On Fri, 21 Aug 2015 19:40:31 +0000 (UTC), Cydrome Leader
wrote:
Ned Simmons wrote:
On Fri, 21 Aug 2015 09:03:21 -0500, "Terry Coombs"
wrote:
My little tractor has had a mishap , it put a con rod out the side of the
motor . Motor in question is a Kohler KT17 opposed twin . Since these are
rather hard - and expensive - to replace , I would like to repair the hole
by welding a patch over it . This unit is over 30 years old and oil soaked
,,, I've had reasonable success a couple of times , but nothing I'd write
home about , and I'm pretty sure the reason is I haven't been getting all
the oil out of the pores .
How long and at what temp do I need to bake this thing to be reasonably
sure I've got most of the oil out ? It will be degreased with solvent first
followed by a thorough scrubbing with detergent before baking . The part
looks to be die cast , which I believe means it has a fair percentage of
silicon in the alloy , which rod is recommended ? I have on hand 4043 and
5356 , but can get other if needed .
Or do I just need to bite the bullet and drop 130 bucks on a replacement ?
There is one on fleabay right now ... it's not that I don't have the money ,
I just hate to replace something that I can repair .
If the patch is 6061 then you definitely want to use 4043 wire. When I
repaired the cast door on my lathe I knew 4043 was the rod of choice
for the combination of 6061 and cast, but when I tried the 5356 that
was on hand I couldn't get it to work without cracking.
Back in the bad old days building marine hardware, 4043 was the rod of
choice and I don't recall ever having a problem welding the odd
casting.
I doubt you'll ever get the casting clean enough to avoid black smut
around the weld, but as long as it just needs to be reasonable
oil-tight and isn't highly stressed, you should be fine.
The inside & outside of the lathe door. I suspect someone tried to
pick up the end with a fork truck without paying attention to the
door. The patched-in pieces are a mix of original fragments and new
6061 material.
http://www.nedsim.com/news/DSCN0437.JPG
http://www.nedsim.com/Monarch61Rebui...arch61_16.html
How old is that lathe? It has an interesting look How toxic was the paint
you used?
The nameplate says 1951. It seems like it was a transitional machine
between pre-carbide and more modern high-horsepower lathes. Earlier
Monarchs of similar size topped out around 500 RPM, later machines
typically had 20 HP and larger motors. Mine has a 7.5 HP motor and a
top speed around 1000 RPM.
The solvents in the Rustoleum epoxy aren't too nasty, and dissipate
pretty quickly. Mainly xylene, I think. The mist when spraying is
irritating to breath, even outdoors, but a good dust mask seems to
take care of that. I'm sure it'd be much worse for someone who's been
sensitized to epoxies. It's downright benign compared to urethanes
like Imron, which I won't go near.
--
Ned Simmons