stunthanger.com
Building Tips and technical articles. => Building techniques => Topic started by: steven yampolsky on June 25, 2007, 12:12:06 PM
-
I've been reading about how West Coast guys have been Randolph nitrate dope with great success. I looked for it on Aircraft Spruce and it looks like the price is pretty decent, especially in 5gal jugs. One problem: there are 4 different kinds of Randolph Nitrate dope:
http://www.aircraftspruce.com/catalog/cspages/randnitratedropclrhi.php
http://www.aircraftspruce.com/catalog/cspages/randnitratedopeclr.php
http://www.aircraftspruce.com/catalog/cspages/randnitratenontaughtclear.php
http://www.aircraftspruce.com/catalog/cspages/randnitratenontaughttinted.php
Which one do I get? Help!
-
Hi Steve.....
I believe that the left coasters are using nitrate to stick carbon and tissue to wood....it is allegedly lighter that buterite but not fuel proof....
Brodak uses Randolph dope but mixes it to more fully agree with what we are trying to accomplish.....
-
Steve,
I have been using Randolph's Nitrate since Bobby Hunt turned me on to it in 1993. For all substrate, and attaching CF veil, silkspan, silk, Jap tissue, or polyspan, I use the 'Non Tautening Tinted" which Bob recommended. It thins with Dupont 3608S, no problem.
http://www.aircraftspruce.com/catalog/cspages/randnitratenontaughttinted.php
I go to butyrate dope to shrink and fill. My last Classic plane used no filler at all. Just tinted "n/t" Nitrate. Very light, and it filled all the grain, etc., as good as using a filler.
Do NOT buy it in gallons or more, unless you plan on picking it up yourself. Buy it in quarts. It is more per quart compared to per gallon, but the shipping is about 1/10th the cost! For whatever reason, the quarts do not have the extra charges tacked on that goes with gallons or more. The extra dollars will be made up many times over in the erduced shipping cost. Plus, you can open a quart at a time. This was from Aircraft Spruce, directly. Get a quote from them about this.
Oh, yeah, covering is easier to apply with nitrate, it is "stickier'! That IS the truth!
This was a "nitrate base" plane, no filler:
-
allegedly lighter that buterite but not fuel proof....
Well, you don't need fuel proof unless you go electric or diesel n~
-
I have been using Randolph's Nitrate since Bobby Hunt turned me on to it in 1993. For all substrate, and attaching CF veil, silkspan, silk, Jap tissue, or polyspan, I use the 'Non Tautening Tinted" which Bob recommended. It thins with Dupont 3608S, no problem.
Thank you for the info Bill! I have looked at the link you provided and it says that it take longer to dry than regular nitrate dope. How does it compare to, say, SIG equivalent in terms of drying time?
-
Thank you for the info Bill! I have looked at the link you provided and it says that it take longer to dry than regular nitrate dope. How does it compare to, say, SIG equivalent in terms of drying time?
I think the "drying time" is for full size aircraft work. In model usage, I haven't really noticed a difference between it and Sig Nitrate. When I run out of Randolph's, I have to get the Sig, whic also works just fine. But you cannot get the tinted non-tautening Nitrate from Sig. The n/t nitrate just doesn't shrink as much (it still shirnks a *little*) and the "tinted" part helps you see how much you are building up and if you are missing spots.
As far as fuel proof, that comes from what ever you put over it: Butyrate color, Auto basecoat/clearcoat, or whatever.
JUST REMEMBER! Do not use nitrate over butyrate (it can really ruin your day! LOL!!)! But everything goes over nitrate.
-
Can someone tell me the difference between nitrate and butyrate? I really have no clue n~ **)
-
Neither one is really fuel proof, but nitrate is more honest about it.
-
Can someone tell me the difference between nitrate and butyrate? I really have no clue n~ **)
Chemical composition. Not much else to say. :D Nitrate is nitrocellulose lacquer. Butyrate is also a lacquer, but I cannot remember exactly what the "Butyrate" stands for! LL~ LL~
Good nitrate dope will plain eat up most butyrate dopes. But the butyrate doesn't harm the nitrate. So, to me, something is less "hot" in the butyrate. Different solvents used to dissolve the solids, I suspect.
-
If I remember right from A&P school butyrate is cellulose-acetate-butyrate or CAB.
-
If I remember right from A&P school butyrate is cellulose-acetate-butyrate or CAB.
Hi Crist,
That is what I have always heard it referred to, I just could not remember it! LOL!!!!!!!!
-
I know it sounds crazy, but I'm sure I've read somewhere about people making their own dope by dissolving CD cases in...something. Acetone? I guess the plastic is acetate.
Just a little human interest note.
--Ray
-
Not at all crazy. Back when models had bamboo wing tips and rubber for power and there was a serioius lack of money, modellers would dissolve toothbrushes and photo film in acetone to make glue. Both were celluloid then.
Model builders are a most inventive sort of person.
-
Not at all crazy. Back when models had bamboo wing tips and rubber for power and there was a serioius lack of money, modellers would dissolve toothbrushes and photo film in acetone to make glue. Both were celluloid then.
Model builders are a most inventive sort of person.
Actually at $32 a gallon, we could just as well buy NEW toothbrushes and film to disolve.
-
Actually at $32 a gallon, we could just as well buy NEW toothbrushes and film to disolve.
Actually, at ~$40/gal it's a very good deal considering that a quart of SIG Nitrate is $17. I used Heros Aviation(http://www.herosaviation.com/) instead of Aircraft Spruce. The problem with Aircraft Spruce is that they charge HAZMAT fees while Heros Aviation does not.
-
I've been reading about how West Coast guys have been Randolph nitrate dope with great success. I looked for it on Aircraft Spruce and it looks like the price is pretty decent, especially in 5gal jugs. One problem: there are 4 different kinds of Randolph Nitrate dope:
http://www.aircraftspruce.com/catalog/cspages/randnitratedropclrhi.php
http://www.aircraftspruce.com/catalog/cspages/randnitratedopeclr.php
http://www.aircraftspruce.com/catalog/cspages/randnitratenontaughtclear.php
http://www.aircraftspruce.com/catalog/cspages/randnitratenontaughttinted.php
Which one do I get? Help!
Hi Steven
NONE of the above
this is the one that I have used for many years:
Randolph Nitrate Dope Clear High Solids
This is the premium clear nitrate dope from Randolph specifically formulated for applications requiring hi-solids. Very durable.(Not for use on Ceconite fabric).
View more details
210-QT RAND NITRATE DOPE # 210 QT $12.75 Request Quote
210-1G RAND NITRATE DOPE # 210 1G $38.35 Request Quote
210-5G RAND NITRATE DOPE #210 5 GAL $184.65 Request Quote
This dope works very well to put on CF mat or paper and fills a little too so you get a smoother base to finish faster
Randy
-
Hi Steven
NONE of the above
this is the one that I have used for many years:
Randolph Nitrate Dope Clear High Solids
This is the premium clear nitrate dope from Randolph specifically formulated for applications requiring hi-solids. Very durable.(Not for use on Ceconite fabric).
View more details
210-QT RAND NITRATE DOPE # 210 QT $12.75 Request Quote
210-1G RAND NITRATE DOPE # 210 1G $38.35 Request Quote
210-5G RAND NITRATE DOPE #210 5 GAL $184.65 Request Quote
This dope works very well to put on CF mat or paper and fills a little too so you get a smoother base to finish faster
Randy
Ok, there, ol buddy, ol friend, ol pal, ol buddy, ol friend! **)
I guess I will try that type of Nitrate, but I have been very happy with the "non-tautening tinted" that Sir Robin of Hunt gave me the tip for about 15 years ago. It has had plenty of "solids", so far......... My Argus had zero perceptable flaws in it and only used the above mentioned Nitrate for everything (including filling) except shrinking the silkspan. That was one plane that I really spent time putting a finish on! LOL!! What wasn't damaged during the flame out crash still has shown no signs of grain popping out after about 5 years.
But having more "solids" can only be a good thing, right?? **)
Thanks for the tip, I will get me some of the high solids.
-
Here's a dumb question, why don't you guys use butyrate dope? I used to use the nitrate up until color, for the last several years I have just used butyrate. Reason question is dumb, can't remember why I used nitrate before butyrate, just getting to old. Have a great day, Gary
-
Hi GAry,
Just persoanl preferences I guess! Nitrate sticks covering down easier for me and fills quicker.
Many people, including Windy, just use butyrate. Billy Werwage used to use only Aerogloss clear for the substrate then on to butyrate. Just what we get comfortable with, I guess.
-
Hi Bill, thank you for your answer. One of the reasons I use butyrate only is, because my son and I seem to forget to mark which dope is nitrate or butyrate. Seems to me nitrate draws tighter, but they both work and if you pull the silkspan tight when you're working, butyrate seems to work okay for me. I do my silkspan the dumb way, clear dope on the wood, several times, cut silkspan about an inch larger. Than I lay silkspan over area then I wet it, seems to work better. Years ago my dad helped us cover our planes and he would have a tub of water that we would draw the silkspan through and then place it over the area we where covering. Sometimes would end up with a mess because silkspan would fold and can be hard to straighten out after it is wet. Great memories working with my dad on our toys. Have a great day and thanks for being here to help all of us, Gary
-
Hi Steven
NONE of the above
this is the one that I have used for many years:
Randolph Nitrate Dope Clear High Solids
This is the premium clear nitrate dope from Randolph specifically formulated for applications requiring hi-solids. Very durable.(Not for use on Ceconite fabric).
View more details
210-QT RAND NITRATE DOPE # 210 QT $12.75 Request Quote
210-1G RAND NITRATE DOPE # 210 1G $38.35 Request Quote
210-5G RAND NITRATE DOPE #210 5 GAL $184.65 Request Quote
This dope works very well to put on CF mat or paper and fills a little too so you get a smoother base to finish faster
Randy
Hi Randy,
I used to buy my dope from the local airport repair shops. The clear dope I used to get from them was as thick as honey, used a lot of thinner to get it thin enough to spray. Is the 210-qt clear thick or is it more like Brodak or Sig dope? I order some today and was just curious which way the dope will come (thick or thin) either way will be good, just hope it comes thick so it will go a lot farther. Thank you, Gary
-
The difference in shipping is because for some odd reason, there are no hazmat fees on quarts. So you save $20 per package if yo ubuy things in quarts.
One fuel company (Red Max IIRC) actually ships their fuel in quarts and provides a complementary gallon jug for every 4 quarts. :)
-
When Pete Peterson's article on clear finishes come out in SN, youse guys will be beating a path to the nearest Randolph dealer. I asked Pete about the final topcoats, since Brodak clear is reputed to be less fuel proof than SIG. He said Randolph's Butyrate Clear is as fuel proof as SIG Clear and way more fuel proof than Brodak clear. I don't know if Brodak's formula has since been revised or not, but it's a known fact that Randoph also makes SIG dope and makes Brodak dope, but Brodak wanted some reformulations for some reason not clear. Uh...no pun intended. Well, maybe intended just a Little. Pun intended! LL~ Steve