Re: Tiny clock hands - advice please
I see is clocks and watches?
Here a chart for the mini rotary table 36 tooth worm and cutting a 59 tooth moon phase.?
?
?
The second file is for simple indexing 3, 4 ,5 and 7 indexing drum?
?
Dave?
?
|
It is current you have to watch for and cooling?
Some will put current limiting resistor and a threamal switch.?
?
The rule of thumb on motors max 10% over voltage.
?
I have always like this lathe?
A year ago down size to but when to mini lathe and planing a DC power feed on my mini lathe it too is 12 volts .
Here the one purchased?
?
Dave?
?
This wath just putting on my mini lathe a mini rotary table and chuck.?
That table is 3" and chuck 48mm?
?
?
FYI I only this I this first post years?
I spend most the on minilathe?
On Sat, Jan 25, 2025 at 07:03 AM, phill005 wrote:
Could anyone advise what could you safely overvolt a 24V DC motor please.
?
Phill
|
Buy extra pins that size, then. You'll likely chew them up getting them out if you do it frequently.?
Bill in OKC?
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Friday, January 31, 2025 at 09:30:33 AM CST, Peter Brooks via groups.io <peter@...> wrote:
Thanks Dick, I¡¯m in the UK though¡
?
I can see a blind hole being a problem for a pin that is tapped all the way in - to fix a handwheel for instance. My purpose would be to repeatedly locate two items together accurately, the pin wouldn¡¯t be permanent, and would be sticking out, so (hopefully!) removable.
|
To add to my last comment about tapping a dowel for removal, standard dowel pins are only case hardened so they can easily be drilled and tapped.
Dick?
?
--
http://www.homemadetools.net/forum/?OFF-SET-tailstock-center-65965#post105972
?SMALL TURRET TOOL POST PLANS?
?LARGE TURRET TOOL POST PLANS
?MINI-LATHE CARRIAGE LOCK PLANS
?SMALL QC TOOL POST PLANS?
?QUICK CHANGE LATHE TURRET
?MINI LATHE COMPOUND PIVOT MODIFICATION
|
Peter, I have tapped dowels to allow them to be removed.
Dick
--
http://www.homemadetools.net/forum/?OFF-SET-tailstock-center-65965#post105972
?SMALL TURRET TOOL POST PLANS?
?LARGE TURRET TOOL POST PLANS
?MINI-LATHE CARRIAGE LOCK PLANS
?SMALL QC TOOL POST PLANS?
?QUICK CHANGE LATHE TURRET
?MINI LATHE COMPOUND PIVOT MODIFICATION
|
Many thanks everyone! ?
?
My immediate (and very temporary) use is to register the fingerboard on a classical (nylon strung) guitar before removing and re-shaping it (and the neck). I¡¯ll be adding some more ¡®dots¡¯ up the fingerboard so there are plenty of locations for a couple of taper pins.
|
Peter, ? Straight dowels will likely give you all the accuracy you need.? Since wood changes size with humidity and the seasons, one usually needs to allow for this by locking two pieces together at one point only.? Locking pieces together at multiple points can lead to one of them developing cracks across the grain.? ? Jerry F. ?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of Peter Brooks via groups.io
Sent: Friday, January 31, 2025 5:00 AM
To: phill005; [email protected]
Subject: Re: [Unimat] Taper pins? Is it possible to make blind tapered holes? The broaches I¡¯ve looked at on clockmakers sites have angular points (as you have), but I see you also have what looks like a tapered reamer¡ What would you recommend for a medium size, say 3mm or so? A size that cutters are readily available for! Apart from metal I¡¯d also like to accurately re-align pieces of wood.
|
There are two ways to use dowels for location. The traditional way is to assemble your mechanism, or whatever, and when it is right drill and dowel the joints so it can be dismantled and rebuilt to the exact same positions. If the margin for adjustment is small the dowel holes can be drilled slightly undersize and reamed after assembly. Dowels are usually made slightly oversize so they will be a tight fit in a reamed hole. The other way of using them, which I have done a lot in recent years, is to position and ream the holes accurately in the individual parts and then they act as locations during assembly. This works with modern NC machining where you can be sure the holes are positioned accurately, so you won't need to adjust the assembly - it just goes together right. When I was designing machinery for the car industry they always wanted extractable dowels, with a tapped hole in one end. These are fairly widely available, but the smallest ones only have a small thread in them so it's as well if they are not too tight in the hole, and make sure you use a high tensile screw to get them out. You can also get non-traditional dowels which are meant to be an easy fit in reamed holes, and dual tolerance ones where one end id slightly oversize and the other end is a little smaller, so it's a tight fit in one part but loose in the other. Then the assembly can come apart easily and still be reassembled accurately.
?
Taper pins would only really be used in what I described as the traditional way, with the holes drilled and reamed after assembly. This usually means that similar parts cannot be interchanged, so you will see marking, usually one, two, three, or more centre punch marks to show what goes where. Where nominally the same part is used on a series of machines they might be marked with the machine serial number so they always go back on the right one. This dates form the days when high accuracy repeatable manufacturing was a problem and everything had to be fitted on assembly - in the old sense of made to fit, resulting in each part being unique to that assembly. I have an article in The Engineer (August 1963) praising a new marking out machine that can achieve accuracies of 0.005" over several feet, but that is still marking out with a scriber. Modern DROs and NC machines can get better accuracies than that in the positioning of an actual hole. Measuring machines can also verify the results to great accuracy.
?
And on a Unimat, so long as you work within the capacity of the machine, tight tolerances are possible. It just takes a bit of practise.
?
Note that traditional (UK) inch taper pins have a 1:48 taper, while metric ones are 1:50, so possibilities of confusion there.
|
Hi Peter:
McMaster-Carr
has a excellent online catalog, and will ship overseas. I think
they would get you good rates.
Also they
sell dowel pins with tapped holes so you can pull them from
blind holes:
I think they should be available in Europe too.
Carl.
On 1/31/2025 10:30 AM, Peter Brooks via
groups.io wrote:
toggle quoted message
Show quoted text
Thanks Dick, I¡¯m in the UK though¡
?
I can see a blind hole being a problem for a pin that is
tapped all the way in - to fix a handwheel for instance. My
purpose would be to repeatedly locate two items together
accurately, the pin wouldn¡¯t be permanent, and would be sticking
out, so (hopefully!) removable.
|
Thanks Dick, I¡¯m in the UK though¡
?
I can see a blind hole being a problem for a pin that is tapped all the way in - to fix a handwheel for instance. My purpose would be to repeatedly locate two items together accurately, the pin wouldn¡¯t be permanent, and would be sticking out, so (hopefully!) removable.
|
Good call I forgot to mention that.
?
Phill
|
A blind taper pin cannot be removed.
--
http://www.homemadetools.net/forum/?OFF-SET-tailstock-center-65965#post105972
?SMALL TURRET TOOL POST PLANS?
?LARGE TURRET TOOL POST PLANS
?MINI-LATHE CARRIAGE LOCK PLANS
?SMALL QC TOOL POST PLANS?
?QUICK CHANGE LATHE TURRET
?MINI LATHE COMPOUND PIVOT MODIFICATION
|
Peter, look at MacMaster Carr for taper pin reamers and taper pins. This is a great source and they have anything.
Dick
--
http://www.homemadetools.net/forum/?OFF-SET-tailstock-center-65965#post105972
?SMALL TURRET TOOL POST PLANS?
?LARGE TURRET TOOL POST PLANS
?MINI-LATHE CARRIAGE LOCK PLANS
?SMALL QC TOOL POST PLANS?
?QUICK CHANGE LATHE TURRET
?MINI LATHE COMPOUND PIVOT MODIFICATION
|
Brilliant, thanks Phil, just what I needed.
|
Yes no problem pre-drill a hole to depth then use the reamer to depth, you might have to do a test cut in some scrap to achieve a snug fit for the pin as you don't want the pin to bottom out.
?
Have a look here here to give you an idea:
?
Phill?
|
Thanks Phil.
?
Is it possible to make blind tapered holes? The broaches I¡¯ve looked at on clockmakers sites have angular points (as you have), but I see you also have what looks like a tapered reamer¡
?
What would you recommend for a medium size, say 3mm or so? A size that cutters are readily available for!
?
Apart from metal I¡¯d also like to accurately re-align pieces of wood.
|
This is something I have been using for years on many different projects from clocks to holding small plates whilst cutting out shapes in metal, wood, plastic on a panto-graph mill they range from thick as a hair to 6mm? tapers.
?
Phill
?
|
Hi Gang:
The tapered
drift handles on spud wrenches are not quite the same. They do
align the holes enough to get a rivet or bolt in, but do not
provide the precision location a tapered pin in a hole reamed
with a tapered reamer.
Tapered pin
have a very acute angle that provide a locking feature. The
holes are hard to ream and both parts must be reamed together to
work.
The other
options are precision dowel pins, normally 0.0002" over sized in
straight reamed holes. For slightly cruder work my favorite are
roll pins in drilled holes. They are actually stronger that
hardened dowel pins.
Carl.
On 1/30/2025 4:07 PM, Davis Johnson
wrote:
toggle quoted message
Show quoted text
Steel workers who erect the skeletons of big buildings, bridges
and similar use something called a that has a tapered
spike for a handle. They use that tapered handle to lever holes
into alignment so they can get a bolt through. Same idea on a
different scale.
On 1/30/25 15:35, Elliot Nesterman
wrote:
The tapered holes for alignment pins are made by drilling and
then
reaming with watchmakers cutting broaches. You can buy them
individually
or in a set from watchmaking tool suppliers, who also sell the
tapered pins.
On 1/30/25 2:04 PM, Peter Brooks via groups.io wrote:
A recent thread had a link to the wonderful
clickspring YouTube
clockmaking videos, and I was intrigued to see him use ¡®taper
pins¡¯ to
be able to accurately realign two plates( or, presumably,
other items.
Seems like a very smart solution.
Does anyone use these? Do you drill the holes (with a taper
drill), or
use a reamer?
And any other equally smart solutions to achieve the same
thing?
(Sorry, not specifically Unimat related - but at least it¡¯s
metalwork !)
--
Elliot Nesterman
elliot@...
"The finest jewel cannot disguise a flawed character."
|
Podge or a podger spanner in UK - Australian parlance if you need an extra search term.
On Fri, 31 Jan 2025 at 8:07 am, Davis Johnson <davis@...> wrote:
Steel workers who erect the skeletons of big buildings, bridges
and similar use something called a that has a tapered spike for a handle. They use that
tapered handle to lever holes into alignment so they can get a
bolt through. Same idea on a different scale.
On 1/30/25 15:35, Elliot Nesterman
wrote:
The tapered holes for alignment pins are made by drilling and then
reaming with watchmakers cutting broaches. You can buy them
individually
or in a set from watchmaking tool suppliers, who also sell the
tapered pins.
On 1/30/25 2:04 PM, Peter Brooks via groups.io wrote:
A recent thread had a link to the wonderful
clickspring YouTube
clockmaking videos, and I was intrigued to see him use ¡®taper
pins¡¯ to
be able to accurately realign two plates( or, presumably, other
items.
Seems like a very smart solution.
Does anyone use these? Do you drill the holes (with a taper
drill), or
use a reamer?
And any other equally smart solutions to achieve the same thing?
(Sorry, not specifically Unimat related - but at least it¡¯s
metalwork !)
--
Elliot Nesterman
elliot@...
"The finest jewel cannot disguise a flawed character."
|
Thanks Davis. Yeah, I might have been guilty of using a screwdriver in a similar (if not remotely accurate) manner to get larger things ¡®more or less¡¯ aligned!
|
davesmith1800
Bill in OKC too
OldToolmaker
Carl