I’m interested in talking to people with skills related to 3D scanning, modelling, CAD, printing, and creation of parts production plans.
The driving concern behind this is this: as the boats grow older, we’re drawing down the supply of various original parts, both Nonsuch-specific and from manufacturers no longer in business. At the same time, we’re seeing a lot of new capabilities for 3D printing and custom manufacturing (e.g., outfits like https://sendcutsend.com). I’m wondering if it’s at the point where the INA could start a repository of CAD models for parts and a list of services for producing them. If so, members could use that to get one-offs or small runs of parts done.
The key questions are: is this feasible and, if so, what would it entail?
I’d like to use this thread for an ongoing discussion. In addition, Rahsaan Dobbs and I were planning to have a Zoom chat in a couple of weeks on the topic. That’s what he was referring to in his comment in the thread about 3D models of N26s ( Does anyone have blueprints for a 26 Classic? ):
That Zoom meeting is scheduled for Sunday, March 15 at 10:00 am Pacific time / 1:00 pm Eastern.
If you’re interested in participating in it, drop me a note at RTNeches@gmail.com and I’ll send you an invite.
Sounds like a great idea. I’m more interested in the process than the finished product but I’m sure that interest will shift in time. Excellent idea Bob.
This is a very relevant initiative. In my daily CAD work for a marine canvas shop, I deal with these exact challenges regarding 3D measurement and parts production.
Regarding the feasibility of a CAD repository based on scanning: we have researched high-end 3D scanners and LIDAR extensively, and for yacht exteriors, they are simply not reliable enough. The main issue is Accumulated Drift.
To give you a practical example: we tested top-end handheld 3D scanners on a cockpit. After scanning a loop of about 6 meters (returning to the starting point), we found deviations of up to 30 centimeters (12 inches) in every axis. For manufacturing parts that need to fit perfectly, this is a dealbreaker.
The reasons are specific to boat environments:
Surface Interference: High-gloss gelcoat, polished stainless steel, and dark windows create “noise” or fail to register at all.
Lack of Reference: Long, smooth hulls offer very few geometric anchors for a scanner to “lock” onto.
Line of Sight: Scanners can’t see “around the corner” or behind frames without constant repositioning, which compounds the drift.
For these reasons, we use a Prodim Proliner. Because it uses a physical pull-wire, it isn’t affected by reflections or lighting. It provides the exact coordinates with mathematical certainty, which is essential if you want to send files to services like SendCutSend.
I have a Proliner at my disposal and can perform any measurement on an N36. In principle, the entire boat can be digitized—inside and out—into clean CAD models.
Unfortunately, the Zoom meeting is in the middle of the night for me, so I’ll be sleeping then, but I am happy to continue the discussion here in this thread!
Although this topic was started as a split-off from a discussion of hull models, I really think the near-term directions are more likely to be along the lines of small parts. In some cases, this might involve 3D printing. But, in other cases, it might be along the lines of CAD instructions for bending or milling other materials.
Examples:
Your own design for deck drain screens in ( Little autumn projects ) – which reminds me that I was supposed to work with you to get that up on Members Tips & Projects
I’ve seen 316 stainless large pipe collars sold in industry which look like they might be adapted into replacement Nonsuch mast collars. The ones I’ve seen are very affordable, but 0.625” too large for an 8” diameter N26 mast. But, how hard would it be to spec a spacer that could insulate it from the mast and fill the gap?
There are a bunch of mast and boom pads which have holes drilled through them for cheek blocks which are no longer made. To avoid drilling more holes in the masts or boom, could someone come up with an adapter with the right base curvature that fastens with the old holes underneath but lets you place different blocks on top of it?
I misunderstood you initially; I assumed you meant structural parts when you mentioned aging yachts, especially given your interest in a sprayhood.
For instance, I was thinking about digitizing a rudder—just in case it falls prey to an orca off the coast of Spain or Portugal—or things like replacement cockpit access doors and measuring the cockpit coaming topsides to have a custom-fit synthetic teak deck made.
I see now that you’re focused on scanning smaller parts. For simple objects like adapter plates to fit new hardware into old screw holes, you can get very far with just a pair of calipers and basic measurements. A 3D scanner isn’t really necessary for that, nor for things like screens, drain meshes, and so on.
My approach was slightly different. I have been doing this scanning since 1997. The type of scanner I use mostly is for surveying buildings, industry and infrastructure, (though I have scanned many ships and yachts) has a 100 meter range, and was at one time worth three times as much as a N26, but now used scanners are going for much much less.
This approach requires many setups and some skill but it’s doable. The 360 degree scan has voids in the interior. To fill them we combined scans from a hand held , so this method solved the “drift” problem. Accuracy can be really good to the point where moving about on the boat and it’s movement(flexing of the hull and cradle) lead to larger errors (3 or 4 mm) when scanning the deck and interior.
Anyway, it’s not really practical for modeling little yachts from a business point of view. New scanners may change that. I’m just using tool(s) I have.
3D printed parts for the Nonsuch usually just require a tape measure or calipers. Then print several parts until they fit.
Image shows raw point clouds of a N26. Millions of points. Not much skill required to this point. In the past some effort was required to distill this cloud down to a clean surface. Lately more and more CAD and 3D Graphics software try and automate this step but so far I found the results are poor and my old way is still cleaner.
A friend of mine modelled these for me digitally and then I had the kids in the manufacturing program at the school I teach at make them. These are chocks/fairleads that our N30C #27 never had. I will ask my friend if I can make the file available, but he runs a business so there may be a cost
Any objections to moving the Zoom meeting on this topic back one week, from Sunday the 15th to Sunday the 22nd?
I’ve always had good luck up until now, but this time I’ll be coming back late Saturday night from a trip abroad where maybe I shouldn’t have drunk the water.
Did we turn the clocks recently back or forward? Forward right ? Now wouldn’t that be further into the future? So if we turn the weeks forward, wouldn’t that be later on the calendar?
Sorry I couldn’t help it.
I will look in to it.
Brian
There’s a similar debate about an old blues song, with various artists differing over whether the one who rejected them will get theirs further on up the road or further on down the road. Either way, it’ll be later.
Just a reminder for anyone interested in joining the Zoom discussion on this topic: it’s scheduled for this Sunday, March 22nd, at 10:00 am Pacific / 1:00 pm Eastern / Zero Dark Thirty Netherlands time (sorry, Mark ).
There’ll probably be more posts on this and related topics.
In the meantime, a small group of us (the people who’ve posted above) participated in the Zoom meeting mentioned above. We’ve agreed to work off-line on some concrete proposals for actions on this topic.
Talking will continue on the Nonsuch Community Forum, if you’re just interested in following. Some actual work will be in progress in a smaller group, and will re-appear here if/when ready.
If you’re interested in volunteering to work on that little project, drop me a private note and I’ll add you to the working group. Talking will continue on the Nonsuch Community Forum, if you’re just interested in following.
).