WBPU and talc mix is awesome. It is very light and sands down very smooth. It will fill all the gaps very well and leaves a very smooth finish. You can use different mixes with it, I go from a fairly viscous consistency to fill the weave on fg right up to a peanut butter kind of paste. Play around with it until you find the mix that suites but use it as thin as possible.

Originally Posted by darook

WBPU and talc mix is awesome. It is very light and sands down very smooth. It will fill all the gaps very well and leaves a very smooth finish. You can use different mixes with it, I go from a fairly viscous consistency to fill the weave on fg right up to a peanut butter kind of paste. Play around with it until you find the mix that suites but use it as thin as possible.

Thanks! Any particular brand of wbpu you recommend? I've never used the stuff before.

Minwax

hey! You just answered my ?, Im building a Nacelle for my 80mm deltav32 and was looking for somthing lighter than bondo.

Excellent, I am picking some up on my way home tonight.

Minwax works great, Im sure that other brand polys would be fine too as long as they are water based. As far as I can tell those motors should be fine on 4s, looking at the specs. The units I have are the Detrum 70mm combos from Hobbypartz, for about 50 bucks they seem to be a great deal They perform great on 4 or 5s, I havent tried 6s yet but I have seen where people have. I might give it a go

Guys, the poly/powder mix is great, I use it quite a bit but, be careful it can add the weight fast.. Experiment on scrap with different amounts of powder, to get it where you like it.. Then, apply first coat, let dry, sand, second coat, sand with finer grit. You'll find this stuff not only fills but makes a super slick finish to apply your paint to... Good luck!w

Originally Posted by Lt599

Minwax works great, Im sure that other brand polys would be fine too as long as they are water based. As far as I can tell those motors should be fine on 4s, looking at the specs. The units I have are the Detrum 70mm combos from Hobbypartz, for about 50 bucks they seem to be a great deal They perform great on 4 or 5s, I havent tried 6s yet but I have seen where people have. I might give it a go

Excellent, I need to look at those motors. I wonder what the amp pull will be. (upgrade my esc's)

Water based for the poly urethane is a must anything else could potentially dissolve the foam.

I have the same Detrum 70mm combos and tried both 4S and 5S, but 6S sounds crazy I've put these fans on a watt meter and it will draw 33amps and 54amps on 4S and 5S, respectively. So I'm guessing it will be well beyond the ESCs rated amps once you go to 6S. Also people on this forum who are using this combo on 5S suggest that before you do that that you balance the fans, which I have...just to be sure.

Originally Posted by Waltjg

Guys, the poly/powder mix is great, I use it quite a bit but, be careful it can add the weight fast.. Experiment on scrap with different amounts of powder, to get it where you like it.. Then, apply first coat, let dry, sand, second coat, sand with finer grit. You'll find this stuff not only fills but makes a super slick finish to apply your paint to... Good luck!w

Thanks for the adding info Walt! I picked up a can on my way home last night and applied a "paranoid" thin layer later on my fuselage. I really like the take so far. It also seems to dry nice and fast.

I did have a hard time getting the talc to mix properly. Some general questions if anyone can help...

1. It seems like it would take a lot of talc to make it "thick". I'm wondering what the recommended ratio is for a "general" cover mix. It just seemed like its going to take a lot of talc so maybe that's normal.
2. Is there any need to thin the wbpu? If so do you thin it with water?
3. Are there mix options other than talc that can be substituted? I've heard of corn starch but I wondered about experimenting with thinned LWS.
4. Does the finished product leave a protected shell over the foam to help prevent pits and dents? Or is that too thick? (I guess that depends on ones weight concerns)

Thanks everyone for the help!

B, yes, it seems like it takes alot of talc, and make sure it is talc and not cornstarch based... No don't thin it... It does offer a small amount of protection but will still dent and scratch. w.

Excellent job on the Hawg. I do also recommend going to the servoless retracts but you want to really reinforce that you're mounting them to. one hard landing and you'll drive them through the top of the wing or fuse.

What airfoil are you using? I have my plans scaled and printed but I cannot decide on the airfoil. The full size plane uses a NACA 4616 at the root and 4613 at the tip. I have printed these out along with the 4212 and Clark Y. The scale airfoil as a very unique shape. It is quite thick and has a negative sweeping TE. I am just not sure if I can get away with the scale airfoil on the model,my WS is 50" . Any thoughts? Im ready to start cutting Greg

Originally Posted by Lt599

What airfoil are you using? I have my plans scaled and printed but I cannot decide on the airfoil. The full size plane uses a NACA 4616 at the root and 4613 at the tip. I have printed these out along with the 4212 and Clark Y. The scale airfoil as a very unique shape. It is quite thick and has a negative sweeping TE. I am just not sure if I can get away with the scale airfoil on the model,my WS is 50" . Any thoughts? Im ready to start cutting Greg

Hey Greg! I went with a vanilla clark y. Works awesome. Takes off and flys very stable. I also was going to use the scenario you mentioned above. But it just seemed too thick for what I wanted to cut and I ended up not wanting the hassle. Its doable but I just felt more comfortable with the clark y.

I'll post some updated pics by Saturday (should have a rough coat of paint). Its taken apart right now for wbpu and is looking good. I had to sand all the darn latex paint off because it looked terrible and seemed too heavy. Let me know what you decide to go with.

Originally Posted by Waltjg

B, yes, it seems like it takes alot of talc, and make sure it is talc and not cornstarch based... No don't thin it... It does offer a small amount of protection but will still dent and scratch. w.

Thanks again Walt... the wbpu and talc works great. - Brent