Island Packet Chainplate Replacement

[model 10]

Originally Posted by a64pilot

The price is a fraction of what it once was, perhaps we are just conditioned to think it's very high priced?

The Russians have most of the Ti. You got Russky chainplates?

[a64pilot]

Originally Posted by Guy

The Russians have most of the Ti. You got Russky chainplates?

That used to be true. Of course fake businesses were set up to buy Ti to build the RS-71 and just to get Ti back in the day.
What confuses me if you look it up Titanium is one of the most common of elements, so why is it so hard to get? I don't know.

[a64pilot]

Seems China is the biggest producer now
https://en.m.wikipedia.org/wiki/List...ium_production

Titanium is the most common element in the earths crust?

[Frankly]

Curious, the tangs on the lowers must be bent to get them to line up with the pull. Does Mack do that before installation or after. Tom Broome told me that back in the 304 days the factory had a long pipe that had a fitting that slipped over the end of the tang and then give it the old heave ho, not sure what they did on the larger 316 days. I would think with the individual units a little heat and pre bending would be preferred.

If Mack is going to put the strands around the angle why even include the cross flat bar?

The failure above the angle has been the more typical based on my 10 years of observations, and you are right bad news follows shortly there after.

[a64pilot]

I don't know, I wondered about why include the piece of tie bar myself if it's not used, seems a waste.
Perhaps the video is wrong?
By bend I assume it's different for each plate? Or it would be pre bent?
We sent one piece of chain plate to Allied Titanium with instructions to make eight just like this. Colin sent it, hope he knows what he was doing.
Ti may not be so easy to bend if it needs bending, never tried. Only other Ti I have other than the blade grip is a Lightspeed bicycle, never tired bending it, and the blade grip? Supposed to take a direct hit from a 23 mm armor piercing cannon round, doubt it bends easy either

[a64pilot]

OK, first chainplates are out, did not look bad at all to me for 30 yr old plates, however one tie bar did break on removal. Seems it had begun to "rot" which I assume is inner granular corrosion.
Maybe they had several years left in them? Or maybe they were ready to break, without conducting a pull test on each one, I don't think there is a way to tell.
Anyway they are not installed the way the video shows. They are installed The way IP did at the factory, that is with thickened resin to bed the angle in and the unidirectional glass draped over the tie bar, not the angle like seen in the video.
On the angle, seems the angle is known for each one and is given to the fabricator so that each one is pre bent as opposed to bent after installation. I can see how bending on installation might be interesting, it may just break the bond between the plate and the hull?

[Kenomac]

Your next titanium purchase will probably be hips and knees.

[a64pilot]

Left knee, almost certainly.
I hope not hips, but who knows? I hope your incorrect.

[Stumble]

Originally Posted by a64pilot

That used to be true. Of course fake businesses were set up to buy Ti to build the RS-71 and just to get Ti back in the day.
What confuses me if you look it up Titanium is one of the most common of elements, so why is it so hard to get? I don't know.

The following is mostly unrelated to boats just titanium...

Ti is incredibly common, in fact we all buy a lot of it every day. The problem is that Ti is almost always found as titanium oxide or TiO2. In this form you probably have a couple of pounds laying around the house. Most products that are white or colored have Tio2 as a coloring agent. From toothpaste to if it's white it's almost certainly thanks to titanium. It's also used as industrial coatings (Ti drill bits for instance).

Because Ti is so incredibly reactive to oxygen, outside of a noble gas room you will never touch titanium, because it oxidizes almost immediately with the free oxygen in the air. Kind of like aluminium but much, much faster. The oxidation rate is generally given as 10 nanoseconds to form a 6nanometer deep shell. Even after years this layer is pretty stable, eventually reaching about 10nm deep. Technically it continues to form forever but the rate stops except in geological terms. What this means is that within nanoseconds of being scratched Ti has healed the scratch and I simply back to chemical inertness.

This is the same process that protects stainless and aluminium, a thin oxide surface layer protecting the structural metal. The difference is just that TiO2 is functionally immune to common chemical attacks. Chloride (ie salt water) is very aggressive at destroying chromium oxide for instance, but has no effect of Ti at room temperatures. There are some chemicals that can, but they are primarily very high strength reducing acids that no one outside a chamical lab should be touching.

So if Ti is so common (it's the 4th most common element on earth), and useful why is it so expensive?

Basically because of the cost of separating out the Ti from Tio2. Ti is refined via the Krull process, which means taking Ti ore and reducing it with chloride at 3,000c or so Tom form Ti Chloride. Then that has to be reduced with magnesium at 1200C. All of which has to happen in an oxygen free environment flooded with argon (typically). Think about a protected welding box the size of a foundry.

Until around 2005 (iirc) it could only be done I need small batches instead of continuious production further adding to the cost. Since then new methods have allowed continuous production which has dropped costs a lot, but metal countries cost a lot to build and go up slowly.

Right now the biggest driver of Ti cost however is no longer production it's that it's use is so limited. Because it's so rare inventory costs, carrying costs, and 'we have it and you want it surcharges' are the primary barrier to costs coming down.

As the market gets bigger economies of scale are driving down prices rapidly. Right now steel prices run about $1 a pound, and Ti is about $6/lb. but Ti is about half the density, so for a given volume, say the amount in a bolt the cost of the base metal is about 3 times what mild steel costs (actually pretty close to what stainless runs).

The problem is that WestMarine for instance probably buys... I have no idea, a few million stainless nuts a year in all sizes? Where as a production run of titanium nuts in the 2,000 pieces range was considered a very big order. I have actually quoted this btw. On an order of 5,000 Ti bolts I could beat the retail price for 304 stainless. Not quite the wholesale price, but getting very close. At 50,000 pieces I quoted about 20% more than 304 stainless wholesale (but not OEM) prices.

I really do think we are living thru the last decade or so where stainless is common in the marine industry. In 10-20 years it will be an anarcronism. Because for a small price premium you can have hardware that will last forever.

[missourisailor]

Strictly for comparison.
Here are some shots of the Garhauer made, replacement chainplates for an IP 35.

Metal Marking


Larger Image:
http://www.midwestsailing.com/ALYSII...F/P1010650.JPG

All Overview


Larger Image:
http://www.midwestsailing.com/ALYSII...F/P1010653.JPG

Upper Shroud Tang- Showing Angle



Larger Image:
http://www.midwestsailing.com/ALYSII...F/P1010651.JPG


Overall End View



Larger Image:
http://www.midwestsailing.com/ALYSII...F/P1010654.JPG

I bought these several years ago at a cost of around $1500.
Three yards made bids on the job, but all backed out when the time came to do the work. Lucky for me, I did not make any down payments to them. Only paid for the plates, which as you can tell, I still have.

[Frankly]

The knees are part stainless and part titanium. If I remember correctly the part that rubs on the plastic is stainless (good surface finishing) and the part which is fixed to the plastic is titanium (surface finish less important but light). A number of years back, but I remember asking the OS why the different metals as I was playing with his model in the exam room. My wife, I am just starting into the knee hurting stages.

With the individual units pre bending the tangs makes a lot of sense, not sure how easy to get into place if you go the original one piece assy.

Keep the info and pictures coming. Kind of like death and taxes us IP guys going to get there one way or another.

[missourisailor]

Originally Posted by Frankly

With the individual units pre bending the tangs makes a lot of sense, not sure how easy to get into place if you go the original one piece assy.

One person, and only one of the many I have talked to about this, said his yard cut the long 1"x0.25" piece at two places. Making three parts per side.

I'm not sure if this practice is good or bad.

[estarzinger]

Seems like carbon chainplates would make sense here, given all the work you have to do for the metal ones. They are well proven and you would never ever have a leak again (and no sealant "maintenance").

[a64pilot]

Originally Posted by missourisailor

One person, and only one of the many I have talked to about this, said his yard cut the long 1"x0.25" piece at two places. Making three parts per side.

I'm not sure if this practice is good or bad.

That is the way they are installed at Mack Sails too, except we had them made individually as I assume that is cheaper, if nothing else in shipping.
To replace the whole thing in one piece would I believe entail removal of a bulkhead, which would be a lot more work.
I do not believe the long tie bar contributes any to the strength myself as it's not really glassed in with unidirectional glass, just covered with woven roven, which I think turned out not to be a good ideal, maybe newer boats are not covered?

[a64pilot]

Originally Posted by estarzinger

Seems like carbon chainplates would make sense here, given all the work you have to do for the metal ones. They are well proven and you would never ever have a leak again (and no sealant "maintenance").

You could, but that would be a complete redesign, not simple materials substitution, and therefore for just one boat, I think would be way more costly.
With Ti, you don't have to worry about the sealant either, except to keep water from leaking into the boat, but it won't cause any structural issues or degrading of the chainplates.
If the carbon plates penetrated the deck, you would still have the sealant issue from a leak in the boat issue as well.
I don't know enough about carbon, I know a little about Ti from working with it on aircraft. Not as much as Stumble though.
However I do not think we will see SS go away, Ti is the devil to machine, obviously it can be done, just takes a lot of time and time is money, so anything requiring much machining, I think will still be SS for a long time.
However who knows, Boeing and General Electric is having parts 3D printed out of Titanium now.