|
Hello again chaps,
Last question for a long time I hope - I’ve got the majority of techniques tested for the Edenstaal cannon - the last question on it, I hope is that it suggests to centre punch the ends (of a 6” x 1” dia aluminium rod) for a cannon barrel - but then says ‘clamp the work to the tool post, using a 3/8” drill in the headstock bore the barrel to a depth of 2 3/4”.
On the face of it, this doesn’t seem like an unreasonable ask - but after checking it looks like there’s a problem:
- I have the machinist vice attachment, and it just about has capacity for the 1” dia rod on the flats of the jaws (which I’ve heard is bad practise) -but the resultant centre line position of the clamped rod is way higher than the headstock centre.
- I also have a milling table attachment I can put on the toolpost, but that raises it up even higher!
The only thing that comes to mind, is using the strap clamps from the milling table directly in the t-nut slot on the tool slot!
Hopefully, that’s my last query - thank you all so much for the help, hopefully some output will be here shortly!
Cheers,
|
Instructions seem odd. The standard way of doing such a bore is TS drilling - but the workpiece is too long for that.
How I would do it is use the extended way bars, intended for wood turning. Clamp the workpiece in the 3-jaw, support it near the end with the steady rest. and put the TS on the extended end of the way bars for drilling.
Now, I realize this does not help you if you have neither the extended way bars or the steady rest. But those are two invaluable accessories for TS drilling on the Unimat (DB/SL).
Martin
-----Original Message-----
From: William Ayerst <willayerst@...>
To: [email protected]
Sent: Thu, Apr 23, 2020 1:35 pm
Subject: [Unimat] Clamping large dia. for centre-drilling
Hello again chaps,
Last question for a long time I hope - I’ve got the majority of techniques tested for the Edenstaal cannon - the last question on it, I hope is that it suggests to centre punch the ends (of a 6” x 1” dia aluminium rod) for a cannon barrel - but then says ‘clamp the work to the tool post, using a 3/8” drill in the headstock bore the barrel to a depth of 2 3/4”.
On the face of it, this doesn’t seem like an unreasonable ask - but after checking it looks like there’s a problem:
- I have the machinist vice attachment, and it just about has capacity for the 1” dia rod on the flats of the jaws (which I’ve heard is bad practise) -but the resultant centre line position of the clamped rod is way higher than the headstock centre.
- I also have a milling table attachment I can put on the toolpost, but that raises it up even higher!
The only thing that comes to mind, is using the strap clamps from the milling table directly in the t-nut slot on the tool slot!
Hopefully, that’s my last query - thank you all so much for the help, hopefully some output will be here shortly!
Cheers,
|
The drill is too big for the 0-? in Jacobs chuck. ? I guess they want the drill held in the 3 jaw chuck in the headstock but then the workholding arrangement is a bit of a mystery. As you have noticed you need to hold it so that the centre mark is at the lathe centre height. You also need to ensure it is horizontal and aligned with the bed bars too otherwise the hole will be on a skew. ? Or maybe use the drilling column (if you have one) and hold the work upright? ? I guess it all depends on what bits and pieces you have to hold the work… which is a question that will keep on coming up. ? Regards, Andy ?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of Martin P. via groups.io
Sent: 23 April 2020 19:12
To: [email protected]
Subject: Re: [Unimat] Clamping large dia. for centre-drilling ? Instructions seem odd. The standard way of doing such a bore is TS drilling - but the workpiece is too long for that. How I would do it is use the extended way bars, intended for wood turning. Clamp the workpiece in the 3-jaw, support it near the end with the steady rest. and put the TS on the extended end of the way bars for drilling. Now, I realize this does not help you if you have neither the extended way bars or the steady rest. But those are two invaluable accessories for TS drilling on the Unimat (DB/SL). -----Original Message-----
From: William Ayerst <willayerst@...>
To: [email protected]
Sent: Thu, Apr 23, 2020 1:35 pm
Subject: [Unimat] Clamping large dia. for centre-drilling Hello again chaps,
Last question for a long time I hope - I’ve got the majority of techniques tested for the Edenstaal cannon - the last question on it, I hope is that it suggests to centre punch the ends (of a 6” x 1” dia aluminium rod) for a cannon barrel - but then says ‘clamp the work to the tool post, using a 3/8” drill in the headstock bore the barrel to a depth of 2 3/4”.
On the face of it, this doesn’t seem like an unreasonable ask - but after checking it looks like there’s a problem:
- I have the machinist vice attachment, and it just about has capacity for the 1” dia rod on the flats of the jaws (which I’ve heard is bad practise) -but the resultant centre line position of the clamped rod is way higher than the headstock centre.
- I also have a milling table attachment I can put on the toolpost, but that raises it up even higher!
The only thing that comes to mind, is using the strap clamps from the milling table directly in the t-nut slot on the tool slot!
Hopefully, that’s my last query - thank you all so much for the help, hopefully some output will be here shortly!
Cheers,
|
|
|
I think the best way is to drill a?smaller hole?and then bore it to size.
-Guy-
On April 23, 2020 at 5:38 PM Andy Carlson <andycarlson@...> wrote:
The drill is too big for the 0-? in Jacobs chuck. ? I guess they want the drill held in the 3 jaw chuck in the headstock but then the workholding arrangement is a bit of a mystery. As you have noticed you need to hold it so that the centre mark is at the lathe centre height. You also need to ensure it is horizontal and aligned with the bed bars too otherwise the hole will be on a skew. ? Or maybe use the drilling column (if you have one) and hold the work upright? ? I guess it all depends on what bits and pieces you have to hold the work… which is a question that will keep on coming up. ? Regards, Andy ? From: [email protected] [mailto:[email protected]] On Behalf Of Martin P. via groups.io
Sent: 23 April 2020 19:12
To: [email protected]
Subject: Re: [Unimat] Clamping large dia. for centre-drilling ? Instructions seem odd. The standard way of doing such a bore is TS drilling - but the workpiece is too long for that. How I would do it is use the extended way bars, intended for wood turning. Clamp the workpiece in the 3-jaw, support it near the end with the steady rest. and put the TS on the extended end of the way bars for drilling. Now, I realize this does not help you if you have neither the extended way bars or the steady rest. But those are two invaluable accessories for TS drilling on the Unimat (DB/SL). -----Original Message-----
From: William Ayerst <willayerst@...>
To: [email protected]
Sent: Thu, Apr 23, 2020 1:35 pm
Subject: [Unimat] Clamping large dia. for centre-drilling Hello again chaps,
Last question for a long time I hope - I’ve got the majority of techniques tested for the Edenstaal cannon - the last question on it, I hope is that it suggests to centre punch the ends (of a 6” x 1” dia aluminium rod) for a cannon barrel - but then says ‘clamp the work to the tool post, using a 3/8” drill in the headstock bore the barrel to a depth of 2 3/4”.
On the face of it, this doesn’t seem like an unreasonable ask - but after checking it looks like there’s a problem:
- I have the machinist vice attachment, and it just about has capacity for the 1” dia rod on the flats of the jaws (which I’ve heard is bad practise) -but the resultant centre line position of the clamped rod is way higher than the headstock centre.
- I also have a milling table attachment I can put on the toolpost, but that raises it up even higher!
The only thing that comes to mind, is using the strap clamps from the milling table directly in the t-nut slot on the tool slot!
Hopefully, that’s my last query - thank you all so much for the help, hopefully some output will be here shortly!
Cheers,
?
?
|
Hi
Gang:
Using
the two quills you can only drill 5cm deep. If you clamp the
stock to the cross slide you can drill the full travel of the
carriage, plus the head stock quill. So the idea is to use the
Unimat like a boring mill, tool stays stationary and the work
piece moves.
Carl.
On 4/23/2020 2:11 PM, Martin P. via
groups.io wrote:
toggle quoted message
Show quoted text
Instructions seem odd. The standard way of
doing such a bore is TS drilling - but the workpiece is too
long for that.
How I would do it is use the extended way
bars, intended for wood turning. Clamp the workpiece in the
3-jaw, support it near the end with the steady rest. and put
the TS on the extended end of the way bars for drilling.
Now, I realize this does not help you if you
have neither the extended way bars or the steady rest. But
those are two invaluable accessories for TS drilling on the
Unimat (DB/SL).
Martin
-----Original
Message-----
From: William Ayerst <willayerst@...>
To: [email protected]
Sent: Thu, Apr 23, 2020 1:35 pm
Subject: [Unimat] Clamping large dia. for centre-drilling
Hello again chaps,
Last question for a long time I hope - I’ve got the majority
of techniques tested for the Edenstaal cannon - the last
question on it, I hope is that it suggests to centre punch
the ends (of a 6” x 1” dia aluminium rod) for a cannon
barrel - but then says ‘clamp the work to the tool post,
using a 3/8” drill in the headstock bore the barrel to a
depth of 2 3/4”.
On the face of it, this doesn’t seem like an unreasonable
ask - but after checking it looks like there’s a problem:
- I have the machinist vice attachment, and it just about
has capacity for the 1” dia rod on the flats of the jaws
(which I’ve heard is bad practise) -but the resultant centre
line position of the clamped rod is way higher than the
headstock centre.
- I also have a milling table attachment I can put on the
toolpost, but that raises it up even higher!
The only thing that comes to mind, is using the strap clamps
from the milling table directly in the t-nut slot on the
tool slot!
Hopefully, that’s my last query - thank you all so much for
the help, hopefully some output will be here shortly!
Cheers,
|
Boring is a good way to make big holes on small lathes but this workpiece is 6 inches long so I would want a fixed steady and possibly also to take the tailstock off. Even then the Unimat might be short of travel because the hole needs to be quite deep too. ? Regards, Andy ?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of Guy Winton
Sent: 24 April 2020 02:32
To: [email protected]; andycarlson@...; mdupreno1@...
Subject: Re: [Unimat] Clamping large dia. for centre-drilling? I think the best way is to drill a?smaller hole?and then bore it to size. -Guy- On April 23, 2020 at 5:38 PM Andy Carlson <andycarlson@...> wrote: The drill is too big for the 0-? in Jacobs chuck. ? I guess they want the drill held in the 3 jaw chuck in the headstock but then the workholding arrangement is a bit of a mystery. As you have noticed you need to hold it so that the centre mark is at the lathe centre height. You also need to ensure it is horizontal and aligned with the bed bars too otherwise the hole will be on a skew. ? Or maybe use the drilling column (if you have one) and hold the work upright? ? I guess it all depends on what bits and pieces you have to hold the work… which is a question that will keep on coming up. ? Regards, Andy ? From: [email protected] [mailto:[email protected]] On Behalf Of Martin P. via groups.io
Sent: 23 April 2020 19:12
To: [email protected]
Subject: Re: [Unimat] Clamping large dia. for centre-drilling ? Instructions seem odd. The standard way of doing such a bore is TS drilling - but the workpiece is too long for that. How I would do it is use the extended way bars, intended for wood turning. Clamp the workpiece in the 3-jaw, support it near the end with the steady rest. and put the TS on the extended end of the way bars for drilling. Now, I realize this does not help you if you have neither the extended way bars or the steady rest. But those are two invaluable accessories for TS drilling on the Unimat (DB/SL). -----Original Message-----
From: William Ayerst <willayerst@...>
To: [email protected]
Sent: Thu, Apr 23, 2020 1:35 pm
Subject: [Unimat] Clamping large dia. for centre-drilling Hello again chaps,
Last question for a long time I hope - I’ve got the majority of techniques tested for the Edenstaal cannon - the last question on it, I hope is that it suggests to centre punch the ends (of a 6” x 1” dia aluminium rod) for a cannon barrel - but then says ‘clamp the work to the tool post, using a 3/8” drill in the headstock bore the barrel to a depth of 2 3/4”.
On the face of it, this doesn’t seem like an unreasonable ask - but after checking it looks like there’s a problem:
- I have the machinist vice attachment, and it just about has capacity for the 1” dia rod on the flats of the jaws (which I’ve heard is bad practise) -but the resultant centre line position of the clamped rod is way higher than the headstock centre.
- I also have a milling table attachment I can put on the toolpost, but that raises it up even higher!
The only thing that comes to mind, is using the strap clamps from the milling table directly in the t-nut slot on the tool slot!
Hopefully, that’s my last query - thank you all so much for the help, hopefully some output will be here shortly!
Cheers,
?
?
|
Thanks All. Andy, I have a three jaw chuck, four jaw chuck, catchplate/faceplate + dog and the vertical milling attachment. Unfortunately, no extended way bars. I do have a Proxxon mini pillar drill too, so currently i'm thinking that the best bet is to hold the piece vertically and drill the hole downwards. Luckily, this is just cosmetic work but I guess if I'm going to end up working on pieces of this length more regularly, either the extended way bars + steady, or a larger lathe, is going to be required!
Thank you!
|
You can’t have too many lathes J ? Regards, Andy ?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of William Ayerst
Sent: 24 April 2020 08:32
To: Andy Carlson <andycarlson@...>; [email protected]
Subject: Re: [Unimat] Clamping large dia. for centre-drilling ? Thanks All. Andy, I have a three jaw chuck, four jaw chuck, catchplate/faceplate + dog and the vertical milling attachment. Unfortunately, no extended way bars. I do have a Proxxon mini pillar drill too, so currently i'm thinking that the best bet is to hold the piece vertically and drill the hole downwards. Luckily, this is just cosmetic work but I guess if I'm going to end up working on pieces of this length more regularly, either the extended way bars + steady, or a larger lathe, is going to be required!
Thank you!
|
Hi
Gang:
Years
ago when I bought my Unimat, 1973, I started acquiring
tooling. The first tool everyone with a Unimat should have is
the M12x1 tap. This will allow you to make tooling to fit the
spindle. I went to the hardware store and bought a 1/4" Rigid
drill chuck and tapped it. Since I have done 3/8" and 1/2"
chucks.
Next I
had access to scrap tools from factories. So I would cut off
longer drill bits to be short enough and also turned the shank
down to 1/4". I still have the 5/8" four flute drill that
still cuts fine.
If you
search look for "Screw Machine Drills" or Stub drills. These
are about half the length of jobbers drills and are a good
fit. Why half length drill sets cost twice as much is a
mystery to me. But they are nice and I often skip center
drilling since they flex less. I first used them drilling
holes for pop rivets in the floor of my school bus. I had
broken all the jobber drills when they flexed, when the stub
drills arrived, I don't think I broke a one!
I
think setting up the Unimat and working around its limitations
is a wonderful puzzle.
Have
fun, Carl.
|
Mr. Ayerst, if it would help, I can try to drill this hole in your piece of aluminum if you send ito me.? I do not have extra aluminum stock around.?? This of course is if you are in the US, otherwise the postage is impossible.
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Hi William,
Do you have any pictures of the Extended Way Bars. I understand the principle but I would like to see a picture of the extended bars mounted on the Uni.
Thanks
Dick
|
Hi Carl,
I have a question for you. When you tapped the drill chucks to M12 x 1mm how did you ensure good concentricity (runout)?
Dick
|
On Fri, Apr 24, 2020 at 08:33 PM, OldToolmaker wrote:
Hi Carl,
I have a question for you. When you tapped the drill chucks to M12 x 1mm how did you ensure good concentricity (runout)?
Dick
When I did it I used a tailstock ram with an ER11 collet on it to drill the 11 mm hole - I suppose a drill chuck would do just as well but the sall collets give me more working space. I have a short 11 mm drill with the shank turned down that came to me as a broken drill in an assortment of drills someone else was throwing out. The M12 × 1 tap I have has a 12 mm shank, so I clamp that straight into the tailstock itself, with no chuck or collet. Finally I finish the register with a 12 mm machine reamer that also fits direct into the tailstock. As the reamer is a little worn it cuts slightly undersize, so it is a slightly tight fit on the register. (There is endless debate about whether chucks and such locate on the register or the thread. All I can say is that the tooling I make definitely locates on the 12 mm register - it has no choice. There is no clearance there, and there is in the thread, so the register wins every time.) The way to get good concentricity is to do the M12 thread and register first, then turn the job around and screw it direct onto the spindle before doing the rest. I get extremely low runout figures every time I use my various tool and collet holders.. Incidentally I have made most of the tools from 15 mm hexagonal brass bar. The hexagon gives you spanner flats to unscrew the thing, and grips really well in the three jaw chuck. The brass cuts freely so it is easy (easier) to get accuracy, and it doesn't wear enough to worry bout for the odd jobs I do. In a toolroom it would be hardened steel and ground finishes, but brass is good enough for me. Since my DB/SL went abroad I need to make up equivalent tooling for my Unimat 3. To start with I have a nice bit of 17 mm hex bar on the shelf. Keith
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Keith,
That sounds like a good method to insure close T.I.R. I have an existing 1/4” Emco drill chuck with T.I.R. issues since new back in the fifties or sixties. It is threaded 12mm x1mm and has around .005” T.I.R. runout. I also have two new old stock 1/4” Supreme key drill chucks with a Jacobs taper having an 8mm taper shanks to fit the watchmakers spindle. They both have a small amount of runout. I would have expected better TIR from this tooling but it is acceptable.
Dick
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When I got my Unimat SL it had a 3 jaw chuck and a 4 jaw chuck, not self centering. I bought a 10mm drill chuck that had a B2 I believe taper in it. I clamped the drill chuck in the 4 jaw chuck and made sure it was running true. I bored out the back to 11mm and then put the M12x1 tap in using a fixed centre in the tailstock to make sure it was aligned. I tapped the M12x1 then bored the 12mm section. It worked fine with only a small run-out. 
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On Sat, Apr 25, 2020 at 01:34 AM, OldToolmaker wrote:
Keith,
That sounds like a good method to insure close T.I.R. I have an existing 1/4” Emco drill chuck with T.I.R. issues since new back in the fifties or sixties. It is threaded 12mm x1mm and has around .005” T.I.R. runout. I also have two new old stock 1/4” Supreme key drill chucks with a Jacobs taper having an 8mm taper shanks to fit the watchmakers spindle. They both have a small amount of runout. I would have expected better TIR from this tooling but it is acceptable.
Dick
I got a precision Jacobs chuck, 4 mm capacity, aiming to bore it out to use on the DB/SL. Once I looked at it I reakised that boring it out would mean it would fall apart, or at least be seriously damaged. Then I found I was equipped for collets (the right combination of parts arrived)? so I left it alone. Once I got the ER11ram for the tailstock (GGtools), I don't think I've used a drill chuck since. ER11 goes up to 7 mm, the usual drill chuck from Rohm is 6.35 mm. Dunno where that small chuck is now. Keith
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Carl
OldToolmaker
Les Orton