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Rick M,
Ah! I see, Mine are different.
Move your number 3 roller to the right so it's directly over top of your number
2 and you have my situation. I feed in between number 2 and 3, and
as the material hits number 1, it starts the role. The
first part doesn't get rolled but it rolls clear to the end. That way when
I reverse the piece, what was the leading edge gets rolled also.
I didn't role my own hull. My roles were to
small to handle it and I didn't see the roles it was done on but I assume they
were like mine because it got rolled completely to both ends. I know the
roles it was done on had 12 inch diameter rollers so if there was a straight tab
it would be at least six inches long. I had the plate sheared and
delivered so I know they didn't cut off the tails either.
I thought all roles were like the set I have.
Live and learn! Dan H.
----- Original Message -----
Sent: Thursday, November 10, 2005 7:27
PM
Subject: Re: [PSUBS-MAILIST] Inner /
Outer support ribs.
DAN
then you must have a different
roller then i have used.
plate
3
_______O____________
O O
1 2
SMALL PICTURE
once the plate passes the first roller all force
on it is lost. the only way to do that is if the rollers can be adjusted for
seperation. our big power rollers dont adjust that way
rick m
----- Original Message -----
Sent: Thursday, November 10, 2005 3:39
PM
Subject: Re: [PSUBS-MAILIST] Inner /
Outer support ribs.
Rick
It is possible to role without a flat
spot. After running the material through the rolls turn it end for end
and role it through again. The flat spot is on the leading edge first
trip through the rolls. The rolls form true to the last fraction if an
inch on the trailing edge. Turning the material around finishes what
was the leading edge the first time through.
Dan H.
----- Original Message -----
Sent: Thursday, November 10, 2005
1:58 PM
Subject: Re: [PSUBS-MAILIST] Inner /
Outer support ribs.
the problem with installing support frames is
that when rolling plate the first three to four inches can not be bent .
giving you a flat spot at the weld line in the tube.the easliest way to
get around this is to pre weld the frames inner web and true up to final
size. tack the outer web in place. do not weld the tube seam
yet. Weld in lifting eyes along the inside of the hull along the seam
line and at opposing points along the hull. set the frames inplace,
and using chain hoists pull the hull into roundness against the frames.
note some triming of the hull seam may be required for final
fit.
rick
m
----- Original Message -----
Sent: Thursday, November 10, 2005
10:02 AM
Subject: RE: [PSUBS-MAILIST] Inner
/ Outer support ribs.
Myles I should tell you getting those stiffeners in was far and
away the hardest part of building Solo. It took me three months of work
to get the first ring in. But it certainly worked as a method for
stretching the hull into roundness. This is a 3/8 thick hull of only 31"
outside diameter, so not very stretchy. If I remember correctly, the out
of roundness prior to inserting the stiffeners was about half an inch
difference between maximum and minimum diameters. With stiffeners in, I
can't detect any out of roundness.
My method was as follows: Roll the ring in along the
greater diameter, then try to straighten it until normal to the hull. I
tried hydraulics and failed. I tried icing the rings and heating the
hull, but that failed too. The latter is what Phil Nuytten does, but I
presume his hull cylinders are much higher quality (rounder) than
mine. What worked for me in the end was a very long lever built to
hook onto the end of the hull cylinder, chained to 1/2" holes drilled in
the stiffener web. I built a motorized table for my mill-drill
machine, with which I could gradually reduce the diameter of the
stiffener by a few thousandths after each unsuccessful attempt. I
did this lots of times, on each iteration getting closer to
straightening the stiffener all the way. Of course, the hard one is the
first stiffener, and after that they go fast.
rgds,
Alec
Dan,
The point I never considered
was using the rings to force the hull into roundness. I can
definately see where this would be easier when putting them on the
inside as they could be pounded / hammered / tapped into place, spot
welded, and then secured when all was well. That answers another
question in that the rings are to be pre made and not welded onto the
pressure hull when building them. In that way, the roundness of
the rings could be made true before installing. As for attaching
things to the rings inside the hull, is it safe to drill 1/4" holes
for bolts or is that comprimising the integretity of the ring too much
? ...or would welding mounting brackets to the rings and then
drilling the holes be preferable ?
On the K350, does the design
just eliminate the ring where the tower is, the tower collar providing
the strength in that area ?
Thanks for making my mind up
for me Dan.
Myles.
----- Original Message -----
Sent: Wednesday, November 09,
2005 9:10 PM
Subject: Re: [PSUBS-MAILIST]
Inner / Outer support ribs.
Myles,
A K-350 has ribs spaced 12 inches
apart, and at the ends where the hull tube meets the end caps, they
are 10 inches apart leaving two inches of hull tube sticking
past the last frames to weld the end caps to.
True, the frame would be easier to
apply to the outside of the hull, for convenience of working, but
it's easier to spring the hull into better roundness when working
from the inside. No rolled tube is perfect round.
You have to work it as your installing the
framing.
Ribs on the outside give you more
places for corrosion to attack, but do increase the inside
room. Ribs on the inside cramp the space in the sub, but are a
convenient place to clamp things that you want to add later on,
without welding on the finished sub hull.
Dan H.
----- Original Message -----
Sent: Wednesday, November 09,
2005 6:11 PM
Subject: [PSUBS-MAILIST]
Inner / Outer support ribs.
I understand that support ribs offer
the same strength increase whether they are on the inside or
outside of the pressure hull. As I am planning on adding
fairing, I am also considering puting the ribs on the outside to
free up interior space. Is this a good idea ? In other
words, is it easier to install the ribs when they are on the
outside ? Are the ribs pre-made and then welded
on or built right onto the pressure hull ? I can't seem
to figure out the ribs, how they are made, and the best way to
install them. My pressure hull is of a similar
design as the K350 36" x 1/4 " x 8'. I am considering a
rib spacing of 18".
Myles.
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