Creating a tapered hole

[Norm Dresner]

It's a small matter but one that's driving me batty. In my modeling work I usually have anywhere from 2 to 6 little "medicine cups" [the kind they use in hospitals] filled with various liquids -- custom mixed paint, glue, paint thinners, etc -- on the bench and naturally I'm constantly knocking over one or more of these almost every day.

The obvious solution would be to create a small base for them that's tip-proof. Conceptually a 1-3/4" square of something like MDF in which there's been bored a tapered hole that matches the taper of the cups would work fine -- I've already done this with a straight-sided glue bottle that was consistently in danger of tipping because the base was too narrow for the height.

Anyway, I suppose I could drill a straight hole attack it with a rasp. I could also, I guess, use my bandsaw with the table tilted. Both of these seem like brute force and I keep thinking that there has to be a more elegant way. I just measured the slope of the side of the cup and it's ~15 degrees from the vertical so I don't think there are any router bits that would help much either.

Suggestions welcome.

Norm

[Bugs]

Do you have a wood lathe? It is a simple matter to cut tapers with it, checking the fit as you go. Without a lathe I would use a coarse half round rasp to do the job. Bugs

[Charley]

I'm not sure what angle it is, but I've seen a drill bit that was designed to cut candle holes. It might do for what you want (sorry, but I don't know where I saw it).

You might also be able to modify a spade bit to the shape that you want with careful grinding of the edges to form the correct taper.

[DanG]

I don't know your skill level or your tool availability. You can accomplish what you want with a cheap paddle bit (Irwin speed bore type bit). Grind or file the taper on the sides of the drill. This works quite well for candle holders too. ______________________________ Keep the whole world singing . . . . DanG (remove the sevens) [e-mail]

[David]

How about a base made of 2 layers. the bottom layer would have an appropriatly sized hole to fit the bottom portion of the cups.

dave

[CW]

A strait hole will hold them just fine. Don't overcomplicate this.

[Greg Neill]

Why not epoxy some spare cups to a board, and then just drop (stack) your working cups into the fixed ones?

[Norm Dresner]

Alas, no. I have a radial arm saw, mini table saw, 9" band saw, bench drill press, ... but no lathe.

Norm

[Norm Dresner]

| > The obvious solution would be to create a small base for them that's | > tip-proof. Conceptually a 1-3/4" square of something like MDF in which | > there's been bored a tapered hole that matches the taper of the cups would | > work fine -- I've already done this with a straight-sided glue bottle that | > was consistently in danger of tipping because the base was too narrow for | > the height. | >

| > Anyway, I suppose I could drill a straight hole attack it with a rasp. I | > could also, I guess, use my bandsaw with the table tilted. Both of these | > seem like brute force and I keep thinking that there has to be a more | > elegant way. I just measured the slope of the side of the cup and it's ~15 | > degrees from the vertical so I don't think there are any router bits that | > would help much either. | >

| > Suggestions welcome. | | Why not epoxy some spare cups to a board, and then just drop | (stack) your working cups into the fixed ones?

That's the simplest solution of all.

Also, if I do want to get ambitious, modifying a spade bit is also a good suggestion.

Thanks Norm

[Jay Pique]

But not the most elegant! I've done just a bit of googling and haven't found what I'm (you're) looking for. They make small tapered bits for pilot holes, and I've found some larger ones made for metal, but no dedicated ww'ing bits. I've got to figure that somebody makes them. Don't chair makers need bits like these?

Probably the least expensive as well. Now I want to find the real McCoy.

JP

[Morris Dovey]

| It's a small matter but one that's driving me batty. In my | modeling work I usually have anywhere from 2 to 6 little "medicine | cups" [the kind they use in hospitals] filled with various liquids | -- custom mixed paint, glue, paint thinners, etc -- on the bench | and naturally I'm constantly knocking over one or more of these | almost every day. | | Suggestions welcome.

If the cups are tapered, I'd think you'd only need to drill a straight hole that's a bit smaller than the top of the cup.

If you're determined to have tapered holes, KBC Tools

sells tapered milling cutters in just about every taper angle you could want (I bought a 5-degree taper for routing box lid lips). I'd clamp the workpiece to the drill press table, drill a straight hole using the bottom (small) diameter, and (without loosening the clamps!) "drill" again using the tapered mill with the drill press running at its highest speed.

-- Morris Dovey DeSoto Solar DeSoto, Iowa USA

[FriscoSoxFan]

Fill spare cup with cement. Leave a threaded metal rod centered in the concrete. You could do this by putting into a scrap board and balancing over the cup. When dried, glue some sandpaper to the outside of the cup. Chuck in the DP and Sand to size.

However, I agree with the comment that you are over-thinking. A round hole should work fine.

[David]

I'll third that emotion. I offered a suggestion earlier only because the OP seemed intent on having a tapered hole for the cups. I don't think it is at all necessary.

Dave

[bent]

i love the concrete idea.

standard tapers in machine tooling, including reamers, are Morse, Browne & Sharpe, Jarno, American National Standard Machine Tapers, American National Standard Taper Pipe.

After consulting about seventeen cross-referenced tables I realized these won't help.

large = expensive anyways. You could get an entire concrete truck delivered to the country.

I've never even tried reaming wood.

what am i doing?

[bent]

This is not expert advise. If u want, take a paddle bit, and grind the angle /^\ from|^|. Then, or at the same time, grind a sharp cutting arriss on the 2 side that touch first as it rotates. Maybe 45°. If you predrill, maybe with a hole saw, then you are cutting only on the side, and do not need to retain any front cutting edge. I can't think of the cutting edge on the face, don't know if thos lips are essential.^---^

[RicodJour]

Build a tray to hold however many cups you need with a little room between each cup. The rim of the cups should be just a little higher than the top edge of the tray. Use a carpet tack, or similar, and nail the cups to the bottom of the tray, cups spaced as required. Pour plaster into the tray up to the top edge. Let set, pull carpet tacks, remove cups (no need to grease them - they'll pop out easily).

R

[JeffB]

There are 15 deg. tapered (chamfer) router bits readily available...

[lwasserm]

Well, if it was me, I believe I'd just use a forstner to drill a STRAIGHT sided hole that was large enough to keep the cup from tipping. But if you must match the taper, try a web search on how to make a wood reamer.

[bent]

I suggested (again) grinding the sides on the tapered the paddle bit. That may not do anything but squeek. If you were intent, (not that crazy) you may have to take a dremel tool, and grind a groove. Grind it on the face, parallel to the side you tapered, again on the side that first touches as the bit spins, so that the cutting chips curl around backward and break off. It has to give the leading edge of the chip encouragement to separate, or rip. It ain't rocket science. And the difference between failure and success can be very minor indeed.

[George]

I use a spade bit, which I presume is the same, modified to the standard taper taper for making the holes in candlesticks. 7/8 taper 3/4. Quick grind job and a deburr was all it took.