Advice for rear casting deck

[Thunderace]

G'day, first time poster here, I'm currently finishing off the fit out of a old 4.2m stacer runabout with sounder, lights, storage etc.
I would like to install a rear casting deck


In the photo the two pods have cushion seats on them, and as you can see the left hand one contains the battery
My thoughts are to make a Aluminium frame with Ply/carpeted and access hatches, this would be bolted in so it would be easiely removable.
-It would sit onto of the pods and mount at 4 points at the transom, 2 at either end and 2 near the motor
-The yellow rectangles would be acess hatches, 2 for the pods, the one on the left for general storage, the one on the right, for a livewell
If got a few question I hope people that have done similar work could help with
1) I was planning using Aluminium RHS, what section ????
2) How thick plywood ???
3) Is there any issues putting a Live well in the corner, should be 60-70litres
4)For the hatch on the top left, what is the best way to support the closed lid

Floorplan, hatch positions


Thanks for any help


Stuart

[leachy]

Hi Thunderace

Looks like a good project. I to am building platforms for a Allycraft 395 Shadow. Are you going to weld or rivet and silastic the aluminium sub frame to the existing structure. I believe that the going thickness is 19mm for this type of deck.

Regards
Leachy

[spoonta66]

I would stay away from finishing anything on a deck with cushion seats unless they are the fold down type. You can, and eventually will, trip over anything sitting proud of the deck as you are fishing it.

[Gudgeon]

Hi Thunderace

I made a rear platform for my boat with aluminum square section you can get from Bunnings. It's used to make custom-sized shelving units and uses plastic joiners (tee's, crosses etc), is anodized, and reasonably priced. I glued and stainless screwed the joins for extra strength.
On top of this I placed 15mm structural ply, coated in a clear marine-grade urethane varnish and then marine carpet, for the floor of the platform. I screwed this ply down onto the frame for extra stength. All-up about $100 I think.

The whole platform comes out of the boat as needed, and easily takes the weight of my 120kg mate. If I get 10-15years from it I'll be happy.

[Thunderace]

Originally Posted by spoonta66

I would stay away from finishing anything on a deck with cushion seats unless they are the fold down type. You can, and eventually will, trip over anything sitting proud of the deck as you are fishing it.

Will just be carpet on deck
ta

[Thunderace]

Originally Posted by leachy

Hi Thunderace

Looks like a good project. I to am building platforms for a Allycraft 395 Shadow. Are you going to weld or rivet and silastic the aluminium sub frame to the existing structure. I believe that the going thickness is 19mm for this type of deck.

Regards
Leachy

i plan on having the deck removable , I''m thinking that the mounting at the back will stop it moving around, but allow me to flip it up

[Dror]

I have always used 13mm ply for my decks. Just make sure you have a good support framework under it. Much better weight savings to add 1 or 2 extra cross pieces than to use thicker ply. 19mm ply is heavy and in a small boat you want to keep the weight down if possible.
Personally I would not put a livewell at the very side of a boat that size. It will put things out of balance and because it is not always full you will have a varying list on that side. Ideally heavy items are best located in the centre line of the boat so that they do not detract from the stability.

Cheers, Dror

[Thunderace]

Originally Posted by Gudgeon

Hi Thunderace

I made a rear platform for my boat with aluminum square section you can get from Bunnings. It's used to make custom-sized shelving units and uses plastic joiners (tee's, crosses etc), is anodized, and reasonably priced. I glued and stainless screwed the joins for extra strength.
On top of this I placed 15mm structural ply, coated in a clear marine-grade urethane varnish and then marine carpet, for the floor of the platform. I screwed this ply down onto the frame for extra stength. All-up about $100 I think.

The whole platform comes out of the boat as needed, and easily takes the weight of my 120kg mate. If I get 10-15years from it I'll be happy.

I've started on this 50*25*2.5 mm for the beams across the seat pods and 25*25*3 for the rest, the frame will be mig welded.
The aluminium is 6.5kg, and 15mm ply will be 13.5kg plus carpet
I'm not sure how I'll attach the the ply/carpet to the aluminium, maybe screw from underneath

Alumiunium ready for welding


Plan for the doors

[Thunderace]

Originally Posted by Dror

I have always used 13mm ply for my decks. Just make sure you have a good support framework under it. Much better weight savings to add 1 or 2 extra cross pieces than to use thicker ply. 19mm ply is heavy and in a small boat you want to keep the weight down if possible.
Personally I would not put a livewell at the very side of a boat that size. It will put things out of balance and because it is not always full you will have a varying list on that side. Ideally heavy items are best located in the centre line of the boat so that they do not detract from the stability.

Cheers, Dror

true, I haven't brought the ply yet, but was planning on 15mm, I wanted to keep the doors at the back as big as possible, so I might have to brace on the back of the doors, will see how i go
With regards to the live well, its about 50 litres and with my weight of 72kg, its not a issue, it maybe get moved to between the two seat pods or my better idea is to replace the two front swivel seats with a bench seat and a livewell underneath

[Mooza81]

Make sure you take your fuel tank out before striking an arc... Otherwise the cast platform will be the least of your worries.

[Thunderace]

Work So far

Frame TIG welded up

Ply cut out, ply also had a small chamfer on both sides of edges

Hinges added, holes drilled, Ply now ready for sealing
Total weigth so far is 17kg

[stacer420]

Looking good mate, nice neat job so far. It is going to be a neat and tidy fishing platform when you get it finished, Plus you will have the satisfaction of setting it up yourself how you want it.

[Madeye]

That looks amazing.
Amazing what you can do with a bit of knowledge.
I would have just sold the boat and bought one with a casting platform

[Thunderace]

The mighty dollar is a big driver, just can't afford a new boat
so far, aluminium $70, TIG welding 1 case of beer, Ply $50, hinges, stainless bolts and carpet $90, Glue $20, so about $230 so far

[snag]

Dont know if someone mentioned this but if you can put your livewell in the middle to make the boat more stable.
Most of the big boat companies do it this way...IMOA the better way.
My stacer has battery in the right corner and storage in the left corner with livewell in the middle.