Tube bending idea?

[W.olly]

Hi all, i am not far off, well this spring to need to start making the hand rails and bow rail for my boat. I will be using 3/4" ( 19mm ) polished stainless tube with a 1.5mm wall.

Now the idea is one i have seen using ally channel to make a kit car window frame.

Plywood 18mm to rest the tube on which has a radius of 3" ( 75mm ) then either side half way up the tube height again 18mm plywood, so sits about 10mm above the central part, then a madrel to form the tube around the radius, this way the tube will not splay out.

Now not sure if it will crinkle on the raduis.


Your thoughts

 

[chevy2]

I wish you luck but to be honest you're gonna need to put that stainless tube through a tube bender correct for thinwall tube, especially on a tight 3" radius

 

[W.olly]

I wish you luck but to be honest you're gonna need to put that stainless tube through a tube bender correct for thinwall tube, especially on a tight 3" radius

so a no go idea , worth a thought.

Any suggestions on non to expensive tube bender for thin wall. I was thinking of getting elbow joints but the cost is getting daft a si need a good 16 off top of my head.

 

[addjunkie]

You could try a conduit bender, with correct die, hilmor el 25 something like that

 

[chevy2]

You could try a conduit bender, with correct die, hilmor el 25 something like that

Once again good luck, i reckon it'll crack the ali former,
i broke one after several bends with the same thickness steel tube and stainless is tougher.

 

[chevy2]

so a no go idea , worth a thought.

Any suggestions on non to expensive tube bender for thin wall. I was thinking of getting elbow joints but the cost is getting daft a si need a good 16 off top of my head.

You'll need a rotary type bender with the 1" former, Stakeys for example,
At a real rough guess you'll be looking at 4-500 quid,
if its only the one job then buy the 16 bends.

 

[addjunkie]

I built this with a hilmour conduit bender...1 inch steel tube 2.5mm wall.

 

[hotrodder]

The old Hilmor type conduit are waaaaay better quality than what you can buy new and with a bit of hunting around you can get cast iron dies for them. Mine (branded as a Record) bends 3/4" 16swg stainless tube pretty cleanly but not on a 3" CLR, iirc the dies are all around 4.5D i.e. more like 90ish mm centre line radius

Obviously depends on what's locally available in the way of hire shops but some of them do rent 'proper' tube bending kit as well as pipe stranglers for example http://www.broughtonplanthire.co.uk/access-gear/tubela-15-54mm-ratchet-assisted-copper-bender

 

[Kent]

Could you post a drawing possibly? So I can understand what you want to end up with

 

[500e]

Have lined dies before now to get pipe diameter correct

 

[W.olly]

Could you post a drawing possibly? So I can understand what you want to end up with

These are some pics of what i am after roughly,

for the rear deck it will be a low hight 90Deg rail ( 8inch ) around both corners each leg around 24inch long similar style as the hand rials above.

I havnt done any drawing yet so this is just an idea. no darn sketch up/ paint on this new laptop yet.

 

[W.olly]

Have lined dies before now to get pipe diameter correct

When i the large 12ton clarke pipe bender i used lead sheet to help, worked a treat.

 

[Kent]

For the grab handles a hydraulic bender like a tubela should work
Cut the leg so it forms longer than you need then trim back
For the proper bow rail think these need rolling or you just won't get the large even radius
I should then joint the sides in with an internal splice or welds

Rather than buy in the kit if it's just a one off I should get them done out
Off template

Other than that it's sand packing and a torch

 

[addjunkie]

As weight wont be an issue use a heavier wall tube, and a clarke pipe bender, pack out dies with sheet ali, you should be ok.

Looking at the pushpit you could do a series of small bends close together for the bow. Or change the design slightly with a short flat accross the bow, and equal bends either side.

I made one of those 25 years ago out of 1 inch tube bent with a pipe bender, mad with pipe then galvanized so it didnt really matter.

 

[Wendelspanswick]

For the grab handles a hydraulic bender like a tubela should work
Cut the leg so it forms longer than you need then trim back
For the proper bow rail think these need rolling or you just won't get the large even radius
I should then joint the sides in with an internal splice or welds

Rather than buy in the kit if it's just a one off I should get them done out
Off template

Other than that it's sand packing and a torch

Use a Tubela on tube with a 1.5mm wall thickness and all you'll end up with is a kinked flattened bit of scrap!

 

[Kent]

Use a Tubela on tube with a 1.5mm wall thickness and all you'll end up with is a kinked flattened bit of scrap!

With packing? Sure that's how I used to do similar without packing but is been a fair while and memory fades
A roller won't do those handles it's too tight so that only leaves a former similar to the hillmore only bigger. Or packing and heat
Still stuff like this needs sending out to people who do it a lot

 

[W.olly]

I was going to, an still mite, make the bow from copper tube and fittings and send to be made, the hand rails i can buy as in the pic ready made or make from Sapele hard wood, the low rear deck rails will also be a one off so they would be sent out in copper to be made.

I could make it from 25mm, no big deal in size difference and do as addjukie has dome on his trike.

The radius i said can be increased also, the pics are just a rough idea as said a si would like to include a small seat in the front of the bow.

 

[addjunkie]

The best way to include the seat is to use this style

http://www.yachtsnet.co.uk/boats/w13514/w13514.htm

But you need to be carefull if you use a bow anchor over a roller, can make getting the up difficult

 

[W.olly]

Just been looking at a similar set up addjunkie, the idea i had was a small wooden slatted seat which is removable if/when anchoring.

I was considering using these for the rear deck rail, just a bit to sharp a corner, but then.......
All i would need then is straight lengths to slot in, thes efitting are for 25mm tube aswell.

This is the rear deck so maybe a sharp corner will be ok.

The boat is in better nick now though lol.The rail will be sat on the blue area on the gunnel area to the middle of the transom.

 

[the snooper]

The boat is in better nick now though lol.The rail will be sat on the blue area on the gunnel area to the middle of the transom.

photo's