As part of putting my Nacraa 5.2 forest cat back together, I've been looking at sources for new end caps, since the boat only had one remaining. I found them online for $30 each, which is too rich for my blood. I then ran across the turned PVC plumbing cap solution so I bought a set, only for them to sit for a couple years because I don't know anyone that does lathe work.
Then earlier this week it hit me that I have an architecture firm with CAD software and a 3D printer. So I took my one remaining end cap and a set of calipers and drafted up a replica in the computer. The one change I made is I took the center hole for the righting line and increased the radius so it won't wear on the shock cord.
I sent it to print, and I think it came out pretty good. Eyeballing it, it looked like just about the right size.
I took it home to put on the beam, AND...
About 1-2mm too large. Oh well, I resized it and have a new one printing now.
With the 3D printing technology, I can really make these things look like whatever I want, whic his pretty neat. We'll see how it goes...
Those are very good locking, How much did they charge, was it really less then the
black caps from Murray's
ohmsj
Nice. I 3D print often and the PLA parts often come out slightly oversized, a few percent. What material are you printing with? PLA?
ohmsj wrote: How much did they charge, was it really less then the black caps from Murray's
I should have specified - I own the architecture firm. The 3D printer belongs to my business partner two offices down. Cost to me is effectively $0.
ctcataman wrote: What material are you printing with? PLA?
Yeah, we use PLA in our printer. From what I've read, it seems to be more outdoor resistant than some other materials. I guess time will tell. If it doesn't last longer than a season... print another set!
Awesome job. I have a buddy looking into printing end caps for the Tornado.
I believe the hole in the end cap is for the shock cord for the trapeze, not the righting line.
Have you considered just leaving the end caps off? They are purely cosmetic anyway. Some of the boats I have rebuilt have had considerable corrosion where the bolts go through the back up bars within the cross tubes making it a lot harder to get the boat apart. Some of this is probably due to not rinsing the salt water out of the cross tubes. I was more inclined to rinse in there without the end caps. I filed down the sharp edges so the shock cord for the trapeze would not wear quickly. If you're doing a complete restoration where looks matter, go for the end caps. Take them off and rinse out the cross tubes when you know you've got a lot of salt water in there. If you can get the bolts unscrewed and remove the cross tubes be sure and grease the bolts and apply a good silicon bedding compound to the saddles before reassembling.
shortyfox wrote: Have you considered just leaving the end caps off? They are purely cosmetic anyway.
The caps are not purely cosmetic. They center up the trap bungee in the front. They help support the open end of the crossbar and help prevent crushing. They smooth the crossbar opening to reduce injury. And maybe as important as all the other functions KEEP WASPS and birds OUT.
Edited by leeboweffect on Nov 15, 2019 - 10:47 AM.
shortyfox wrote: ...be sure and grease the bolts and apply a good silicon bedding compound to the saddles before reassembling.
I actually have the whole boat apart right now, so I have that in the plans for when I reassemble. I was going to use faring compound to do the bedding, actually.
leeboweffect wrote: The caps are not purely cosmetic. They center up the trap bungee in the front. They help support the open end of the crossbar and help prevent crushing. They smooth the crossbar opening to reduce injury. And maybe as important as all the other functions KEEP WASPS and birds OUT.
My original set of beams had problems with crushing and yes, were full of wasps ans squirrel nests. Two reasons I want to put end caps on the new set.
Edited by loquinho on Nov 15, 2019 - 11:29 AM.
I stand corrected on the end cap discussion on you're end cap issues. I have no experience with the older Nacras with the round cross tubes. The Nacra I used to have had rectangular cross tubes and perimeter supportive back up bars so crushing was not an issue. Good luck!
way to go loquinho!
i (also an architect) suggested that someone do this back in 2015 so i'm glad to see your success.
j
https://www.thebeachcats.com/index.php?module=forums&func=viewtopic&topic=15434
very cool man, very cool. nice to see people creating solutions.
I’ll take a set of 4 if you’re selling them..5.7
I too have CAD designed the NACRA beam caps and have printed them out. They fit very well. Happy to share these files, or print you some caps, just message me.jsdiii@comcast.net
Edited by sduff on Mar 21, 2021 - 11:07 PM.
If there is any concern about the PLA being affected by UV exposure, a coat or two of marine paint would fully weatherproof them and look good.
Just about to order a $120 set from Murray’s for N5.7..
How available are yours?
Interested.
Edited by jd91t on Mar 22, 2021 - 12:19 PM.
4-3D printed NACRA Beam caps available for the price of 1 Murray's cap + Shipping. Email me at jsdiii@comcast.net.