Build a shackle guard

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An acquaintance told me that he needed a shackleguard. And I never had heard about it. A bit of investigating (Google is your friend) and I found it online. A shackleguard is a disc with some holes in it. In the middle is a hole where you put a rope through. Lead the rope from the top through the hole. At the bottom you then tie a shackle to the rope. The shackleguard is wider as the shackle. The purpose is to prevent the metal shackle to slap against te boat and damage it. The guard is made of plastic and that is softer as the metal of the shackle and will not damage the boat. So it is a typical marine thing.

I would have posted a picture but they are (as I presume) copyrighted by the manufacturer, so Google it yourself and you will see how it works: https://www.google.com/search?q=shackle+guard&client=firefox-b-d&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiPgcL_-rT3AhWtgf0HHQbFBHAQ_AUoAnoECAEQBA&biw=1211&bih=891&dpr=1

Challenge accepted. How difficult could it be to make one myself.



I started with drawing a solid circle in the Gimp (free picture editing software) and then put some holes in it.



Next I used the online website Convertio ( https://convertio.co/ ) to convert my jpg file to an SVG file.



Then the SVG file was imported in Tinkercad and given a hight of a few cm and a diameter of 58 mm and a hight of 16mm. This process was described in detail in a previous story which you can find here: http://lucstechblog.blogspot.com/2020/10/3d-printed-anchor-hook.html I did use different converting software in that story but the priciple stays the same.

When that was done I made a sphere with a diameter of 58 mm.



Then I created two boxes functioning as holes. One box was positioned about half a cm from the middle of the sphere and the other one about half a cem below the middle of the sphere.



The sphere and the boxes were grouped and a nice disc is that way created.



Lower the disc on the workplane.



Now put the model next to the sphere



Rotate the vieuw till you are looking on top of the model.



Create some cilinders that fit the holes and place them into the holes.



Select all 5 cilinders and convert them to holes.



Remove the model by selecting it and clicking delete.



Group the holes.



Move the holes as a group and center them on your disc.



Group the disc and the cilinder-ho;es and you are done.

You can now export your shackle guard as an STL file.



I imported the STL file in my creality slicer and sliced the design at .3mm That is a bit course but this design does not need details. It needs to be functional. The slicer shows that printing will take 47 minutes and that is a bit optimistic.



And here you go, the completed print.

All in all the designing took me about 45 minutes, and printing about an hour.
Please note that my design has a rounded edge while the original has a straight edge.

I printed this in PLA, because it is what I had at hand.
PLA is said to be deteriorating in the open. However my experience is different. My fence caps which I printed in 2015 still show no sign of falling apart:
http://lucstechblog.blogspot.com/2015/07/fence-caps-few-moths-ago-my-son-in-law.html

I don't know if any of you are interested in the STL file to print it yourself. If you want it, just drop me a note by e-mail.

Mission accomplished, my aquiantance glad and guess what: I earned myself a few boat trips this summer.

Till next time.
Have fun

Luc Volders