We want to thank everyone in the Kickstarter community from the bottom of our hearts. When Nick and I invented the locking shackle we thought the retail market would just eat it up. But when we took it to the retailers, they looked at it and said, "Beautiful shackle and cool locking mechanism. Titanium, huh? Corrosion resistant, too. How long will it last?"
We told them we could offer a lifetime warranty because it was so strong and would last virtually forever. Then we showed how this shackle could be sold for less than comparable 316 stainless shackles.
Then, they blew us off!
We are like, "What the. . .?"
Well, it turns out that retailers don't like products that are perpetual. They like products that wear out and break so they can sell them over and over.
So again, Thank you! We can now go into production with this design.
Our shackles are precision investment cast out of Grade 5 (6Al-4V) titanium. Grade 5 (6Al-4V) titanium is an aerospace alloy that has a yield strength 3-1/2 times greater than 316 stainless steel, while being 44% lighter. Best of all, it is corrosion free in the natural environment, including saltwater!
The common misconception is that since it's made out of titanium, it's going to be expensive. If you look through our website, you'll see we are making titanium products affordable. And if you help us crowdfund tooling and production runs, we can really get the cost down. As you can see, the rewards are comparable to 316 stainless steel shackles, even though ours are stronger and lighter.
The 5/16 inch version of this shackle has an amazing breaking strength of greater than 8000 pounds (3628 kg), giving it a safe working load of about 4000 pounds (1814 kg).
The pin locks in place!
There is a locking mechanism which is engaged when the pin is tightened into the shackle body. Each click further tightens the lock, negating the need for seizing wire to prevent the pin from becoming accidentally unscrewed.
The pin is captive in the shackle body, reducing the chances of dropping or losing it. Yet it can be completely unscrewed and removed if necessary.
So where do I use my new shackle?
Heavy load lifting:
An old fashioned tire swing!
No lost keys or thieving pickpockets here!
Climbing (Tree, Rock, Mountain, etc.) - Safer and more reliable than a carabiner.
- Safety cables and construction rigging
- Anchors and moorings for boats
- Towing (Boats, Cars, Water skiers, etc.)
- Tying down race cars to trailers
- On and on. . . so. . . How about:
A Titanium Tug of War!
The other designs
We already have a prototype of the 5/16 inch shackle, and because no "one size fits all," we want to produce larger and smaller sizes, too. As the saying goes, "The right tool for the job!"
As mentioned before, our shackles are made from aerospace grade (6Al-4V) titanium by investment casting in multiple factories that are members of the Allied Titanium Factories' Association.
The first step is the creation of a UPD Sheet (a mechanical drawing detailing the measurements of what is to be manufactured, including a lifelike animation). The animation is from a machine executable 3D CAD file. This CAD file is loaded into sophisticated software that analyzes the contraction of the metal as the molten metal cools and positions reservoirs that the shackle can "suck" from as it cools.
Once the computer analysis shows that the shackle will cast accurately without deforming, a master pattern is printed out using 3D printing technology. This pattern is used to make a mould, known as the master die. The master die is used to cast wax patterns, one for each shackle to be produced, and these wax patterns are clustered together into trees, similar to the photo below:
When finished, the wax trees are dipped over and over in a ceramic slurry to create a ceramic mould, called the investment. Here is a slurry tank from a member of the Allied Titanium Factories' Association:
The investment is placed in an oven to remove the wax and harden the ceramic material just like pottery is fired.
Here is where titanium investment casting and other types of investment casting part ways. The fired investment is placed in a vacuum furnace and is heated, and we mean hot! Another vacuum furnace above holds the molten titanium which allows the titanium to run down into the investment. All of this must happen without the molten titanium coming into contact with air. Here is what the machinery looks like:
When cooled, the investment is removed from the casting furnace and the ceramic shell is vibrated off of the titanium. The shackles are then cut away from the reservoirs, sand blasted, polished to a near mirror finish. Afterward, a few shackles are submitted to a breaking load test.
With the breaking strength established, we can now split that in half to arrive at the safe working load with every shackle being pulled to its safe working load. As you may know, few if any other manufacturer is willing to load test every style of shackle they produce.
Shackle lifting 5000 pounds of metal:
After load testing, the shackles go to Quality Control where they are measured and visually inspected to make sure they meet the specifications on the UPD Sheet. From Quality Control, they travel to Quality Assurance, where they are inspected once again, packaged and shipped out.
Investment casting and load testing like this are extremely labor intensive and time consuming. The two processes together produce a superior product that we can proudly stand behind by offering a lifetime, free replacement warranty on all of our shackles. All you need do is return the damaged shackle and we will send you a brand new one, free of charge.
Risks and challenges
As previously stated, casting is a delicate, time consuming process. We have already done a 5/16 shackle production run of 100 and tested them in the real world for over two years. We have the designs, UPD Sheets and CAD files for the other sizes as well as the factories to produce them.
The only problem we foresee is that if demand is high for some of the sizes, it could delay production for a few weeks. If there are any delays, we promise to send out emails immediately.Learn about accountability on Kickstarter
- (30 days)