Brodak nitrate dope

I saw Brodak brand of Nitrate dope in a hobby shop. I thought Brodak only made Butyrate. Can I use the Nitrate for sticking down the tissue, then use Butyrate over it for the color? There has been a lot of posts saying that we should stick to 1 type of dope to prevent problems, like stick with Butyrate all the way. Anybody use this combo? Of course, I'll use only Brodak thinners and retarders.
Thanks

A lot of people do what you suggest--use the Nitrate to stick down the silkspan because they think it sticks better of fills better. I, personally, do not loke using Nitrate first because if you do get fuel underneath it can unstick things and make a mess. Remember, Nitrate is not fuel proof. However, there will be no problem using Brodak or any Nitrate as a base and then putting Brodak Butyrate over it. It would be very wise to use Brodak thinner throughout, as this becomes the common bonding agent.

Leonard Neumann

I ended up with some Brodak nitrate by mistake, and like it just fine. Full scale aircraft recoverers use nitrate as a base because it sticks better to Grade A cotton cloth. The Brodak filled nicely and made a nice base for the butyrate. I have yet to see any of the oil soak problem Leonard mentions, but that is always a possibility. I think that a good quality butyrate job over the the nitrate would do pretty well.

It is nice to use the Nitrate on all of your under coats such as the first coats prior to covering and during covering and a few coats afetr covering. A couple of good reasons is that it has no Gloss hardener in it. That means to things. When thinned it will penatrate better. This means sticking down covering like polyspan is easier. The second thing is that without the Gloss hardener it is much lighter than Butyrate. When it fully gasses off(25 to 30 days) you wont see any weight gain on your scale. You can use nitrate and stirate filler additive and some thinner and spray coat after coat after coat and after the full dry time you will have add little if any weight and you will have youe plane filled. Then the first coat of butyrate sanded will be nice and shinny and you can start painting from there. To get the full benefits of it being light you will need to wait before you put on that first coat of butyrate for the nitrate to fully gass off.

Doug Moon

This means sticking
>down covering like polyspan is
>easier. The second thing
>is that without the Gloss
>hardener it is much lighter
>than Butyrate. When it
>fully gasses off(25 to 30
>days) you wont see any
>weight gain on your scale.
> You can use nitrate
>and stirate filler additive and
>some thinner and spray coat
>after coat after coat and
>after the full dry time
>you will have add little
>if any weight and you
>will have youe plane filled.
>Doug Moon

Doug you need to learn to spell, really.
Second, Sig nitrate gets quite shiny, maybe less than butyrate, but wet sanded flat is much like a topcoat.

My weight numbers for my new plane go like this.

Foam wing halve (Time Machine):
Core with spar = 2.2 OZ.
Balsa Sheet = .7 OZ wood, .9 OZ joined
Sheeting glue = .1 OZ per sheet
Core sheeted (no leading or trailing edges) = 4.2 OZ
With leading trailing edges added = 4.7 OZ
With Stiletto style wing tip built “Tom Morris” style (fully sheeted-very nice) = 5.0 OZ
3 coats of wiped Minwax Polycrylic (sanded between) = 5.2 OZ
Ultra light Jap tissue (one layer) and (4) coats of 50% nitrate clear dope (not sanded) gased off for one week= 6.2 OZ
Dope sanded flat and shiny = 5.8 OZ

I disagree that nitrate has no weight. It does on my scale. I will continue to let these coats gas off, but I bet they do not get any lighter.

Nitrate is the universal undercoat. Everything sticks well to it. It is definitely the way to go for BASECOAT/CLEARCOAT. I use lacquer thinner from the automotive store; Brodak stinks a lot and is very expensive.

If you use DOPE for finish, ignore everything I say. I do not use dope, and I have no knowledge of its use.