The easiest will be to use an epoxy product. If the wood is free(or mostly so) of old glue, you can use regular wood glue(the yellow kind).

Either way, the joint needs to be clamp-ed until cured/dry. Rope can be used, as can duct tape(with paper on the legs so the tape does not stick to the wood), or even a belt.

Just make sure the legs are square(measure diagonally and even the measurements).

This winter some "captains" chairs got desperately loose, so I grabbed what I already had out, fish glue, and used that. Hot hide glue was not an option because of how cold it was ATM.

The fish glue takes two days to really harden, but it really did the trick, it was fast, easy to clean up, and most importantly, it is reversible, unlike epoxy.

http://www.columbiaorgan.com/col/glues.htm#Fish%20Glue

Casey

The most important decission in chair repair is how far to go with disassembly before begaining reassembly. If anything is loose but not coming apart it pay's to go ahead and pull it apart so it can be tightened. The only glue which fills gaps is epoxie but as already mentioned,you might never get the joint apart again if needed. There's multiple ways of tightening joint during assembly,wood shavings and wood flour are two of my favorites. Shavings and hide glue are best if you want the ability to take it apart in the future. Wood flour and yellow glue are easy and make a reasonably sturdy joint. There's a joint where tenion is split and wedge inserted that imo should be attempted only by pros. As someone else mentioned,regardless how it's done,sit chair on level suface while it's in clamps drying.

These chairs belong to my mother and once she leaves her house the chairs will likely go out for a yard sale or be donated. How long that might be is subject to some debate but realistically we're talking 5-7 years.

Wood flour? Are we talking the purchased stuff or can I use whatever is the dust bag of my sander? What's the ratio of glue to flour?

I'm definitely not splitting tenons. When I was into woodworking I made a small cabinet and used split tenon to attach a hand turned, cherry knob. I think it took me 3 or 4 tries to get the tenon just right.

I have a flat surface and band clamps.

Wood flower would be what ever was in the sander bag if gap joints aren't very large,tablesaw dust for larger gaps. Now that we have discussed wood flower and you say chairs have limited life expectancy,I vote for epoxy. Glad to hear you've already done split tenons,everyone needs to make them at least once so they can tell their drinking buds how easy they are.

They used to call that a fox wedge because it was in a hole.

Mike,hopfuly you found everything you need,if not just speak up,meanwhile this "fox hole" business caused me to recall another unusual name/term from long ago. Bodge or bodger that refered to chairmaking. The cabinetmaker I was pestering to alow me into his shop sent me to a guy calling himself a bodger. I think the idea was to wear out my inthusasium so that I would go away or that if I could complete a chair maybe that meant I was serious. He cut Hickory,Walnut,oak and Ash then worked it green. I must say the end product is pretty interesting. The wood srinks and swells for quite a while then slow's when wood finally cures. The chair is a little loose from the begaining but if used alot can wear and become scary loose by the time wood cures. Sound's like junk but is quite pratical for use where floor/ground is bumpy because it self level's and is almost indestructiable and wedged joints are near impossible to seperate. Of the few I've constructed,not many wanted to set on them but all sold at a premium to individuals intrigued by the novel desighn.