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| Gunner Asch... |
 Posted: Thu Oct 22, 2009 7:50 pm |
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Guest
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On Thu, 22 Oct 2009 14:14:06 -0700 (PDT), jw <cyberzl1 at (no spam) yahoo.com> wrote:
[quote]On Oct 22, 3:26 pm, Gunner Asch <gun... at (no spam) NOSPAMlightspeed.net> wrote:
On Thu, 22 Oct 2009 09:53:02 -0400, "Steve W." <csr... at (no spam) NOTyahoo.com
wrote:
Gunner Asch wrote:
http://picasaweb.google.com/gunnerasch/MiscStuff#5381831800188494962
This is a rotary table for a milling machine. The thingy with the wheel
on the right (small wheel with the big screw on the end...had the small
cast iron piece broken off when I got this rotory table. It needs to be
attached back to the end of the crank at the flat spot you can see just
above the screw.
Should I try to weld this? Should I mill a groove about 9/16" wide and
lay in a piece of 1/2 x 9/16 flat stock and bolt it together?
Any suggestions on the best way to secure the big piece to the little
piece?
The busted bit is engaged from the outside and puts the screw in contact
with a worm gear and the actual broken bit has an adjustment bolt for
depth and an engagement sear..so it may may be under a little stress.
The rotary table is 12" across so you can picture scale
Any suggestions/methods?
Ive got mills, cutters, 300 amp TIG, drill presses etc etc. I just need
some guidence.
Gunner
"Upon Roosevelt's death in 1945, H. L. Mencken predicted in his diary
that Roosevelt would be remembered as a great president, "maybe even
alongside Washington and Lincoln," opining that Roosevelt "had every
quality that morons esteem in their heroes.""
Being it's under stress you would probably be better off if you drilled
both pieces for a set of loose press fit steel pins. V the edges some
and weld it after the pins are in. The pins will transfer the stress
across the joint while the weld holds the parts together.
Same idea as Re-Bar in concrete.
I was originally thinking about a couple dowel pins..but the length and
size prevents me from holding the parts in a drill press or mill.
Any suggestions?
"Upon Roosevelt's death in 1945, H. L. Mencken predicted in his diary
that Roosevelt would be remembered as a great president, "maybe even
alongside Washington and Lincoln," opining that Roosevelt "had every
quality that morons esteem in their heroes.""
You've got a right angle head 
[/quote]
Ive got a Gorton Mastermill...bigger head than the Bridgeport..the head
wont fit.
[quote]
Can't clamp it to the bed of the mill somehow?
[/quote]
Gonna be hard. I can do it though.
Gunner
[quote]
JW
[/quote]
"Upon Roosevelt's death in 1945, H. L. Mencken predicted in his diary
that Roosevelt would be remembered as a great president, "maybe even
alongside Washington and Lincoln," opining that Roosevelt "had every
quality that morons esteem in their heroes."" |
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| Gunner Asch... |
| Posted: Thu Oct 22, 2009 7:52 pm |
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Guest
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On Thu, 22 Oct 2009 23:33:18 +0100, Mark Rand <randm at (no spam) internettie.co.uk>
wrote:
[quote]On Thu, 22 Oct 2009 04:24:31 -0700, Gunner Asch <gunner at (no spam) NOSPAMlightspeed.net
wrote:
Any suggestions/methods?
My personal approach would be to disassemble the thing, insert a couple of
small dowels for alignment, bevel the edges, heat both parts to 400C/750F, arc
weld using 98% nickel rods, peening the weld for each pass, then cool gently.
The presence of a foundry nearby might encourage me to glue the bits together,
plug the holes, spray several coats of high build primer/spray bondo over it
to give a shrinkage allowance. Then get the "pattern" cast and re-machine.
The reason I'd use the Ni rods is that I've got them. Anything you've got has
an advantage over anything you ain't got.
Regards
Mark Rand
RTFM
[/quote]
Ive got Ni rods as well as Ni tig material, along with silicon bronze,
phosphor bronze etc etc.
Gunner
"Upon Roosevelt's death in 1945, H. L. Mencken predicted in his diary
that Roosevelt would be remembered as a great president, "maybe even
alongside Washington and Lincoln," opining that Roosevelt "had every
quality that morons esteem in their heroes."" |
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| Bruce L. Bergman... |
| Posted: Thu Oct 22, 2009 10:20 pm |
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Guest
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On Thu, 22 Oct 2009 04:24:31 -0700, Gunner Asch
<gunner at (no spam) NOSPAMlightspeed.net> wrote:
[quote]http://picasaweb.google.com/gunnerasch/MiscStuff#5381831800188494962
This is a rotary table for a milling machine. The thingy with the wheel
on the right (small wheel with the big screw on the end...had the small
cast iron piece broken off when I got this rotory table. It needs to be
attached back to the end of the crank at the flat spot you can see just
above the screw.
Should I try to weld this? Should I mill a groove about 9/16" wide and
lay in a piece of 1/2 x 9/16 flat stock and bolt it together?
Any suggestions on the best way to secure the big piece to the little
piece?
The busted bit is engaged from the outside and puts the screw in contact
with a worm gear and the actual broken bit has an adjustment bolt for
depth and an engagement sear..so it may may be under a little stress.
The rotary table is 12" across so you can picture scale
Any suggestions/methods?
[/quote]
My first thought is to drill the center or mill two or three slots
around the perimeter on both halves, and put a dowel pin or a few HRS
keys between the pieces to hold alignment, then use standard cast iron
welding methods - preheat it in an oven or forge and weld it up with
Nickel Rod.
Disclaimer: Don't put too much weight on my observations, I've never
done anything of the sort. (Never tried stick welding, or worked on
busted CI.) I'm just looking at it as a practical excercise.
My Reasoning: You could mill a flat there and make a whole new arm
out of steel stock with that setscrew on the end - but you have also
totally trashed the piece. And that fork on the end of the busted off
chunk looks like it engages that sear for alignment and anti-rotation,
and that might be a bear to recreate.
You always need to work on the problem with "the most important tool
on your truck" before touching this with any hand or machine tools.
It's about 4 pounds, wet, wrinkly, grey and squishy soft... ;-)
Start by setting the bone and trying it again before you amputate
the whole limb and fit for a prosthesis.
If you try a simple weld job (or key/dowel and weld) and the weld
doesn't hold, you haven't screwed it up too bad and can get more
invasive when you develop and try a Plan B.
If you get invasive right off the bat, lop off the whole thing and
make a new arm, and that doesn't work, then you are well and truly
screwed.
--<< Bruce >>-- |
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| Steve W.... |
| Posted: Fri Oct 23, 2009 9:20 am |
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Guest
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Gunner Asch wrote:
[quote]On Thu, 22 Oct 2009 09:53:02 -0400, "Steve W." <csr684 at (no spam) NOTyahoo.com
wrote:
Gunner Asch wrote:
http://picasaweb.google.com/gunnerasch/MiscStuff#5381831800188494962
This is a rotary table for a milling machine. The thingy with the wheel
on the right (small wheel with the big screw on the end...had the small
cast iron piece broken off when I got this rotory table. It needs to be
attached back to the end of the crank at the flat spot you can see just
above the screw.
Should I try to weld this? Should I mill a groove about 9/16" wide and
lay in a piece of 1/2 x 9/16 flat stock and bolt it together?
Any suggestions on the best way to secure the big piece to the little
piece?
The busted bit is engaged from the outside and puts the screw in contact
with a worm gear and the actual broken bit has an adjustment bolt for
depth and an engagement sear..so it may may be under a little stress.
The rotary table is 12" across so you can picture scale
Any suggestions/methods?
Ive got mills, cutters, 300 amp TIG, drill presses etc etc. I just need
some guidence.
Gunner
"Upon Roosevelt's death in 1945, H. L. Mencken predicted in his diary
that Roosevelt would be remembered as a great president, "maybe even
alongside Washington and Lincoln," opining that Roosevelt "had every
quality that morons esteem in their heroes.""
Being it's under stress you would probably be better off if you drilled
both pieces for a set of loose press fit steel pins. V the edges some
and weld it after the pins are in. The pins will transfer the stress
across the joint while the weld holds the parts together.
Same idea as Re-Bar in concrete.
I was originally thinking about a couple dowel pins..but the length and
size prevents me from holding the parts in a drill press or mill.
Any suggestions?
[/quote]
Got a lathe? Strap it to the carriage and bore the holes horizontally.
Use a Cole drill.
--
Steve W. |
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| David Harmon... |
| Posted: Fri Oct 23, 2009 2:06 pm |
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Guest
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On Thu, 22 Oct 2009 15:05:53 -0400 in rec.crafts.metalworking, "Buerste"
<buerste at (no spam) wowway.com> wrote,
[quote]Tack it together with epoxy and get a new one cast. I KNOW that anything
else I tried would get fucked-up. I've had plenty of parts cast and it
isn't expensive.
[/quote]
What about shrink? If you use the old one for a pattern, doesn't the
new one end up the wrong size? |
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| Private... |
| Posted: Fri Oct 23, 2009 2:15 pm |
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Guest
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"Gunner Asch" <gunner at (no spam) NOSPAMlightspeed.net> wrote in message
news:l1g1e59hrp9rgjj7me8j8499jld2o7lql0 at (no spam) 4ax.com...
[quote]On Thu, 22 Oct 2009 09:04:43 -0700, "Private" <please at (no spam) dont.bother
wrote:
"Gunner Asch" <gunner at (no spam) NOSPAMlightspeed.net> wrote in message
news:grf0e5d5ib6v9eckadfci4qtqth88iku7u at (no spam) 4ax.com...
http://picasaweb.google.com/gunnerasch/MiscStuff#5381831800188494962
This is a rotary table for a milling machine. The thingy with the wheel
on the right (small wheel with the big screw on the end...had the small
cast iron piece broken off when I got this rotory table. It needs to be
attached back to the end of the crank at the flat spot you can see just
above the screw.
Should I try to weld this? Should I mill a groove about 9/16" wide and
lay in a piece of 1/2 x 9/16 flat stock and bolt it together?
Any suggestions on the best way to secure the big piece to the little
piece?
The busted bit is engaged from the outside and puts the screw in contact
with a worm gear and the actual broken bit has an adjustment bolt for
depth and an engagement sear..so it may may be under a little stress.
I suspect that the broken bit should attach to the outside radius of the
half moon shape on the main casting? There appears to be a broken surface
there, but it is so clean that it could be a failed weld or braze? It
almost looks like the remains of an unfused root between two bevels? It
is
a strange fracture? How could it have been caused?
I think someone tried adjusting the engagement screw improperly and ran
it for a period of time in stress..and it finally snapped. Its a clear,
clean sheer.
[/quote]
I am a little confused by your use of the word 'sheer'.
If I have the correct view of the original casting failure then the fracture
would not have been loaded in sheer, (I may be mistaken). If you mean that
it was a very clean and smooth fracture to have resulted from a tension
loading caused by poor or over tight adjustment, then I think I understand
and agree with you, which is why I said that the fracture seemed 'strange'
in the photo and is why I asked if it could have been a failure of an
original or repair braze or solder or glued joint. I would expect this to
be evident on the fracture face of the small piece and would certainly be
discovered when doing a test bevel cut with OA and probably also when using
a grinding disk to clean up the bevel after cutting.
I was a little surprised by the number of other posters who have proposed
various non-welding or pined and glued solutions to this problem, but now
notice that in addition to s.e.j.w. that the OP was also crossposted to
r.c.m.
Good luck, YMMV |
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| Gunner Asch... |
| Posted: Fri Oct 23, 2009 2:40 pm |
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Guest
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On Fri, 23 Oct 2009 13:15:41 -0700, "Private" <please at (no spam) dont.bother>
wrote:
[quote]
"Gunner Asch" <gunner at (no spam) NOSPAMlightspeed.net> wrote in message
news:l1g1e59hrp9rgjj7me8j8499jld2o7lql0 at (no spam) 4ax.com...
On Thu, 22 Oct 2009 09:04:43 -0700, "Private" <please at (no spam) dont.bother
wrote:
"Gunner Asch" <gunner at (no spam) NOSPAMlightspeed.net> wrote in message
news:grf0e5d5ib6v9eckadfci4qtqth88iku7u at (no spam) 4ax.com...
http://picasaweb.google.com/gunnerasch/MiscStuff#5381831800188494962
This is a rotary table for a milling machine. The thingy with the wheel
on the right (small wheel with the big screw on the end...had the small
cast iron piece broken off when I got this rotory table. It needs to be
attached back to the end of the crank at the flat spot you can see just
above the screw.
Should I try to weld this? Should I mill a groove about 9/16" wide and
lay in a piece of 1/2 x 9/16 flat stock and bolt it together?
Any suggestions on the best way to secure the big piece to the little
piece?
The busted bit is engaged from the outside and puts the screw in contact
with a worm gear and the actual broken bit has an adjustment bolt for
depth and an engagement sear..so it may may be under a little stress.
I suspect that the broken bit should attach to the outside radius of the
half moon shape on the main casting? There appears to be a broken surface
there, but it is so clean that it could be a failed weld or braze? It
almost looks like the remains of an unfused root between two bevels? It
is
a strange fracture? How could it have been caused?
I think someone tried adjusting the engagement screw improperly and ran
it for a period of time in stress..and it finally snapped. Its a clear,
clean sheer.
I am a little confused by your use of the word 'sheer'.
[/quote]
ooops..spelling checker didnt catch Shear..sorry.
[quote]
If I have the correct view of the original casting failure then the fracture
would not have been loaded in sheer, (I may be mistaken). If you mean that
it was a very clean and smooth fracture to have resulted from a tension
loading caused by poor or over tight adjustment, then I think I understand
[/quote]
Correct.
[quote]and agree with you, which is why I said that the fracture seemed 'strange'
in the photo and is why I asked if it could have been a failure of an
original or repair braze or solder or glued joint. I would expect this to
be evident on the fracture face of the small piece and would certainly be
discovered when doing a test bevel cut with OA and probably also when using
a grinding disk to clean up the bevel after cutting.
[/quote]
It..the body of the item was cast with the long piece in place.
[quote]
I was a little surprised by the number of other posters who have proposed
various non-welding or pined and glued solutions to this problem, but now
notice that in addition to s.e.j.w. that the OP was also crossposted to
r.c.m.
Good luck, YMMV
[/quote]
Thanks. It appears so far that brazing will be the method used.
Gunner
[quote]
[/quote]
"Upon Roosevelt's death in 1945, H. L. Mencken predicted in his diary
that Roosevelt would be remembered as a great president, "maybe even
alongside Washington and Lincoln," opining that Roosevelt "had every
quality that morons esteem in their heroes."" |
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| Buerste... |
| Posted: Fri Oct 23, 2009 2:56 pm |
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Guest
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"David Harmon" <source at (no spam) netcom.com> wrote in message
news:i5qdnRK-6OyekH_XnZ2dnUVZ_v6dnZ2d at (no spam) earthlink.com...
[quote]On Thu, 22 Oct 2009 15:05:53 -0400 in rec.crafts.metalworking, "Buerste"
buerste at (no spam) wowway.com> wrote,
Tack it together with epoxy and get a new one cast. I KNOW that anything
else I tried would get fucked-up. I've had plenty of parts cast and it
isn't expensive.
What about shrink? If you use the old one for a pattern, doesn't the
new one end up the wrong size?
[/quote]
Build it up with bondo where you have to machine surfaces. |
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| Private... |
| Posted: Fri Oct 23, 2009 5:23 pm |
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Guest
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"Gunner Asch" <gunner at (no spam) NOSPAMlightspeed.net> wrote in message
news:e354e59jrr73ovce01p0av3vb3vuqbahbu at (no spam) 4ax.com...
[quote]On Fri, 23 Oct 2009 13:15:41 -0700, "Private" <please at (no spam) dont.bother
snip
I am a little confused by your use of the word 'sheer'.
ooops..spelling checker didnt catch Shear..sorry.
[/quote]
My appologies also, I had not noticed the misspelling (and being a poor
speller myself, repeated it) but was only commenting on the (somewhat
confusing) use of the word shear (sheer) to indicate a very smooth fracture.
snip
[quote]It..the body of the item was cast with the long piece in place.
Thanks. It appears so far that brazing will be the method used.
[/quote]
Repair of cast is an inexact science because of the difficulty of
determining exactly what kind of cast we are working with and there are many
ranges of quality. Real cast iron was often used for making machine tools
due to its rigidity and ease of machining and it was usually the cheapest,
especially for limited production quantities. Modern high quality heavy
machinery is far more likely to be cast steel, but smaller (especially
offshore China, India, Malaysia) and especially cheaper stuff is a real
guessing game. One good indicator is that it is usually the poor quality
stuff that needs repair (YMMV). IMHO, The OA cutability test is your best
friend. Some people like the spark test but I have not learned to do this
reliably.
I have learned not to be too hasty to jump to brazing to repair cast metal
(iron or steel) because once you add brass to the area it is hard to go back
to steel. I have often repaired cast steel using xx18 and have had very
good results from steel electrodes (trade name ferroweld?)designed for
(nonmachinable) repair of cast iron. (Small welds, controlled heat input
and piening are big factors in success.) I am not a big fan of any of the
Ni rod family as they are very expensive, hard to weld and I have had mostly
poor results with them. I will use them if I need to drill or tap the weld
metal but in these cases I generally prefer brass.
Anytime I see broken cast I like to ask myself if it is possible to replace
the broken cast with fabricated steel even if it means welding a small piece
of steel onto a larger cast housing. (A good example of this is welding a
(domed, there is a trick to this) piece of thin plate into a large engine
block holed by a thrown rod.) Nonmachinable steel stick electrodes work
quite well for joining steel to cast and are stronger than brass.
I generally prefer brazing (IIRC brass has a higher tensile strength than
cast iron) for repair of smaller cast pieces and have had good luck with
this when I was able to take the time to do careful and complete prep work
and to control the pre and post heat and welding temperatures carefully.
Use an old BBQ or make a small custom oven with firebrick and old fibreglass
insulation if you can. Some use a barrel of vermiculite and bury the repair
for slow cooldown but IMHO this creates its own health concerns.
I think you are doing the right thing by doing lots of research and thinking
before rushing into this repair. It looks like a quality tool that deserves
careful work.
Good luck, YMMV |
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| Peter Fairbrother... |
| Posted: Sat Oct 24, 2009 1:59 am |
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Guest
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Gunner Asch wrote:
[quote]http://picasaweb.google.com/gunnerasch/MiscStuff#5381831800188494962
This is a rotary table for a milling machine. The thingy with the wheel
on the right (small wheel with the big screw on the end...had the small
cast iron piece broken off when I got this rotory table. It needs to be
attached back to the end of the crank at the flat spot you can see just
above the screw.
Should I try to weld this? Should I mill a groove about 9/16" wide and
lay in a piece of 1/2 x 9/16 flat stock and bolt it together?
Any suggestions on the best way to secure the big piece to the little
piece?
The busted bit is engaged from the outside and puts the screw in contact
with a worm gear and the actual broken bit has an adjustment bolt for
depth and an engagement sear..so it may may be under a little stress.
The rotary table is 12" across so you can picture scale
Any suggestions/methods?
Ive got mills, cutters, 300 amp TIG, drill presses etc etc. I just need
some guidence.
[/quote]
Looks like someone dropped the table which then landed on the handle,
which rotated the shaft and the broken bit about the pin in the big
hole, and broke off the end. Tables are b****y heavy, it's easy enough
to do.
First disassemble it fully, removing the handle and shaft. Clean
thoroughly, any oil will make most techniques fail.
I would then pin and bronze-braze it, but then I do a lot of brazing.
Use a decent hearth and a *lot* of *slow* preheat, almost to dull red,
followed by a soak at heat and a long slow cooling - but you'd need a
minimum of a big gas/air torch or possibly two for preheat, and OA or
TIG or AC/DCEN bronze stick for the brazing.
It is also possible to weld cast iron using nickel rods, but that's
really only a job for the highly experienced.
Another option is fusion welding - first tack the pieces in position.
Bodge up a furnace out of firebrick or something and fill with charcoal.
Use a blower until the part is dull red, then turn off the blower and
weld in the furnace with a CI stick. Thick gloves, that sucker will be
hot! Add more charcoal, blow some more until not quite red hot, then
cover it all with sand and leave for a day or two.
As you will have noticed, getting CI hot before welding or brazing is
important, as is post-heat. CI is quite rigid and has low tensile
strength, and heating portions to different temperatures will cause
stresses through differential expansion which CI can't handle. Evenness
of temperature is most important.
Having said that, in this case the cross-section is not very large, and
as it's a straight through break, rather than a crack, most of the
stresses will be in directions which don't matter that much, so you have
a better chance of success than for most CI repairs.
Getting somewhat bodgier now. I don't know whether a hot domestic oven
would do for preheat/cooling, but you could give it a try. If you have a
weedwhacker or a similar powerful gas torch you could try that,
especially if you can bodge up some kind of hearth to reflect the heat
back in.
I'd try DCEN stick brazing first, run fairly cold (about 2/3 normal
current) with a bronze rod, or AC stick if you don't have DCEN, rather
than TIG. Borax will do for flux if you need extra or the rod is
uncoated, and is cheap.
If you braze with brass rather than bronze it'll be harder (read:
impossible) to weld it later if it breaks again. Thoroughly brush the
prepared surfaces with a stainless brush before brazing, it helps remove
the carbon layer which may prevent the braze wetting the CI.
If you can't pin it, tack or screw the parts together with a strip of
metal to one side of the parts and braze the other side, then remove the
strip (but see below) and braze the other side, keeping it as hot as you
can all the while.
If there's room in the table you might also be able to reinforce it with
some extra weld/braze/metal stuck on the outsides, including over the
flat edge of the D which I think is where most of the tension is.
-- Peter Fairbrother |
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| Gunner Asch... |
| Posted: Sat Oct 24, 2009 5:12 am |
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Guest
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On Sat, 24 Oct 2009 08:59:35 +0100, Peter Fairbrother
<zenadsl6186 at (no spam) zen.co.uk> wrote:
[quote]Gunner Asch wrote:
http://picasaweb.google.com/gunnerasch/MiscStuff#5381831800188494962
This is a rotary table for a milling machine. The thingy with the wheel
on the right (small wheel with the big screw on the end...had the small
cast iron piece broken off when I got this rotory table. It needs to be
attached back to the end of the crank at the flat spot you can see just
above the screw.
Should I try to weld this? Should I mill a groove about 9/16" wide and
lay in a piece of 1/2 x 9/16 flat stock and bolt it together?
Any suggestions on the best way to secure the big piece to the little
piece?
The busted bit is engaged from the outside and puts the screw in contact
with a worm gear and the actual broken bit has an adjustment bolt for
depth and an engagement sear..so it may may be under a little stress.
The rotary table is 12" across so you can picture scale
Any suggestions/methods?
Ive got mills, cutters, 300 amp TIG, drill presses etc etc. I just need
some guidence.
Looks like someone dropped the table which then landed on the handle,
which rotated the shaft and the broken bit about the pin in the big
hole, and broke off the end. Tables are b****y heavy, it's easy enough
to do.
First disassemble it fully, removing the handle and shaft. Clean
thoroughly, any oil will make most techniques fail.
I would then pin and bronze-braze it, but then I do a lot of brazing.
Use a decent hearth and a *lot* of *slow* preheat, almost to dull red,
followed by a soak at heat and a long slow cooling - but you'd need a
minimum of a big gas/air torch or possibly two for preheat, and OA or
TIG or AC/DCEN bronze stick for the brazing.
It is also possible to weld cast iron using nickel rods, but that's
really only a job for the highly experienced.
Another option is fusion welding - first tack the pieces in position.
Bodge up a furnace out of firebrick or something and fill with charcoal.
Use a blower until the part is dull red, then turn off the blower and
weld in the furnace with a CI stick. Thick gloves, that sucker will be
hot! Add more charcoal, blow some more until not quite red hot, then
cover it all with sand and leave for a day or two.
As you will have noticed, getting CI hot before welding or brazing is
important, as is post-heat. CI is quite rigid and has low tensile
strength, and heating portions to different temperatures will cause
stresses through differential expansion which CI can't handle. Evenness
of temperature is most important.
Having said that, in this case the cross-section is not very large, and
as it's a straight through break, rather than a crack, most of the
stresses will be in directions which don't matter that much, so you have
a better chance of success than for most CI repairs.
Getting somewhat bodgier now. I don't know whether a hot domestic oven
would do for preheat/cooling, but you could give it a try. If you have a
weedwhacker or a similar powerful gas torch you could try that,
especially if you can bodge up some kind of hearth to reflect the heat
back in.
I'd try DCEN stick brazing first, run fairly cold (about 2/3 normal
current) with a bronze rod, or AC stick if you don't have DCEN, rather
than TIG. Borax will do for flux if you need extra or the rod is
uncoated, and is cheap.
If you braze with brass rather than bronze it'll be harder (read:
impossible) to weld it later if it breaks again. Thoroughly brush the
prepared surfaces with a stainless brush before brazing, it helps remove
the carbon layer which may prevent the braze wetting the CI.
If you can't pin it, tack or screw the parts together with a strip of
metal to one side of the parts and braze the other side, then remove the
strip (but see below) and braze the other side, keeping it as hot as you
can all the while.
If there's room in the table you might also be able to reinforce it with
some extra weld/braze/metal stuck on the outsides, including over the
flat edge of the D which I think is where most of the tension is.
-- Peter Fairbrother
[/quote]
Very good. In fact..I believe that I will mill a rectangular keyway
several inches lengthwise across both halves of the break, and drill
and tap a key inside that keyway to hold everything in positon and then
braze all around.
With a a 1/2x9/16 steel "key" inserted and screwed to both halves..it
should add strength as well as holding both halves in perfect alignment
to finish the rest of the brazing.
Any negatives?
Gunner
"Upon Roosevelt's death in 1945, H. L. Mencken predicted in his diary
that Roosevelt would be remembered as a great president, "maybe even
alongside Washington and Lincoln," opining that Roosevelt "had every
quality that morons esteem in their heroes."" |
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