Date: Sat, 13 Jan 2001 23:39:29 -0800
Reply-To: The Skylight Guy <reid@DCCNET.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: The Skylight Guy <reid@DCCNET.COM>
Organization: @Home Network
Subject: Re: Welding a bell housing????
Content-Type: text/plain; charset=us-ascii
HI Renaud:
A Bell housing can be welded. It is tricky, but there are a few things
you can do in preparation even if you don't know how to weld. Even
knowing about the process can help you ask technical questions to select
a qualified welder to do the job. I am a journeyman steel fabricator
and Registered A welder and have been heavily involved in the aluminum
marine industry for 27 years. I am currently designing to manufacture
aluminum boats to stick in the back of our beloved Westy. And you
thought I was only The Skylight Guy!
Preparation for Welding
1) The Bell Housing has to be cleanned. Free from grease, paint, salt,
grit, etc. Once the bult of the dirt is taken off by hand, the Bell
Housing should be committed to thorough cleaning. I found acetone is a
highly effective way to degrease the aluminum pores up to 1 or two thous
deep into the material.
2) Place the Bell Housing on a clean surface (pref aluminum surface)
3) The damaged area has to be prepped prior to welding
4) If these are holes, and if the material is approx 1/2 inch thick, the
holes will have to be plug welded, the holes themselves will have to be
bevelled out on either side of the material. The holes have to be
bevelled to a feathered edge to the center of the hole. The outside
surfaces of the material will then have to be deoxided. This is really
important to do. Welding oxides melt at a very high temperature, thus
taking away the heat input to the base material.
5) Deoxide by using a carbide tipped high speed die grinder. It is very
important that you do not touch the prepared area with any oily
substance, even your finger print can contaminate the weld zone. This
will lead to porosity in the weld and insure weld failure. If any
cleaning should be done with a stainless steel wire brush. The weld
needs to be within 4 hours of cleaning.
Welding procedures...
Make sure you know how to weld aluminum or you find a welder that has
certification in welding and has welded alluminum before. Ask the welder
questions regarding the following:
1) The welder should be knowledgable in non ferrous alloys and
proficient in aluminum practice and technique. S/he must be experienced.
2) The Bell Housing should be uniformally be heated up to 205 degrees F.
This can be checked with a welders heat stick. If you are using the TIG
method of welding, the filler rod should be of the same material as the
base metal. I am assuming this as an aluminum magnesium which is a high
tensile aluminum. The filler rod which is best recommended for this job
is an 60-83 grade filler material. The TiG rods should be deoxidized as
well with a stainless steal wire brush on its side...or with a 3M scotch
brite pad. If the welding lapses 4 hours, cleaning (deoxidizing the
welding zone) should be repeated. Oxides will return after 4 hours (GO
back to Welding Procedures step 1).
3)It is also recommended on a high humidity day, not to weld. It plays
havoc on welds. Also consult with your welder what his recommdation
would be. If one decides to weld all the welds at once, you may stagger
your weld pattern, complete one hole and move to the next and so on and
so forth.
4) After the welding has been completed, your Bell Housing will be hot.
You will want to cool this down at an even consistency. I find that
submerging the Bell Housing in a bath of vermiculite or sawdust- this
will assist in the cooling down of the material and stress relieving. If
stress may be a factor, you just want to relieve the material if you
have access to any vibratorial equipment- this will be a 30 hour process
(any know who has one of these handy?)
5) After the cool down of the material, check the welded area for any
type of imperfections. If any imperfections are found, go back to
Welding Preparation Step 1.
6) Remove any excess weld that will get in the way of bearing surfaces.
These surfaces should be machined down with a good straight egde. You
may want to do a more indepth inspection with using a di-penetration
which is a three part process. If I took this to a welding shop I would
insist on it. (Make sure you discuss this prior to the job!)
7) After all the welding procedures are completed and prior to hole
drilling, you may want to reattach your Bell Housing to the to bearing
surfaces and locating the Bell Housing on its correct plain. Using
tranfer punches through the existing holes of the opposite faces, your
holes then would be true to the Bell Housing. This would insure correct
hole alignment. Also consult with your local VW mechanic. Or good ol
Bently.
E-mail if you have any questions----
Trevor Reid...
--
Peace!
Trevor Reid
T H E S K Y L I G H T G U Y
est.1997
RR6 1501 Smith Road, Gibsons, B.C. zzzzzz\zzzzz_
Canada V0N 1V6 Ph 604 886-4564 |E[__][__]|[_]\\
e-mail: skylight@dccnet.com |skylight | guy||
............................................ =-(o)------(o)-==
http://www.theskylightguy.com
renaud e wrote:
>
> Hello
> My bell housing is really dammage and I have problem to center my
> transmission on my motor. I would like to know if I can weld my bell housing
> (some people told me that it was really tricky to weld this type of bell
> housing due to the composition (magnesium and aluminium) and probably I will
> never have a good result!
> The solution that I taught to resolve my problem, is to weld around the
> holes (due to corrosion, I don't have enough material to put a sleeve)and
> put sleeves! Is that a good solution?
> thank you in advance!
> _________________________________________________________________________
> Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
