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[Donald Salvato]

HELLO; I have a beautiful 33" mahogony RIVA AQUARAMA model. The foredeck planking has separated in a couple of sections due to shrinkage I suppose. It is barely noticeable , however the rest of the boat is pristine.Should I leave it as is to expand and contract or fill the separations. The bright work and varnish are otherwise exquisite. KIND REGARDS DON

[derekwarner]

Hi Don...& welcome to MBM 

The questions you ask would certainly be better understood with some good quality photographs, together wih some sizing width of the planks and  confirmation of the current deck plank finish

Urathane?
Conventional oil based varnish?
Two part epoxy gloss?

This information will allow members with a good knowledge of the subject to offer comment

Derek

[BrianB6]

Is it powered? If not it could be a Mauritian or Chinese model.   We were at a Mauritian model boat factory yesterday and they use French polish ( believe it or not) so repainting could be a problem.
They get a fantastic finish on their Riva's

[derekwarner]

Folks.......

Don has e-mailed some larger images & I have resized them

I certainly suggest he should not use the vessel on water until the repair is effected as even extremely high humidity could further degrade the bond of the planking to the foredeck

It's up to Don to come back with the source & hence the probable surface finish.....

If the vessel were French Polished [ala- Brian's comment], a localised repair could be effected.......infact a French Polish repair may be as easier to repair over Urathane, oil based varnish or two part epoxy gloss

A test for French Polish could be to lift the upholstered seat [or such] and find a finished surface that is not visible and gently wipe raw spirit  over a small area with a cotton bud. If it is a French Polished surface....an amount of redish dye will be transferred to the cotton bud

Would be interested to hear the thoughts of other members

Derek

PS...question for Brian.....Mauritius is on about the same Latitude as Australia, what was the humidity like yesterday? [lucky you ]..that would have been an interesting tour of the model boat facility ....maybe a good thread & read for our members

[derekwarner]

 ...the WEB timer beat me ...one more image................ Derek

[BrianB6]

S...question for Brian.....Mauritius is on about the same Latitude as Australia, what was the humidity like yesterday? [lucky you ]..that would have been an interesting tour of the model boat facility ....maybe a good thread & read for our members
About the same as it has been for the past 3 weeks.   26 - 33 degrees and humid.   Not the best time to come here but no option with Australian school holidays.
Historic Marine seem to be the best firm and their web site is
https://translate.google.com/translate?hl=en&sl=fr&u=http://www.historic-marine.com/&prev=search
there are a number of youtube films but it is difficult to photograph the models in their glass boxes. Search Historic Marine model boats on Google for photos
I will try and obtain some photos that others in our party took of the workshop.
They also make models to order but only static ones.

[SailorGreg]

Hi Don, that's a lovely looking model.  A few questions first.  Have you had the boat long? If you have just received it, it might be as well to sit tight for a while and see I anything further develops.  If you have had the boat for a while, does it live in a reasonably stable environment? (Where in Texas are you? It's a pretty big place - what sort of temperatures and humidity do you get?).  And is it a display model or a working model?


Lots of questions but a little more  information would help us give better advice.  Hope we can help you sort it out.


Greg

[SailorGreg]

Hi Don, thanks for answering the questions, although did you mean to do it privately, not on the forum?  Anyway, I'll respond here so others can add their views.


Since your boat has been sitting in a stable environment for several years, is for display only and you say that the split is difficult to see without close examination, my first reaction would be to leave it alone.  As soon as you start trying to do a fix you will almost certainly need to re-finish the foredeck.  Getting a good finish that matches the rest of the boat wil not be easy, even for an experienced modeller.


If you do decide to fix the cracks (or if, over time, you get more of them and feel you have to do something), I would suggest you do a lot of trials first.  Get hold of some wood similar to the decks (perhaps some mahogany strips from a model supplier) and make up a practice section with gaps between the planks (just glue the planks down to a scrap of ply).  Try filling the gap with a long splinter of wood and see if, when sanded down, that looks OK.  Get hold of some mahogany shade wood filler and try that in a gap as well to see if that works for you.  You may need a combination of wood splinters/shavings and filler to get a clean mend.  When you feel you have the gap filled properly you need to apply some finish.  Unless you know exactly what was used on the original I suggest you try a variety of finishes to see which matches the original best.  I suspect the original is probably a sprayed lacquer so you will need to try something similar.  Once you have achieved a mend on your dummy deck that gives you a good match to the original, you should feel confident enough to start on the real thing.


Good luck 

[derekwarner]

Well Don...if you would like a balanced response, you will only get it if you post the Q&A responses here for all to see

Just thinking outside the square, from the image you posted to me, it would appear  that the dark planks have not shrunk in width, nor the spacer light material...[card or light toned strips].....could you accurately measure the width of suspect planks with a digital caliper ...start at the windscreen and progress toward the bow....then also on 3  or 4 different close by planks & confirm

If this is the case the other possibility is that the entire width of the foredeck has moved or expanded [in width] as opposed to your original thought of shrinkage

So... a few more answers required.....

1. are the planks parallel and original width, or  are they measurably non uniformally thinner or shrunk in width
2. answer to wiping a non viewable section with spirit and a cotton bud ~~ transfer of dye colour
3. do you have access to the area under the foredeck?
4. some photograph's of the vessel interior construction
5. is the vessel display only?, or RC?

Derek   

[derekwarner]

Don...from the MBM page you are reading it is very easy to reply, which then makes it available for all members to read ...the detail is in the image below

I have your response however you only answer some points.....questions 2. & 4. would be very helpful

Awaiting your full reply here on MBM

Derek
____________________________________________

[Hi Derek; I must admit I'm new to this forum and am having difficulty how to post on the forum. Any direction would be greatly appreciated. To answer your questions as follows. The boat is a static display model. The planks are all the same width, with no shrinkage of any one plank. As you suggest it may appear a whole section has shifted. There is no way to get to the under foredeck. The separation is uniform the entire length from the wind screen to the breasthook. Again the separation is only noticeable upon very close inspection. I would hate to disrupt the overall quality of the model by any incorrect repair I might make. Thank You for your help. KIND REGARDS DON😎 ]

[Donald Salvato]

Derek; Finally with your help figured out how to reply. The answer as to wiping the finish on the RIVA with spirit and a cotton bud yielded no coloration of the finish reddish or otherwise. The finish seemed unaffected .Photos forwarded to you on the interior build.

[derekwarner]

OK Don......we now have a few more things to consider  ............so based upon

1. it is a static display model only
2. the planking strips being uniform and not thinned by shinkage
3. there is ZERO access under the fore deck
4. it is not a French Polished surface
5. you do not wish a complete strip down and replacement of the foredeck planking.....[and associated  ]

You haven't much choice 

On OZ we have a product called Mastertouch Carnuabra Wax.......probably a synthetic spreadable version of Bees Wax with a few modern day chemicals mixed in......[I am sure in the Land of the Free an equivalent product would be available]

Procedure 

1. place the hull in the sunlight for 30 minutes
2. take a small 1" square of 800 Wet & dry paper......fold in half.....insert fully into the depth of the crack & with gentle rubbing motion, loosen/remove those flaking thread sections on either sider of the crack
3. blow out the dust [won't be much] with a plastic drinking straw aimed into the crack
4. with a clean soft cotton rag, wipe the Mastertouch Wax into the crack....leaving a slight excess over the length of the crack
5. place the hull in the sun again for 30 minutes.....softly brush the clean cotton cloth along the length of the crack
6. any excess wax can be easily wiped off the adjoining planks as they will be unaffected by some simple wax

Outcome

The Mastertouch Wax will penetrate to the lower level where the planks join the foredeck timber. This will do what the label says...it will Nourish the timbers     which I suspect means adding natural oils back to the substrate of the timbers and hence preventing further drying out of the timber

If you found that the Wax literally disappeared after the 30 minutes in the sun I would not be concerned.......it's just gone to Nourish additional timbers in the foredcek

Be interesting to see what other members suggest

Derek

[Donald Salvato]

Derek; Thank you for the suggestion. I will try to locate said wax and try the procedure. I'll post later again thank you😎Don.

[SailorGreg]

Just for info, carnauba wax is derived from a variety of palm and is not related to beeswax (although the two are often mixed for many applications as carnauba is quite hard and beeswax softens it).  Carnauba is the wax most commonly found in car waxes as it produces a very high shine.


I reckon Derek's suggested method is a first rate way to fill those pesky little gaps. 


Greg

[Ron Rees]

Hi Donald,


It's such a shame that your Riva has a split in it, the trouble is, it will be quite tricky to fix properly or permanently.


I agree with everything Dereck has said and his suggestion about the wax. What I think has happened here is that these fabulous models are made in a country with relatively high moisture content in the air, they use local hardwoods that even though they may be properly kiln or air dried still retain the high moisture content of the area, They build the models so beautifully and whether they polish them or give them 50 coats of varnish or whatever the wood under that coating is still real living cells, though dormant when cut down. These cells expand and contract even many years after they have been used to make something and arriving in one of the worlds driest desert states (Texas) the wood will give up some of its moisture and typically try to shrink.


In your case the stresses of this have caused the wood...all of it...to shrink a little and a crack has appeared in the weakest point. You cannot stop this happening unless you keep it in a temperature/moisture controlled environment like they do in Museums.


It will also continue to expand and contract so sliding in bits of wood will cause this to transfer somewhere else.


The Wax is the only way to hide what has happened. In the UK and I'm sure elsewhere, from specialist French Polishing or craft dealers you can get a set of wax coloured sticks like Carnauba or Beeswax. These can be mixed by melting with a hot knife or used straight to get the right colour and pushed into the crack. Polishing with a soft cloth will smooth it and shine it and I wouldn't do any more.


Most of these are capable of conversion to R/C, I've got 2 of them. In fact the moisture may even help!!. The wax repair is waterproof anyway and will stop excess water getting on the substrate that supports the veneers.


Its a good thing it wasn't a Taiwanese Stradivarius violin!!! coz that would do the same thing....crack!.


Not a lot of good news here but I hope it points you in the right direction.
You could always move to Britain, we got lots of moisture here!!!


Cheers...........Ron Rees.

[Donald Salvato]

HI RON; Thank You for your comments. Where I live , very near the Gulf of Mexico, it is quite humid most year round. Your points are well taken though. I'm going to try the wax technique and go with that. Again thanks and regards Don. P.S thanks to all the folks whom have responded to my concerns.VTTEVW