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[The long Build]

Skimmer 400 Series RDSMB 003..

Well finally got mine onto the lake today with a few good test runs with various setups..  The first set up using a 6 cell NI-MH 3700 mAh 7.2v (I think a C size battery) may have been a bit heavy as I think I May have the first Skimmer Submarine !! I found that if you did not blast the throttle full ahead it went down.. But once going it was not to bad..  But Could be quicker.. The boat weighed in at 753 grams with the battery.

2nd run from a borrowed battery 7Ceil 8.4 2600 mAH made the boat massively lighter and it showed, no more diving  but the turns if a bit to sudden are quite violent , however on some calm water it really looked the part on the turn, preforming a nice drift..

Reverse was interesting   

So boat is now in the hanger now having the engine mount moved towards the bow , the rudder made longer and more into the boat, (having to build new ones as when I turned and the prop hit the water it must haveflexed it a bit and this took a nice slice out of the rudder and engine mount..

Sorry no pictures as tech crew forgot to put card in camera... .. Although some of the runs may have been caught on video.

Larry R.

[LarryW]

HI THERE LARRY,  nice to see you have skimmer on the water and under  ,
   my first scimmer took on water, but mk 2 made of styrene did not , .
 i run mine on a 3.700 mah batt fixed on velcro to adjust cg    ..... motor as standerd so is mount ,
  i think it all comes down geting the proping right ,   other wise no more vices ,  LARRY.....

[grasshopper]

Would the angle of thrust from the prop make a difference?

With the motor being mounted quite high, above the C of G, wouldn't the thrust have a rotational element that would force the bow down. Angling the thrust upwards would reduce that and possibly help lift the bow.. would combining thrust angle adjustment and moving the C of G get the craft better trimmed?

[Big Ada]

Ah Glasshopper!,

No, No and No,just bung it on and let rip, after all the swamp boats were knocked up by any one who could use a few basic tools, no tecky stuff for them.

Regards,

Len.

[gamma]

and this is mine 













I am not a beginner but i enjoied to build and ride this model, the driver is scratch built with balsa wood 

[triumphjon]

having looked at your models for a while ive been debating weather they are within thte scope of being made by younger inexperienced members of our comunity ? persumably they will also operate on grass as well as water / ice ? ?  jon

[Roadrunner]

Building these are as easy as building a springer, so i guess the answer to your question is yes....

Only tricky bit would be the motor mount and the prop cage but then even an inexperienced adult could help knock those bits up.

Anyone want to hazard a try at knocking up a free basic plan? I would but i have too much on to even consider messing around with CAD.

[GG]

To Roadrunner and anyone else thinking of "knocking up a free basic plan".
I'd rather you didn't as this plan has published twice, RCME Feb 1997 and Model Boats Sept 2007 thus establishing copywrite.  The prototype is still in my possession too.
Glynn Guest

[Roadrunner]

Wouldn't that only be copyright for your plan, not to be a stickler for these things but any plan i or someone else draws up, that would be of mine or their own design that wouldn't be a breach of your copyright...

Anyone want to hazard a try at knocking up a free basic plan? I would but i have too much on to even consider messing around with CAD.

besides ^^ i have to much on, to knock up a plan of something pretty simple to build without a plan 

[grasshopper]

Glynn,
A few questions if you don't mind.....-

I'd rather you didn't as this plan has published twice,

Does that mean 'do it and get legal action levelled against you' or ' do me a favour and don't do it' ?

As full size airboats were around long before you produced your plan, if someone was to produce a 'free plan' of an 'air boat' of their own design would they be infringing your copyright?
Would this be the situation if someone was to do their own study, design an air boat and then produce a plan without having seen yours?
If someone was modify your plan / design and make it vastly bigger / better or more scale like and then produce a plan from that would it still be an infringement?

In the case of a 'free plan' acquired from a magazine for no extra cost. If it is duplicated and passed on for no further cost is this an infringement of copyright too?

[Roadrunner]

Think hes worries that a free plan would loose him cash.

If you took his plan and 'modded' it or made it larger then it would indeed be a copyright infringement, but as i said...

Knocking up a basic plan thats freely distributed that myself or someone else has designed wouldn't be an infringement as its your own design, and not a copy.

Like a said anyone can knock up a flat bottomed boat with a sloped front and a flat deck, some round bar for the cage and a block for mounting the motor on...
Air boats have been around for years so the design of GG is really a copy anyway. It's pedantic s when it comes to copyright.

I may even knock up a plan later this week just to prove how easy it is to make a plan of something so basic.

[The long Build]

Guys.. Can we keep this  on Topic Please, Ie Nothing to-do with Copyright  or Not..

Yes the Plan we have built ours from is GG’s However to the best of my knowledge is Not Available to purchase as a Plan and can only be purchased through Ebay or such Magazine companys as I would not Imagine MHS have this issue still..
Also on “Dual Survival was a very good shot of an Air boat , One which could easily be knocked up into a plan with No Copyright infringement , But Why Bother when GG's is easily available and there our plenty of places you can download free designs..

Also the original GG plan was further developed in MB November 2008 by Brian Johnson into 3 different variants..

So lets just build Skimmers..

[GG]

Grasshopper,
           I'd rather it was not done because it leaves a nasty taste.  The original Skimmer design was copied by someone and published in a Dutch magazine, even down to the exact metric sizes that matched the Imperial sized original.  Too blatant to ignore and I understand that the magazine were none too happy with the "designer" of that plan.

Yes, airboats have been around for some time, as have models of them.  I have never claimed to have invented airboat models, but the plan that started this thread off is mine (see first post).  I believe that the simple small balsa hulled airboat powered by SPEED 400 type motor was an original creation, but would always welcome any information to the contrary.
There is no such thing as a "free plan" in a magazine.  The publishers pay the designer for the right to publish the plan which might then become part of a range of commercially available (from the publisher) plans.  People who buy the magazine pay for the plan and are free to build models based upon it.  They do not buy the right to offer copies for profit or not.  Fair use is allowed but putting someone else's plan on the internet would seem unfair.  I suppose that it is a bit like buying a book by a popular author, covering their name with liquid paper and writing your name over it.  I cannot see anyone wanting to publish it nor would the knowlegable public be fooled.

To quote Robert M. Pirsig "The solutions all are simple - after you have arrived at them.  But they're simple only when you know already what they are".  So, yes I try to design "simple" models but this can only be achieved by wading through a lot of problems, mistakes and even disasters before the "simple"and "obvious" solutions are found.
Glynn Guest

[grasshopper]

Not that I've ever built anything worth making into a plan, but I have been known to make something similar to a plan. Thanks for the reply Glynn, I am now that little bit wiser...

[LarryW]

hi GG put a feather in your cap , that There's a bunch of modelers out there who wants to build this great fun model ,
 its not hard copy or build so keep on producing your great easy builds ........LARRY W.....

[The long Build]

Well just rebuilding the rudder and repositioning the engine, also Remember the old saying "Measure twice cut once" (or something like that) well I did'nt and it turns out I am 1/2 inch short on the width, or to put it another way 1/4 inch each side.. Not sure how that Happened    so going to add to the sides with some dense foam or similar to add a bit more floatation.. Also just waiting for a battery to be delivered to add a bit of Va Va Voom.

[LarryW]

HI LARRY  , nice to see you are back on tracks , after all that winging , what power pack is it?.......LARRY W .

[The long Build]

Yes still here but tools are all over the house and keep going missing    so I have the solder but the iron has walked..

Its a 7 cell  8.4 1600 mah  but only weighs 150grams..

Did you see the Dual Survival Program ?.. The Skimmer they showed had a full set of about 12 spotlights on the front..

I have another top secret build in the Pipeline, but thats for another day..

[LarryW]

HI LARRY, i have the same problems with tools , but its mostly decorating kit , yes her in doors wants to ....
  change the decor to match new curtains, i wonder i put those brushes,
    where did buy batteries ?  and whats secret build ?
   just finished a couple footys and now started a working narrow boat .......LARRY  W ....

[The long Build]

Unfortunately no pictures but
another test run today with the new battery installed, Engine moved back and a new rudder, with apparent  success, the lake was pretty calm , had to be a bit careful as loads of ducklings were out and about and quite hard to see, although like there parents they seemed little bothered by the boats, on a few good runs it sped off like ice-cream off a stick 

Was quite surprised how long the battery lasted as well, only problem was that the force moved the motor back which meant that the prop is now about 2mm shorter at both ends as it then started to hit the cage, (I built the hull 12mm short in error !!)
Also the prop then started to slice into the litho plate holding the motor on which has cut a few mm in on each blade .

So repairs required after test run.
New Prop..
Motor repositioning .
Cage repair, was suggested that I wrap some fuse wire around the joints and then solder, so will give that ago..

But regardless of the repairs it was pretty fun.. Thinking of building a ski jump for it as well..

###
Bobby also had a run with a new 7.2 3700 Battery and 480 motor.. It flew around the pond..

[The long Build]

and this is mine 







I am not a beginner but i enjoied to build and ride this model, the driver is scratch built with balsa wood 

Gamma
That is a very nice and  tidy build..
Your lake looks great as well

[triumphjon]

ive started to build a couple airboats as well , ive slightly modified the hull by having slightly angled sides and a very small chine before the bottom skin , my intention is to use one boat as a rescue craft to push my yachts out of the seaweed ! will post photos when ive started to make the hull etc . jon

[nige2307]

But regardless of the repairs it was pretty fun.. Thinking of building a ski jump for it as well..

  Would be interesting to see !
Get c/g wrong or angle of prop and it could be a stunt air boat !
 Freestyle....everything else is doing it, bikes, cars, snowmobiles, etc, etc,
New extreme sport  ?

Could freestyle tug boating be possible...i wonder...!

[triumphjon]

what angle should the prop sit at please , & where is the best position for the battery pack to sit ? at the moment ive got an opening about in the centre of the hull facing aft to the transom . hull is 400 mm long x 200 mm  beam x 50 mm from the deck to the hull bottom ! jon

[The long Build]

i have my prop verticle to the hull, but did wonder about tilting it up a few degrees.  battery wise really is dependent on the weight of the cage , motor etc but mine is about 1 inch back from the front of the opening but it is a smallish battery 175grams