Biggest test of the MTS255S so far

[Jim Davey]

If a big wave knocks your average commercial monohull fishing boat over, if the doors are shut there is a good chance it will come back up due to the weight of the engine and fuel low down in the hull and the air trapped in the cabin spaces. But catamarans almost never roll back right side up. On the other hand it takes more to tip one in the first place.

 

[Hood]

I never got to go out of harbour with the cats we we playing on so can't speak to the feeling in true waves. You can clip them along at a vast rate of knots though!

One that's always intrigued me to have a go in is a wave cutting design. I just can't get my head around not wanting to ride the wave but just cutting through it. Bananas.

Is that the type of racing yacht they are moving to now? the ones that basically ride on wings?

Cats won't self right either, if they roll over, they tend to stay rolled.

If you roll one of these Cheetah cats you are in extremely severe weather that you definitely shouldn't be in. Regarding fishing boats I have never seen one that would come close to self righting, even most the RNLI boats require air bags being deployed to self right.

 

[daleyd]

If a big wave knocks your average commercial monohull fishing boat over, if the doors are shut there is a good chance it will come back up due to the weight of the engine and fuel low down in the hull and the air trapped in the cabin spaces. But catamarans almost never roll back right side up. On the other hand it takes more to tip one in the first place.

If a boat goes over they generally don't come back. With good design some can go a fair way and come back but that's not the same as self righting.

 

[Hood]

I have also spent some time as a fisherman (10 years) it took me 9.5 years to realise that I shouldn't of done it. But it was theraputic, It forced me to get off my **** and do something. Instead of going to the pub in bad weather I went to fix boats and as a result got quite good at it. This has put me where I am now. If only I was just a bit smarter I could find something easier to do
Oh well there is no such thing as a perfect job
I forgot, I had a round bilge boat (Tassi cray boat) made from Cerery Top Pine it could roll the milk out of your coffee.

Sounds very close to the way things happened for me, still sometimes miss the sea then I think how cold, wet an wild the North Sea can be and I know I made the right choice.

 

[Jim Davey]

I'm not talking about self righting, I'm talking about the tendency to get rolled over by one big wave, and then turned over again to end rightside up by the next.
Due to the extra beam of a cat they don't tend to allow themselves to be flipped back up but this isn't really a major concern for vessels fishing coastal waters.

 

[Hood]

I'm not talking about self righting, I'm talking about the tendency to get rolled over by one big wave, and then turned over again to end rightside up by the next.
Due to the extra beam of a cat they don't tend to allow themselves to be flipped back up but this isn't really a major concern for vessels fishing coastal waters.

Problem is waves tend to come in 3's

Think we are talking different class of vessels.

 

[eSCHEn]

Is that the type of racing yacht they are moving to now? the ones that basically ride on wings?

No idea really, it's been a few decades since I last raced competitively

This is similar to what I had a play with then only newer and not in disrepair :

Not the best image (most seem to be trimarans) but this is the wave cutter design I mentioned:

 

[Hood]

Ah ok I see what you are meaning now, kind of going back to the old fashioned look design but brought a bit more up to date.
The first type was what I thought you were talking about but the ones I saw were monster things, doing the ocean racing and very impressive vessels. A boat to me is a workhorse, for fishing, never really fancied being a WAFI

 

[Hood]

This was what I was talking about, wouldn't mind a wee trip in it to be honest.

 

[eSCHEn]

Lol, nor me I just like going fast

Aye the big ones look crazy fun

Edit: ditto mate, looks amazing even with silly Oracle stickers (boo hiss!)

 

[arther dailey]

thats not a boat,more some sort of UFO...

 

[Hood]

Well this wee inverter continues to impress me. Was doing the first part of the roller system for the second Cheetah today and although mostly measuring and designing I did do a small amount of welding. 8mm thick 5083, with 24v and wire feed at 12m/min with 1mm 5356 wire and it just ploughed into the Alu. Think I will have to go up to 1.2mm wire as it seems to be getting a bit too much for the 1mm wire, only problem is the roller in the spool gun only has a 1mm groove so not sure how it will feed. Can always use the bigger spool gun off the Esab although I do prefer this one now I have adapted it for the swan neck.
Had my step brother look at the current readout whilst I was welding and it was averaging about 190Amps so still a fair bit off the max 250Amps of the MTS.

Anyway a couple of snaps of the welds, not the neatest but....

 

[Jim Davey]

I'd stick with the 1.0mm on a 250. It tends to be a bit more forgiving, especially when you go back to the thinner sections. Nice results though, I've got some ally welding to do before the weekend, looking forward to getting my hand back in, it's been a while.

 

[Hood]

Prior to getting the MTS I nearly always used 1.2mm, granted this was on the 450Amp Esab but even still I would be using it for 4mm and up and I actually prefer it to the 1mm. Probably just because it is what I have used more often than 1mm wire. Will see how it goes with the 1.2mm, nothing to lose as I have about 15-20 rolls on the shelf so might as well try it out on this heavier Alu and see how the MTS handles it.

 

[Hood]

Good pic showing the difference between the old 6.9m Cheetah Cats and the newer ones.

 

[Hood]

Did a bit of welding with the 1.2mm wire and it went well except I had forgotten to take the 1.4tips so the wire was sticking a bit as the heat built up. Had to lower the wire feed quite a bit, not sure but think around 9.5 to 10 compared to the 12m/min for the 1mm wire.
Went well, first pic is a vertical up weld, second is showing the penetration on a but weld on 8mm thick 5083 with a 2mm gap before I ground and welded from the other side.
This pic is the side plates I cut on the plasma before I headed up to start on the roller system and lastly a couple of pics of the progress so far.
Loving the MTS and only thing that could make it nicer would be if it was a pulse Mig

 

[steve t]

do all those cheetas have outboards or do they do an inboard diesel one?

 

[Hood]

Any I have seen are outboards.
The Fishermen seem to like them for a few reasons, one is they are not that expensive to run as they get all the duty back on the petrol so it is only costing around about 35p/litre. Another is that if there is a problem with an engine it can be removed and replaced with another the same day, no weeks of fishing lost like you can have with an inboard. In fact months can be lost with in boards as I have seen wait times for some engines of 8 weeks or more. Another is they replace the engines every 3 years or so and from what they have said they get excellent trade in price for the old ones, go much more than 3 years and they get a very poor trade in price.
Another consideration for them is the initial cost of the licence, it goes on KW, so if they have inboards they usually need quite a bit more power than they do with outboards. Think Licences are currently about £250 plus VAT a KW at the moment so it is a fair chunk of money.

One downside is there is no pier side petrol tanks so they have to get the tanks filled at a filling station and carry them to the boat but even that is not too much hassle.

 

[Hood]

Roller system starting to take shape, next job is to make vertical rollers for the sides and to make an angled deflector on the bow side. Then it will be onto the hauling table and hauler mounts.
One thing you learn when doing boats, they are never straightforward as even bits that seem flat and true are the polar opposite

 

[Hood]

Also had to go back to the 1mm wire. Took up some 1.4mm contact tips today but the wire was still feeding unevenly at times. I had thought it was the heat expanding things and making the wire stick in the tip but it looks like it is the roller being a 1mm groove that is the issue, will have to turn myself a new roller with a 1.2mm groove at some point in the future.