Reported Post by Naptalene

Naptalene has reported a post.


Hello, I cant put an edit on this post of Mine.
I just wanted to put
“THIS WAS A DISASTER - DON’T USE THESE LINES. I’ll post up correct ones when I get it correct”
So people don’t waste their time on these.

Could you please put that in for me?

Post: n-Arrow3b build
Forum: General Discussion (RG65)
Assigned Moderators: N/A

Posted by: Naptalene
Original Content:

The bulb…

I kept whacking numbers into the bulb calculator and came up with this shape.
It gave the lowest wetted surface which is what I thought I was aiming for.
But I have since read some threads (RCGroups IOM or Marblehead IIRC) where guys mentioned that although you want it to have a low wetted area, you also want a streamlined shape as opposed to a wider, blunt shape.

So I’m just running with this for now. I was hoping to build 2 boats, so If the mood moves me I’ll try build a different shaped bulb for that one and have a drag race (Get it… drag race…drag… I know, it was bad)

Bulb PDF for printout and the settings I whacked into the calculator.

If you use this PDF double check the scale when printing it out. For some reason it kept printing out too big so I had to adjust the scale.

The balsa bits…
I cut them from 2mm balsa which should be too thick, but i figured that it will be easier to grind off extra weight rather than add it.

By preference I would like to do what I’ve seen in Claudio’s build and cut lead sheets and glue the bits together, but I can’t get lead sheet easily, so I would have to pour my own - which defeats the point of trying to avoid molten lead.

So what I might try is this:
I used a rasp to remove lead from a sinker on the Apsara I built. These lead shavings work out WAY cheaper than any leadshot I can find (sinker is R70 so that works out to $4.50 for 600g). So once I shape and build a plaster mold I’ll try use those shavings and epoxy to build a bulb. I’ll just need to be aware of spreading the shavings equally in the mould.

If that fails, I’ll have the 2 part mold to pour the molten lead anyway. I have done it once so I reckon I can avoid killing myself.

Any input on any of this will be greatly appreciated.