Googling around I see a variety of methods for cutting a fishmouth
joint.
One method is to use a cut-off wheel to make a 'V' cut, then grind to
shape.
What are they using to grind the 'V' to fit correctly? - Mike
[...]
I use WinMiter too, and it works great. After I mark the fishmouth on
the tubing with a Sharpie I use a 4.5" angle grinder to cut it out
freehand. I wear a set of heavy gloves that have saved me numerous
times.
I have a joint jigger clone that I bought years ago, but I burned up a
bunch of hole saws and never really got it to work right. I've always
wanted to try a lathe with a side mill to make precision fishmouths,
but I don't have a lathe or know how to work one.
Dave
snipped-for-privacy@evcom.net wrote in
news: snipped-for-privacy@o13g2000cwo.googlegroups.com:
Grant,
I've found Winmiter to be a treasure. I don't bother cutting the curver on
the template and tracing the edge on the tubes. I just cut a straight line
across the peaks, tape it on the tube. and grind to the line on the paper.
Well, just this morning I layed out 4 fishmouth joints on 2" pipe using one
piece of paper, which I still own. This is schedule 80 pipe, it would take a
good long time to grind to that line. I cut it out with a plasma cutter and used
a grinder by hand to clean up. Biggest gap is maybe 1/32", fine for my purposes.
I'll weld it with 6011 and then cover with 7018.
GWE
Grant Erwin wrote in
news: snipped-for-privacy@corp.supernews.com:
formatting link
.html
Another trick with Winmiter is to make a double fishmouth to join a pipe
at a right angle to the intersection of two other pipes. I did this to
make a patio-umbrella stand from 9' of 2" EMT. I cut two 3' pieces and
two 1-1/2' pieces. The two 1-1/2' sectiones were fishmouthed on one end
with the paper templates and the angle grinder. These were O-A welded,
at right angles, to the middle of one of the 3' sections, to make an
"X". This was layed flat to make the horizontal base. I needed to mount
the other 3' section vertically from the middle of the "X". This
required two fishmouths at 90 degrees from each other, because of
saddling the four intersecting legs of the base. So I printed two
templates, overlapped them on a light box (sunny window), shifted the
top one 1/4 of the template-width to the left, and traced the lines from
the bottom sheet onto the top sheet. This gave me a template for a
double-intersect(?) fishmouth.
I have "Winmiter" and "Tubemiter". Both these are freeware.
Pipe diameters can be entered into "Tubemiter" only by metric (mm)
values.
"Winmiter" allows for input in either mm or inches.
However, "Tubemiter" uniquely allows for the WALL THICKNESS of the
pipe. If "Winmiter" allows for this I'm not aware of it.
Yesterday I used "Tubemiter" for the first time to cut parts for an
anvil stand out of 2 1/2" pipe.
I printed out a template, cut it out with scissors, and wrapped it
around the pipe. I used a center punch to scribe the line in the rust
on the pipe. Put it in the chop saw mitered to 45 degrees. Cut to the
line. Changed the miter fence to a square cut. Cut of the "points" of
the cut by just "eyeballing" it.
To my surprise, each of the three fish mouths was darned close to a
perfect fit. To my even greater surprise, all of the tripod legs were
of the same length. Of course, if I'd attempted to build a FOUR legged
stand, NONE of 'em would have been even close.
The interesting thing about "Tubemiter" is that it uses the additional
parameter (wall thickness) to generate TWO curved lines. The
difference between these reminds me of the "wing tip" on "wing tip"
shoes. Apparently it represents the material that has to be removed to
get the joint to fit up.
In other words, if you were to taper the INSIDE of the pipe wall to fit
the joint, the outer wall would represent the outer line in the
template, and the inner wall would match the shape of the inner line.
I've had very little experience with either of these programs. But I
think I like "Tubemiter" a tad better.
V
Me too. Only wish it supported inches, and that you could export the image to
something useful (JPG, ...?) and that it knew about pipe & tube sizes e.g. 2"
Sch. 80 pipe. Heck, I might even be willing to pay a little for such a program.
GWE
Ok - where did you find it ?
Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder
Vern> I have "Winmiter" and "Tubemiter". Both these are freeware.
Martin,
I don't remember where I found it. But it was on the internet. Search
Google for "tubemiter". If you can't find it email me at vtuck at tucklings dot com and I'll see if I can find it again.
V
Great -
Found it ! and more naturally -
There is a text file lower down - might be useful.
formatting link
near the bottom of the page.
Tubemiter.exe by Giles Puckett (123k)
tubemit3.txt by Pucket(2k) *.html format (4k)
The header of the page : [ forced wraping ]
Sanders, Snyder & Tetz
set of Useful bike specific TOOLS in spreadsheet format.
Webmater note: This is a very useful set of spreadsheets and represents many,
many days of work by the authors.
We are supplying a set of spreadsheet tools that will give a user the ability to
quantify bicycle related issues such as determining your own power capabilities,
power vs speed, power to climb hills, CdA (aerodynamic drag), Crr (rolling
resistance),
and many more.
We have set up separate spreadsheets to reduce informational overload, and a set
of
associated descriptive texts.
We also have included instructional texts to help guide the user in making
proper measurements.
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder
Vern> Martin,
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