Colander Repair
Joseph Gwinn
going to replace the colander, but she has had for at least 30 years,
and likes its now uncommon wide and shallow shape. So, I must repair it.
The colander is completely made of stainless steel, the bowl being about
12" in diameter and 5" deep. Alloy unknown, but it is not magnetic.
Fabrication was a bit sloppy. Each foot is spot-welded to the bowl in
three places, at least in theory. The foot that came off instead had
one weld plus two good-intention dents, and the one weld eventually
fatigued and broke. The other two feet were each missing at least one
weld, but it was hard to tell without pulling the joint apart.
I don't have a welder, and silver brazing was going to leave a very
large and ugly heat-affected zone, which could well rust. (Not knowing
the alloy, I have to assume that it is one of those that can rust if
raised to red heat.)
So, I drilled foot and bowl to accept three stainless steel 2-56 machine
screws and nuts, with the screwheads inside the bowl. I also put one
screw apiece in the other two feet, replacing the most obvious missing
welds. The bits of screw shaft protruding from the nuts were then
peened over with a ball peen hammer to form a rough rivethead.
So far so good - it will not fail in my lifetime. But it does look a
bit crude, and the peened thread ends are a bit sharp (as I didn't form
a real rivethead), and I think real rivets would have been better.
Copper is probably too weak, ordinary steel rusts, so the rivets should
be made of stainless steel.
The question is what alloys are best for making SS rivets. This is two
questions, actually, as one may wish to cold rivet (as I did with the
2-56 screws), or hot-rivet.
Whatever alloy those SS 2-56 screws are made of certainly would work as
a rivet. These screws were intended for use on airplanes, as the
flat-head screws have 100-degree heads, so they were probably made to
some MIL-SPEC.
Googling on "stainless steel rivet" yields that lots of rivets are made
of 304 and 316 alloys, so perhaps that's the best answer, at least for
cold riveting. But then there is hot riveting, where the rivet is
heated red hot before hammering into shape.
Joe Gwinn
Bob La Londe
news:joegwinn-7335F4...@news.giganews.com...
> So, I drilled foot and bowl to accept three stainless steel 2-56 machine
> screws and nuts, with the screwheads inside the bowl. I also put one
> screw apiece in the other two feet, replacing the most obvious missing
> welds. The bits of screw shaft protruding from the nuts were then
> peened over with a ball peen hammer to form a rough rivethead.
>
> So far so good - it will not fail in my lifetime. But it does look a
> bit crude, and the peened thread ends are a bit sharp (as I didn't form
> a real rivethead), and I think real rivets would have been better.
> Copper is probably too weak, ordinary steel rusts, so the rivets should
> be made of stainless steel.
All stainless pop rivets. I get them from an outfit in Phoenix for marine
work. I've got several bags of them in various length 1/8 inch diameter
hanging from the pegboard in the shop. No clue what alloy they are. They
pop in easily enough. I suppose for "finish" work I could knock out the
stub of the stem, and then used a center punch and then pin punch to spread
and flatten the pull side.
Gunner Asch
wrote:
Just out of curiosity..other than color blend..what about Copper?
Gunner
"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.
This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." Grey Ghost
Ted Frater
Theres an old adage in applied art metalwork that says,
if you cant hide the joint, make a feature of it.
so those of us who have the blessing of a partner for more than 30 yrs,
this sort of repair job will eventually come up.
I had a similar job last year.
Her indoors, has a omlette turner? of stainless steel, the turner part
was also spot welded to the handle.
After many yrs of regular use the two seperated.
God knows how they come to break things
Probably used to open a tin lid.
She's not one to throwthings about!! in the kitchen,
Fix this for me dear was the call,
now I have tig, silver brazing alloy, etc but decided to drill out the
spot welds to 1/4in, counter sink both sides, cut a 1/4in length of
anealed copper rod insert and cold rivet over times 2.
filed flat.
also I hope, good enough for another lifetime, and no hold ups on the
omlette front.
Could have used stainless, or 70/30 brass rod but copper looks nicer,
and you can get a better feel in the rivetting.
But Thats another big subject,for another day.
Something to do with using a hammer,
Most satisfying tool.
Gunner Asch
wrote:
Indeed. And I rather like copper fitments.
cavelamb
Buerste
Send it to me and I will spotweld it.
Jim Wilkins
> "Joseph Gwinn" <joegw...@comcast.net> wrote in message
> ...
> All stainless pop rivets. I get them from an outfit in Phoenix for marine
Stanley does or did make stainless pop rivets. 1/8" dia X 1/2" long is
part # PTT48, bar code 45731 13090. The store where I found them sells
imports, closeouts and overstock so I don't know a good quick source
elsewhere.
jsw
dca...@krl.org
> Googling on "stainless steel rivet" yields that lots of rivets are made
> of 304 and 316 alloys, so perhaps that's the best answer, at least for
> cold riveting. But then there is hot riveting, where the rivet is
> heated red hot before hammering into shape.
>
> Joe Gwinn
I do not think that hot riveting would have any benefits. The length
of the shank is maybe 1/16th of an inch. Not a lot of shrinkage in
that short a length.
Dan
Denis G.
McMaster Carr has countersunk stainless steel solid rivets:
http://www.mcmaster.com/#solid-rivets/=5228i4
They might look less obvious..
Joseph Gwinn
"Bob La Londe" <nos...@nospam.no> wrote:
I didn't consider pop rivets because they yield this big sharp thing on
the blind side, and are weak relative to bolting or solid rivets. There
is actually a lot of force on these feet, given the leverage and general
banging around any kitchen implement receives.
The drive the stem out and upset with a punch approach will improve
strength and appearance but sounds like as much work as upsetting a
solid rivet, and yields something not as neat looking.
Joe Gwinn
Joseph Gwinn
wrote:
Thanks Tawm, but I have already drilled the welds out and bolted it, so
now I'm more or less committed to replacing the peened-over bolting with
rivets, which are also very common in cookware.
Joe Gwinn
Joseph Gwinn
<e81275c9-b2fc-4537...@x20g2000vbn.googlegroups.com>,
"dca...@krl.org" <dca...@krl.org> wrote:
I think you are right that these rivets are too small. I was asking
more for future reference than current need.
Joe Gwinn
Joseph Gwinn
<ef04615a-602b-4557...@m25g2000yqc.googlegroups.com>,
"Denis G." <guil...@gis.net> wrote:
I did think of this, but there is a twist. The bowl material is too
thin to countersink, but there is a standard dodge from the airplane
industry - one countersinks the piece to which the sheet will be riveted
(the foot in the present example), and dimples the (bowl) sheet to
match. But it's going to require some tooling to make those dimples in
stainless steel sheet.
This dimple-the-sheet method is the reason for 100 degree flathead
screw/rivet heads: In WW2, it was found that the aluminum sheet used
for airplane skins could be cold dimpled to 100 degrees included angle
without cracking, but 82 degrees was too severe. (Don't know about the
90 degree heads used in metric screws, but I bet that 90 degrees is also
too severe.)
Joe Gwinn
Joseph Gwinn
Gunner Asch <gun...@lightspeed.net> wrote:
The color was no issue - milady would not have cared, and copper is easy
to get and to form.
My worry is that copper is too soft and weak for such rivets to work for
long. The colander foot is fairly long compared to the space between
the welds/rivets, so the leverage is large, and I figured it would shear
off the first time the colander was dropped.
Joe Gwinn
Joseph Gwinn
Ted Frater <ted.f...@virgin.net> wrote:
> Gunner Asch wrote:
> > On Tue, 22 Dec 2009 23:15:38 -0500, Joseph Gwinn <joeg...@comcast.net>
> > wrote:
> >
> >> A few days ago, a foot broke off of my wife's favorite colander. I was
> >> going to replace the colander, but she has had for at least 30 years,
> >> and likes its now uncommon wide and shallow shape. So, I must repair it.
> >>
[snip]
> >
> >
> > Just out of curiosity..other than color blend..what about Copper?
> >
> > Gunner
> >
>
> Theres an old adage in applied art metalwork that says,
> if you cant hide the joint, make a feature of it.
> so those of us who have the blessing of a partner for more than 30 yrs,
> this sort of repair job will eventually come up.
> I had a similar job last year.
> Her indoors, has a omlette turner? of stainless steel, the turner part
> was also spot welded to the handle.
> After many yrs of regular use the two seperated.
> God knows how they come to break things
> Probably used to open a tin lid.
> She's not one to throwthings about!! in the kitchen,
> Fix this for me dear was the call,
> now I have tig, silver brazing alloy, etc but decided to drill out the
> spot welds to 1/4in, counter sink both sides, cut a 1/4in length of
> anealed copper rod insert and cold rivet over times 2.
> filed flat.
> also I hope, good enough for another lifetime, and no hold ups on the
> omlette front.
> Could have used stainless, or 70/30 brass rod but copper looks nicer,
> and you can get a better feel in the rivetting.
> But Thats another big subject,for another day.
> Something to do with using a hammer,
> Most satisfying tool.
I agree with the make-it-a-feature approach for sure.
As discussed in my answer to Gunner, I didn't think that copper was
strong enough. Nor do I have space for 1/4" rivets - the foot might be
1/2" wide. The holes I drilled are 3/32" diameter.
So, button-head or truss-head SS rivets may be the solution.
Joe Gwinn
Jim Wilkins
> In article
> <ef04615a-602b-4557-ada4-083260979...@m25g2000yqc.googlegroups.com>,
You are making a lot out of a simple task. Countersink the foot if you
like, then pound the rivet head and the bowl into it with a flat piece
of steel drilled for the rivet shank. For neatness you could pull the
shank only enough to snug it in the hole, then remove it, Flare the
end with a center punch and knock it down with a ball pein hammer.
In my experience salvaging stuff the sheet metal will deform
considerably before a stainless steel pop rivet breaks.
jsw
Jim Wilkins
> ...>
> You are making a lot out of a simple task.....
> ...
> In my experience salvaging stuff the sheet metal will deform
> considerably before a stainless steel pop rivet breaks.
>
Here is an example.
http://picasaweb.google.com/KB1DAL/Parts#5272671642404646402
The flue pipe was joined with stainless pop rivets. The circular
flange is on the end of the main section and the straight piece beyond
it, nearest the anvil, is separate. That flange took a lot of work to
make the end a light press fit into a Metalbestos chimney. I saw no
sign of cracking despite all the hammering back and forth.
As usual I found a source for commercial parts only after making my
own, so that section of flue is out in the woods under the snow with
other second-hand stainless now.
Look at the cat con heat shield photo to see how much abuse stainless
can stand. The sheet was originally the outer shell of Metalbestos
chimney and I opened up the hem and hammered it out flat without
cracking. The curved louver slots were slit with a chisel, pounded
back flat, then hammered into a groove in the edge of a disk. Crimping
pliers tapered the ends.
I've hammered other stainless steel cookware into costume armor
without breaking it. IIRC the rivets were cut from stainless steel
woodscrews.
jsw
Wild_Bill
would be if drilling holes in the legs would make them weaker.
Another option would be to solder the legs on with lead-free silver bearing
solder (tin with 5-6% silver) such as Harris Stay-Brite #8 and a flux
suitable for stainless steel (Harris Stay-clean).
The Harris #8 solder doesn't require a torch, so it won't cause discoloring
or rusting. The working temperatures are 430-530F, so it wouldn't be
suitable for cookware or utensils subjected to cooking temps.
--
WB
.........
metalworking projects
www.kwagmire.com/metal_proj.html
"Joseph Gwinn" <joeg...@comcast.net> wrote in message
news:joegwinn-7335F4...@news.giganews.com...
co_f...@yahoo.com
Well, It's too late now, but any metal fabricator that does any work
in stainless steel will have a spot welder that could have quickly
fixed your problem. The last time I had a stainless spot weld
repaired, they didn't even charge me as they had just finished a spot
welding job and the equipment was still hot and ready to go.
Paul
Denis G.
> In article
> <ef04615a-602b-4557-ada4-083260979...@m25g2000yqc.googlegroups.com>,
>
> - Show quoted text -
Maybe you can just use countersunk backing washers for the rivets.
Then you wouldn't need to worry about countersinking the colander
parts. My guess is that the stainless would take the dimpling without
tearing, but that's my WAG.
Joseph Gwinn
<b37e406e-25a1-475c...@26g2000yqo.googlegroups.com>,
"Denis G." <guil...@gis.net> wrote:
Or use a truss-head rivet for much the same effect.
> My guess is that the stainless would take the dimpling without
> tearing, but that's my WAG.
The SS will surely take the dimpling. The problem is making neat
dimples without the right equipment, and no scrap stock upon which to
experiment.
I've dimpled soft aluminum (Bud boxes) with a flat-head SS screw drawing
the sheet into a countersunk recess in an aluminum block by tightening
the nut on the SS screw. Not clear that this will work with SS, which
is far stronger.
Joe Gwinn
Joseph Gwinn
<b765c5f7-abfe-4969...@u18g2000pro.googlegroups.com>,
"pdr...@coinet.com" <co_f...@yahoo.com> wrote:
Yeah, that would have worked too. There must be many SS fabricators
around here (suburbs of Boston).
Joe Gwinn
Joseph Gwinn
"Wild_Bill" <wb_wi...@XSPAMyahoo.com> wrote:
> Rivets should make a strong reliable repair, and look good, too. My concern
> would be if drilling holes in the legs would make them weaker.
The legs are bent from a strip 7/8" wide by 3/32" thick by about 2.5"
long, so a few 3/32" or even 1/8" holes shouldn't matter.
> Another option would be to solder the legs on with lead-free silver bearing
> solder (tin with 5-6% silver) such as Harris Stay-Brite #8 and a flux
> suitable for stainless steel (Harris Stay-clean).
I thought of this, but wasn't convinced it would be strong enough. I
was also thinking of the Stay-Brite to fix the nut to the screw in lieu
of peening.
> The Harris #8 solder doesn't require a torch, so it won't cause discoloring
> or rusting. The working temperatures are 430-530F, so it wouldn't be
> suitable for cookware or utensils subjected to cooking temps.
I do have an air-acetylene (plumbers') torch, and do use it for soft
soldering. It's very fast, which actually helps keep the thermal damage
down.
I also have a 500-watt electric iron I got used for $2 and put a cord
on. Yes, half a kilowatt. I bet that'll work.
Joe Gwinn
Joseph Gwinn
<c18a2e63-1a35-454b...@n38g2000yqf.googlegroups.com>,
Jim Wilkins <kb1...@gmail.com> wrote:
Now there's an idea.
The reason to care is appearance and the elimination of sharp edges and
corners and places for rotting food to accumulate.
> In my experience salvaging stuff the sheet metal will deform
> considerably before a stainless steel pop rivet breaks.
The problem with pop rivets (and hollow rivets in general) is that they
loosen long before they pop out, because too little metal is carrying
the load. A solid rivet won't loosen, if properly sized and installed.
Joe Gwinn
Jim Wilkins
>...
> The problem with pop rivets (and hollow rivets in general) is that they
> loosen long before they pop out, because too little metal is carrying
> the load. A solid rivet won't loosen, if properly sized and installed.
>
> Joe Gwinn
True, but you have the means to retighten them, and they are much
easier to drill out without enlargening the hole. Hopefully they will
hold until you happen onto some solid rivets, probably the day after
you finish it.
I have two standards for workmanship, Unlikely to Fail for finished
products that ship, and Easy to Change for prototypes that stay in
house.
jsw
Larry Jaques
<joeg...@comcast.net> scrawled the following:
>In article
><ef04615a-602b-4557...@m25g2000yqc.googlegroups.com>,
> "Denis G." <guil...@gis.net> wrote:
>
>> McMaster Carr has countersunk stainless steel solid rivets:
>> http://www.mcmaster.com/#solid-rivets/=5228i4
>> They might look less obvious..
>
>I did think of this, but there is a twist. The bowl material is too
>thin to countersink, but there is a standard dodge from the airplane
>industry - one countersinks the piece to which the sheet will be riveted
>(the foot in the present example), and dimples the (bowl) sheet to
>match. But it's going to require some tooling to make those dimples in
>stainless steel sheet.
Excellent! Now you have a solid reason for new tools, Joe. Getchersef
a brand-spankin' new doming die/dapping punch set!
http://fwd4.me/9LD Griz $80ish
http://fwd4.me/9LJ HF $45ish ($36 local, GO FOR IT!)
http://fwd4.me/9LL eBay dapping punches, $20ish
eBay dapping block, $67ish
http://fwd4.me/9LF Amazon $46; brass, may be too soft.
>This dimple-the-sheet method is the reason for 100 degree flathead
>screw/rivet heads: In WW2, it was found that the aluminum sheet used
>for airplane skins could be cold dimpled to 100 degrees included angle
>without cracking, but 82 degrees was too severe. (Don't know about the
>90 degree heads used in metric screws, but I bet that 90 degrees is also
>too severe.)
So did heat make a difference, or was it just not doable with that
particular alum. alloy?
--
REMEMBER: The sooner you fall behind,
the more time you'll have to catch up!
Larry Jaques
<joeg...@comcast.net> scrawled the following:
>In article <3t93j5l8aib96e2gv...@4ax.com>,
Kinda like a crush bumper, it might be just the thing the colander
needs to survive yet another drop, eh? It may be worth considering
copper or aluminum rivets instead of S/S.
Buerste
<snip>
>> Send it to me and I will spotweld it.
>
> Thanks Tawm, but I have already drilled the welds out and bolted it, so
> now I'm more or less committed to replacing the peened-over bolting with
> rivets, which are also very common in cookware.
>
> Joe Gwinn
Well, you know I'd do ANYTHING for you Joe! GL!
Ted Frater
> some MIL-SPEC.
>
> Googling on "stainless steel rivet" yields that lots of rivets are made
> of 304 and 316 alloys, so perhaps that's the best answer, at least for
> cold riveting. But then there is hot riveting, where the rivet is
> heated red hot before hammering into shape.
>
> Joe Gwinn
So the collander bowl is too thin to counter sink, the feet are too
small for a larger rivet size,
the leverage on the feet is too great,
seems to me different approach is needed.
other than remaking the feet in larger stainless sheet, how about a ring
of 1/8thin stainless wire connecting the feet together.half way along
their length?
would replicate the circular collander bases other collanders have and
spread the load when in use,
ifv you havnt stainless wire then copper or brass or even galvanised
plain would do.
how you fix it to the legs depends on how the legs are formed.
We need a photo of it to devise a proper engineering solution.
Im sure NASA would have the expertise to solve this .
Joseph Gwinn
<ab136240-367f-42d3...@z41g2000yqz.googlegroups.com>,
Jim Wilkins <kb1...@gmail.com> wrote:
> On Dec 23, 2:54�pm, Joseph Gwinn <joegw...@comcast.net> wrote:
> >...
> > The problem with pop rivets (and hollow rivets in general) is that they
> > loosen long before they pop out, because too little metal is carrying
> > the load. �A solid rivet won't loosen, if properly sized and installed.
> >
> > Joe Gwinn
>
> True, but you have the means to retighten them, and they are much
> easier to drill out without enlargening the hole. Hopefully they will
> hold until you happen onto some solid rivets, probably the day after
> you finish it.
The current nut and peened-over machine screws will last until I tire of
looking at them.
> I have two standards for workmanship, Unlikely to Fail for finished
> products that ship, and Easy to Change for prototypes that stay in
> house.
Well I don't know that there is much to prototype in colanders, the
design having settled at least a century ago, and I prefer doing such
jobs at most once.
Joe Gwinn
Joseph Gwinn
The metal of the bowl and feet is soft enough that it will simply bend
if the rivets hold.
Joe Gwinn
Joseph Gwinn
Larry Jaques <novalidaddress@di\/ersify.com> wrote:
> On Wed, 23 Dec 2009 11:07:04 -0500, the infamous Joseph Gwinn
> <joeg...@comcast.net> scrawled the following:
>
> >In article
> ><ef04615a-602b-4557...@m25g2000yqc.googlegroups.com>,
> > "Denis G." <guil...@gis.net> wrote:
> >
> >> McMaster Carr has countersunk stainless steel solid rivets:
> >> http://www.mcmaster.com/#solid-rivets/=5228i4
> >> They might look less obvious..
> >
> >I did think of this, but there is a twist. The bowl material is too
> >thin to countersink, but there is a standard dodge from the airplane
> >industry - one countersinks the piece to which the sheet will be riveted
> >(the foot in the present example), and dimples the (bowl) sheet to
> >match. But it's going to require some tooling to make those dimples in
> >stainless steel sheet.
>
> Excellent! Now you have a solid reason for new tools, Joe. Getchersef
> a brand-spankin' new doming die/dapping punch set!
>
> http://fwd4.me/9LD Griz $80ish
>
> http://fwd4.me/9LJ HF $45ish ($36 local, GO FOR IT!)
>
> http://fwd4.me/9LL eBay dapping punches, $20ish
> eBay dapping block, $67ish
>
> http://fwd4.me/9LF Amazon $46; brass, may be too soft.
There's a thought - tools!
Dapping blocks and punches are not the same thing as a rivet head
forming punch. But I bet McMaster carries the correct tools.
Or, for one use, I could make the tools from soft steel.
> >This dimple-the-sheet method is the reason for 100 degree flathead
> >screw/rivet heads: In WW2, it was found that the aluminum sheet used
> >for airplane skins could be cold dimpled to 100 degrees included angle
> >without cracking, but 82 degrees was too severe. (Don't know about the
> >90 degree heads used in metric screws, but I bet that 90 degrees is also
> >too severe.)
>
> So did heat make a difference, or was it just not doable with that
> particular alum. alloy?
No, the issue was that it was too slow and too hard to heat the airplane
up, and a WW2 airplane had tens of thousands of rivets holding it
together.
Joe Gwinn
Joseph Gwinn
Ted Frater <ted.f...@virgin.net> wrote:
But then that wire ring would catch on everything. The usual
alternative is to replace the separate legs with a sheet-metal ring
shaped like a truncated cone. But this is far too much work.
I suppose I could make my own rivets from hobbyshop SS wire, which I
recall is type 304.
> We need a photo of it to devise a proper engineering solution.
It's a flat-bottomed hemisphere with three bent-strap feet spotwelded to
the flat bottom. I didn't see any catalog offerings that look exactly
like it.
> Im sure NASA would have the expertise to solve this.
Yeah - use at least four welds, so even if one weld fails the foot won't
come off.
Or the conical ring spotwelded in at least four places to the bowl -
this is a very common design, and the ring isn't going to come off so
easily.
Joe Gwinn
Joseph Gwinn
wrote:
Well, I appreciate that, but is a colander challenging enough?
Joe Gwinn
Ned Simmons
<joeg...@comcast.net> wrote:
>
>> >This dimple-the-sheet method is the reason for 100 degree flathead
>> >screw/rivet heads: In WW2, it was found that the aluminum sheet used
>> >for airplane skins could be cold dimpled to 100 degrees included angle
>> >without cracking, but 82 degrees was too severe. (Don't know about the
>> >90 degree heads used in metric screws, but I bet that 90 degrees is also
>> >too severe.)
>>
>> So did heat make a difference, or was it just not doable with that
>> particular alum. alloy?
>
>No, the issue was that it was too slow and too hard to heat the airplane
>up, and a WW2 airplane had tens of thousands of rivets holding it
>together.
>
>Joe Gwinn
There's a tool for that, of course. I'm only aware of it because I
hired a guy as a SS fabricator whose experience consisted of operating
a thermo-dimpler in the Air Force. Unfortunately that seemed to be his
only experience, and we didn't have anything that needed dimpling.
Though we were willing to train him, he just stopped showing up one
day.
http://www.tpub.com/content/aviation/14018/css/14018_531.htm
--
Ned Simmons
Joseph Gwinn
Ned Simmons <ne...@nedsim.com> wrote:
I guess the modern alloys like to be warm when dimpled. I'm pretty sure
that dimpling was done cold in WW2.
I have to wonder about someone who only learned how to operate a thermo
dimpler in the USAF, so you may have dodged a bullet.
Joe Gwinn
Larry Jaques
<joeg...@comcast.net> scrawled the following:
Um, I thought you wanted to deform the colander foot holes, forming
them for the head of the rivet. <shrug>
>Or, for one use, I could make the tools from soft steel.
"If you get the chance to buy tools, go for it!" I sez.
>> >This dimple-the-sheet method is the reason for 100 degree flathead
>> >screw/rivet heads: In WW2, it was found that the aluminum sheet used
>> >for airplane skins could be cold dimpled to 100 degrees included angle
>> >without cracking, but 82 degrees was too severe. (Don't know about the
>> >90 degree heads used in metric screws, but I bet that 90 degrees is also
>> >too severe.)
>>
>> So did heat make a difference, or was it just not doable with that
>> particular alum. alloy?
>
>No, the issue was that it was too slow and too hard to heat the airplane
>up, and a WW2 airplane had tens of thousands of rivets holding it
>together.
Yeah, that might take 3 hands.
Joseph Gwinn
Yes, but to accept flathead rivets, so that the rivet heads do not
protrude into the bowl, which requires conical dimples, not domed.
> >Or, for one use, I could make the tools from soft steel.
>
> "If you get the chance to buy tools, go for it!" I sez.
Yep. McMaster probably has them.
Joe Gwinn
Larry Jaques
<joeg...@comcast.net> scrawled the following:
So check the Griz link again. It's for -conical- dapping. Looks like
100 degree, but you wouldn't be able to use the die base with it for a
big colander.
>> >Or, for one use, I could make the tools from soft steel.
>>
>> "If you get the chance to buy tools, go for it!" I sez.
>
>Yep. McMaster probably has them.
Prolly so.
Joseph Gwinn
I know the picture makes the punches look conical, but a jewler's doming
punch always has a spherical tip, so I distrust the picture.
Joe Gwinn
Larry Jaques
<joeg...@comcast.net> scrawled the following:
>In article <vj8bj5p5vm54chuji...@4ax.com>,
<shrug> WhatEVER...