# Truly Sliding Sliding Dovetails



## GerardW (May 30, 2013)

So I am doing some prototyping for christmas gifts this year. The plan is to have a wall mounted bottle opener with a cap-catch. Ultimately there will be beveled edges and routed profiles on nice finished hardwood and all that stuff, but for now I am playing around with pine and plywood to get the design just so before I start producing them.

The original idea for the cap catch was to epoxy a mason jar lid into a hole in a piece of wood so that the jar can be unscrewed and removed to dump the caps. When I found out the hole saw I had fit the actual glass mason jar mouth exactly, I decided to try a different approach (see below).









The idea at this point is to epoxy the actual mason jar into the hole, and cut a sliding dovetail so that the entire assembly can be removed to dump the caps.

So far my softwood experimenting has vacillated from the too-tight to the too-loose without hitting the sweet spot of smooth sliding in while also holding the mason jar securely.

Questions:
1) Is this an unrealistic expectation of a sliding dovetail? I know its a joint that can hold mechanically sound without glue, but can it have a function like this while still being structurally sound?
2) Should/would/could I wax or smooth the dovetail joint somehow to facilitate sliding smoothly?
3) When finishing this piece, should the inside of this joint be unfinished, or with a coat of poly or oil or something? I am concerned that would make the joint fit too tightly.

Any and all thoughts are welcome. I am still in the prototyping stages as I said so if there are other ideas I'd love to hear them!


----------



## Oxidd1979 (Mar 15, 2013)

Maybe a UHMW plastic slide? One side epoxied on the part with your mason jar. The other would slide well I think.


----------



## RobynHoodridge (Jan 9, 2012)

Alternate? - french cleat?


----------



## Charlie5791 (Feb 21, 2012)

with that piece holding the mason jar in place, can you get a bottle under the opener? From here it looks like some bottles wouldn't get in there at the angle needed to engage the opener. I made one of these for a cottage we used to stay at. The cap catch was a rectangular box and the bottom was just dado'ed in so it could be slid out to empty the caps.


----------



## DS (Oct 10, 2011)

Why not forget the sliding dovetail altogether…

Add a fixed shelf wth a lipped edge underneath the mason jar.

The jar would lift right out when you need to empty it.

My 2 cents.


----------



## bondogaposis (Dec 18, 2011)

The problem with sliding dovetails is that w/ changes in humidity they will either, bind up or be too loose, even if they start out just right in your shop. The answer is to make a tapered sliding dovetail as they will self adjust to the prevailing conditions and yes waxing them is a good idea.


----------



## Loren (May 30, 2008)

Consider a keyhole router bit slot. You can machine the wood to
slide into the slot, or use screws… or just make the keyhole the
standard way and use screws to fit in it.


----------



## GerardW (May 30, 2013)

Thanks for all the suggestions! I am probably making half a dozen or so of these, and I am starting to wonder if I could use different methods for attaching the catch-cap as everyone here has described. Initially my plan was to have the physical design the same, but the species of wood and finishing (router profiles, etc) different for each. Ultimately it comes down to an issue of expediency… I don't know if I have the time or wherewithal to trial-and-error a bunch of different designs…

Charlie- a good question. I tested this set up (hence the clamps) using some standard size beer bottles and didn't have a problem. The bottle opener hardware starts up much higher than I expected- with the bottle almost horizontal to get a bite.


----------



## Loren (May 30, 2008)

You could also do a half sliding dovetail with a tapered
wedge stuck in underneath.


----------



## Picklehead (Feb 12, 2013)

How about a rare earth magnet hidden in the opener that would retain the cap, or several flush-mounted where the mason jar is located.


----------



## GerardW (May 30, 2013)

Ok- next stage of prototyping. I was able to fit the lid inside the 2 3/4 hole after all! So attaching and detaching the mason jar is now possible.










I still plan to use the sliding dovetail to connect the platform, and will glue on one end only to allow for expansion. However I did notice that the tail end of my joint is a bit too tall, leaving me with a really thin gap. The joint is perfectly tight however- no rocking at all. I didn't adjust the height of my dovetail bit in the router table at all between cutting the slot and the tail. 


















Any ideas on how I can get a tighter fit? Or is this normal? I doubt it… Can't figure how the height would change when the bit height was exactly the same.


----------

