Billy2014

Boat Build - CNC Marine Platey

25 posts in this topic

Hi Everyone,

I'm new here but it looks like the place to be.

To anyone that may be interested or ever thought of attempting this themselves, I have just finished a home made plate boat.

http://billsboatbuild.blogspot.com.au/

The blog dates back about 12 months or so, right to the beginning.

Cheers,

Bill.

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impressive build what kind of CIG Weld mig is that? i noticed u mentioned using wire and rods what parts did u have to TIG? i taught my self pretty quickly how to tig steel but aluminuim in 1.6mm is a bloody nightmare although i can TIG 3mm ok

i like your fuel tank breather idea

how many bottles of argon did it take?

i was looking at going down this path months ago but couldnt justify the prices of the precut kits they arnt much cheaper than a commercially built boat which is a downside

still looking thru your build diary :)

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G'day Gazza,

I used a Cigweld 250i professional single phase MIG with a euro fitting push-pull gun, great for aluminium, smooth 1.2mm 5356 wire feeding. The TIG is a Cigweld AC/DC pulse TIG 200amp machine, really nice, single phase so not a pro version. The MIG was good for most stuff but for the finer welds and repairs I found the TIG much easier to use, the MIG gun is just really quick and can fit in almost anywhere.

Aluminum just needs so much more heat so things can get out of hand very quickly, not sure what electrodes you are using for TIG but 1.5mm should be good on a very low amp setting using a 1.6mm electrode (2% lanthanted) sharpended and 5356 1.6mm rod, and if you have pulse which helps control heat input (not essential) and also pump up the AC frequency, I think it's just trial and error. I have successfully welded an aluminium can together so anything is possible.

For the build I used 2 x G size bottles and I think 4 x E size, Supagas is the cheapest here in Sydney and good service. Now that I have an addiction to welding, I am just keeping a small bottle of argon handy all the time, D size I think.

Home building is by no means for anyone, its really hard work and my space was extremely limited. I did look long and hard for a commercially built plate boat but when I compared apples to apples, the commercially built boats ended up about 5k more even after welders, tools and consumables were taken into account. Aluminium has dropped in price too, kits a a fair bit cheaper now. The other driver for going DIY was that I could do things in stages as funds would allow, as it turned out I got it done pretty quickly in the end, once you see the thing start to take shape it gets very exciting!

I would suggest to anyone that they have decent carpentry skills and tools, lots of building space and a good bit of time, it's a very satisfying feeling being on the water with a boat you made yourself. The really hard bit which is the 1/2 kilometer of cutting is already done for you so these pre-cut CNC kits are excellent.

Cheers,

Bill.

Edited by Billy2014

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thats really good work.

Were you a welder before you started?

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G'day Antony,

Thanks - No, I had no idea but I like to learn new stuff and did a lot of research and practiced beforehand on lots of scrap, probably spent 6 months practicing before I touched the boat. Had a few 'old timers' give me

some priceless advice as well.

Had to refine technique and equipment first and also tested the welds until they wouldn't break, even under my steel sledge hammer :biggrinthumb: Once I was happy that my two sided welds

could withstand being T boned by a harbour ferry I decided to start on the boat kit.

Cheers,

Bill.

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bill, on your chines i think i seen u write "mig" "tig" "mig" was that part of the building process or could u have just ran the mig right along the whole seem?

and the big Q how much did it set u back to build the hull?

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bill, on your chines i think i seen u write "mig" "tig" "mig" was that part of the building process or could u have just ran the mig right along the whole seem?

and the big Q how much did it set u back to build the hull?

G'day Gazza.

Yeah - What I tried to do was run a MIG bead, usually 100-150mm long to avoid too much heat build up in one place. Beads have to be staggered, sequenced, front port, rear starboard, rear port, front. starboard, centre port and so on and so on. So many opinions on staggering sequencing so I won't go into it. Main thing is to make sure to never weld in one area for too long or the boat could twist and be a write off, aluminium can and will twist easily under heat and be very hard to recover from. Back to your question, once the MIG beads are all run I left small gaps so I could run a TIG bead, reason being is that MIG isn't great at start and stops and starts are where you get poor penetration, stops sometimes have craters. Yes, there are ways around this too with good technique, pre-heating etc and MIG is perfectly fine but I would suggest using a carbide tipped burring bit to drill out MIG starts and stops, remove the potentially bad bits before you finally join the beads up. At the end of the day, all you want is a water-tiight hull and welds with good fusion all the way through, not just the middle bit of the bead. TIG on the other hand allows you to control heat input much better, you can melt-in the existing MIG start or stop so you get a nice and smooth transition.

With the cost of both my welders, gas, rods and wire consumables, the entire hull build was 15k, I can now sell the MIG and recover some money or sell both TIG & MIG- For smaller plate hulls they were quoting me 18k plus this and plus that so it was out of my budget. "Oh you want it like this do you, 700MM sides, built-in catch tank, custom canopy? That will be another $5000 thank you". I guess if I lived in QLD or WA things could be different, I am sure there are builders out there that I don't know about. Also, welders were asking for $100/ hr to weld the kit for me! How much time it would take is a pretty big unknown unless they do that sort of stuff all the time. Also, my canopy is very custom, the entire boat can fit into a 2.1m high carpark, that sort of customisation is difficult unless you can do stuff yourself so the welding experience I now have probably out-weighs the fish I didn't get to catch last year, maybe... :-D

Cheers,

Bill.

Edited by Billy2014

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thats a dream boat if including the two welding machines and all consumables for 15K , i was looking at much smaller 4.2/4.5 CC's and they were something around the $9000 mark as a kit no welders or anything so i couldnt justify the price and im now building a composite boat instead

are u going to paint your new boat?

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thats a dream boat if including the two welding machines and all consumables for 15K , i was looking at much smaller 4.2/4.5 CC's and they were something around the $9000 mark as a kit no welders or anything so i couldnt justify the price and im now building a composite boat instead

are u going to paint your new boat?

I am pretty sure the 5.0m kit from CNC Marine is 8K out of WA at the moment - Worth it for sure if you want to go this way. It helps if you already own tools too, you would need a fair few tools like good quality grinders, drop saws, clamps and the like.

I don't think I will paint it, it will just dull up and the sanding marks will fade - I have already grazed the sides of jetty's a few times courtesy of the river cat and it's annoying 3ft high wake, if she were painted it would need re-painting now, just less to worry about with the industrial finish I think.

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thats a dream boat if including the two welding machines and all consumables for 15K , i was looking at much smaller 4.2/4.5 CC's and they were something around the $9000 mark as a kit no welders or anything so i couldnt justify the price and im now building a composite boat instead

are u going to paint your new boat?

I am pretty sure the 5.0m kit from CNC Marine is 8K out of WA at the moment - Worth it for sure if you want to go this way. It helps if you already own tools too, you would need a fair few tools like good quality grinders, drop saws, clamps and the like.

I don't think I will paint it, it will just dull up and the sanding marks will fade - I have already grazed the sides of jetty's a few times courtesy of the river cat and it's annoying 3ft high wake, if she were painted it would need re-painting now, just less to worry about with the industrial finish I think.

what fee's do u have to pay, cutting files and plans + material cost + delivery? is there any bending required the type u need shops to bend or are all parts pre bent?

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what fee's do u have to pay, cutting files and plans + material cost + delivery? is there any bending required the type u need shops to bend or are all parts pre bent?

The 8k is for one kit, pdf & hardcopy plans, builders plates plus delivery, cutting files are usually CAD files that can be sent to people like onesteel for cutting with their CNC machines - Bending can be done yourself if you have access to equipment, seeing the plate is 5083 structural grade plate, you need some pretty serious machines, I paid a few dollars per bend, got a fabricator to do it for me. There are other kits that have some tube parts pre-bent but then the sides of the boat are only 550mm high, priorities I guess, there is always a compromise or catch somewhere. CNC Marine kits have no pre-bent parts, all pipe bending is by the owner, all kits would require bending of flat parts though, some people don't even bother bending, they just cut and weld the corners of everything, bent corners are pretty nice though using a 1" dia rod as a die. 1" will also ensure that the harder 5083 aluminum won't crack when bent, higher tensile strength material means a larger bend radius is required.

Edited by Billy2014

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I have decided to pin this topic as there is some great info for would be builders.

Very nice work Billy and welcome to the site.

Regards Admin

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thats a dream boat if including the two welding machines and all consumables for 15K , i was looking at much smaller 4.2/4.5 CC's and they were something around the $9000 mark as a kit no welders or anything so i couldnt justify the price and im now building a composite boat instead

are u going to paint your new boat?

Hi Gazza,

What sort of composite boat are you building?

Glass?

Cheers,

Bill.

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Hi Gazza,

Mate, that looks amazing! I am very impressed and wouldn't mind trying that sometime myself, it will be a very strong boat.

Nice design too, I will be following your progress :-)

Are you definitely planning on building an aluminium trailer? I've thought about this too, was just a little concerned about the structural side of things and getting it registered.

Cheers,

Bill.

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Bill i have been sending emails back and forth to a company in sydney who bends metals and the aluminium i beam is heat treated to T6 so the company i found is unable to bend it so i wont be building the aluminium trailer unfortunately would have loved one tho they are a little pricey still to buy one already made so im going to have to go with a galvanized trailer

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Bill i have been sending emails back and forth to a company in sydney who bends metals and the aluminium i beam is heat treated to T6 so the company i found is unable to bend it so i wont be building the aluminium trailer unfortunately would have loved one tho they are a little pricey still to buy one already made so im going to have to go with a galvanized trailer

Nothing wrong with a decent galvanised trailer.

I don't think T6 is bendable without weakening it so I am guessing the commercially made aluminium trailers aren't using T6 members either where they are bending.

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Nothing wrong with a decent galvanised trailer.

I don't think T6 is bendable without weakening it so I am guessing the commercially made aluminium trailers aren't using T6 members either where they are bending.

theirs a slight catch when buying the main trailer rails i can order any grade aluminium i like with which ever treatment but i need to buy minimum 250kg worth otherwise im limited to 6082 T6 i beams its a shame i had my heart set on building a bolt together aluminium trailer

the i beams weigh 27kg each so i'd need to buy a few to make 250kg

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theirs a slight catch when buying the main trailer rails i can order any grade aluminium i like with which ever treatment but i need to buy minimum 250kg worth otherwise im limited to 6082 T6 i beams its a shame i had my heart set on building a bolt together aluminium trailer

the i beams weigh 27kg each so i'd need to buy a few to make 250kg

Which members are meant to be curved, main frames? I know the cross frames are good if they are curved to get the keel rollers down. do you have a design? Can the main frames or A frame be welded?

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Which members are meant to be curved, main frames? I know the cross frames are good if they are curved to get the keel rollers down. do you have a design? Can the main frames or A frame be welded?

i probably could have the A frame welded but i dont know how good it would be mate it would be cheaper than what i was quoted to get it bent or rolled @ $560 actually i may look into it but i think the i beam would need to be boxed in once welded, i have a local aluminium specialist welder i use and their great at what they do so i might send them an email

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i probably could have the A frame welded but i dont know how good it would be mate it would be cheaper than what i was quoted to get it bent or rolled @ $560 actually i may look into it but i think the i beam would need to be boxed in once welded, i have a local aluminium specialist welder i use and their great at what they do so i might send them an email

T6 is structural, builders scaffolding is usually T6 tubing and they weld those. Weld T6 with 5356 filler and it will be very strong providing joint design is right. I saw a trailer under a new Yellowfin boat, it was a hybrid aluminium and galvanised steel design. Most of the members apart from the running gear are aluminium and the forward frame was galvanised steel all bolted together. That's how I remember it, took a photo of it I think, somewhere....

Edited by Billy2014

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T6 is structural, builders scaffolding is usually T6 tubing and they weld those. Weld T6 with 5356 filler and it will be very strong providing joint design is right. I saw a trailer under a new Yellowfin boat, it was a hybrid aluminium and galvanised steel design. Most of the members apart from the running gear are aluminium and the forward frame was galvanised steel all bolted together. That's how I remember it, took a photo of it I think, somewhere....

that is a pretty easy option using the gal steel and aluminium cross member, do u know how the A frame was bolted to the drawbar?

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that is a pretty easy option using the gal steel and aluminium cross member, do u know how the A frame was bolted to the drawbar?

No mate, the trailers are made in the Telwater factory I think. I saw them down in Nowra at one of the main dealers down there.

I tried looking for some photos of them but the website pics are very small. From memory though it looked very simple bolted up. If I am not mistaken, I think the A frame and draw bar are all galv steel then the main frames were aluminium but don't quote me on that one. It would kind of make sense too, no curving of aluminium T6 required and the bits of the trailer that spend more time in contact with salt water are aluminium.

Got me curious now, wish I had a Yellowfin dealer close by!

Edited by Billy2014

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Finally your pride and joy is complete Bill. Well done mate :-) Welcome to fishraider.

I bet you're one proud owner and why wouldn't you be. The satisfaction of building your own boat which works and caters your needs is priceless. You just had to rig her up for some bluewater fishing ay? Maybe a little late for the beakies but when the tuna start moving we have to take both boats out. Btw Love the outriggers have you tested them yet?

Regards

Vic

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Hey Vic,

I hope you got out during your holidays, weather was pretty good. Yeah, too late for beakies now, you would have to work a lot harder for them.

I still haven't tested the riggers yet but I am almost done with the gamefish gear, tying doubles, teaser is nearly done

so I will be pretty keen to get out and fine tune it all over winter and hopefully fine tune it on some tuna as well!

Going out with two boats sounds like a great idea so I am definitely looking forward to that! It's been a long while but I am guessing, August, September, October for the yellowfin.

Last Yellowfin I caught was cubing off Browns, last century, August 1995, haven't been out for fin since, small fin but what amazing memories!

Cheers,

Bill.

post-33700-0-68131800-1398373502_thumb.jpg

Edited by Billy2014

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