Durafix, product review
Group: alt.sailing.asa
Date: Wed, May 2, 2001, 12:26pm
From: captkeywest@webtv.net
I am sure several of you have seen the guys at the boat show weldiing aluminum with a durafix rod and a propane torch. and wondered if this stuff could be handy for "in the field" and remote repairs: (ie: where there is no tig )
I bought a half pound at the miami boat show many years ago and have experimented with the stuff only a few times.
The first time I had an opportunity to try a repair "in the field" was during a busy time in the charter business. I had discovered a small crack on our boarding ladder. Not a serious crack but my first candidate for durfafix repair!
Our aluminum dive ladder was quite substaintial maybe 10' overall length, it was quite windy on deck and my first experiment was with my handy Portasol
( great tool but as it turned out not for this)
butane torch using the blowtorch tip. I just could not get the ladder hot enough to make the durfix _flow_. Like they say on Home Improvement "I needed more power" (ahrg ahrg ahrg !) end day 1
I dug around in my shed and found a generic propane bottle type torch nozzel, got a bottle of propane. And brought it to the boat The ladder was large and cumbersome and I might have been more sucessfull if I could have gotten the ladder out of the wind and into a sheltered environment but even with the propane torch I was unable to create a fix
end day 2
After the sunset trip I was able to run to scottys hardware and get a bottle of mapp (sp?) gas to experiment with . Even with Mapp gas I just could not get the components hot enough in a windy open environment to get the durafix rod to flow. ---> end experiment & took the ladder to a welding shop. :-(
******
The next experiment:
The job was replacing an engine bed n a 32 luhrs : to pull the port engine of a 32 luhrs required pulling the 200 gallon aluminum fuel tank to access the stb engine mounts of the port engine. after draining the diesel and pulling the tank I found severe pitting on one corner of the tanks bottom -but no holes... Maybe durafix could be used as filler??
no portasol this time, and in a _sheltered from the wind_ walkway, using a borrowed propane torch (not the questionable tip fom my shed) I was able to get the durafix to flow !
It filled the pitted area niceley & saved my client the hassel of transporting the large tank to a welding shop.
That was early 1999 and the tank is still in service.
1999 ... I was taking mig & tig welding classes and
learning about welding aluminum, maybe my
inexperience had foiled my first attempts with the
ladder, maybe I just was not _patient_ enough to get
the ladder hot enough and maybe I did not realize
how fast the heat quickly dissipated from the
aluminum tubing being cooled by the wind in the
unsheltered environment.
which brings us to the year 2001. Now I can weld.
I have a mig, a tig and an oxy-acetylene torch.
the aluminum transfer case on a neighbors
Harleydavidson had broken two of the mounting ears
off. creating a need for a repair similar to the one
shown of the carb here:
I used the tig to re-attach the ears, unlike the carb shown which is rather robust, the Harley transfer case flares from the thick aluminum ears to a thinner aluminum body and required care not to distort or burn through the thinner area. Once I had the ears tacked I tried to fill (and grind and fill) with the tig to build up the flare from thin to thick but each time I risked burning through the thin stuff and decided to quit while I was ahead rather than risk distorting or damaging the case
I wondered if the durafix might help build up the flare around the ears, this time I was able to use my oxy-actetelyn and was able to get it hot enough without risking burnthrough to get the durafix to flow nicely !! :-)
yes _do_ brush your repair item with a stainless brush to remove oxides, also clean the durafix of oxides as the oxides have a higher melting temperature.
There were a couple of booths at the Dania Marine Flea market selling the stuff and the guys at the booths demonstrate the stuff making it look easy ! (hey thats their job!) take a carefull look next time you see one of these demonstrations at the size of the propane torch tip they are demonstrating with --I thought it looked a size or two larger than the _"generic"_ propane torch I had first used in my ladder repair attempts.
if you have tried durafix and had less than satisfactory results keep in mind the demonstrators at the show may have used a larger propane torch tip capable of heating a spot quicker than the generic propane tip in your shed and they probably picked a (thin) material to demostrate with (cherry picked repair)
so be patient it may take _several_ minutes to heat
the workpiece enough to get the durfix to flow.
but bottom line, _yes_ the stuff works and could be
very handy should you require a repair in some
remote area should you be cruising.
but just don't buy some and toss it in your cruising
spares _ experiment with it_ !
read the whole thread
