I need to cut a large hole in sheet metal.

Have a question or want to show off your project? Post it! No Registration Necessary.  Now with pictures!

Threaded View
Need a 9" dia hole in a 20# sheet metal
surround of a boiler.

The hole must be neat and cut in situ.

Is there a gadget constructed like a compass
that when rotated often enough will cut such
a hole?

Rather like the typical rotating glass cutter
used for cutting large holes in plate glass.

Please help, Frank



Re: I need to cut a large hole in sheet metal.
Peter Jason wrote:

Quoted text here. Click to load it

Sure. It's a circle cutting attachment for a plasma cutter.

GWE

Re: I need to cut a large hole in sheet metal.
A nibbler will do the job very nicely.  Followup cleaning with a file can
make a hole that just belongs in the piece of sheet metal.

--
Why do penguins walk so  far to get to their nesting grounds?



Re: I need to cut a large hole in sheet metal.

Quoted text here. Click to load it

Careful work taking small bites with a pair of left or right cutting snips
will make a good hole of this size.
Don Young



Re: I need to cut a large hole in sheet metal.
In situ is so complex - and in this case it might be best to
just say while it is mounted on top of the boiler or in a water deep
basement or in the .....

For the case naturally - you could use trammel points or a Plasma / gas torch
circle cutter but put a carbide scribe and cut a hole like glass but all the
way through.

I surmise you have a boiler with a cover that has an 8" hole and you want to
put on a 9" header pipe or some such.

Otherwise it would be easy for most sheet metal shops in town.

Martin

Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
IHMSA and NRA Metallic Silhouette maker & member


Peter Jason wrote:
Quoted text here. Click to load it

-

Re: I need to cut a large hole in sheet metal.
On Fri, 07 Apr 2006 09:27:48 +1000, Peter Jason wrote:

Quoted text here. Click to load it

A makeshift trammel bar of wood (1 x 2" for ex.) with a tool steel cutter
should do fine with that thin guage--pivoting on a small bolt.

Or a saber saw, with a circle-cutting guide and a toothless blade, the
kind with carbide grit available at most hardware stores.

Ken Grunke


-

Re: I need to cut a large hole in sheet metal.
Thanks for all replies, I found the following
after much looking:
http://www.mk-diamond-saws.com/images/tile_hole_cutter_small.jpg

and

http://ignitiontools.com/auctionpic/CIRCLE-HOLE-CUTTER/CIRCLE-HOLE-CUTTER-1.jpg

and

http://www.trilug.org/~chilcote/images/hole-cutter-s.jpg

and

http://zenstoves.net/Supplies/CircleHoleCutter.jpg

Regards, Frank



wrote in message
Quoted text here. Click to load it



Re: I need to cut a large hole in sheet metal.
Peter Jason wrote:
Quoted text here. Click to load it

All of these tools are meant to be used in a drill press, for the
stability.  I have used a circle cutter in a hand drill, but it was a
much smaller hole (4" diam) and it was tricky.  If you do it, be very,
*very* careful.  Use the very slowest speed that you can and keep a very
tight grip on the drill.  The problem is that the bit will grab and
bind.  Depending upon how flexible the boiler surround is, it may very
well be impossible with a hand drill.

Bob

Re: I need to cut a large hole in sheet metal.
All of those will be a disaster when used on thin material and large
diameter. They are normally used in a drill press and the work securely
clamped down. When used with a portable dirll the cutting edges will dig
in and tear the metal or flip the portable drill (and user).

There is a circle cutter used by sheet metal installers that has a
tramel point on one end, and a pilot bushing on the other. To use, mark
the center, install guide, use a spiral cutter bit in an electric drill.
  Don't have a link to it.

Peter Jason wrote:
Quoted text here. Click to load it

Re: I need to cut a large hole in sheet metal.
My boiler sides and top come off fairly easily- weil-mclane gold oil
boiler.

Dave


Re: I need to cut a large hole in sheet metal.
My problem is to fix the mess left by a
long-departed builder who installed a boiler
half above a roof and half below it.  Thus
the service panel is sealed into the roof and
now I have to cut another access to service
the gas regulator.



Quoted text here. Click to load it



Re: I need to cut a large hole in sheet metal.
wrote:

Quoted text here. Click to load it

  Holy Stupid Designs, Batman!...

  Forget cutting an access hole through the sheetmetal to fix the
boiler long term, because then you'll have to deal with rain leaks...
Sounds more like it is time to rework the boiler and/or the roof so
you have proper service access.

  Stick some pictures of what you've got there now (and how you get
access to it now) in the drop-box, and people can make educated
suggestions on a proper course of action that will look good, be
fairly easy to build, and won't break the bank.  Include distance and
roofline silhouette shots so people can get the 'theme' of the
architecture.

  I have several ideas on building a little roof or housing over the
unit, but random guessing wastes time without seeing the start and end
points.

  --<< Bruce >>--

--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
We've slightly trimmed the long signature. Click to see the full one.
Re: I need to cut a large hole in sheet metal.
Why not. I'll post some photos within the
next few days.


"Bruce L. Bergman"
message
Quoted text here. Click to load it



Re: I need to cut a large hole in sheet metal.
wrote:

Quoted text here. Click to load it

  Start a new thread when you do, and announce where the pictures are.

  I deal with several condo buildings where they just have a Raypak
natural gas fired domestic hot water boiler and a storage tank just
sitting out there exposed on the building roof.  All you need to
protect from rain are the pump motors.

  If nothing else, I've got to see why they would think they need to
seal the unit half inside the roof - they are designed for outdoor
installation.

  Unless some doofus couldn't figure out how to properly fix the
section of the roof the boiler is sitting on, and found that sealing
the whole area stopped the leak...

  (For something like that, you erect an A-frame, lift the boiler an
inch or two, have the roofers redo the roofing around the pedestal
it's sitting on, and then you slide a new sheetmetal drip pan under
the boiler before you drop it back down.  Oh, and drop it on rubber
waffle pads so it doesn't wiggle a hole in the sheetmetal cap.)

     --<< Bruce >>--

--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
We've slightly trimmed the long signature. Click to see the full one.
Re: I need to cut a large hole in sheet metal. NEW POST...
Quoted text here. Click to load it


    Note that he said "announce where the pictures are", which
implied that they should *not* be posted to the newsgroup.  Just because
it is *technically* possible does not mean that it is acceptable
behavior.

    rec.crafts.metalworking is a text-only newsgroup, not a binary
one, so binaries (including images and sound files) are not acceptable
use.  Binary newsgroups may be recognized by the word "binaries" present
in the newsgroup name.

    You were supposed to upload the images to some web site like the
dropbox (http://www.metalworking.com -- visit there to read how to do
this), and then post the resulting URL here pointing to where the images
are.

Quoted text here. Click to load it

    You have my comments on the presence of the images themselves
here.  I'll leave it to others to comment on the questions associated
with the metal cutting asked here.

    Good Luck,
        DoN.
--
    (too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
We've slightly trimmed the long signature. Click to see the full one.
Re: I need to cut a large hole in sheet metal. NEW POST...

dnichols@d-and-d.com (DoN. Nichols) writes:

Quoted text here. Click to load it

It's not just a matter of etiquette-- many news servers automatically
delete binary postings in non-binary newsgroups, so a lot of us don't
even see them.

The binary newsgroups are kept separate because they take up a *huge*
amount of bandwidth and disk space, compared to the text newsgroups, and
they put a big strain on the servers (a picture is a lot more data than a
thousand words).


Re: I need to cut a large hole in sheet metal.
This tool is made to do exactly what you are doing:

http://malco.malcoproducts.com/products/shear/hc1.asp

______________________________
Keep the whole world singing . . . .
DanG  (remove the sevens)
snipped-for-privacy@7cox.net



Quoted text here. Click to load it



Re: I need to cut a large hole in sheet metal.
Thank you; I will try to get hold of one.


Quoted text here. Click to load it



Re: I need to cut a large hole in sheet metal.
I found one, and have ordered it.
Thanks again.

message
Quoted text here. Click to load it



Site Timeline