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[MikeA]

i planning my next hull and i want to seal the hull with the dope and tissue method. i know what tissue is but whats dope is that grp resin?

[nhp651]

it's a cellulose based sealer similar to sanding sealer that shrinks when drying and forms a hardened  film within the tissue......used mainly by the aircraft lads on fuselages and wings for lightness......totally different to polyester resin used in grp laminating.

[MikeA]

theres a post on here of bluebird making a model of a perkassa and he uses it on that. Ive done grp laminating in the past. Ill give it a go. my current boat is sealed with sawdust and cyanoacrylate glue. then painted twice with 4 coats of laquer on top. it seals but the finish looks like dog faeces.   

[tigertiger]

I think there may be an issue with CA and water. Not sure but there is a bell ringing in my memory somewhere.

I have used sawdust and varnish before.

[unbuiltnautilus]

theres a post on here of bluebird making a model of a perkassa and he uses it on that. Ive done grp laminating in the past. Ill give it a go. my current boat is sealed with sawdust and cyanoacrylate glue. then painted twice with 4 coats of laquer on top. it seals but the finish looks like dog faeces.   

I have used Cyano and sawdust as a re-enforcing INSIDE models with great success, outside, it may look more like doggy doo doo as you so eloquently put it! Dope is usually used for shrinking tissue onto aircraft fusalages and is ideal ( along with its stablemate Sanding Sealer ) for sealing and waterproofing timbers. However some suppliers are steering away from the traditional cellulose based sealers towards a water based alternative, the latest being Ezee Dope from deluxe Materials. My first thoughts were of panic as another useful product was withdrawn due to the evil components that go into its make up ( they use puppy dog tails to make it!!  NOT ACTUALLY TRUE ), however, having painted some of this onto balsa wood and then dunking it into a cup of water for two hours it seems to hold up well with no change of colour or toughness. Its still not fair though, who doesn't like the smell of cellulose dope drifting rapidly through the entire house?

[MikeA]

well the glue seems to have held on all my models so far. Its not like my boats spend weeks at a time moored up in a mariner either. I want to use this dope idea but i dont know where or what to look for now if its all changing. I would use grp but its not cheap and im a budget boat builder.

[malcolmfrary]

If you associated the dope as being something like resin, be aware that tissue, in this case, is tissue paper, not the thin glass strand sheet from the car body repair shelf at Halfords.
Properly done, dope and tissue over balsa gives a finish like silk, and almost as tough as sheet metal.  And that nice smell....   It also seems OK with any kind of paint, except water colour.

[MikeA]

i woudlve bought the glass type tissue if ya hadnt spoke up 

[John W E]

hi there

you must, first of all, tell me where and when I have built a Perkassa? Go to a dark room and write 50 times Bluebird hasnt built a Perkassa YET but he has built a vosper MTB

On a serious note, I think all of your queries have been answered with the other postings with regard to tissue & use of dope etc.

If you are still unsure, click onto the Fairey Swordsman for Beginners Questions and Answers in the masterclass build section of this forum and half way down a guy who used to be called FLJ (ph l j) PUTS A LINK on in respect of a write up which was published in Model Boats magazine and also on this forum.   He discusses the use of how to apply tissue to a hull using dope, thinners and soforth.

aye
john e
bluebird

[MikeA]

pfft technicalities

[tobyker]

Only downside to dope is that it takes a long time to go off and the vapour is a. heavy and b. highly flammable. Having finished doping a balsawood r/c pop-pop boat the night before a vintage yacht rally at Bournville and conducted the trials at the meeting the crowd were thrilled by the sight of the hull turning brown and the tiller ropes burning through. Luckily the Tx had a long aerial and the r/c survived the dunking!

[MikeA]

how did it catch fire?!?!

[malcolmfrary]

how did it catch fire?!?!

Google can be your friend.  It was a pop-pop boat.  After reading the links you will realise that this implies a naked flame.

[MikeA]

i see not suprised then.