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I have an oak kitchen table that needs repair. The oval top is supported in the center on a turned wooden column resting on four curved legs (very common furniture store style table). The center column is approx. 10 inches in diameter, turned from an octagon glued up from solid oak slats.
Stress from leaning on the outside edges of the table top has caused the column to split along the glue lines several times. I’ve repaired it twice by taking off the top, prying the glue joints open as wide as I dare, scraping as much old glue away as possible and re-gluing and clamping with yellow wood glue. Each repair has lasted for six months to a year, and then the column splits again.
Short of throwing the table away in frustration, I’ve thought recently of trying to glue the column with epoxy or polyurethane glue, but don’t have much experience with either.
Does anyone have any advice?
P.S. I live in Vancouver Canada where the climate is temperate, with fairly stable temperature and humidity. I don’t think changes in humidity is the culprit, more likely it’s my kids crawling all over the table when they know they’re not supposed to.
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Ken: you have answered your own question. Make the best repair that you possibly can Then-------Lay down the law to your children. PAT
*Hi Ken, Interesting problem, and I think Major has a solution for you. However, I wonder if there isn’t another underlying problem. Can you provide more details about the table’s construction? Size of the top, thickness of the wood used for the column, type and age of the glue used. How old is the table, fairly recent or an antique? What is the thickness of the wood at the glue line? When the joint fails, is the glue failing or is the wood adjacent to the glue line failing, are the failures along the top or bottom of the column? Is it always the same joint that fails or have several failed over the years. Does the joint in question lie along a major or minor axis of the top? I know, so many questions. I wouldn’t throw the table out yet. Worst-case scenario would be to make a new column and correct any flaws that you think you find in the current design. Of course I am assuming that you have made the table and not bought it from a furniture store. Yellow glue should work fine in this application. You could also try pocket screws along with glue if you can place them out of sight along the top or bottom of the column. If you can provide answers to any of the questions above I can try to offer some more suggestions.Bob
*BoB: Enough of the tongue in cheek to Ken. It would seem that the manner in which the top is fastened to the column is the main problem. When a downward force is placed on the edge of the top,it acts as a lever to place a sideways force on the center mounted column.the severety of which depends on the distance from the edge of the table to the closest edge of the column.These octagonial columns,once the turning is completed,are left with a very narrow glue surface. I have one of these old tables in my dining room that belonged to my wife`s mother.It is an extention table that when fully extended, is 42X58inches.The top 3inches is not turned but was left in the original 8 sided glueup.There is an 11 X 24 inch board on top of the pedestal,screw fastened to the top of each of the column slats. this is the mounting for the top extention assembly.A very strong and durable joint to the column. It is possible that the design and construction of Ken`s table is more to blame than the children.PAT
*Thanks for your help so far, both Bob and PAT. I've been reading the messages in Knots for some time, but this is the first question I've posted. I'm pleased and impressed with the help that members of this community give to each other. Great stuff.To answer some of your questions, the table is about 5 years old. The column is made from 3/4 stock, with both the top and bottom 4 inches left octagonal. The bottom so that the four legs can be attached to a flat surface, and the top so that the table top can be attached. Your description of the top construction was bang on PAT. There is an 11x18 board made of 1 inch plywood screwed to the top of the column. The table is 42 inches round, 42x54 when the center leaf is added.I was thinking of pocket screws too Bob. I have a portable jig that I could use. It would be tight and awkward, but would probably fit. My question still is should I stick with yellow wood glue (reinforced with pocket screws perhaps), or would I get better results with polyurethane or expoxy. The failure is happening mostly along the the glue line although some joints have failed on the wood beside. Thanks again for your help.Ken
*Hopefully someone else will hop in here and lend thier opinion, Sgian or Kim perhaps? Anyway, thanks for clearing up the column design for me. I am still having trouble understanding why a long glue joint in the column would fail because something applied some force at a point along the perimeter of the top. I would think that if the top, or cleat, were screwed into the end grain of the column the screw would pull out before breaking a glue joint. Screws do not hold as well in end grain as they do in long grain. Then again, I might be misunderstanding how the top is attached. I would also check the joints that hold the feet to the column, I would think that they would also loosen up with the use the table was getting. Forgive me here, but could the joints that fail be poorly made? A very slight error in the angle while cutting the pieces for the octagon could lead to a loose fitting joint and yellow glues are not good in gap filling situations. . If the joint failed within the glue line then the glue is suspect. It could be a poorly fitting joint or bad glue. Did that bottle of glue freeze and thaw at some point or was it more than a year or two old? If it is taking wood fibers with it then the glue was probably ok. You didn’t mention where the joint is failing, is it at the top, middle, or bottom of the column. If it is at the top of the column, you can place pocket holes and screws within an inch or two or three of the top on the outside of the column and they will not be seen except from under the table. Generally if one is under a table, one shouldn’t be worrying about screw holes anyway.If you decide to make a new column, you could pocket screw the slats together from the inside and have just two un-reinforced glue joints when you glue the two halves together. Make them in pairs and then screw two pairs together with a flexible bit extension on your drill. You might even be able to get the whole thing together that way. Sorry to ramble on here but I just think that there is something that is causing the problem rather than leaning on an edge. Then again I do not have any kids, and recollections of my own childhood antics are generally more reserved than those of my older siblings. Let us know what you decide to do, or if you find anything to shed more light on the topic. Yellow glue should work well, especially if you back it up with a few screws. Bob
*If memory is working tonight, I've read that yellow glue (any many if not most others) will not stick to dried yellow glue residue. Repair articles have said it is necessary to scrape or sand off all dried glue residue unless hide glue was used - new hide glue will stick to dried hide glue.If the joint failed, I would suspect either a poor joint, bad glue, or poor practices. If the wood failed then the table design may be inappropriate.Good luck.
*In case anyone is interested, I repaired my table this past weekend using pocket screws and a bottle of brown cabinetmaker's glue, formula 202GF that I picked up at Lee Valley a few months ago. I bought this glue because I was intrigued by the blurb in their catalogue that says "The high solids content makes it a good "gap filler (that's where the "GF" comes from) for loose joints."I tried it several months ago on a different project. It worked well, but I didn't like it much because it's a fairly thin formula and flowed too easily. So I put aside, and went back to tried and true Titebond.After scratching my head for a few days trying to decide how to repair my table, I remembered that bottle of glue. For this application, the thinness of the glue and the easy flow rate was exactly what I needed. I drilled the pocket screw holes, scraped out as much old glue as possible, and poured the new glue down the cracks in the column. It flowed much further than the last repair, at least a foot down the inside of the column. In went the screws, on went the clamps, and I left the whole assembly to dry overnight.The next morning I took off the clamps and it seems tight and solid. Now if I can keep my kids off the table, it might just last.Thanks everyone for your advice, and I hope this helps anyone else who is having a similar problem.
*Hi Ken, Thanks for the update. I find it interesting that the GF glue is lower viscosity and higher solids. One would think that by increasing the solids level the viscosity would increase also. If the glue was setting around for awhile, it could have seperated a bit and there might be a thicker bit at the bottom of the container. Did you stir the glue before using it, or just take it off the top? I deal with these sort of things where I work and I am just curious. Bob
*It's a fairly fresh bottle, I've had it for less than six months. When you leave it sitting upright, the solids do settle to the bottom of the container. When I know that I'm going to use it, I will turn it upside down a couple of hours before use, and then give it a good shaking. I've used a least half the bottle, and I haven't noticed any change in consistancy from project to project, so I guess I've done a good job of mixing it up before use. One other advantage is that it dries brown, so it's easy to see and scrape away when the clamps come off.
*Hi Ken,I can only speculate on why the original column failed but I can tell you why the repair is only working temporarily. These sorts of columns are pretty difficult to make. The proper way is to cut all but the last piece then cut the last piece to fit. However, if you're off even a little bit you'll leave a gap. PVA only works when the work pieces are perfectly aligned: it's really not a gap filling glue. Probably the best glue for this application is epoxy. It's gap filling qualities make up for the inevitable failings in the joinery. If the column were made properly it shouldn't split: your kids are off the hook. A hollow column should move enough to account for seasonal wood movement.The reason your repair is failing is that it's impossible to clean out the joint adequately and get joint quality surfaces back. The proper way to make the repair is to cut the column in half (where one of the kirfs takes out the failing joint), joint both halves, then glue the halves back together using epoxy. This is not a trivial repair!One last thing. The life span of PVA is only about 6 months. If it's separating, it's past its prime - you've only had it for 6 months but it may have been sitting on the shelf for much longer. Get a new bottle for your next project.Hope this helps,Kim Carleton GravesCarleton Woodworking
*How about putting glue blocks inside the collumn?
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