Chair repair: removing silastic?

I have been asked to fix a chair for a friend. Once disassembled I noticed that the timber is very light and the mortise and tenon joins have been put together with silastic! The trouble is that to get a good join with an epoxy I need clean surfaces and the silastic has gone everywhere.

I've got the tenons cleaned up but the mortises are more of a challenge. Any ideas on the best way to go about it? If I use a chisel I just get smooth silastic sides to the mortise. I am thinking of a dowel in a drill with a bit of sandpaper wrapped around the end (in a split).

Petrol works well for removing silicone, but the chair may smell a bit dodgy for many years, acetone should do the same without the lingering smell and flamability:D!

:iagree:

Thanks guys, I'll give acetone a go. :2tsup:

Acetone won't touch it I'm afraid. You can buy silicone remover which is gellified sulphuric acid, but I can't say how that would affect glue up. How about mark cuts for new mortise sides, chisel and remove and glue appropriate thickness veneers slips to the tenon? :shrug:

Hi Groggy,
I bought some " Mostenbockers Lift Offe " Silicone Latex Caulk & Foam Sealant Remover. 125ml.
How ever I haven't got to use it yet, so I don't know how good it is. Was bought to do the Shower Base, but I was advised, that this is the Stuff. Bunny's $14 +.

Acetic acid also works. Ordinary table vinegar (4-8% Acetic) is not usually strong enough and high strength spirit vinegar at about 15% - 20% is required.
One advantage of acetic over petrol is that it washes off reasonably well.

Yuck. From what I am reading I may as well just bevel the sides of the mortises and use fox tenons.

Fancy using silastic :(

Hi Groggy,

I think you are on the right track. Had a similar problem with an old window frame. Tried sanding the stuff off, whicj I thought was OK, but when I ran my hand over the timber it still felt silicon slippery. The stuff had got into the weathered cracks, arrhhhh!!!.

Had to cut a bigger rebate to expose new uncontaminated wood.

Silastic great for gutters, but a pain for timber. :)

Let us know how you get on witht eh mechanical type fix.

Cheers
Pops

Turpentine also works. Lay chair sections on their sides with the silastic filled holes facing upwards, and fill with turps, and allow the silastic to soften. takes a while, but does S-L-O-W-L-Y disolve the problem. Another option is Paint Remover, or even Universal Lacquer Thinner

Been there,- done that:!. Had that headache:! Done a bit of Furniture Restoration work over the years.
It never ceases to amaze me what some people will use to, " Glue," a loose dowel, or rung back into the chair with. Liquid Nails, or Construction Adhesive is another favourite product many people use to re-glue chairs, tables, cupboards, etc, or you get the occasional person who uses a, " six inch nail," bashed right through the joint to try to hold things together, or occasionally the old farmer who believes that a piece of fencing wire and a pair of pliers will fix anything :U:U ( Well almost anything )

Roger

Oh, these chairs have not been previously repaired, that is how they were MADE! :doh: