The 'Trying to Make a Thread', eh ... thread!

[Rooster]

Hi folks,

Just spent the last couple of hours (got waylaid a couple of times) searching for threads about threads. Huh? I have an idea to carve a small box that basically screws shut. Even just half a turn or something. Have any of you done anything like this.

I'm open to other suggestions, of course, but as I can't find anything on this I'm even more interested to have a go.

Thanks,
Rooster.

[toycarver]

You can buy some little thread inserts. Not sure exactly what you call them. You drill a hole in your wood and it twists into the hole, it has threads inside it that receive a screw. I just bought some at a hardware store recently. They said furniture builders use them frequently.
Here is a picture, one of the insert and screw shown seperately and the other with the screw a few turns into it. Note the little insert has a slot across the top where your screwdriver fits into it.

[Rooster]

Thanks Kris,

I'm not too sure how that would work. Then I had a look back at my post and it isn't as clear as it should be. Sorry about that.

When I get a chance I'll post a model of what I mean. I'm looking to carve a small container, about 2in high and maybe 2in diameter. To open the container, I wanted to unscrew the top from the bottom, kinda like a jar of ... baby food ... or something (yes I have babies), but I would like to carve the threads.

OK, so here is a quick sketch of what I mean. Would those thread inserts be usable in this case. Maybe hinged on the other side? Like I said earlier I'm not sure how it'd work

Thanks again Kris,
Rooster.

[Goody]

I have seen something like this done by some of the turners. The purist turn threads on the lathe. Done by turning lathe spindle by hand on a machine lathe. The easy way I have seen is find a plastic botltle with a neck size of what you want. Cut it below the threads and glue it into a groove cut into the bottom of the bowl. Use forstner bit to drill the lid and glue in the cap. If the lid is deep you can drill out the back on the cap.
Goody

[toycarver]

Oh I see what you mean. Looks like Goody has some ideas for you.

[Rooster]

Thanks Goody,

I'll probably have a go at this project over the weekend if I get a chance. I have a bottle here beside me that might be the right size. I'll have to go searching for the cap. I'm going to be mad and try to carve it with threads first and, sure, we'll see what happens from there.

I'll post some pics as I go, but don't hold your breath!!!
Rooster.

[LMiller]

Another idea?

You can carve use a 'post' and then curve a 'thread' on the other end. Think of a quarter turn thread that mates over a dowel.

Presuming the top turns and bottom doesn't: the dowel (two actually, at opposite ends of the circumference) juts out the depth of the trough (thread) on the bottom piece. As you turn the top, the incline of the trough pulls the top (lid) down onto the bottom. I would suspect it could be done if you can get the inclined trough (thread) at the proper depth and alignment. This would mean two of these troughs carved with the same inclination at the same spin. Each would need to pull the lid all the way down at 90°, half down at 45°, and so on.

If it were me, I would carve it so that the lid only fit when the slot lined up on the post. So rather than turn, the lid would slide straight down over the posts. A small twist would lock it into place by making the slot intersect a horizontal slot when properly seated.

This was hard to explain. Send me a private email if you need me to sketch these ideas out and send you a diagram of what I am suggesting.

Good Luck! Be certain to post pictures when you have completed your carved box.

LMiller

[Terry Vance]

You could carve the two halves so they fit together then put a peg in the inner half and a slot the top. The slot would need to be "L" shaped. Slid top over peg, turn slightly and it should lock in place.

Good luck...

[Dull Knife]

Originally Posted by toycarver

You can buy some little thread inserts. Not sure exactly what you call them. You drill a hole in your wood and it twists into the hole, it has threads inside it that receive a screw. I just bought some at a hardware store recently. They said furniture builders use them frequently.
Here is a picture, one of the insert and screw shown seperately and the other with the screw a few turns into it. Note the little insert has a slot across the top where your screwdriver fits into it.

Or you could try using a blind nut....you drill a hole in what ever it is that you are wanting to screw in to.

The blind nut is threaded, and has several sharp points on the bottom side that will dig in to the wood to hold the threaded part in place.

I use to use blind nuts on the under side of model airplane engine mounts.

The bolts that held the engine in place go thru the engine's motor mount holes and then screwed down in to the blind nuts under the plane's engine mounts.

Clear as mud right??....but it really isn't all that complicated.