Hard wax v/s liquid wax

[FranCP]

Hi,
Can hard wax be replaced by liquid wax application? Of course silicon free, as well as other harmfull adds.
Although i've seen guys maintaining their gliders purely on applying liquid wax regularly, i guess it wont seal & protect the gelcoat as well as a good anual hard wax buffing.
¿Any advice?
Thanks

[[email protected]]

On Tuesday, August 28, 2018 at 8:30:22 AM UTC-4, FranCP wrote:
> Hi,
> Can hard wax be replaced by liquid wax application? Of course silicon free, as well as other harmfull adds.
> Although i've seen guys maintaining their gliders purely on applying liquid wax regularly, i guess it wont seal & protect the gelcoat as well as a good anual hard wax buffing.
> ¿Any advice?
> Thanks

Liquid wax is good for maintaining but is not a substitute for the sealing properties of hard wax on polyester finishes.
Hard wax buff, then maintain with liquid wax.
UH

[Soartech]

Please name a few brands and types of typical "hard wax" for use on gelcoat.
Thanks.

[Ross[_3_]]

Menzerna seems to be the pick of the bunch here in Europe
G18 first and something like M5 or P175 to give it a glossy finish

[Tim Taylor]

I have had good results recently with Big White Hi-Temp Paste Wax. Put in on thin by hand or smooth pad at low rpm with a random orbit machine. Let dry to a haze, hand wipe off with a clean cloth. Buff with a finishing pad at higher rpm.

As with painting, surface prep before waxing is critical for best results. Remove hard water stains (ehite viniger usually works), polish with an ultrafine compound like 3m Finesse-it II (white color). Be careful of the new 3M ultrafine compound for cars that is blue in color, it can stain white gel coat if left on the surface more than a few seconds.

[FranCP]

El martes, 28 de agosto de 2018, 12:27:55 (UTC-3), Soartech escribió:
> Please name a few brands and types of typical "hard wax" for use on gelcoat.
> Thanks.

According to my research, pure brazilian "Carnauba" seems to be good for the job.

[Tom BravoMike]

On Tuesday, August 28, 2018 at 10:41:06 AM UTC-5, Ross wrote:
> Menzerna seems to be the pick of the bunch here in Europe
> G18 first and something like M5 or P175 to give it a glossy finish

Generally, we believe that the smoother and more glossy the surface, the better. Is it actually supported by a scientific research? How about the 'stickiness' of certain substances with regards to the airflow, e.g. caused by electrostatic charge? Any thoughts?

[John Foster]

On Tuesday, August 28, 2018 at 6:30:22 AM UTC-6, FranCP wrote:
> Hi,
> Can hard wax be replaced by liquid wax application? Of course silicon free, as well as other harmfull adds.
> Although i've seen guys maintaining their gliders purely on applying liquid wax regularly, i guess it wont seal & protect the gelcoat as well as a good anual hard wax buffing.
> ¿Any advice?
> Thanks

A golf ball has many small dimples over its surface, to make it more "slippery". So how would this principle apply to a glider?

[Martin Gregorie[_6_]]

On Tue, 28 Aug 2018 19:50:19 -0700, John Foster wrote:

> On Tuesday, August 28, 2018 at 6:30:22 AM UTC-6, FranCP wrote:
>> Hi,
>> Can hard wax be replaced by liquid wax application? Of course silicon
>> free, as well as other harmfull adds.
>> Although i've seen guys maintaining their gliders purely on applying
>> liquid wax regularly, i guess it wont seal & protect the gelcoat as
>> well as a good anual hard wax buffing.
>> ¿Any advice?
>> Thanks
>
> A golf ball has many small dimples over its surface, to make it more
> "slippery". So how would this principle apply to a glider?

Read up on turbulators. They're not needed on modern airfoils, but were
useful for preventing flow separations on older wing sections (Wortmann)
and at the hinges of control surfaces:

- I've seen turbulators immediately ahead of the aileron hinges on
Discus 1s

- fitting them ahead of the rudder hinge on a Grob G.103 is said to
improve rudder response

- my Std Libelle has full span turbulators under the wing, just in front
of the undercambered part of the lower surface.
Streifneder sells them.

... and of course they work really well to improve airflow at low Reynolds
numbers (40,000 - 100,000).

Just ask any serious free flight model flyer. The first F1A I built with
a D-box wing structure flew like a dog until I fitted thread turbulators
where the rear of the leading edge and the front of the main spar were on
my previous successful open-structure models with entirely tissue covered
wings.


--
Martin | martin at
Gregorie | gregorie dot org

[Tango Whisky]

Le mercredi 29 août 2018 13:42:25 UTC+2, Martin Gregorie a écritÂ*:

> Read up on turbulators. They're not needed on modern airfoils,

Except that ALL modern airfoils use turbulators.

[OHM Ω http://aviation.derosaweb.net]

On Wednesday, August 29, 2018 at 7:20:29 AM UTC-5, Tango Whisky wrote:
> Le mercredi 29 août 2018 13:42:25 UTC+2, Martin Gregorie a écritÂ*:
>
> > Read up on turbulators. They're not needed on modern airfoils,
>
> Except that ALL modern airfoils use turbulators.

I am pretty certain that on my ASW-27B the only turbulators on the wings are small 2cm wide sections just in front of the underside NACA vents which pressurize the ailerons and flaps. I can only guess at the aerodynamics of the turbulator's purpose here but this might be an example of this particular modern airfoil NOT needing turbulators (per Schleicher at least). ;-)

Remind me - how did we get from talking about waxing onto the subject of turbulators? ;-)

[Martin Gregorie[_6_]]

On Thu, 30 Aug 2018 06:59:34 -0700, OHM Ω http://aviation.derosaweb.net
wrote:

> Remind me - how did we get from talking about waxing onto the subject of
> turbulators? ;-)

....via the Dimpled Golfball highway


--
Martin | martin at
Gregorie | gregorie dot org

[Tango Whisky]

Le jeudi 30 août 2018 15:59:36 UTC+2, OHM Ω http://aviation.derosaweb.net a écritÂ*:
> On Wednesday, August 29, 2018 at 7:20:29 AM UTC-5, Tango Whisky wrote:
> > Le mercredi 29 août 2018 13:42:25 UTC+2, Martin Gregorie a écritÂ*:
> >
> > > Read up on turbulators. They're not needed on modern airfoils,
> >
> > Except that ALL modern airfoils use turbulators.
>
> I am pretty certain that on my ASW-27B the only turbulators on the wings are small 2cm wide sections just in front of the underside NACA vents which pressurize the ailerons and flaps. I can only guess at the aerodynamics of the turbulator's purpose here but this might be an example of this particular modern airfoil NOT needing turbulators (per Schleicher at least). ;-)

Turbulators are either zig-zag / dimple tapes (all non-Schleicher), or blow holes (Schleicher). Both do the same job.

[Michael Opitz]

>I am pretty certain that on my ASW-27B the only turbulators on the
wings
>ar=
>e small 2cm wide sections just in front of the underside NACA vents
which
>p=
>ressurize the ailerons and flaps. I can only guess at the aerodynamics
of
>=
>the turbulator's purpose here but this might be an example of this
>particul=
>ar modern airfoil NOT needing turbulators (per Schleicher at least).
;-)
>

And what is the purpose of pressurizing the ailerons and flaps??
Could it be to actually pressurize the blow hole turbulators (which
some manufacturers have substituted Z-tape or dimple tape for
because of ease of construction and reduced maintenance
issues)????

RO

[[email protected]]

On Thursday, August 30, 2018 at 9:59:36 AM UTC-4, OHM Ω http://aviation.derosaweb.net wrote:
> On Wednesday, August 29, 2018 at 7:20:29 AM UTC-5, Tango Whisky wrote:
> > Le mercredi 29 août 2018 13:42:25 UTC+2, Martin Gregorie a écritÂ*:
> >
> > > Read up on turbulators. They're not needed on modern airfoils,
> >
> > Except that ALL modern airfoils use turbulators.
>
> I am pretty certain that on my ASW-27B the only turbulators on the wings are small 2cm wide sections just in front of the underside NACA vents which pressurize the ailerons and flaps. I can only guess at the aerodynamics of the turbulator's purpose here but this might be an example of this particular modern airfoil NOT needing turbulators (per Schleicher at least). ;-)
>
> Remind me - how did we get from talking about waxing onto the subject of turbulators? ;-)

Your glider uses blow turbulators, located at the proper point, which happens to be on the control surfaces.
To ensure full flow and pressure to the NACA inlets Schleicher puts double thickness zig zag tape in front of the inlets. This trips the flow to turbulent and ensures the effectiveness of the NACA inlets as a supply source.
UH

[John Foster]

On Thursday, August 30, 2018 at 8:37:17 AM UTC-6, Tango Whisky wrote:
> Le jeudi 30 août 2018 15:59:36 UTC+2, OHM Ω http://aviation.derosaweb.net a écritÂ*:
> > On Wednesday, August 29, 2018 at 7:20:29 AM UTC-5, Tango Whisky wrote:
> > > Le mercredi 29 août 2018 13:42:25 UTC+2, Martin Gregorie a écritÂ*:
> > >
> > > > Read up on turbulators. They're not needed on modern airfoils,
> > >
> > > Except that ALL modern airfoils use turbulators.
> >
> > I am pretty certain that on my ASW-27B the only turbulators on the wings are small 2cm wide sections just in front of the underside NACA vents which pressurize the ailerons and flaps. I can only guess at the aerodynamics of the turbulator's purpose here but this might be an example of this particular modern airfoil NOT needing turbulators (per Schleicher at least). ;-)
>
> Turbulators are either zig-zag / dimple tapes (all non-Schleicher), or blow holes (Schleicher). Both do the same job.

Which again comes back to the smoothness of the wing surface as it potentially relates to dimples in a golf ball. With a rough wing surface (from sanding?), would that have the same effect on the surface boundary layer potentially? Would there be a part of the airfoil that would benefit more from such a treatment? And thus, how important to polish the surfaces to a mirror finish?

[kirk.stant]

Didn't Dick Johnson run some tests on a Pik-20 that suggested that smooth but not polished was very slightly better than waxed to a mirror finish?

One would think that an Akaflieg would have looked at this in a wind tunnel.

My gut feeling is that the mirror finish doesn't really help, but is "expected", much like T-tails; but that if you can feel the roughness with your hand it will hurt the performance "a bit", whatever that is.

Anyway, it's more fun to win in a ratty looking glider than to lose in a perfect one ;^)

Kirk

[[email protected]]

On Thursday, August 30, 2018 at 2:59:36 PM UTC+1, OHM Ω http://aviation.derosaweb.net wrote:
> On Wednesday, August 29, 2018 at 7:20:29 AM UTC-5, Tango Whisky wrote:
> > Le mercredi 29 août 2018 13:42:25 UTC+2, Martin Gregorie a écritÂ*:
> >
> > > Read up on turbulators. They're not needed on modern airfoils,
> >
> > Except that ALL modern airfoils use turbulators.
>
> I am pretty certain that on my ASW-27B the only turbulators on the wings are small 2cm wide sections just in front of the underside NACA vents which pressurize the ailerons and flaps. I can only guess at the aerodynamics of the turbulator's purpose here but this might be an example of this particular modern airfoil NOT needing turbulators (per Schleicher at least). ;-)
>
> Remind me - how did we get from talking about waxing onto the subject of turbulators? ;-)

With modern glider aerofoils having such long laminar flow on the lower surface the blowholes on the various ASW-type ailerons/flaps *are* the turbulators on the wing aerofoil. Same as the JS aerofoil with blowhole turbulators at 95% chord which happens to lie on the flaperons.

[[email protected]]

On Thursday, August 30, 2018 at 1:02:35 PM UTC-4, John Foster wrote:
> On Thursday, August 30, 2018 at 8:37:17 AM UTC-6, Tango Whisky wrote:
> > Le jeudi 30 août 2018 15:59:36 UTC+2, OHM Ω http://aviation.derosaweb.net a écritÂ*:
> > > On Wednesday, August 29, 2018 at 7:20:29 AM UTC-5, Tango Whisky wrote:
> > > > Le mercredi 29 août 2018 13:42:25 UTC+2, Martin Gregorie a écritÂ*:
> > > >
> > > > > Read up on turbulators. They're not needed on modern airfoils,
> > > >
> > > > Except that ALL modern airfoils use turbulators.
> > >
> > > I am pretty certain that on my ASW-27B the only turbulators on the wings are small 2cm wide sections just in front of the underside NACA vents which pressurize the ailerons and flaps. I can only guess at the aerodynamics of the turbulator's purpose here but this might be an example of this particular modern airfoil NOT needing turbulators (per Schleicher at least). ;-)
> >
> > Turbulators are either zig-zag / dimple tapes (all non-Schleicher), or blow holes (Schleicher). Both do the same job.
>
> Which again comes back to the smoothness of the wing surface as it potentially relates to dimples in a golf ball. With a rough wing surface (from sanding?), would that have the same effect on the surface boundary layer potentially? Would there be a part of the airfoil that would benefit more from such a treatment? And thus, how important to polish the surfaces to a mirror finish?

There isn't a meaningful benefit beyond the smoothness of a 400 grit finish, other than easier cleaning and longevity. Waviness and correct shape are more important.
Some airfoils like a little roughness. My old PIK-20 was a bit better with 400 surface than polished. When it would drop off in climb, I'd scuff with 400 back about 4 inches and the climb got better. I haven't see any other airfoils that showed that characteristic.
FWIW
UH

[Steve Leonard[_2_]]

On Thursday, August 30, 2018 at 12:26:43 PM UTC-5, kirk.stant wrote:
>
> "It's more fun to win in a ratty looking glider than to lose in a perfect
> one"

Dan Sazhin, I think you need to put that on a tee shirt!

[Dave Nadler]

On Thursday, August 30, 2018 at 2:30:44 PM UTC-4, wrote:
> ...My old PIK-20 was a bit better with 400 surface than polished.
> When it would drop off in climb, I'd scuff with 400 back about 4 inches
> and the climb got better.

Hank! That's a hell of away to remove bugs!

> I haven't see any other airfoils that showed that characteristic.

Only because newer aircraft owners won't let you try it.

[Papa3[_2_]]

On Thursday, August 30, 2018 at 3:56:25 PM UTC-4, Steve Leonard wrote:
> On Thursday, August 30, 2018 at 12:26:43 PM UTC-5, kirk.stant wrote:
> >
> > "It's more fun to win in a ratty looking glider than to lose in a perfect
> > one"
>
> Dan Sazhin, I think you need to put that on a tee shirt!

Micro-turbulated LS3. Currently being "restored", so we'll have a before/after example.

[Steve Leonard[_2_]]

On Thursday, August 30, 2018 at 3:44:58 PM UTC-5, Papa3 wrote:
> On Thursday, August 30, 2018 at 3:56:25 PM UTC-4, Steve Leonard wrote:
> > On Thursday, August 30, 2018 at 12:26:43 PM UTC-5, kirk.stant wrote:
> > >
> > > "It's more fun to win in a ratty looking glider than to lose in a perfect
> > > one"
> >
> > Dan Sazhin, I think you need to put that on a tee shirt!
>
> Micro-turbulated LS3. Currently being "restored", so we'll have a before/after example.

From what I heard, I believe that would be more accurately described as a "Macro-turbulated LS3".

[Charlie M. (UH & 002 owner/pilot)]

I believe the SGS-1-35 (and others) had the same/similar airfoil. They did not seem to do well with a waxed surface, even worse when wet/bugged.
Sorta along the lines of the dimples on a golf ball, a little roughness reduced the huge drag at airflow separation. Better a little when/where you want it, than a huge trip somewhere else.

An old trick was to clean the wing, then sponge down with liquid soap to about the spar. Then, if it rained, the water sheeted instead of beaded. The L/D dropped, but not as bad.

Good example, years ago at Mifflin PA, from the SE returning home, a flight of about 6. A couple ASW-20's, I believe Ventus, an LS-6 and a 1-35.
8 miles out, we hit a little rain. The glass ships all got marginal on final glide, the 1-35 sank fast compared to us. We crossed the last ridge OK, the 1-35 had some trouble.

As to blow holes, they are more like a "variable turbulator strip", the amount they trip the airflow is roughly linear with the airspeed.

[Soartech]

Getting back to "what is hard wax?" M&H tells me it is also known as Jeweler's rouge, a stick of a very hard wax that contains a very fine abrasive such as iron oxide (reddish brown) and is used with a cloth wheel to polish metals (or gelcoat).
It is totally different from softer, protective waxes such as paste wax, Carnuba, etc. and is used as a polishing agent, not for protection.

[Jonathan St. Cloud]

What is recommended for polyurethane finishes?

[[email protected]]

Non silicone containing good quality (preferably UV filtering) car hand application polish is ideal for PU.

[[email protected]]

On Friday, August 31, 2018 at 11:38:56 PM UTC-4, Soartech wrote:
> Getting back to "what is hard wax?" M&H tells me it is also known as Jeweler's rouge, a stick of a very hard wax that contains a very fine abrasive such as iron oxide (reddish brown) and is used with a cloth wheel to polish metals (or gelcoat).
> It is totally different from softer, protective waxes such as paste wax, Carnuba, etc. and is used as a polishing agent, not for protection.

The rouge provides polishing action and the wax carrier is deposited on, and worked into the surface by the resulting heat of polishing. This seals the gelcoat.
After completing, I usually go over with Scotchgard Marine Liquid wax to do final clean up and provide added protection. I think M&H does the same thing.
UH

[[email protected]]

On Tuesday, August 28, 2018 at 8:30:22 AM UTC-4, FranCP wrote:
> Hi,
> Can hard wax be replaced by liquid wax application? Of course silicon free, as well as other harmfull adds.
> Although i've seen guys maintaining their gliders purely on applying liquid wax regularly, i guess it wont seal & protect the gelcoat as well as a good anual hard wax buffing.
> ¿Any advice?
> Thanks

Is there any evidence that waxing is beneficial - or is it just part of the lore?

[[email protected]]

On Sunday, September 2, 2018 at 7:15:52 AM UTC-4, wrote:
> On Tuesday, August 28, 2018 at 8:30:22 AM UTC-4, FranCP wrote:
> > Hi,
> > Can hard wax be replaced by liquid wax application? Of course silicon free, as well as other harmfull adds.
> > Although i've seen guys maintaining their gliders purely on applying liquid wax regularly, i guess it wont seal & protect the gelcoat as well as a good anual hard wax buffing.
> > ¿Any advice?
> > Thanks
>
> Is there any evidence that waxing is beneficial - or is it just part of the lore?

In my case almost 40 years of observing and evaluating the condition of polyester finishes that have and have not been kept well polished and waxed.
Polished and waxed is far superior.
UH

[[email protected]]

On Sunday, September 2, 2018 at 7:56:48 AM UTC-5, wrote:
> On Sunday, September 2, 2018 at 7:15:52 AM UTC-4, wrote:
> > On Tuesday, August 28, 2018 at 8:30:22 AM UTC-4, FranCP wrote:
> > > Hi,
> > > Can hard wax be replaced by liquid wax application? Of course silicon free, as well as other harmfull adds.
> > > Although i've seen guys maintaining their gliders purely on applying liquid wax regularly, i guess it wont seal & protect the gelcoat as well as a good anual hard wax buffing.
> > > ¿Any advice?
> > > Thanks
> >
> > Is there any evidence that waxing is beneficial - or is it just part of the lore?
>
> In my case almost 40 years of observing and evaluating the condition of polyester finishes that have and have not been kept well polished and waxed.
> Polished and waxed is far superior.
> UH

Inspecting fiberglass/gelcoat trailers that are kept outside will help answering that question. Unless you polish/wax those trailers at least twice a year they will quickly deteriorate in a bad way. Now look at that type of trailer kept indoors.