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[glyn44]

im ready to start to apply a finish to a mahogany boat. I not sure if I should apply sanding sealer and then varnish. Or if the top surface should just have the vanish only applied.
Regards Glyn.

[Brian60]

Everyone will have their own ideas on how to go about it.

Personally I dilute varnish 3 parts diluent 1 part varnish and apply two coats so that it soaks into the surface. Then I sand back to remove the rough surface/ raised grain. Then start to build up coats of varnish, brushing 3 coats with finer sandpaper between coats. If I'm spraying then as many coats as I feel necessary to give the finish I want.

[chas]

Brian's right, everyone seems to have there own ideas. For what it's worth, I do exactly the same as him, it's a tried and tested method and been used for many many years. Sometimes I've put many many coats on until I'm happy with the finish, but 3 or 4 usually does it. The most important thing is cleanliness, as with any finishing job, patience is good too.

[Jerry C]

For a model I use 3 coats of shellac type sanding sealer. It drys in ten minutes. After each coat I rub down with medium or fine wire wool. Next two coats of 9:1 yacht varnish:white spirit. Rubbing down first coat after two to three days with fine wire wool. Never needed a third coat. For a full size narrowboat brightwork I brush on a liberal layer of white spirit. This draws first coat of thinned varnish 1:1 into the wood. Rub down with medium wire wool after two days. Then I apply up to ten coats of 9:1 rubbing down each coat with fine wire wool. Difference is that the narrowboat gets really hammered by the elements and uv light.
Jerry.

[glyn44]

Ok guys,
Are you saying I'm to dilute my varnish with white spirit ?

[Jerry C]

Kind of, yes. 9:1 thins the varnish quite a lot and lengthens the drying time and gives more time for the brush marks to settle before varnish skins over. Don't be tempted to put on thick coats. The beautiful smooth finish you are hoping for comes about by all the flatting down between coats.
Jerry.

[chas]

A perfect example of us all having different ideas of what's best. For me, 9 to 1 is excessive, 3 to 1 is fine, and yes, white spirit for a normal varnish. I don't use acrylic varnishes for this type of job.

[derekwarner]

No the image below is not a urine sample for my Doctor .......but..in Australia we take an ISO Metric determination for thinning of bases...yes we talk about dilution

My example is a dilution of Cabots oil based polyurethane.....

I use ten parts of Turpintine fluid to one part of Polyurathane .....

So we say    10:1....this way there is little confusion...apart from the fact we now have a bottle that has eleven parts in it   

Between Jerry & chas...the words don't quite fit the degree of dilution 

Derek

[glyn44]

Nice one guys. I haven't as yet bought any varnish, so I'll buy appropriate thinner when I do. Can I be bold and ask another Q please? How much movent should there be on a rudder ? Say from its neutral position should I aim for 30*,45* left and right, or even more.
Regards, Glyn

[dougal99]

Anything over 45 and it becomes a brake. The optimum angle depends on the size of your rudder relative to the size of the hull however, I would suggest somewhere between 30 and 40. Don't forget it's proportional, so you don't need to use full rudder all the time.

[glyn44]

Ok thanks for that

[Seacommander]

Finishing is the most difficult task of all.

My advice, what has been said already is very good, but work as clean as is possible. Work out what you are going to do and if you need to mask anything use Tamiya Masking tape. It will take a bit more time to work clean but save allot more in the end - Don't get disheartened if you don't get the result that you desire immediately, just keep plugging away. Also, come back for more support if required.

Best of luck

Mark

[glyn44]

Most kind Mark, I'm sad and sealing at the moment, oh just found a few parts missing from the kit. Brilliant!

[roycv]

Hi, agree with all above.  If you want a glass like finish spars and masts especially then finish with fine steel wool soaked in a hard polish, leave to dry and then polish with a cloth.  This is excellent for sailing boats as the cloth sails just float frictionless past the spars.
This was a tip given to me by Ken Impey many years ago when we used to write letters.
regards Roy

[Brian60]

I'll add the point everyone has neglected here. If you buy your varnish, polyurethane or whatever do check the labelling. A LOT of stuff nowadays is eco friendly ie, it dilutes with water and brushes are cleaned in water. It's not very good if you try an dilute that stuff with turps/white spirit, its water based! This is especially the case if you buy in places like B&Q. They do keep spirit based varnishes but very few usually hidden away on the shelf with specialist finishes like speckle or crackle spray paint.

[nemesis]

Nobody has mentioned that polyurethane is quite hard and does not expand  the same as wood. Will tend to crack, let the moisture in and go cloudy. Yacht varnish is formulated to expand and contract with the wood. nemesis

[Onetenor]

Anything over 45 and it becomes a brake. The optimum angle depends on the size of your rudder relative to the size of the hull however, I would suggest somewhere between 30 and 40. Don't forget it's proportional, so you don't need to use full rudder all the time.

Speed of model also has a bearing on it too

[roycv]

Hi all, I bought some gloss yacht varnish a week ago in the Poundshop!  Under the name of Tommy Walsh and 175 ml in a tin.  The instructions are to use white spirit for cleaning.
It looks like varnish as we are used to and I used some a day or so ago and the results are good.  I prefer to use this sort of size as I generally lose a third of the contents through intermittant use.
I shall buy another tin now for the future.
I have used a water based outdoor varnish, looks white dries clear.  That seems alright but decided against using on a boat hull.
When finished with a tin but some still left over, I put the lid back on firmly and store upside down.  I think it stops the drying film from forming, any one else tried it?
regards Roy

[KeithH]

The Tommy Walsh stuff in Poundlands is good.  I don't think TW would put his name to rubbish

I haven't seen the varnish but the superglue is good and it stays useable quite a few days after first piercing.

I bought a Tommy Walsh 10mtr tape measure and a claw hammer for a quid each.  Ideal for light hobby stuff