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General control line discussion => Open Forum => Topic started by: Ken Culbertson on December 08, 2022, 06:06:43 PM
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I just did a test of using Mod Podge to seal the wood before applying MonoKote. The MonoKote stuck like a second skin. This is not what I expected. Has anyone else tried it? I normally do not put anything under monokote.
Ken
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I had an apprentice who decided to use it to stick passages of the Bible on his Strat and then clear coat it. It worked very good, which tells me it's a fairly good adhesive used in the right place. Likely it works like titebond when heated and melts somewhat to cause the better stick.
I'd say you just navigated new and friendly waters! H^^
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Ok, I'll bite. Why would you need an adhesion promoter for Monokote?
There's a product thats been avaliable in the UK and Aus called Balsaloc which looks suspiciously like PVA, and that's supposedly a heat activated adhesive. I wonder if it's not just Mod Podge or a similar derivative.
I preferred Balsarite when I could get it but supplies in Australia dried up long ago.
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Ok, I'll bite. Why would you need an adhesion promoter for Monokote?
There's a product thats been avaliable in the UK and Aus called Balsaloc which looks suspiciously like PVA, and that's supposedly a heat activated adhesive. I wonder if it's not just Mod Podge or a similar derivative.
I preferred Balsarite when I could get it but supplies in Australia dried up long ago.
Monokote doesn't stay stuck very well on the whole plane over time and it is really hard to cover fillets. I have used Balsarite and it is not much better. This was different. I had three coats of Mod Podge sanded like you would dope. Really smooth which is not good with monokote. The bottle says it takes 28 days to cure. I wonder, during that period if it is sensitive to heat OR and this is more likely, there is some kind of chemical reaction to the MonoKote's glue.
Ken
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Time will tell I guess, let us know your findings!
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i would advise to avoid sealing, as monokote under sun liberates gas from the adhesion material endless. if sealed the air canīt go anywhere and may develop riddges hard to iron back and even delaminate on the sealed areas. the monokote sealing properly done is good enough to keep it there and from time to time if needed you can use the heat gun to shrink it back. i have covered about 100 r/c planes and tried everything, my only regret was sealing one before applying.
600 grit sandpaper and a full blow of air will be enough to have a good surface adhesion
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I start with sanding smooth then use the pecker tool to give gas off relief, not hole just run it over the suface. I then apply one coat of Balsarite for film to the balsa let it gas off for a few days then apply file. This gives a strong bond that stays put even in the sun. I like the Ulta-Coat material as it seems more resistant to loosening.
Best, DennisT
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i would advise to avoid sealing, as monokote under sun liberates gas from the adhesion material endless. if sealed the air canīt go anywhere and may develop riddges hard to iron back and even delaminate on the sealed areas. the monokote sealing properly done is good enough to keep it there and from time to time if needed you can use the heat gun to shrink it back. i have covered about 100 r/c planes and tried everything, my only regret was sealing one before applying.
600 grit sandpaper and a full blow of air will be enough to have a good surface adhesion
Thanks - I am going to follow your advice.
Ken
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i would advise to avoid sealing, as monokote under sun liberates gas from the adhesion material endless. if sealed the air canīt go anywhere and may develop riddges hard to iron back and even delaminate on the sealed areas.
One of my best glider flights was about 30 years ago with a Goldberg Electra. I launched it on a hot day, and after getting a couple hundred feet up it just took off. It was just a speck up in the sky, and I had to give it a turn command and wait 20 to 30 seconds to see which way it turned so I knew its orientation. I was up for about an hour and a half when I had to bring it down. When it got on the ground, the covering was all puffed up. I had only sealed the edges of the wing and the heat and outgassing filled the wing with no way of escape. I guess the new airfoil section it got from being puffed up made it super efficient or something, as I wasn't thermal hopping or anything. I don't know how high it actually was, but the reason I had to bring it down was that we shared the field with ultralight planes and skydivers. Obviously, when one or the other group was up we stayed grounded. But on this day the skydivers took off from the B'ham International Airport, about 15 miles away, so we had no clue they were coming. The first warning we had was when a plane way up high cut its engine back and the little dots falling from the plane. As soon as we saw that, I gave full up and full right to spin down as fast as I could.
After we packed up for the day so the jumpers could have the field I went to the local convenience store to get a Coke. A couple of the skydivers were there getting goodies and one asked if I was one of the model plane guys. When I said I was he asked if I know who owned the blue and white plane. My glider was blue and cream, but I just said, "Yeah, I think I know him". The jumper told me to tell the owner that he passed the plane at 2,500 feet on his way down...
Not control line related, but an interesting anecdote that I just remembered. After that flight I sealed the covering down good and made a hole for the air to escape. Never had that good a flight again.
Mark