Design features of the Mumby Cyber 48 - An aluminum performance cruising catamaran
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- Опубликовано: 7 авг 2024
- Design features of the Mumby Cyber 48 - An aluminum performance cruising catamaran.
So we've seen the building...the fitout... questions and answers... here's some of the awesome features of this great design.
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0:00 INTRO
01:26 ALUMINUM/ALUMINIUM
03:07 PERFORMANCE
03:27 LIGHT WEIGHT
04:38 HOW TO STAY LIGHT
06:05 SKINNY HULLS
06:48 STREAMLINED DECK
07:28 BRIDGEDECK
08:27 DAGGERS
10:34 SAIL PLAN
12:47 ENGINES
14:05 PROPS AND BEACHING
14:37 KICK UP RUDDERS
15:16 HELM
16:40 WELDED FIXTURES
17:23 WELDED DECK FITTINGS
17:58 DECK SPACE
19:17 HATCHES AND DOORS
22:48 GALLEY
24:35 KISS
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ABOUT US:
Jupiter² was built in the Philippines by an Australian designer for Jamie. During his time away from work, Jamie lived on board and cruised South East Asia. One of his life dreams is to sail around the world. His plans came together at the end of 2018 when he met a Filipina lounge singer in China. Princess was yearning for a vacation since she had been working many years to support her family. Finally, her siblings got their own jobs and she decided to join Jamie on Jupiter² and go sailing. It was a wild decision for her because she had never sailed before. For the first time, they sail for two weeks around Phuket, Thailand. She began to see what Jamie love about the sea. They both resigned from their jobs in early 2019 and began cruising full time.
Hopefully some inspiration to "Quit Job and Go Sailing".
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#aluminumcatamaran #performancecruisingcatamaran #mumby48 #limitededition
I absolutely love this boat! As a software engineer I feel like it was built the way I would build a boat, so that it’s easy to work on and fix yourself. Whenever I see these multi million dollar boat I’m just counting all the things I need to pay someone to do and be waiting for someone to fix. It looks like the least stressful boat. I love it.
easy to fix. Cool
Good review, makes sense to me as a 40 year shipbuilder.
Nice...Thanks WJ
High praise indeed. As someone very new to all this, is the Aluminum VS The Rest based on fact? Or is it akin to the Ford VS GM? Any help is appreciated.
That's a great, minimalist design.
Yeah Jay, it's got everything we need.
After this video, Mummy's waiting list will be very long. I'm also thinking of the current serious problems with production catamarans like Lagoon that will change the direction of the off-shore boat market. Had I seen this a few decades earlier...idle to think about it. I will pass on this very compelling and well done episode. Thanks for this.
Cheers Albert....tks
@@SailingLifeonJupiter hey boss quick question do you still need zinc anodes
Yes, the Mumby 45' and Mumby 48', and Mumby 50' are tremendous for blue water and diving and adventure catamaran purchasers, and highest qualtiy, higher quality than many other mass manufacture or semi-custom or custom sailing catamarans or motor catamarans.
Yes, need sacrificial zinc anodes on any water craft having metal in contact with the seawater. (Well, perhaps somewhere out there a boat has only noble metal gold, silver, or bronze...in contact with the sea. )
@@3091752 Yes, same as any boat that has 2 or more types of metal in contact with the water, including plastic composite boats.
Videos of cracked bulkheads on Lagoon's brought me here 🤣 Exellent vid 👍👍
Hey cool Ben...Welcome
Good review of your aluminum boat. Excellent points made on every topic, security to engine access to points of sail to holes in the deck. Great video.
Thanks so much Myron
Good video. The boat is a nice way to combine comfort and using sail, not engines. Just noticed, you look like a young Tom Jones! (the one who sings What's New Pussycat) Happy Trails
Serious! I wish I was packing what TJ has!
Good Aussie attitude. Simple, practical, performance oriented and no bullshit.😂
Excellent view, thanks so much!
Excellent presentation!
Thank you for taking the extra time to perform a brilliant review!
I'm subbing!
Thanks for the great review…love the features and design of your Cat and can’t help but be envious mate…enjoy and safe travels always!!
Cheers Mike
Excelente tour!!! Aluminio es lo mejor.
Thanks Marcelo
New build on plan for a friend so very helpful to see an in depth tour. Thanks.
Glad to hear of another Mumby on the way. Cheers
Thanks for sharing! Great information, it's a beautiful cat. Simplicity is key!
Cheers for that.
Thank-you very much for this rare video content - explaining your design decisions.!!! I love your cat, aluminum construction, smart and simple performance worked throughout the design.
You're welcome Dr Coole
Wow - Awesome boat . Thanks for the great video's.
Thanks Jevon...cheers
I love the simplicity, I love it doesn't have alot of stuff you don't need that will eventually break!
Cheers!! 🍻🍷
I agree Daniel.... We do sometimes get jealous of the "luxury" of other cruising cats....but i would not like to be in a serious seaway with a condocat.
Love especially the rudders...great common sense design. Cheers !
Yup... we accidently tested that design the other day... broke both shearpins when we hit a sand bank... fixed in about 2 mins.
Once again love your work and the boat
Cheers Evan...tks
Beautiful boat I can see why Plucky loves it
Simplicity is the ultimate sophistication 👍👍👍😬
Cheers Dennis
Love the the vid. Love the boat. Love you guys. Cheers.
Ha! Cheers Bob
You have a great boat looking forward to hear the pros and cons.
Cool...tks Bruce
Love videos like this
Cheers Walter
I'm amazed.
Cheers PC
I loved it. You dare to challenge the standards with light materials, and it did work. That´s how we evolve.
Tks Mauro, we love our boat.
I'm pretty Impressed with this boat, It seems too do it all
And there is only 2 of you
Defenetly the best boat I've seen on U tube
That’s a big call!….cheers Brian
Outstanding Catamaran. And your channel is excellent. Like your videos.
Cheers TMR... Appreciate it.
I really like the boat design. Everything is KIss. Plus it looks great.
Thanks Rothgar
Wow outstanding boat shes a ripper, love to own one one day and escape Australia, maybe even a Desert dweller like me could learn to sail the planet, inspiring!
Sure you can Kell... Cheers
I love watching your videos, I am sure that if I was going to get a boat then I would go with Aluminium first ! A Mumby Cyber 48 :)
Bewdy!... tks Reiri
Great episode
Tks man
yes please ! excellent video, found out about mumby from plucky
Hayden did he say that on his vids?
You are killing me mate, haha, I am a few months from ordering, now the waiting list will be the same time as a trip to Jupiter ! I am surprised it isn’t already ! Good boat and good review. 🙏
Cheers Tim
It is a fantastic boat. Anyone that has sailed on the ocean or owned a boat for a length of time, will appreciate the many design features of this boat... There are a few things I'd change. A larger salon and narrower side decks would be nice. Higher cabins so you can walk on deck, and grab a rail without crouching over and that would work well with more bridgedeck clearance. I'd gladlly take more bridgedeck clearance and take a hit on windage for that. Features I like the best. No holes in the deck except hatches--nice and dry. A dry boat is so much nicer than one with drips and leaks. The daggerboards are a fabulous design. These are personal nit picks. Overall I'd rate it one of the best designs I have seen. Congrats on a great boat. Its a good boat for a couple.
Thanks Conrad... Yeah everything is a compromise... But we love the design.
Excellent video.
Cheers Gordon
Great episode from Hamilton Scotland.👍🏴
Cheers William
The more I watch, the more I like this design
Awesome...tks Sid
love it 💕👍
Cheers bru!
Aye m8’s, excellent explanation on the design!
Thanks M8
Here I am again. This is really a nice boat.
Such a great explanatory video which puts it all to the point, simplicity!
Wanna put a down-payment on a Mumby 😀
My account number is.......!
Love this vid,love your Mumby,what a cat! Thanks for this walk around,just makes me want one even more. Now I know why Riley and Elayne are building one? I think.
Haha... I'm not sure about that... He was talking about big bucks!
I enjoy your explanations of the boat structure and design. Perhaps taking your time to fund the finalisation of the build allowed you to think things through very clearly. It is nice to see when a lot of thought has gone into something and that Mumby has an awful lot going for it. With the Outremer I find the trademark seats on the side deck an affectation that I wouldn't want to use on an ocean passage. I think the only addition I would make to Jupiter 2 would be to have a back up water maker. Nice videos. I enjoy them
Awesome...tks for the feedback David
Amazing, this design is really growing on me, love the functional simplicity of it. Keep the videos coming...
Thanks Mysterio...
Really great review love the mumby 48, it's my dream cat ,wish to have the money to own it one day, love from India.
Ah cheers Vipul
I have to share this info with my brother ! i am so Impressed with your narration of the Mumby Cat only an owner and experienced sailor such as yourself could do this boat justice.. I learned so much about your aluminum sailboat today and now i am left wondering how much does Mumby Cat cost...???? L.A Rob
Ah Cheers Rob... last weeks vid will answer that question!
ruclips.net/video/AH2XrdLi3jk/видео.html
Cool boat , I like the hinged rudder idea . My thoughts are to illuminate
the shears pins on rudders to magnets at the force required .
Yes, I love it
Greetings from Makati, looks like you are living the good life.
Tryin our hardest...Cheers Matthew
Lovely Cat 😻!!!
Tks JE
Hi, great points, looking forward to your views of the pros and cons. I was looking at a sea wind but came across your channel. Found I live 5 mins from the Mumby Australian branch. Liking the design more and more.
Ah bewdy Douger... Not sure where the Aussie "branch" is!? They used to build them at Monty's boatyard near Caboolture years ago... but not anymore.
@@SailingLifeonJupiter Probably Ben's yard up in Cairns...
@@somewhatodd1 ….No ….Harwood… Clarence river near Yamba.
@@douger1517 Tim hasn't used Harwood for building these things for a long long time. My boat was one of the last harwood boats (2011). That said, you probably could still get one built there.
@@somewhatodd1 …how about a review of your boat then.
Dammit man! You keep doing videos about your yacht and I am becoming more and more sold on its qualities. The problem is, there are almost none available! Guess I will have to keep watching for one while I look longingly at yours...
Yeah tru...sorry Dan!
Beautiful Cat mate. Cheers.
Thanks Jase
@@SailingLifeonJupiter your welcome.
👍🏼 nice cat
Cheers Latitude
i like that you can see the structure and simple is always the way to go. less has always been more to me. im a bike guy and my old 71 flh beats anything modern as i could fix anything that went wrong with it on the side of the road.
I think your parents are Tim Curry and Christopher Walken. Great Video !!
Just wish I could talk like Walken!
Hello! Liked and i'm your new Subscriber. Like your videos. Thanks for sharing!
Bewdy, thanks Jun
Your explanation has helped me make up my mind .. I want a Mumby !!
I love the almost idiot proof simple design and the easy redundancy of the boat ..
plus when you are on passage at night and come in contact with something the chances of a hull breach are if you favor on an aluminum hull - glass boats just can’t handle an impact..
plus the lightweight of the boat ..
so what’s the fastest passage you have made avg speed under sail ?
Keep the vlogs coming and I’ll keep watching. .. fair winds and safe travels
From west mid Georgia in the USA ..
Hi PO... Yep its a great design... It has been rare for us to get consistent weather on passage... our IO crossing was rough and wandering (for wind angle comfort) but reasonably quick 2400nm straight line in 12 days... We are happy if we avg 10kts...
Great presentation and such a brilliant design. I only sailed an aluminum design many years ago and it was noisy...is there any insulation or any other solution to this issue.
Pretty awesome design! Love the KISS theory. Looks very reliable and easy to service. Surely less weight will be good when you are looking for a haul out crane too?
It doesn't end up really helping with a haul out, as any travelift that can lift a boat this wide, will always be rated to lift much much higher loads.
Sure Michael... don't want that thing tipping over!
Very interesting boat and you and Princess are charming.I have sailed a little but I grew up next to a river in the American Midwest and have boated since I was a tyke! Lots of info for but the preventative measures needed. I,d be scared shitless about lightning!!! As to auto pilot you should get plans for a wind vane. Install one of those and you won,t use power to steer! One more thing,, that Beta marine engine doesn,t use electronics! Yanmar does. If the electronic controls malfunction your engines won,t run!!
Cheers
Tks for watching Laurie
😂 fantastic video 👍
Ah cheers Beard
I see this design as 95% in line with my preferences. Good review. You may want to list up the cons too - there may be a few :) Thanks
Yep Kobor... I'll be putting together a vid about the pro's and cons of ally boats soon.
@@SailingLifeonJupiter Yes, but you listed many pros, and skipped on the cons of Aluminium boats.
There will be cons as with everything else under the sun, but compared to most available production cats, common sense and functionality,the list will be short.
Ik moet zegen je heb wel gelijk
Utmerket.. Takk for at du så på
Great videos and smart presentation; really glad I found your site as it really makes you think. . You touch on a lot of obvious checkmarks in your video. What was the willingness of the shipyard manufacturer to make changes? Chines above the waterline to add passenger space without compromising performance - as an example? I don't think you mentioned gas for water heating and showers... but obviously gas is in the kitchen.
Thanks Edward... No the designer/builder has plenty of demand for this design.. He'll make small changes, but I suspect hull shape is not one of them.
Restyle the salon and cockpit with the pilot house windows and extended bimini hardtop like a lagoon or leopard and that's the perfect performance cruiser
But then it wouldn't perform!... everything is a compromise, unfortunately...Cheers Ronald
Super interested in this Design.. however I'd love to incorporate things like dual retractable outboards to further cut drag when sailing. And even retractable rudders for getting that minimal draft capabilities, and in a shtf of a rudder issue. Carry a spare that could just be dropped in. Additionally outboards are easier to service and replace. Even free lines if they get caught up
Wow really love the easy engine access and brilliant idea to cover the aluminum screen with polycarbonate in a gale. Only thing I can suggest is to put a hole in the aluminum screen so you can put your hand through and use the deadbolt and put the lock on the inside so that it cannot be cut off with bolt cutters
very interestning explanations , how to get the plan and where to let it build at reasonable price ? thank you very much
Hi and I think you missed the fact that the draft is much smaller with dagger boards retracted. More options when anchoring. André
True dat... i missed that one.
very well done! THX!!!
Great video jamie, really instructive and funny. Tim is going to hate you for bringing all this attention. It would really be very interesting if you could show the cockpit in detail so we can understand its positive and negative points. We almost never see it in the videos. It is really the only thing still stopping me from wanting a Mumby! Thanks so much for the work. It is very very enticing! Fair winds.
Yeah Antoine... The cockpit is very practical for sailing... Not so much for lounging.... I do get cockpit envy when lounging on condocats... But when out in the wild blue yonder, I appreciatethe Mumby.
@@SailingLifeonJupiter it would be great to get a tour. Cheers.
Great vid again. One question I have is weld quality. What do you reckon
I'm no expert on that Keith... but a German guy i met examining the yard and builds in Cebu told me that he is very impressed by the weld quality...and he comes from a family of shipbuilders... And I have faith that Tim Mumby doesn't let anything like that spoil his reputation.
best cat on the market for the money, and far beyond the price.
Cheers George
Dang, looks like I missed this video and this is the first time I've seen it. Onto part 4 I think.
Glad you found it.
hey I saw that..keep your hands out of that peanut jar lol! Bring galley up..bring galley down! Cheers big ears..have one for me! All you need now is a bandana that you can double as a mask when you need it and a parrot on your shoulder for that pirate look :-p Oh and where is the covid beard? But in all seriousness..it's a great design. I have always thought galley up but now tend to agree with you on galley down! Thanks for sharing & safe travels!!
I can't stand the itching!... Cheers SF
@@SailingLifeonJupiter Hear hear!
Jamie's dinghy is his "Man Cave!" Hey Jamie, nice video as usual. The Mumby design is very interesting - I'm a fan of performance oriented cats as opposed to charter boats - here in Southern California we call them pigs. One thing you haven't covered yet (that I've seen) is whether or not Tim included any sealed compartments filled with closed cell foam. It's very unusual for a large cruising cat to capsize, but if that should happen, you definitely want the boat to bob on the surface. Besides the beautiful lines and performance, the Mumby is incredibly inexpensive compared to other manufactures. Thanks for sharing your experiences, mate!
The Mumby 48s have a 4cm thick layer of foam between the inner and outer skin of the boat that insulates both noise and heat, while also giving about 4t of reserve buoyancy. In addition to that there are water tight compartments fore and aft in each hull.
@@somewhatodd1 Thanks for the info! Jamie showed photos of the foam, which has to be scraped down before the fiberglass skin is put on, but I didn't know if that was enough. Pretty interesting cat, huh?
Yeah Rick. The fore and aft compartments are airtight in theory and will keep us afloat... but it's a rare thing for a cruising cat to go over.
@@SailingLifeonJupiter That's good to know. It's very rare for a cruising multi to capsize, but it has happened. Always good to know that the boat will bob on the surface. Thanks Jamie!
its always pleasure wathcing your vidoes. i can see you guys are having a great time.
would you be kind enough to share the deatils around the Aluminium type/grade and thicknesses used in this catamaran?
Sure Zafar... Its 6083 and 4mm hulls and 3mm decks with plenty of stringers and stiffeners... Tks for the nice words!
Life on Jupiter thank you sharing this information. Have fun guys.
i love your boat mate. Let me ask you, how is the noise? water hitting the hull or metal to metal contact anywhere like doors or panels ? have any noise suppression? insulation in the hulls ?
Yeah Supersevenn, no problems with noise... I've put out a vid soon where you will hear the noise levels underway, since it is a common question.... there is 1" of foam on the hulls and decks to reduce noise/temp levels.
Excellent video Jamie. The pilot viewpoint of strategy, design, performance shines through.
Ah thanks for that UUBrahman
Really interesting daggar design, makes for a nice hand rail point too. It seems like there was a period from the early 90's upto the mid 2000's that saw a peak of alum cats being made and mostly in Australia. I suspect the massive deposits of bauxite there provide for some cheaper alum materials maybe? The Mumby is such a nice cat, my dream boat! There is a 13m Peter Kerr cat in Langkawi that I would love to get, unfortunately it's half way around the world from me and where I would like to berth her. Any skippers care to make the 12000nm cruise???
Ah, yes the Kerr design is a little similar... Sounds like a good shakedown sail!
off topic but ever thought about entering a ARC race?
Well...no plan to go to the Med at this stage... and from what i've heard, it costs big bucks...so not likely.
Awesome vid mate !! I have been involved with ally boat construction for the last 25 years , building ally commercial fishing , pleasure and government vessels , here in Geraldton Western Australia , I am interested in the construction of the hulls , what is the hull thickness ? Anyway I am an avid viewer of your channel and think your vids are great !! Stay safe and keep your vids coming :)
Oh cheers Doug... The hulls are 4mm and deck 3mm with lots of stringers.
Do you have experience with older ally boats? ie corrosion control, keeping paint on, etc?
Great vídeo. Thanks for sharing. What was the price?
Nowadays about $650k...new production line will soon be announced... If ur interested email me on Svjupiter2@gmail.com and
Few industrial catamaran are well made to travel. You didn’t talk about insolation I think such is very important on a aluminum boat.
Correct Eric... I show the insulation on the "Fitting out" video.
Plucky saw one somewhere, san blass i think, and he hasn't been himself since. A man smitten.
Hehe... Yeah, he wants one.
Don’t the dagger boards float up when tacking?
A bigger question for us is how much can a Mumby 48 hold? Enough for a family with kids to provision for a crossing?
I'm on a budget but I like this design. Do you think it's possible to buy just a hull and finish the electrical, furniture, appliances, engines, rigging, etc myself to save money?
Yep... I'm guessing about $120k usd... If you wanna get in touch with the designer/builder email me on Svjupiter2@gmail.com and I'll put you in touch.
I was always drawn towards monohulls because of their classical beauty, but now realize that this simple design is far more practical. Monohull keels appear to be a major repair and maintenance headache, also adding enormous weight. The only downside I can see with a cat is capsizing, but I assume there are ways to reduce sail area to avoid this.
For sure Dollarette... not very likely that cruising cats will go over....But you do have to actively sail them, and ensure that you're not overpowered.
Can you answer the big question of lightning strike risk. Being a conductive boat how much more likely are you to attract a strike v grp ? How do you protect yourself and crew (that would scare the hell out of me) also protecting the critical electrical equipment.
Enjoying you content .
Being a aluminum boat the electricity will pass through the hull straight to the water. No problem 😊
Good question Random.... I will do a vid soon about this, since it is a common question.... but in short... from my current understanding (haven't googled yet), you are far more protected in a METAL boat... you and your gear are in a giant "faradays cage", or a metal box used to protect sensitive electronic equipment from stray voltages or interference.... And i believe that a metal boat is less likely to attract a strike, since it conducts and equalizes any charge straight to the water..... whereas a GRP boat is an insulator and holds electric charges that build up... like a plastic comb after combing your (dry) hair.
At some point, the engines will need to be replaced. I believe I saw a overhead hatch in aft bedrooms. Are they large enough to hoist the engines out through?
Yep Paul.. Can use the boom with block and tackle to lift it out of the hatch...
Sorry if this question's been asked before but I was wondering how high your boat can point into a breeze
No worries DD, we can pinch up to 40, but to keep up the speed 45 off the apparent wind is more practical.
when i started building alu yachts in 85, alu was 4500 to 5000 tonne, it stayed like this til abt 5 years ago when it doubled in price, sure it is lighter than steel, grp, but too heavy for racing craft
it is very fast to cut, forget cut files, loft onto the plate and rip around with a saw, even quite sharp curves can be cut so accurately that no other things like grinders and sanders are needed, it fact prepping plates always use cutters or the abrasives from grinding will embed in the plate , welding three times the speed of steel, never tig seams or butts, all you get is massive distortion
Do you weigh what you put in the boat, when it’s overloaded how does it effect performance.
Nah Peter, i'm not that OCD... we got our whole lives onboard... The extra weight, just slows us down a knot or 2.
Hi guys where did u exactly manufacture your boat in the Philippines. I'm now in the Philippines. Thanks
Carmen, Cebu Marvin... small operation.
How does aluminium heat up in the tropical sun? What is a realistic price for a Mumby 48 ready to sail? Thanks for a short answer!
White deckpaint is a must, for any boat in the tropics... Market at the moment for newish used is about $450k usd....same as getting one built at Mumbys yard. Cheers Stefan
@@SailingLifeonJupiter Thanks mate! Still a bit much for my budget. But if you can sell for the same price, it looks like extremly attractive deal!
Can i get building plans ?
I did not know Diesel was still a thing. I used to be a Diesel guy during my youth in LA.
My clothes tend NOT to be "up to date"
In your crossing-preparedness checklist series you mention the importance of having a protocol in each case. What is your protocol in case of (God forbid) Jupiter2 tipping over? Your choice of the main door design in two pieces (the upper door being a metal grid runs contra to the principle of "keeping water out"), and the process involved in shutting 2 cockpit windows - only adds to my worries.
Will the sprayfoam and airtight compartments provide enough boyoancy to keep this boat afloat even in upside-down flooded position?
Thats the theory Garen... the designer made those calculations... Spray foam not relevant, but the buoyancy of the fore and aft compartments are. The cockpit doors will certainly let in some water... but they are far smaller and safer than the glass sliding doors of a lot of charter cats... and of course we wouldn't have the windows open in conditions where there is any risk of turning over.... which is a very very rare occurrence for cruising cats.
And we have the liferaft, just in case it doesn't float.
@@SailingLifeonJupiter yeah - those sliding doors in charter cats give me the chills; I guess they rely on their overweight clumsy designs as an advantage - LOL. In case of Mumby'48 I've read in forums that the foam that Tim uses has several properties and fulfils several functions: sound and heat insulation, anti-fire, aesthetics and buoyancy. Theoretically, a piece of 4mm aluminium plate with 4cm foam attached certainly wouldn't sink. I've seen a heavily modified Mumby'48 self-build with 2 escape hatches near the stairs. Although, it's in CE regulations, the safety of the escape-hatches is debatable - once you open them, there goes whatever air that was trapped in the hulls. Still, the open plan layout should make it relatively easy to swim out of the main door, no?