, as when viewed in daylight it is obvious that the split is along a failed glue line, so the fix should be somewhat easier that I originally anticipated.
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The next photograph shows a close-up view of the split. To answer one question asked earlier; the split is complete - the table top is in two separate pieces.
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The next two photographs show more detail of the condition of the table top. As you can see, the table has been well used, as an office desk in a business until the mid 1960s, after which it was used as a home desk.
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Lastly, is a photo of one edge of the table top showing where a large piece is missing, and also showing small checks or cracks in the end grain of the top.
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So, my questions are:



I plan to use a scraper blade to gently clean up the old glue joint prior to re-gluing - am I on the right track with that approach ?. I won't bother with biscuits or splines or similar based on the thickness of the table and the advise received so far. I'll just glue it up on the workbench using the table top in contact with the workbench top to get the table surface level. I had planned to use Liquid Hide Glue for the repair. Someone suggested Titebond III - any specific reason ?
As regards the piece missing out of the end of the table top, I don't plan to do anything to repair that damage. But I would like to stabilise that area, and to also stabilise those few end grain checks/cracks if possible. Any suggestions regarding whether stabilisation is necessary or possible ?
I'll re-attach the table top using buttons instead of the current 100 year old pocket holes - hopefully that will prevent the tabletop splitting again in my lifetime.
As far as rejuvenating or restorating the tables finish ..... As you can see from the condition of the table top, there is plenty of patina etc that I'd like to retain, especially where people have rested their hands on the table top. But there is also some nasty scratches that go right through the finish. Any suggestions regarding how to treat the rejuvination or restoration of this table top. The table's underpinnings are in much better condition that the top, and may respond to just a clean and a new top layer or two of fresh shellac. I would like to stick with Shellac as the finish if possible.


Thanks in advance for everyone's input. It is greatly appreciated.

Regards,

Roy

[Xanthorrhoeas]

When you get the top apart and clean out the joint you will almost certainly find that it was originally glued with hoof and hide glue (also called "pearl" glue and hot water glue by some). New adhesives do not take well to that, but new hoof and hide glue will take to it very well and give a very strong bond. What I would do is to clean the glue surfaces with a rag dipped in hot water then apply new hide glue before clamping - no biscuits/dowels etc needed. If you don't have any hide glue and a glue pot there is a Titebond ready made Liquid hide glue that Carba-Tec sell. I have not used it (just ordered a bottle to try in fact) but they claim that it works the same way as hot hide glue/pearl glue. It is the most sympathetic adhesive for an old piece like this.

I also agree that you do not want to lose the patina. Even though some of those scratches are deepish I would just polish over the top with shellac and live with them. If there isn't much finish you could try to steam the worst out with an old steam iron. Wet the scratches with tap water and let it soak in a few minutes then run the steam iron over briefly. I sometimes use a wet fine cotton rag and iron that on to the surface. But, if there is shellac left that will mark it and leave the fabric pattern in the finish, which you then have to clean back with some metho:oo:. You would only do that if there is no or minimal finish and you are going to re-polish the whole top afterwards though. Otherwise, just live with the scratches, which will not be so obvious after some brown shellac (preferably not orange flake shellac IMO) and a coat of black furniture wax polish, well rubbed in/rubbed off to give it a lovely soft sheen.

Hope this helps.

Regards

David

[Bob38S]

Titebond III - when dry is "waterproof" and should not be affected by any humidity or spills on the tabe. Have not had any failures with this glue, if you try and force a failure, in my limited trials, the timber has failed not the glue.

Have you determined what the current finish is?

Old red cedar- it will take more time and effort but consider a restoration rather than just a fix.

Wth regards the dings and scratches, as you are going to refinish the top rather than repair bits, consider steaming the top. By this I mean, double up an old flannel sheet, wet it, not dripping but very wet, lay on the surface and let it sit until the surface has taken up some of the water. Take an iron set on hot steam setting and iron over the sheet. This will cause the dings to rise as the compressed wood fibres will expand, the scratches will swell and rise but as timber has been removed they will not necessarily rise to the surface but will not be as deep as they were. This would mean that you wouldn't need to remove as much material in your surface preparation. If you wish to keep the "distressed" look this process will also work as you wouldn't sand it as much.

Just some thoughts.

[Bob38S]

Apologies David, I didn't see your post which must have come in while I was typing, interesting your take on steaming, I have not done it that way before.

[Skew ChiDAMN!!]

This is a common problem with pocket screwed tops. If the joint is a natural split, I would release the hold down screws and see if the joint will clamp up. If so, just glue the joint and re-apply clamps. The need for biscuits or dowels is debatable.

:yes:

I'd like to point out that there is rarely ever any "need" for biscuits, splines, etc. They do, however, make life easier in that they mitigate minor problems with glue creep and fiddly alignments while tightening clamps. If done properly, of course!

[RoyG]

I removed the table top this afternoon, and got a surprise when I separated the two halves of the table top.

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The table top definitely split at a glue line - the easy way of telling being that the joint has four dowels in it. I think that the dowels are probably original as they look like hand whittled dowels, rather than more modern shop bought machine made dowels. The dowels are in good condition, and the glue holding the dowels has failed, so I'll be able to get them out and re-use them. I'm pretty sure that the glue is hide glue. I scraped some glue residue from the joint, and the glue residue softens and gets sticky in warm water. I'll use Titebond Liquid Hide Glue for the repair as I have some on hand - I use it because it gives me more assembly time.

The remainder of the table's structure is fairly unsound. Three of the four legs have failed glue joints in the mortice and tenon joints between the rails and the legs. So, Tuesday's job will be to complete the disassembly of the legs and rails, and fix up the failed joinery.

I'm surprised at the number of nails used in the table. The drawer guides, draw stops, and quite a bit of other secondary structure under the table is nailed (no glue visible in the joints). And when the drawer guides etc have inevitably loosened up at various times over the last 100 odd years, people have just banged in a few nails. Anyway, the drawer guides are really badly worn, and two are badly split and damaged from previous numerous nailed repairs, so I'll need to scarf some new timber into those drawer guides, or maybe make new ones if I can get hold of some red cedar locally.

It's interesting to look into the materials that were used.

The first interesting bit is the material that they've used for the table top. Two boards, each 15 inches wide. I wish we could still get Aussie Red Cedar boards that wide.

The other interesting bit in the materials were used for the drawer sides and table rails. It looks like they've used 3/4" thick Red Cedar tongue & groove boards - I'm guessing they were floor boards, or maybe wall cladding boards. In the following photos you can see on the top of the drawer side where they have planned off the tongue on a drawer side and left just a hint of the tongue. On the other photo you can see the groove still in the bottom edge of the drawer side. There's no old nail holes in the timber, so I don't think the timber was recycled - just floor boards used to make drawers etc.

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A question for experienced restorers of Australian antiques...... Does the use of so many nails in the secondary structure, and the use tongue & groove boards for some parts suggest that this table was built by a hobby woodworker, or was some commercially made furniture from around a 100 odd years ago built this way ?

So - that's the update. I'll update this thread when I get a bit further down the track.

Thanks again for the valuable input from everyone. Be assured - your input is greatly appreciated.

Regards,

Roy

[Xanthorrhoeas]

Stylistically the table having the corners cut off like that suggests later than I thought earler. Possibly 1910 to 1930. I have not seen the use of modified tongue and groove boards like that in any professionally made piece. However, the nails were probably mostly added later. My suspicion is that it was an amateur piece rather than commercial. Only my guess though.


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