New Build

[Andy CParticipant @andyc56856]

So, izzy had a turn with Tom's fire boat. Bad idea. Seems the Goblin/hibiscus is now not fast enough. although tom's boat is an Ashley LCM converted to squirt water, it actually moves goes quite fast. It probably is not designed to plane, but it almost does. It only has a Speed 400 in it but she has a good turn of speed.

So, now I have to build a speed boat. Izzy had a look through all the plans and originally thought she liked the look of a Huntsman or Swordsman. I don't have a swordsman plan, although I do have a huntsman. Cool, I though, nice choice.

Until that is she saw the Vivace from Glynn. Guess which one I am now going to try and build.

NQD jet drive of all things. Fleabay to the rescue or at least it will in 2-3 weeks when it gets delivered.

So out with the plan and build log from the magazine and now reading through it to see how it all goes together.

Will keep you posted.

andy

[Andy CParticipant @andyc56856]

Glynn Guest Vivace

[Andy CParticipant @andyc56856]

Okay, so plan transferred to tracing and layout paper. All cut out ready to apply to the wood.

Using balsa as per Glynn’s original design.

[Andy CParticipant @andyc56856]

Hi all

Made a little bit of progress on the Vivace. No pics just yet, but will put some up later. I have a question though. The plan calls for the hull skins to be 3mm balsa but can I use ply instead for extra strength? According to Glynn the boat is very susceptible to being top heavy so will the use of ply bring the centre of gravity down and so make it less top heavy. Or will it as I suspect be to heavy an not suitable for the hull.

Andy

[Dave MilbournParticipant @davemilbourn48782]

Andy

A personal view here – please forgive me if it looks like I'm having a pop at you because I'm not. I am trying to broaden this out to make a more general point:

The hull was designed to be made from balsa, not plywood. It is never advisable to change one of Mr Guest's designs without a very good reason and, as you probably suspect, you haven't come up with one. He does read this forum, you know! Please don't take this as a criticism of you but IMHO too many people take a look at a perfectly sound design and decide that it isn't strong enough – like they somehow know better than the guy who not only designed the thing but has also built and sailed at least one more than they have. The question to ask is "strong enough for what"? If your total list comprises of head-on collisions with the bank or other models then just add strength to reinforce the bit that might be damaged that way i.e. add a hardwood stem strip. On a balsa hull I would do that anyway as a matter of course.

Take my word as someone who has designed one or two models and follow the instructions. They were written for a purpose. If you find on sailing the model that the entire hull somehow isn't strong enough then consider adding some localised reinforcement inside e.g. glassfibre and resin. If the design is top-heavy then be sure not to exceed the material sizes for the superstructure. Add a little ballast if necessary – you can always remove it later whereas you can't remove weight from a hull which was over-engineered in the first place.

The days when all model boats were powered by thumping 2-stroke diesel or glowplug motors are over. Modern electric motors are totally smooth-running so thick materials for the hull to absorb the vibrations are no longer necessary and we can build lighter, faster and therefore cheaper. If the problem is that other models frequently collide with yours then either pay more attention to where your model is in relation to others or go and find somewhere else to sail. GG himself has written a short piece in the latest issue of MB headed "Sail like you drive". It's worth reading.

Soap box back under the bench. Good luck with Vivace!

Dave M

[Andy CParticipant @andyc56856]

Hi Dave

No offence is ever taken, especially from more experienced builders, when I ask for help or opinions. This is only my third ever boat build so I am still learning. I will stick to the build instructions as they are written. As you say I can always add a bit of ballast once it is finished.

Cheers

Andy

[Andy CParticipant @andyc56856]

So a little photo update. Jet drive installed. Did not see Glynn's little note about leaving out until later un the build but hey ho. It is in and looks good. A bit on the heavy side but will see how it goes.

Shot of it in the drive bay.

Started the side skins. From the stern forwards as per instructions.

 

More to follow.

Cheers

Andy

Edited By Andy C on 20/02/2018 18:41:33

[Paul TParticipant @pault84577]

Andy

To put the cat in with the pigeons I have to agree with your choice of building materials, before people start bashing their keyboards this is not to deride Glynns design choice nor to argue with Dave……I just don't like balsa and prefer the predictability of plywood.

I'm not sure that building out of ply instead of balsa will do much to lower your models center of gravity but ply will certainly add strength and reduce the amount of damage should an accident occur.

Looking forward to seeing your build in the water.

Paul

[Andy CParticipant @andyc56856]

Thanks Paul

Stuck with the balsa in the end. Just need to make sure I seal it well. Glynn's method of sealing seams quite sound and he does it that way all the time so not going change things now. I know there a lots of ways to do it, and as I have never done it before I think I will stick with what is printed.

Should be a fun model to whizz around the lake. some funky Colour choices going on but should be doable with Car paint.

Andy

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