Moderated Discussion Areas
ContinuousWave: Whaler Repairs/Mods
Fabricating Railing: Bending Curves
|Author||Topic: Fabricating Railing: Bending Curves|
posted 04-07-2002 12:31 AM ET (US)
I was thinking about fabricating my own rails for my Montauk console, but I am having a little difficulty determining the best way to measure for the bends themself. I think (I remember from a long while ago) that in order to compensate for a 90-degree bend, you need to add half the diameter to your bend point. Ex: if you had a console width of 30-inches, after the first 90-degree bend, you would measure 30 and then add half the diameter to that number. If the diameter were 7/8-inch, you would add 7/16-inch, thus, the measurement would be 30 and 7/16-inches. And this would then have an opening of 30 inches. Am I close? In the right church? Is there a better way to do this?
Thanks for the help.
posted 04-07-2002 09:09 AM ET (US)
Dave, the bender you use will have a formula depending on the diameter of bend. Usual adder is 1/2-D or one R, and the diameter of tubing is not in the formula if you are measuring "outside to outside" (which is how I always measure). Suggestion> get some 3/4D electrical conduit (EMT) and verify/practice. Happy Whalin'... clark.. SCN
posted 04-07-2002 10:09 AM ET (US)
When bending tubing, do you fill the tubing with packed wet sand to help prevent it from collapse and kinking?
posted 04-07-2002 11:13 AM ET (US)
With a proper pipe bending tool,you will not have the crimping problem. Practice makes perfect, so the conduit suggestion is a good one and it is relatively inexpensive.
Jim-I never used sand, but sounds interesting. I have bent a lot of copper in a "this old house project," however.
posted 04-07-2002 12:01 PM ET (US)
Remember guys - the electrical conduit is somewhat softer than stainless steel - hence the two will bend differently - the conduit will crimp easier. Indeed, using packed wet sand, as JimH suggested is the only (?) way to go. Use a pipe bender tool as used by plumbers and electricians to make your bends and as someone suggested - practice on the same diamter conduit. ---- Jerry/Idaho
posted 04-07-2002 01:55 PM ET (US)
Northern Catalog has a hydraulic pipe bender for about $90 with different size dies included. Has anyone tried this? Dave
posted 04-07-2002 03:05 PM ET (US)
I've used a 1/2" tubing bender for EMT, electric metallic conduit AKA thinwall. It's not hard. The trick is making sure that the bends are the correct distance and angle relative to each other. Remember, you can't unbend it.
Didn't the shipshape tv show have a segment on fabricating a bow rail?
I'm not near the boat but I think the radius on the montauk console rails may be different than standard radii for EMT. Standard radius for 1/2 inch EMT 5", for 3/4" its 6". The instructions for measuring the bends and marking the conduits are included with the bender. I can email a pdf of the instructions.
I just spent some serious money for stainless steel brake lines for a car I'm restoring. Obviously the diameter of brake tubing is alot smaller than the montauk rails. However, when I asked about bending it, the supplier told me that a tubing bender is not necessary. They said that as long as I'm not totally reckless, the stainless tubing can be bent by hand without kinking. In fact, they said they never bother with a tubing bender on the cars they restore. Their restorations are beautiful.
I'm going to use my small diameter tubing bender just to be safe.
|Tom W Clark||
posted 04-07-2002 03:32 PM ET (US)
While I am not trying to discourage you in any way, I do suspect you will have a difficult if not impossible time bending 7/8" stainless steel tubing, even if it is only .049 sidewall thickness. Electrical conduit is nothing compared to stainless.
As to figuring lengths, draw it full scale and measure. Also plan on practicing on something like electrical conduit as Clark Roberts suggests if you do go ahead and try.
posted 04-07-2002 08:24 PM ET (US)
I agree with Tom on the issue that you are going to have a difficult time bending the SS tubing. A pipe or conduit bender does not have high quality shoes needed to bend cosmetic tubing without marring the finish and leaving hard spots in the tubing. You might want to see if you can find a local fab shop with a tubing bender.
posted 04-07-2002 10:49 PM ET (US)
I have a slight bend in bow rail of my 73 OR 21. Was there when I purchased it. Can it be straightened and what kind of shop can do that?
|Tom W Clark||
posted 04-08-2002 12:31 AM ET (US)
Any good canvas shop can do that for you.
posted 04-08-2002 09:06 AM ET (US)
Thanks for all the great suggestions...Now I need to decide which way to go.
posted 04-12-2002 02:04 AM ET (US)
The tubing can be bent. I used to work for a Spa and Resort in Calistoga, the mineral water reaks havoc with metal parts. It is actually worse than salt water.
We used 7/8 Stainless tubing from West Marine as custom shower curtain rods around some of the jacuzzi's. Only had one blown bend using EMT pipe bender. If you have not had much experience bending pipe I would agree that a mock up using EMT would be a good use of your time.
posted 04-12-2002 10:13 AM ET (US)
I have limited experience with bending stainless,,but I have seen Clark's work, Very professional. If he says it can be done so be it. Jim Armstrong
Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.