I wanted to have a custom made bowrail made for the boat I was
renovating at the time but found the cost of having it made locally was to great, and the inconvenience of getting the boat to a fabrication shop was also a problem. So I decided to have a go at it myself. I should add that I have had some experience with steel
fabrication in the past but had never done any work of this type with stainless steel
tube before this.
I first began by searching the web for info and came across the following video on youtube which solved
a lot of the bending problem for me. Very useful video, many thanks to "LiveDontWatch" for making it.
Using the ideas shown in the video I made myself a similar setup (with a few modifications) which I will explain below with some of the photos I took at the time.
I made the bender out of scrap steel and wood and as you'll see in the photos the steel is a bit heavy duty but it's all I had laying around at the time. To make the large, and small, tube bending timber discs I used some scrap marine plywood
but found the pressure needed to bend the tube to be too great for the smaller disc so I later made another one out of a scrap slab of hardwood. (if you wanted to use this setup on a continual basis it would be better to make the discs from aluminium I think). I also packed the tubing with dry sand and plugged the ends before I began. I'm not really sure if the sand was needed though.
As my boat was taking up the whole of my shed space I had to set up my workbench outside with a temporary router table to make the discs. I made the discs as per the video using a router with a cove bit. After I assembled the bender apparatus I clamped it solidly to my work bench then tried it out a few times on some scrap S/S tubing before tackling a full length for the bowrail. ...See photos below-
1. These three pics shows the router bit used and my setup, a bit rough but it worked ok. I pretty much followed the youtube video to make the wooden discs.
2. Next pics show the completed bender, a special clamping block I made of hardwood to hold the tube in place (and the end plug
holding the sand in), and then trying out the bender on scrap 1" (25mm) stainless tubing. Note the different timbers used on the smaller disc with the later h/wood disc sandwiched between aluminium plates for extra strength, plywood
was to soft for this disc.
3. The next pics show the full 6 metre length of 1" s/s tube in the bender. The tube needed support at both ends. I started in the centre, this first bend being that nearest the bow. After I had the front bend formed I laid the tube on the boat deck
to mark the position of the rear bends. which can be seen in the last photo
of this set
4. The next pics show how I temporarily propped the bowrail on the boat while I worked out it's position and the length and angle of the four stuts which would be attached, with s/s bowrail fittings
5. This pic shows the completed bowrail The boat needed to be finished before I could fix the bowrail down permanently.
6. Finally here's a pic of my boat when completed before relaunch day. All up with fittings and tubing the bowrail cost me around AU$300. I was very pleased with the result of my first foray into the mysteries of bending stainless steel.
I hope this thread helps someone with similar ambitions.