Alternatives to welding

[jenevers]

Will the day ever dawn when technology creates an adhesive so powerful  that steel plate repair patches could be glued onto a boat’s hull instead of having to be welded into place? Would save having to strip out the boats interior fittings.

[roland elsdon]

Magnets

[roland elsdon]

Electromagnets run off the boat batteries.

dear canalworld experts how long will it take to charge my batteries to stop the plates falling off the hull.

i an strangly attracted to this bit of piling and therefore I am now a continuous moorer.

on a serious note there are already good enough chemical bindings available but the metal has to be clean enough and the bond complete (watertight)

jaguars are glued.

 

[X Alan W]

Adhesive is used in a lot of aerospace industry as I understand it the device trundling about on Mars for the last decade or more although the built in lifespan was 3 months is still serviceable in the stuck together dept

[Bee]

Most of my old cars were stuck together with filler but the important bits used pop rivets.

[roland elsdon]

53 minutes ago, Bee said:

Most of my old cars were stuck together with filler but the important bits used pop rivets.

 I drew the line in the end the day I found myself hammering the isopon tin flat and then fastening it with the contents of the tin to the inside wheel arch of my triumph. 

 

[cuthound]

The text from my post in the duplicate (locked) thread for completeness.

"I think it is already here. Many planes and some cars are now glued together.

My youngest son has a 20 year old Lotus Elise, whose chassis is glued together, rather than welded or rivetted.

The boatbuilding industry is very conservative in adopting new practices and also gluing metal parts together requires very controlled conditions of heat and pressure to achieve a satisfactory bond."

 

Edited December 22, 2017 by cuthound

[roland elsdon]

ive enlarged (with a drill) a  rust hole in the boat before, so the boat fitted the bolt rather than visa versa, and put a patch on the footings using a piece of steel and four bolts and 'ponge' it's the same as riveting but quieter, and cheaper. We didn't have a big enough generator to weld.

you can now get fillers that set under water.

[MtB]

5 hours ago, jenevers said:

Will the day ever dawn when technology creates an adhesive so powerful  that steel plate repair patches could be glued onto a boat’s hull instead of having to be welded into place? Would save having to strip out the boats interior fittings.

 

It already exists. A lot of an aeroplane is stuck together with glue as it happens. Try not to think about that when you're in one, mid-atlantic.

I suspect you missed off a bit from your question, dealing with the cost. The price of the prepping and accuracy of machining the patch plates for bonding in place will make welding seem pleasingly cheap, even after stripping out the interior and putting it back. 

[jake_crew]

Did alot of research on this for the automotive sector when I was at work.

At best these adhesives are stronger than the metal.

But this is with perfect preparation following the instructions to the letter - cleanliness is key although some steel systems can cope with deliberate oiling of the steel (to prevent corrosion before assembly).

All methods start with sand blasting and de-greasing.

Most adhesives are single-component expoxys, and are cured at 180'C for 30 minutes under pressure.

The long term performance of these systems is still unknown, ie after many British winters with salt - let alone crash test performance after poor (back street) repairs.

[jenevers]

49 minutes ago, Mike the Boilerman said:

 

I suspect you missed off a bit from your question, dealing with the cost. The price of the prepping and accuracy of machining the patch plates for bonding in place will make welding seem pleasingly cheap, even after stripping out the interior and putting it back. 

I don’t follow you on that. Clean the existing steel surrounding the area to be patched, apply adhesive, place patch in position, keep under correct pressure/ temperature for however long it takes. Job done. How can that be more expensive than stripping out the interior and welding?

[roland elsdon]

I suspect glue on overplate rather than cut out and repair is what you are suggesting. Given bonding currently happens in a clean environment you will never get it clean enough. Cutting out and re sticking in plates pointless

[dmr]

Welding is just so good. The two pieces of metal actually become one, and any very small gaps also become filled with new metal and become one with the steel either side.

For repairs like re-bottoming then an adhesive fix would be lovely, but the base plate will be rusted and pitted and would need huge preparation to give a surface suitable for adhesive. Welding can be done with a less than perfect surface and a good welder will know that a good weld has been made.

Maybe a shot blast and an epoxy adhesive might just be viable.

............Dave 

[cereal tiller]

28 minutes ago, jenevers said:

I don’t follow you on that. Clean the existing steel surrounding the area to be patched, apply adhesive, place patch in position, keep under correct pressure/ temperature for however long it takes. Job done. How can that be more expensive than stripping out the interior and welding?

Maybe you really want a Glass Fibre Boat ? what you are Proposing Would work on Polyester.

As previously explained repairing/replacing Steel is more Economic as well as Being Practical. 

Edited December 22, 2017 by cereal tiller

[PeterF]

54 minutes ago, jenevers said:

I don’t follow you on that. Clean the existing steel surrounding the area to be patched, apply adhesive, place patch in position, keep under correct pressure/ temperature for however long it takes. Job done. How can that be more expensive than stripping out the interior and welding?

I believe that many of the adhesives require specific gaps between the two components, with the gaps needing to be tightly controlled, the adhesive is not gap filling. Very amenable to new build with well made components, but not to adding patches to an uneven aged surface.

[mark99]

Flour paste and water and wooly string with a few granny knots.

[Onewheeler]

Marmalade. You've never tried my wife's industrial strength version. It is stronger than my teeth.

[nb Innisfree]

I did my first car body repair many moons ago, cleaned up hole in wing and applied Isopon re-enforced with - wait for it - steel wool! No wonder it all started rusting again, especially after my first winter motoring on salty roads. 

Naive youth. 

[nb Innisfree]

1 minute ago, nb Innisfree said:

I did my first car body repair many moons ago, cleaned up hole in wing and applied Isopon re-enforced with - wait for it - steel wool! No wonder it all started rusting again, especially after my first winter motoring on salty roads. 

Naive youth. 

Actually my first repair consisted painting a rusty seam with a generous coat of ordinary white enamel paint,  then after leaving to dry I finished off with a nice thick coat of black cellulose paint! 

[WotEver]

9 hours ago, roland elsdon said:

jaguars are glued.

And riveted. They do not rely on adhesive alone. In fact the devs developed a brand new style of rivet specifically for the ally bodies. 

[dmr]

1 hour ago, WotEver said:

And riveted. They do not rely on adhesive alone. In fact the devs developed a brand new style of rivet specifically for the ally bodies. 

Rivets are fine for cars and aeroplanes but obviously totally impractical for boats as the water would leak in round all the holes.

...............Dave

[WotEver]

21 minutes ago, dmr said:

Rivets are fine for cars and aeroplanes but obviously totally impractical for boats as the water would leak in round all the holes.

...............Dave

Yes, you couldn’t possibly rivet a boat. 

[bizzard]

2 hours ago, nb Innisfree said:

Actually my first repair consisted painting a rusty seam with a generous coat of ordinary white enamel paint,  then after leaving to dry I finished off with a nice thick coat of black cellulose paint! 

 

8 minutes ago, WotEver said:

Yes, you couldn’t possibly rivet a boat. 

Cellulose paint on top of oil based enamel would have reacted instantly and all pickled up, Around the other way, ok.

[MtB]

38 minutes ago, dmr said:

Rivets are fine for cars and aeroplanes but obviously totally impractical for boats as the water would leak in round all the holes.

...............Dave

 

You could stick them on with a really strong adhesive, if there was one!

[roland elsdon]

Could you weld the rivets in place?