What brushes for dope?
 

Just for the fun of it, I'm going to cover a Kadet Seniorita with silkspan and dope (nitrate, then butyrate). What kind of brushes should I use? Does it matter whether they're made with artificial or natural bristles? I haven't done this since I was a kid, and that was quite a qhile ago.

RE: What brushes for dope?
 

The last time I doped a plane, about 40 years ago, I used Camel hair brushes. It took a while to get all of the stray strands out. I don't know if you can still get them or not.

A friend of mine that dopes all his planes even now and buys dope by the 5 gallon cans, is using the throw away foam brushes. They were not around when I doing dope (Paint dope that is).

RE: What brushes for dope?
 

I use natural hoghair brushes, they seem to leave the dope smoother (less brushmarks) . I buy the cheap ones at Lowe's and they will last long enough to do a plane before the bristles start coming out in handfuls (not really that bad:) ). They will still shed a few when you first start using them.

RE: What brushes for dope?
 

I use good quality camel hair brushes that I bought at an art supply store over 20 years ago... I expect they'll last as long as I will :)

For silk I will use the foam brushes for the first couple of coats until the weave begins to fill but I don't need them for silkspan.

One trick that will help is to run a little thin CA along the ferule prior to use- this will prevent most occurences of losing bristles with the cheapy brushes.

Although I've been guilty of it myself, I wouldn't recommend silkspan for a Seniorita. That nice stick built open structure would leave the silkpan very suceptable to punctures. Silk is a better (though more expensive) choice, but there are places that sell model grade silk at much better than hobby shop prices.

RE: What brushes for dope?
 

I haven't used silkspan in years, but I use Koverall and dope exclusively on my Waco's. I put the Nitrate on with a cheap Chip Brush, and then lightly sand with 400 grit, and that removes the stray bristles. I finish mine with spray equipment (HVLP) and normally use Automotive Base Coat/Clear Coat for the final finish.

Bill, AMA 4720
WACO Brotherhood #1

RE: What brushes for dope?
 

Thanks for the help, guys! Lotus72D, I've never used silkwhat do you need to look for when you buy it?

RE: What brushes for dope?
 

Top Gunn: Silk is a whole nother skill set.

https://www.modelaircraft.org/Member...ge_article.htm

October 1993

More than worth the time to download and read. I still refer to it when I have not done silk for a while. Extroadinarily labor intensive, BUT, you end up with a finish that is equalled by none.

http://www.thaisilks.com/product_inf...products_id=11

Silk at $2.95/ yard. You don't need to pay the hobby silk prices.

Les

RE: What brushes for dope?
 

TG, unless you really want the silkspan for the whole old time experience, I would recommend Polyspan or Koverall. I remember a lot of punctures in my old silkspan CL planes, and I would not go back to it.

Polyspan looks a lot like silkspan, but it is a synthetic. It takes dope well, but doesn't soak it up like silkspan does, so it seals quicker. It can be stretched around compound curves. It is not great at going around curves, but I have had good luck with it using an iron and pulling on it. Heat will soften dope, so you can actually iron it over carved wing tips if they are doped first. It is heat-shrinkable, and very tough. It is much lighter than Koverall (although Koverall is not terribly heavy); it would be hard to come up with a strong covering as light as doped Polyspan.

Silk is available, but either you pay for it like gold leaf or you get the pre-shrunk fabric type that is hard to shrink.

Jim

RE: What brushes for dope?
 

I too use Camels hair brushes, I should say brush since the one I use is over 20 years old.
My new one is still in the package.

The CA to help keep the brush from shedding is a great idea.

Before CA I'd dip the brush in straight clear dope. Then wipe the excess, and let the brush stand on the handle end till the dope was dry.
This would seal the hairs into the metal frame.

I haven't had any drip problems with the camels hair brushes. I super thin the first coats of dope, and hold the open structure so the silk is vertical.
Then give the silk a few coats of dope.

Thai silk is a good place to get silk.

Here is another one. http://www.dharmatrading.com/html/en...bric_silk.html

Looks like the same stuff as Thai Silk offers.

I have noticed the silk from there doesn't shrink neary as much as the old silks used to.
The dope on this wing was applied with a brush.
Just clear over dyed silk.