Bimini design for G21

[josemolino]

Hello,
When I bought my boat, I decided that either $3500 or $4500 was too much money for a Bimini no matter the design, the material, the fabric...
Now I need one so I have decided to build it myself.

My objective is to avoid machining, bending, welding or any operation that requires special equipment. So I came up with the idea of using ready to assemble parts from other industries.
I am using only stainless steel or aluminum parts such as:
Tubing 30mmx 1,5 and 25mmx1,5
Connectors and angles from food and chemistry industry (piping). Picture 2
Clamps from the cinema industry: the ones used in lightning to clamp tubing structures. Picture 4
Clamps from other industries used to set up structures. Picture 1
Marine parts. picture 2
Cable(plastic covered)

[josemolino]

Here you can see the beginning of the structure. In the third picture above you can see how the connectors relate to tubing.
The two tubes in the first picture ("pillars") are 30x1,5mm and the rest ("frame") are 25x1,5mm. I cut the pillars right away in metal, but for the frame I used PVC to do a first trial before cutting steel.

One issue is that the tower horizontal plates are not parallel so I had to slightly modify the angles by inserting washers below the aluminum clamps (in the second and third picture you can see a slight inclination of the right pillar)

[josemolino]

To set up the fabric I started by assembling the frame in metal. Then I put paper tape along the "frame" to protect the metal and then double side tape on the top of it.
That allowed me to stick an old fabric (I took an old bed sheet) along the frame so I can use it later as a model for the definitive one in marine fabric.
In this first pictures you can see a balanced structure


In the following pictures you can see the "sheet bimini". My wife says she loves the flowery look.. haha.. It is wrapped and sticked around the frame but it is tense enough. In fact it was really windy that day and it held perfectly...


And now I am at home sewing the proper fabric. More pictures in a week or so.... IT WILL BE GREY

[Paxdad]

Good job! I like it.....

[josemolino]

I have finished it with proper canvas. It is not fully tensed as I have to wait a couple of weeks until canvas settles

[JoeA]

Looks great! How much have you spent in materials and how many hours have you spent researching, picking up material and assembling?

[josemolino]

I have spent 500$. In terms of time, research was the longest part. I ordered everything by internet but the tubing and some minor bolts & materials. However, I took it as my winter project and I have enjoyed every moment. I mostly did it during weekends and I could never work more than 2 hours in a row
I´ll be generous with hours so you take the worst case:
Design: (2-3 weeks)
8 hours internet, 1 hour telephone, 4 hours design & redesign
Construction (2 weekends):
1 hour for cutting & finishing tubing. 7 pieces
1 hour for making assembly holes with screws in the tubing. 10 in total
2 hours for measuring and re-measuring and re-re- measuring before assembling the clamps picture 1 to the tower plates ( as I had to drill the tower plates). The most difficult part was to make both pillars parallel to the ground by inserting washers.
1 hour to place, tense and make marks with the trial tissue.
1 hour to translate design and cut the final canvas
2 hours to saw the whole canvas border with a protection strip.
4 additional hours for assemblies, trials in order to modify sewing to get the final tension.

What is missing now: leave the bimini in place for some weeks and slightly modify sewing to eliminate the remaining wrinkles. (let´s say 2 hours)

[JoeA]

Well done.