New Nylet Spirit is here! Progress at last!

[Andy Ashwood]

Hi David,

Nice build log, thanks for sharing.

I was particularly interested in the LiPO's you are using. I need to shave about 100g of the weight of my gadget and changing to LiPO's seems like one way of doing it. Being a bit of a nooby when it comes to electrics I was wondering though why the battery pack has two leads coming out instead of the normal one. Is it just to get a different connector or is there some magic at work here? Also, do you need to have a special charger for LiPO's? Finally, where did you source yours from?

Cheers,
Andy

[Hiljoball]

I use lipos and they are great but there are some issues with using them.

In the boat you would use a 2s (2 cell) but that gives about 8.6v fully charged, which is too much for normal receiver and servos. So you need a voltage regulator to drop the voltage to (say) 6v. If you use an RMG winch then you are all set. The RMG loves the voltage and high current flow of the lipos and it supplies 5v to the Rx and rudder servo. If you do not use an RMG ten you need a voltage reducer. See below.

The extra plug on a lipo is for 'balance charging' (charging each cell independently to its max). This is not needed on every charge, but periodically. If one cell gets out of sync with the others, on a normal charge, it may overcharge and explode.

Yes. you need a special lipo charger. see below.

This is what I use.

This is the Tx battery I use. It fits easily in the my Futaba 6EX case. The 3s lipo in my Tx is good for two days of racing. I bought two.

http://www.hobbyking.com/hobbyking/stor ... oduct=9787

The 2s lipo in the boat last almost all day. I bought three. I looked for a format that is short and fat to fit in the pot, (not long and skinny).

http://www.hobbyking.com/hobbyking/stor ... oduct=9165

To charge the Lipo (but it does other types too) I bought and am very pleased with

http://www.hobbyking.com/hobbyking/stor ... oduct=9165

It needs a separate power supply

http://www.hobbyking.com/hobbyking/stor ... duct=11758

In my non-rmg equipped boat, use a voltage regulator to reduce the Lipo 2s voltage to 5 or 6v is

http://www.hobbyking.com/hobbyking/stor ... oduct=6313

To keep the lipo batteries safe while charging, I use one of these.

http://www.hobbyking.com/hobbyking/stor ... oduct=4364

John

[Dave Pickett]

At last!!!

OK finally got on with it. Mixed up the epoxy with some micro balloons and cut loads of packing tape ready. spread the glue, deck on and tape it all down - couple of pictures.....





hopefully I will progress the rest of the build a bit quicker!!!

[Dave Alston]

I have been watching this build for what seems an eternity, October 2010, but I guess you are not in a hurry.

But as an observation – your electrics will rot away particularly if you sail in brack or salt water – beleeeeve me. Sand on your head water will get into the hull particularly through those sexy fairleads for the sheets

You will undoubtedly close the deck with patches and because this is inconvenient you will leave them in place after sailing. The hull will sweat and every connector will rot in quick time. The Eurgle winch gets very hot and when it cools down it sucks in saturated air and it too will rot.

If I were you I might think about it again. Particularly galvanic corrosion while you are sailing

I do hope you sealed all that wood with sanding sealer or varnish, it too will rot very quickly- dont stop now lets see it sail- we have two at our club and they go ok. I measured both of them and they were dead on target-

Oh = weight - you can save more weight in the mast than anywhere else.

Just an observation

[Dave Pickett]

Thanks Dave, Good advice which I hope others following this thread (if there are any!) will follow.

I spend a lot of time on my modelling, and as you say I am in no great hurry. This really is a project for me to enjoy in my retirement years which are still at least a couple of years away. I am currently racing mardave 1/12th oval cars which takes a lot of my time, especially preparing the cars.

I am unlikely to leave stuff in the boat from week to week, as I always prepare thoroughly before a meeting, and originally started model boats some 40 years ago so I know all about water and electrics. Before I joined the hull I did check that I could retro fit the radio tub and this would be possible - we shall see whether it is an issue.

I wish more people would comment, it would help others building an IOM there isnt anywhere near enough info on the web IMHO.

[Dave Pickett]

PS How can I save weight on the mast???

[Dave Alston]

A few tips

• Use a lighter section- there is a 0.5mm wall mast available. Needs very careful hound and spreader positioning but will save 40g just to start with.
• Backstay crane should only be long enough to clear, 2mm, the back stay from the roach of the sail- cut off any excess. This will reduce the bending moment on the mast - and save a gram or two of weight.
• Limit the numbers of screws and embellishments
• Use an arrow shaft as a boom- the Bantock system is very good but it weights a ton with the fittings.
• Use the plastic goose neck and booms from New Zealand in preference to the Bantock. It’s a lot lighter and is easier to use- no special tool required.
• Use a 37g/m Main and Foresail in preference to the standard 50g/m if you are careful about handling.


Before you know it you have saved 150g but most importantly in the correct place. There is no point in saving 100g in the hull and then adding it back to the hull as correctors

Your hull is Ok on weight, Frank at Nylett saw to this in the design and manufacture. All the sexy wood is what kills you in the hull.

Do not fill the bulb with putty, paint, resin etc. Its density is less than water so you are actually lightening it with respect to the water and making it heavier in air. – Now that will take some thinking

If you need to smooth it off –
• Rub it with a hard metal object like a screwdriver or lightly tap it with a flat bar.
• Minimum paint –if you really must paint it.


Fin / Rudder Alignment
You cannot do it by eye. Simply fit the fin and rudder to the hull - lay the boat on its side on the edge of a flat surface – fin- without bulb and rudder. Look at the rudder in relation to the surface. Flip the boat over and compare

[Bruce Andersen]

Actually, aligning the foils is pretty easy if you have a laser level (the kind that builders use to project lines on walls etc). Put the boat deck down in the building stand and level the chainplates, then use the vertical laser line to align both foils at perfect right angles to the chainplates (and thus, square to the rig).

[Dave Pickett]

Some great advice coming out here, its helping me and I hope its helping others!

Disaster, the epoxy did not grab the glass fibre at all!!! (I have never really liked epoxy for this sort of join) so deck is off again and plan b is to use glass fibre resin and a strip of glass tape around the joint, that should get it!!!!!

[Dave Pickett]

Dave Alston,

I am sure there are others that share your frustration at the slow progress of my build, but I make no apology, I am doing this as and when I feel like it!

Would you be kind enough to post some pictures and details of the Spirits in use at your club, I am sure many folk reading this thread would appreciate it.........and it will add to the info available on the web about IOMs in general which I do feel is lacking.

[Dave Alston]

No No stop - you are about to make an almighty mess.

So it did not hold. Regrettably it never will and it was very luck you spotted it.

You added micro-balloons, it makes the epoxy brittle and cracks when the boat flexes and flex it will. You probably also did not play too much attention to the epoxy mix ratio.

The bottom line is that nothing will bond to epoxy it will only adhere to it. You need to make the deck mating area as rough as you can and I mean rough, 120 grit rough. The epoxy adheres to the cavities the abrasion creates and the glass cut when the grit cuts it. Do not touch the abraded area, just blow of the dust with a clean brush.


That lovely wooden strip along the hull; you need to taper the hull and wood until you get a fit. Use a Permagrit flat file up and down the edge, it should take you about an hour.

But the step before this is step, the fitting, polish the hull and deck with some good polish at least three times over three days, you should have done this on day one- it stops the glue getting all over the pretty gelcoat.

You do this step before you rough it up on the joint so the any polish that gets on the joint area is taken away when you abrade the joint area. Do not use any solvents.

The glue- 30 minute or longer Z epoxy or Devcon. Mixing the epoxy is critical, get out there and purchase a Jeweller’s Scale 0- 200g 0.1 g divisions should cost about $8. Next go to McDonalds and get a burger and put 20 of those nifty paper sauce tubs in your pocket - don’t put any sauce in them. Take them home and weight out equal mass of epoxy and hardener into a tub. Two batches of 20g of each in two tubs should do it not one batch of 40g in one tub - the exotherm will be too fast. Mix it very well, at least 2 min. being sure that the room temperature is around 21C – to cold and it will not link properly, too hot and it will go off too quickly. Put a good bead of it on the wood strip. While you are doing this get someone else to wipe some epoxy onto the deck joint area with their finger - just enough to wet the surface. If you are alone do the deck first.

Plonk the two together, invert it so the deck is on the bottom. The excess glue will not run down the hull then. Leave it for at least 24 hours. Do not wipe it of fiddle about with it, the glue will not adhere to the gelcoat because you polished it.

So now you know how it’s done. I don’t do it quite like that because I have the mould for the deck and hull so I have jig to clamp the two together in the correct place. I also place pealply in the layup on the deck as the last layer and around the seam are of the hull. This provides a good key for the joint and I use Epidermix 372 which is probably not available in your country. It has good wetting properties and is slower.

Aligning the rudder and fin by laser – I really don’t think so - Just put it on a flat surface. I have two 3/4” ply boards 1 metre long fixed at right angles to each other and two blocks 150mm thick and 300 mm long.


Place the top of hull against the vertical board, Block 1 under the fin and lump of lead on the fin. Pack the end with a sliver of wood half the taper of the fin thick. Block 2 goes under the rudder. One step- Fin is square to the hull and the rudder is in line with the fin and the stock is in the vertical. This is the most accurate and quickest way believe me.

Ok so now you are back on the road- stay there- next week we need the saiing report - summers all but gone now.

[Dave Alston]

Just looking over your pictures again – I think the fin box to hull joint is none too good. It will surely fail with the slightest bump. There is no sign of abrasion and no sign of roving in the fillet.

!!!! Your last chance to think about what you have done !!!

Now put that $£$” Laser and Micromagic away and lets focus upon the job in hand, after all this is a IOM forum

Your earlier posting ... Believe me this is a slam dunk - the radio and plugs will rot away in leass than 6 mouths. - You will leave a patches on an it will rot even if you take them off. There are very good reasons why most do not do what you are doing - but I guess you know best -

Go the Two Islands MYC and you can see the Spirit results - Oh and I really do not care if you ever finish the boat but I do care about you doing it properly.

[Bruce Andersen]

Don't be afraid of modern technology - the laser will accomplish in seconds what scraps of wood of various sizes may do in minutes to hours.

I take a large level and place it on my building bench then shim it to be perfectly flat.

Put the hull (deck side down) with its chainplates resting on the upper surface of the level - now the boat's rig attachment points are perfectly horizontal.

Put the keel (without the bulb attached) in the trunk and tighten the attachment nut enough to hold the keel in place (protruding straight up) but still able to move about a bit. Place the laser level on the workbench & turn on the vertical beam (this will be perfectly vertical if it's a self-leveling laser) and align the fin to the beam.

Shim and build the fillet to keep the keel in that position.

Duplicate for rudder.

Take the wooden planks and use them for firewood (or hit yourself in the head with them once you see how easy this is)

[Dave Alston]

I don’t hold much with them fancy new fangled gismos. It were ard enough tipping away the pitch and animal glue. Gime a yard of string and a bob an ill be telling yu exactly which way down be an the numbers 3,4,5 ta tell which way be square. Fur horizontal you need only a length of tube and measure o dark rum. An when ure done u can drink the rum an regale the wife wif tales of o ardship at the pond over ure vitals.

[Barry Chisam]

Looking at the photos you have posted the hull appears to be moulded using chopped strand matt.
If this is the case then the resin used in moulding is probably polyester.
Once again if this is the case then epoxy will produce a poor bond.
You realy need to contact the moulder and get their recomended bonding material.
By the way nowadays most IOMs are moulded using epoxy resins for strength, weight saving and longevity.

[Dave Alston]

Well spotted Barry,

I never spoted the clue and I would not have believed that it would have been laid up in an estery.

Now Mr Picket - Take heed - Yu eard it from the man what do this fur a crust fur many a long years an does a fin job, peraps a ltle too slowly fur some, but none the less a fine job and be most noted fur his work in controling fish stocks in Falmount.

[Dave Pickett]

OK well given the tone of a couple of posts on here I seriously considered removing the thread completely.

I am not going to get back to this for a short while as to be honest at this moment I'm not completely sure I want to be part of the IOM scene.....

That said, there is some useful info on here that others can perhaps benefit from, so I'll carry on in due course. Even making a hash of joining the hull and deck has brought out some useful info that all can benefit from.

For those interested, recovery from the hull and deck disaster appears fairly straightforward. A heat gun turns the epoxy quite soft and it then just peels off. A test patch using glass fibre resin and tape produced a very strong joint, the process is

- paint some resin onto the area around the hull
- place a strip of gf tape on top
- paint more resin on top and onto the mating surface of the deck
- join and using packing tape to tape together

As I said before, I have never really trusted epoxy in this type of application, now I realise I should have used glass fibre from the outset.

I now need to work out the ratio of hardner to put into the gf resin to allow sufficient time to get round the whole hull.

One thing you may like to ponder on:

My experience covers 40 years of model making from bread and butter based scale boats to glass fibre and everything in between. I have built and flown RC aircraft and raced RC cars at a high level. I have also rebuilt two classic Minis stripping them right down, teaching myself to weld in the process. Engines and gearboxes stripped rebuilt etc. and even sprayed the final result achieving a professional finish. I also built 2 full sized kit cars (a Marlin and a Robin hood)

So what?

If I am finding building an IOM challenging, how the hell will the vast majority of people cope?

One final and important point - in no way are the problems I have had related to the quality of the Nylet kit - it is down to my inexperience in building.

[Bruce Andersen]

Dave

Don't despair - all of us have had build failures (perhaps not quite so public however!).
Also, don't let the tone of some of the posters turn you off to IOM's - as with most web boards there are a vocal minority that tend to set the tone of class by proxy but rest assured that the remaining 99% of IOM owners are pretty decent folks that want the class to grow.

[Derrick Young]

Dave Would like to thank you for the build log. Seeing some of the challenges you have faced and how you have managed them no doubt will help me over the winter with my IOM project.

[Dave Pickett]

Well guys I am still kicking around!

Thanks Bruce and Derrick for the encouragement, I do feel there is so little on the web about IOM builds that hopefully this thread will prove of use and my mistakes can be avoided by others!!!

Next job is to use the GF resin and fine gf mat to join the hull and deck, my initial trial proved successful, might even be this weekend, Sunday should be free after I have finished painting the kitchen on saturday!

Apologies to those who have been looking for progress, it will come but I am at crossroads here and what to move forwards the right way! I am mindful of the value of the radio pot, and there is space to retro fit if required, but at this stage I am going to go with my initial radio set up and see how it goes.

Oh here's another distraction that has just arrived:



I am much more comfortable with nut and bolt joints than this new fangled glue stuff!!!

[Dave Pickett]

To quote from the Kingston Mouldings site:

It’s quite simple to bond wood securely to GRP. The first step is to lightly sand all areas where adhesive will be applied, brush and/or vacuum to remove dust and loose fibres, and finally wipe clean with a little acetone or cellulose thinners on a rag, before applying adhesive. The most suitable adhesives are polyester (fibreglass) resin, or alternatively a 'slow' epoxy adhesive such as Devcon 2-Ton. Most of the 'fast' or '5-minute' epoxies are not quite as good for bonding to GRP. If using polyester resin, I often find it helpful to thicken it first by stirring in a small amount of P-38 or Plastic Padding filler paste. The extra viscosity stops the resin running downhill from wherever you apply it, and the improved gap-filling properties mean that your joints don’t have to be made quite so accurately. Whatever adhesive you choose, use large numbers of spring type clothes pegs to clamp everything until the glue has set.

Any comments? Would anyone mix micro baloons in the resin to thicken it?

Looks like I am on the right track with the GF tape and fibreglass resin.....

[Don Case]

Hi Dave
This is not going to help much but I read somewhere that you shouldn't use microballoons to thicken glue joints. Don't know anymore than that. I use something called "Cabosil".
http://www.cabot-corp.com/Silicas-And-A ... 0522PM972/

Don

[Dave Pickett]

Thanks Don I suspected as much. Its getting cold over here which will keep the resin a bit thicker and slow the cure.

All of the epoxy glue is off the hull and woodwork, easy to do with a heat gun and sharp chisel! At least I am back to square one without any damage.

With regard to the keel box I followed my instincts and used GF resin and tape - it's solid.

[Dave Pickett]

OK well I have just re glued the hull and deck, no pictures as it looks just like it did before. Will it work this time? I am not going to touch it for a few days, maybe not until next week end. So what have I done differently?

- Used Devcon 2 ton rather than 30 minute epoxy
- NOT added microballons
- Sanded the GF deck to roughen it then used thinners to clean off

I have done a number of small joints using devcon on the GF and it seems fine. I am fairly convinced the micro ballons and 30 minute epoxy were the issue, we will all know next week end!

I am hoping it works as it should this time after this there is only the keel/bulb and rigging to complete which really should not take that long.

I have also decided to use the radio pot and have fitted this into the deck, it is quite close to the running rigging but I am sure it will be fine.

At some point when I retire I am considering buying just the hull/deck and mast boz to build another using what I have learned from this build.........................................

[Bruce Andersen]

I can attest to the utility of building up your second hull (don't ask for the details please) - faster, lighter, easier, and straighter than the first by miles! Put the first one on the mantle and race #2.

[Dave Pickett]

OK tape is off and the bond is good. Have started trimming the overlap and it's looking good. Am considering putting a thin strip of varnished wood (1mm x 4mm or there abouts) over the join, this will tidy it and make the joint totally watertight - not necesary but will look nice and will add to my confidence in the join.

Have started work on the rig, photos this weekend................I actually lost all interest in this when the joint failed, my enthusiasm is now returning!

[Dave Pickett]

So, tape is off and the joint appears to be very sound. Deck trimmed back ready to put a strip of 1mm x 5mm along the top to neaten the joint further.

Hull and deck complete:



Close up of part of the join:



Top view showing the radio pot



Slightly concerned that the main sheet will rub against the side of the pot, will try it and if it is a problem I'll move the pot over.

Ok next up are the strips to neaten the joint, then on with the Rig......

[Dave Pickett]

Well the next task is to fit the shrouds so I can progress with the rigging. I had already strengthened the area where the shrouds fit, and it's simple enough to drill the holes, but fitting the nuts was always going to be a challenge!

In the event it was really simple, I made a "spanner" out of soft ali, held the nut on with a piece of double sided tape, and inserting the spanner through the servo access holes (and using a torch!) I was able to get the nuts on pretty easily.

I now need to work on getting the mast as close to the deck as possible.

photo below shows the ali spanner and the mast/downhaul and spars....

[Bruce Andersen]

some vinyl tape along the gunwales will "clean up" the look of the deck/hull joint, make it more waterproof, help minimize collision damage, and be lighter and easier than strips of wood.

[Dave Pickett]

True Bruce, but the wood forces a bit more glue on the join, 1mm mahagony weighs nothing and looks good in a retro type way!

Will post pics once I have varnished them!!!!!

To be fair the joints looked pretty decent anyway......could have just left it.