My little piece of peace

[Frosty]

All ive ever had is domestic on a few boats now.

Invertors are sensative little buggers and choosing one carefully to fit its demand is important. I have one that I bought in Aus it was great till I blew it and had it repaired in Taiwan for free ( I connected it into the 240V supply,my fault entirely) .

Motors like full sine and I start my fridges up one at a time after starting at least one engine. It has accidentally handled the kettle as well (1200wat) and the toaster. These kinda things don't care about sine waves.

There is no point having a 2 kw inverter running a computer. You can buy tiny ones very cheaply, this is ideal for lap tops and Cmap.

I would not synchronize them but diversify there obligations.

By the way dont bother buying a small 12inch 12 V Tv I did and it broke, it was expensive too. The repair man says it the inverer gone. Its just a TV with a small inverter inside. It continued to work on 240 V ok, what a rip off.

Just buy any Tv you want and use an inverter



Doing it this way means you dont have to run huge Dc cables to run one. A small 300w invertor will use a much smaller cable.

If you going Invertor and domestic it might be a good idea to think about cable runs and appliance position in your design.

My invertor simply lives near the batteries and I put the 240 volt straight into the ring main, of course I have to go and check the kettle and toaster etc is unplugged first,even then the invertor is protected and will bleep indicating too much load. Good ones are good.

Its all down to familiarity of your equipment, this is the missuses job actually.

[masalai]

Mondays effort is being uploaded as I type... Bryan threw a "spanner in the works", in suggesting that I consider mini-keels and thence fixed rudders instead of centreboard & kick-up rudders - seems like a good idea, quicker and easier build and easier on beaching for bottom cleaning... I think draft goes up from 400 to about 750mm - I will check with Bob Oram if this can be done and is acceptable... For news and developments watch this thread

[Manie B]

As you know i am a huge fan of 40ft cruising cats, and over the past 5 years i have done an endless amount of study on this subject. There is a massive amount of info available that speaks of the ease and efficiency of mini keels. Many "Easy" cats were built that way with great success, they sail well and definately no problems. And as you know their resale values in OZ has remained high.

There were some "Woods" designs built here locally with mini keels that i have sailed on with no real problems, unfortunately they were built so poorly at that time that it actually wants to make you cry. So the boats dont get sailed hard, they are lousy weekend condo's.

I favour mini keels for short handed cruising, they are strong. I am working my bum of on my lifting centreboard and bulb keel - and casing. It is a frightening amount of work.

[RickEdmonds]

Just stumbled across this thread - Mas I'm very interested in your idea of using the Torqueedo's. I'm building a slightly smaller cat but would love to have a diesel generator that also drives a eutectic compressor, with twin (liftable) electric drives. I'll follow your progress with interest.

In a former life I was an electronics expert. I noticed your concept of using copper water pipe to get greater surface area of the conductor, but that doesn't work for DC. DC and low frequency stimulates the electrons deeper into the conductor - as frequency rises (VHF and up), the surface effect you speak of kicks in.

Welding cables are many stranded, but that's for flexibility. If you can find a suitably rated multistrand semi-rigid cable, that should give the lowest losses.

Best

Rick

[masalai]

Manie, did you see the "30ft cat for $21,000" in the coastal passage? http://www.thecoastalpassage.com/recent_issues.html #37 - or here - http://www.thecoastalpassage.com/cheapcat.html - - - no plans, just marine ply and 'that looks OK' plan...

Those pics have a lot of fat in the underwater bums? - (at least the white one) The Easy 'in the sky' looks OK?

RickEdmonds, Thanks for the comment, - - - go and have a look at the "Scrumble Project" - Follow my link for Bob Oram Designs and also visit in Darwin where their build is... Thanks for the guidance - I can get cable OK, just the expense... Copper pipe with the "insulation" used for plumbing hot water and by flattening the ends had a ready busbar from the genset forward of the mast to the batteries and motors aft (not to carry water, just lateral thought and convenience?)...

The Torqeedo is imported by Claude, who is the Australian distributor... He lives up behind Noosa not far from my home... They lack in reverse power, as the propeller is optimised for forward efficiency & perfectly matched to the electric engine... I understand that there is an engine being tested at 'Sanctuary Cove' running full throttle 24/7 since the boat show there mid May 09... http://www.torqeedoaustralia.com/Tor...alia/Home.html Have a real good look around as there is lots of stuff on the "4.0R Cruise" and in the other international links... I like it, and am quite comfortable with the prospect of using it on my boat...

I have gone for maximising electrical capacity of the genset and using inverters and high efficiency "domestic 240v vertical freezers with plastic drawers" and de-rating to use as a fridge, with an external high accuracy thermostat to supply power at the plug (so no modification) - LG (GC154-SQS) from "Hervey Norman" for AU$450 with 154Liters volume - beats anything else hands down... I am installing an all electric (NO GAS) galley...

[masalai]

Still in the early fitting out stage with bulkheads and doorways being sorted... The router with the fitting as in 'image 3' does a neat job of removing the balse as in 'image 2'... 'Image 4' shows the doorway reinforced and balsa sealed ready for painting or installing a door... 'Image 1' is a double berth space ready for base upon which to place the innerspring mattress...

[masalai]

Seems a second post to add extra images? (beyond 5), No visible changes of the bows (just to reassure you that at least half is still there) and a view under the bridgedeck with reinforcing girder (doubles as cabling duct etc.) and new supply of mixing buckets and used ones full of rubbish for disposal, then 2 different views of the starboard stern section - my coffee mug marks where the rudder post will be - approximately.... Foreground of 'image 1' is 2 booms made up and ready for fitting on 2 other yachts (44C Orams)...

[Fanie]

Looking good Mas. And thanks for the pics, I save them.

Somewhere in the distant future (if something like that exists) they can look at your boat pictures and and marvel at the slow and primitive building method not to mention the hard labour that went into it

I'm building a small layup machine on the moment to do just that. If it works a perceived one would be able to layup a hull in a day It should have a good resin to mat ratio and one or two person's only. We'll see.

I was on the second largest sailing cat in SA last week in Richards Bay... it's a monster of a boat. Slightly large for me. If you look for someone you have to walk around to find them, and it's much further to the head

[Manie B]

Mas another very interesting item for your "domestic" appliances are fans, the guys swear by them, apparently the 12v hella that are good have become expensive, and i just bought a small desk top 300 dia 220v el cheapo - it is VERY QUIET at low (#1) speed and moves a good an mount of air, so yeah me too invertor and domestic

mine is just a micro mini extra teeny weeny system like yours that runs of unleaded

[Manie B]

Hi guys here is a question for all you electrically minded lot out there

If i run my 900w 220v microwave for 10 minutes - thru a 2000w invertor fed by 2 x 12v 100 Ah deep cycle batteries - how long do i have to run a 50a 12v automotive alternator with built in regulator to recharge the batteries to full again. I am told that the alternator is fine at 2500 rpm because the exciter coil is fed????

Please dont get carried away with milliseconds and and ball park figures for an old fart

next stooopid question

if i run 2 x 1000w invertors parallel can i draw or use it as 2000w
this is instead of 1 x 2000w invertor
redundancy and all that keep 1x 1000w spare?

thanks guys - tomorrow is friday - nice boat building weekend ahead - and if i find suitable crew i will post it to brighten up your day

[Fanie]

You cannot parallel inverters unless they are synchrinised, so the answer is NO, you cannot parallel them.

A big microwave uses the same energy as a small one to cook the same thing,
the big one just does it quicker.

A 1000W inverter is going to draw 100Amp from your 12V battery.
You can hence run it for an hour off a 110Ah battery max if it is fully charged, although it would probably be less.

You cannot charge the battery at 50A for 2 hours to fill it back up, the battery needs time to fill back up to full. Thumb suck you need to charge the battery AT LEAST for 8 hours, limiting the charge voltage.

You shorten the battery life considerably when you deplete it completely. Best to get some kind of life from the battery is to use as little of it's capacity at a time and charge it back directly after use.

The best option to run a microwave is to use a mains generator that can power the microwave for the time it is in use.

[Boston]

looks great Mass
way to go

hey what color
gold?
har har har
ok bad joke but I just got in from work and my brain isnt back on straight yet
was sunny and hot today and I had to give a lecture
so Im beet
the boat is looking great though
thanks for posting all the pictures and also for the info on the electronics

[Fanie]

GOLD !! Don't be surprised. Expect to see an upside down US flag on it as well

[Landlubber]

Fanie, From "down under", the flag is already upside down.....

[masalai]

Oooooh that is code for distress and I am not in the least distressed... and to agree with Landlubber, is surely an indication of the state of USA?