Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Bob Chilcoat
 
Posts: n/a
Default How to smooth and polish the inside of 3" PVC Pipe?

I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America


  #2   Report Post  
Spehro Pefhany
 
Posts: n/a
Default

On Sun, 19 Dec 2004 20:31:35 -0500, the renowned "Bob Chilcoat"
wrote:

I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.


Could you spray it with a thick layer of some kind of release
compound?


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
  #3   Report Post  
Tom Gardner
 
Posts: n/a
Default

How about giving it an "Artistic" surface in any of a billion ways. Lots of
artists here!

"Bob Chilcoat" wrote in message
...
I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I
haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside
of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably
not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America




  #4   Report Post  
Des Bromilow
 
Posts: n/a
Default

My advice would be to NOT bother polishing it, but rather look at splitting
the pipe, to make it easier to remove it.
The wax will have a LARGE surface are to adhere on, and the friction
involved in sliding the candle out would be horrific.

I would look at splitting the pipe into at least two pieces, and using hose
clamps to hold the mould together during the pour and cooling. If you're
worried about the minor ripples etc on the finished candle, you can either
dip the entire candle after cooling, or use a plane to smooth it.

The other option would be to use a strip of sheet metal (fairly thin) with
enough length to go around the candle at least 2 times. Make a roll around
something, and use the hose clamps to hold the rolled metal together. This
would make a smaller step" at the seam, and tidier mold release (just undo
the hose clapms and roll the candle out of the metal)

my 2 c

Des Bromilow

"Bob Chilcoat" wrote in message
...
I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I

haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside

of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably

not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America




  #5   Report Post  
keith bowers
 
Posts: n/a
Default

Bob Chilcoat wrote:

I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I
haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside
of this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably
not do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America


Have you tried plastic conduit; I have been told it is smoother.

You could try washing the inside of the pipe with the purple
cleaner/activator. If you could manage to apply it very evenly you MIGHT
end up with a smoother surface. One possible way would be to roll the pipe
in a section of gutter containing an inch or so of solvent.

--
Keith Bowers - Thomasville, NC


  #6   Report Post  
Bruce L. Bergman
 
Posts: n/a
Default

On Sun, 19 Dec 2004 20:31:35 -0500, "Bob Chilcoat"
wrote:

I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.


IANA Candle Making Expert, though I have done it a few times.
You're going to need some sort of a split mold to get the candle out,
it won't just push out of a length of pipe unless it's perfectly
smooth and slightly conical, and you have the release agent applied in
just the right amount...

One wild idea - Get a 3' length of 4" or 5" snap-lock galvanized
dryer vent pipe at the local Home Depot/Lowe's/BORG.

Fold a flange on the snap-lock edges so when the edges are pulled
together you have your 3" diameter round mold, it should stay close to
round with a little massaging of the metal. Then rig up two
stretchers of 1x1 wood for the seam, and a bunch of spring clamps to
hold the edges together.

A board and some sheet gasket at the bottom for the base of the
mold. A few eye-hooks and bungee cords to hold the cylinder against
the bottom. And a big pail, serving tray or steam tray to set it all
in, so if you have a big wax spill it's contained.

Thumbtack into the board to hold the bottom end of the wick, pencil
balanced across the top of the mold to hold the top end of the wick.
Heat and pour your wax, wait a few hours for cooling, then unclamp and
slide out the candle.

-- Bruce --

--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
Spamtrapped address: Remove the python and the invalid, and use a net.
  #7   Report Post  
tomcas
 
Posts: n/a
Default

Bob Chilcoat wrote:
I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America


I don't think you are going to have to worry about release. The
coefficient of thermal expansion for wax is probably higher than PVC
which will leave clearance when it cools and it should fall right out. I
would not worry about the ripple. I think you will be able to smooth it
by playing a flame or hot air gun over the outside of the candle after
it is cast. These are just hunches, I'd try a small one first, may be
3/4" PVC pipe.
  #8   Report Post  
Carl Hoffmeyer
 
Posts: n/a
Default

Hi Bob,

"Bob Chilcoat" wrote in message
...
I've been asked by our Pastor to cast a 3" x 22" "Christ Candle

.... snip ...

After you pour the wax in and let it **thoroughly** cool, run hot water on
the outside of the PVC.
Should warm up the inner surface of the PVC enough to soften the outer layer
of the wax.

Push it out.
- Carl


  #9   Report Post  
 
Posts: n/a
Default

On Sun, 19 Dec 2004 20:31:35 -0500, "Bob Chilcoat"
wrote:

I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.


Split the pipe lengthwise. Glue it back together with a piece of paper
in each of the joints. Cast the candle and re-split the pipe.

--RC

Projects expand to fill the clamps available -- plus 20 percent
  #10   Report Post  
Gary Owens
 
Posts: n/a
Default

3" stovepipe, don't clip it together, use Duct tape, couple of layers,
remove it when cool and clean up the one side, it comes in 24 in length, and
you will even have a rippled end to put in the candle holder.
My wife has done 12" candles in them, but not, 22".
gary



"Bob Chilcoat" wrote in message
...
I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I
haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside
of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably
not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America






  #11   Report Post  
Richard J Kinch
 
Posts: n/a
Default

Bob Chilcoat writes:

Any other suggestions?


Fiberglass/epoxy or Bondo on a model.
  #12   Report Post  
Gunner
 
Posts: n/a
Default

On Mon, 20 Dec 2004 01:43:04 GMT, "Des Bromilow"
wrote:

My advice would be to NOT bother polishing it, but rather look at splitting
the pipe, to make it easier to remove it.
The wax will have a LARGE surface are to adhere on, and the friction
involved in sliding the candle out would be horrific.


Ive seen this done with PVC and Cardboard. Poster board wrapped around
a PVC form, with a couple layers of corregated cardboard wrapped
around that, snugged up tight with strapping tape. After the candle
is cast, simply unwrap it. You MAY have one small mould line on it.
Period. All else will be smooth as a babys behind.

Cast the candle with it standing up on a piece of plywood with the
cardboard tube well taped to the plywood. Stick in your wick with a
weight on the bottom end, centered at the top with a bit of dowel
across the top of the form, and as the wax is poured, tap the sides of
the tube gently to get any air bubbles flowing upwards. Pour quickly
but evenly.

Spraying the inside layer with PAM or other vegitable oils will
prevent any tendency for the wax to stick to the poster board.

Gunner



"To be civilized is to restrain the ability to commit mayhem.
To be incapable of committing mayhem is not the mark of the civilized,
merely the domesticated." - Trefor Thomas
  #13   Report Post  
Karl Vorwerk
 
Posts: n/a
Default

My Mom used to make these for their church. Use a cardboard tube of the
appropriate size then peel it off when it cools. If it needed smoothing
then I used my propane torch to smooth it.
Karl


"Bob Chilcoat" wrote in message
...
I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I
haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside
of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably
not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America




  #14   Report Post  
Boris Mohar
 
Posts: n/a
Default

On Sun, 19 Dec 2004 20:31:35 -0500, "Bob Chilcoat"
wrote:

I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.


Do a test first to see if you need a split mold. Wax shrinks quite a lot
when it cools. Maybe you can finish it on a lathe?



Regards,

Boris Mohar

Got Knock? - see:
Viatrack Printed Circuit Designs http://www3.sympatico.ca/borism/
  #15   Report Post  
B.B.
 
Posts: n/a
Default

In article ,
"Bob Chilcoat" wrote:

I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.


You might be able to massage the candle out. After you cast it, lay
the pipe on the table and roll it back and forth a bit, bearing down
somewhat. If you're gentle and the candle is still slightly warm you'll
make it a little thinner, but keep it round.

--
B.B. --I am not a goat! thegoat4 at airmail dot net
http://web2.airmail.net/thegoat4/


  #16   Report Post  
Koz
 
Posts: n/a
Default

Split mold will be easier in the long run. Cool VERY slowly and keep
feeding wax to compensate for shrinkage . The outside freezes first so
they tend to shrink from the ends and can even suck a void from the top
as the core freezes up last. You want the whole thing to be at about
the crystallization temperature at about the same time which may require
warming the mold and holding the whole thing in a warm environment as it
cools. Temperature differential from the outside to the core is your enemy.

For a high gloss finish, line your mold with a sheet of mylar. This
should be available from many hobby stores. Mylar has one heck of a
smooth finish and is also self releasing. We used to use it on resin
castings and could peel it off without any release agent, leaving the
equivalent of a polished surface without the work.

Koz

Bob Chilcoat wrote:

I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America





  #17   Report Post  
Ernie Leimkuhler
 
Posts: n/a
Default

In article , Bob Chilcoat
wrote:

I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America


Split the pipe lengthwise and tape it back together.
Spray the inside with PAM cooking spray.

Pour in the wax.
Once it has set, seperate the 2 halves.
  #18   Report Post  
Bob Chilcoat
 
Posts: n/a
Default

Thanks for all the suggestions. I thought about all of them and was about
to set up a steady rest on my wood lathe, and go after the inside with
sandpaper on a stick. Then I stopped by a plumbing supplier this morning
and just scrounged a piece of 3" schedule 30 pipe, which is much smoother on
the inside. The problem I was worrying about wasn't mold release so much as
being left with the rippled surface on the finished product. This new pipe
is much smoother inside, although it's a bit thin to make a split mold out
of. I may glue a strip of the schedule 40 along one side and split it
through the strip, although I suspect that the wax will shrink enough that I
might be able to push the candle out one end with little trouble.
Unfortunately, PVC has a much larger coefficient of thermal expansion than
most metals, and may shrink too much with the wax. We'll see.

Anyway, I'll report back after I try my first candle.

Bob

--
Bob (Chief Pilot, White Knuckle Airways)

"Bob Chilcoat" wrote in message
...
I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I

haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside

of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably

not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America




  #19   Report Post  
Martin H. Eastburn
 
Posts: n/a
Default

Ernie Leimkuhler wrote:

In article , Bob Chilcoat
wrote:


I've been asked by our Pastor to cast a 3" x 22" "Christ Candle". I haven't
been able to find a candle mold this big. I have a few feet of new 3" PVC
pipe that I can make into a mold, but the inside is rippled from the
extrusion process. Any suggestions as to the best way to make the inside of
this true and smooth so that the candle can be extracted after molding?
I''ve thought of running a cylinder hone down it, but this will probably not
do exactly what I want, and will leave a grooved surface.

I've thought of buying a piece of 3" copper drain pipe, but this will be
expensive and may be unobtainable in a two-foot lenght. I don't have slip
rollers, so I can't see how I could roll a mold. Any other suggestions?

Thanks for any help or advice you can offer.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America



Split the pipe lengthwise and tape it back together.
Spray the inside with PAM cooking spray.

Pour in the wax.
Once it has set, seperate the 2 halves.

And if tape isn't strong enough, get some SS Hose clamps and firm up not to tight.
Martin

--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
How do you polish marble tile? PaPaPeng Home Repair 7 October 17th 04 12:53 PM


All times are GMT +1. The time now is 03:05 PM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"