Date:         Fri, 18 Apr 2008 18:21:05 -0600
Reply-To:     "Gary Lee www.vwrack.com" <gary2a@TELUS.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         "Gary Lee www.vwrack.com" <gary2a@TELUS.NET>
Subject:      re. tube bumpers
Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed

> Bending tube isn't cheaply done. Especially large diameter thin
> wall tubing
> like what we want for vanagon bumpers. You definitely need a
> mandrel bender
> which costs tens of thousands of dollars.
>

 >Check You Tube & see how Rocky Mountain Westy Does It !!

Here's the catch.  Notice the diameter of the tubing they are using,
1 1/2" od is my guess.  The OD of the tubing on the bumpers made by
the other two vendors (patterned after the original German Projektzwo
bumpers) is larger, 2" and maybe 2 1/2" OD.  It takes Much more to
bend tube as the diameter increases.  It is mostly an appearance
issue, but the tubing should be an appropriate size for the vehicle -
to look best.  Too large or too small does not look correct or in
proportion to the size and shape of the vehicle.  There is one size
of tubing which looks best on the Vanagon.  I give props to the two
vendors who offer Vanagon tube bumpers, the tube is a single piece
with a tight radius bend wrapping around the corners of the van.
This can only be achieved with a mandrel bender.  For small volumes
like what the vanagon market needs, this type of bending would be
done by an outside shop.
The bender in the mentioned video, by the way, is not capable of
making bends in tubing the way the other two do it.
Another way is to use weld elbows, but again this does not look the
best.
An important consideration is the weight of the bumpers.  It is much
easier to bend thicker tube, but it would just weigh too much. We
don't want 100 lbs hanging off the back of our vans, the original
metal bumper weighs 23 lbs. Which brings up another point about the
difference between tube and pipe.........

On one level, all a bumper is is a piece of metal stuck on the back
of the vehicle.  Anybody with a mig welder and a chopsaw can make
one, and many do so successfully.
To make a bumper like similar to what Projecktzwo offered requires
much more.

Gary Lee