Waxing "under" Bunks

[jon4pres]

97sport I have read several things that contradict your statement. I heard that in racing boats they dont even wax the hulls of the boats. If you think about it. Drop water on a waxed surface it beads up into puddles. Drop water on an unwaxed surface it quickly disepates (sp) and runs away.

[CHassmann]

It sure is a lot easier to keep clean when it is waxed. I would think that a waxed hull would mean less friction, better gallons per hour at any speed.

[jhiestand]

There was a huge thread on waxing hulls in Malibu Boat Owners, and it essentially came down to non-waxed hulls are supposedly faster due to minute irregularities along the running surface that cause tiny air pockets, which in turn cause the boat to have less drag on the surface. Wax fills in those pockets creating a more uniform surface and thus, increasing friction while underway.

That being said, it was also pretty much agreed on that it's still better to wax the bottom for maintenance purposes, regardless of negligible performance differences.

I can't explain better performance with a waxed hull, but if it both increases performance AND makes it easier to maintain, then that's a no-brainer!

[Mikeski]

I just spoke with a co-worker, whom I would consider an authority on the subject. He is a fluid dynamics engineer that has done work for Arneson, raced hydroplanes, airplanes, and a general tweak that is waay smarter than me on these topics. He said that it doesn't matter from a performance standpoint. It is important to have a smooth surfact but not necessarily a waxed surface. For the first inch or so where the water is breaking along the hull it flows in laminar fashion and it could possibly make a tiny unmeasurable difference. He also said this was always a good debate topic.

The biggest advantage of waxing the hull is that the wax tends to fill the small voids in the gelcoat so it could help to reduce the chance of getting bubbles in the gelcoat.

The drag boat experience is more of a handling issue, and after talking to my knowledgable co-worker that was probably based more on legend than fact. There was a theory that the boat was more likely to pop out of the water and flip if it was waxed? I guess these things are more significant whan your life is on the line. Also, the drag boats are painted not gelcoat so that makes a difference too.

I guess if I get really bored and I am looking for some very uncomfortable punishing laborious work I may crawl under my boat and wax it... Although, I probably will wax down under the bow so it's easier to get the towing bugs off.

[slob02]

I too have heard what MIKESKI says about waxing the bottom. I have heard the beading of the water causes it to slow down??? Never tested it though.

[CHassmann]

The biggest advantage of waxing the hull is that the wax tends to fill the small voids in the gelcoat so it could help to reduce the chance of getting bubbles in the gelcoat.

I guess if I get really bored and I am looking for some very uncomfortable punishing laborious work I may crawl under my boat and wax it... Although, I probably will wax down under the bow so it's easier to get the towing bugs off.

Good point Mikeski. It's really not that hard to wax the hull though. I'll apply the wax on a section and then wipe off the previous section, moving from the bow to stern. I make sure to roll a towel up and put it under my head so I don't get a stiff neck. I just can't figure out why I can't get anyone to help me do it.....lol........

I can imagine that moving around the "trailer obstacles" may be a little more difficult for those that have stomach muscles that are stretching...ie: a big gut........ha,ha....

[Grant_West]

So do you think there is any truth to 97 Sports clame to 3 MPH gain after waxing the hull

[ag4ever]

Hard to say, but I doubt it. I will bet there are so many variable when you are running, it could have been a tail wind giving him the extra MPH.

At the fluid speeds we are talking about, there would be very little difference trying to get liminar flow or turbulant flow around the boundry layer. For non-planing hulls, there might be some truth in the wax-nowax debate, but not in planing hulls.

[noti_dad]

Mikeski, ask your friend about graphite on the bottom and it's influence. I had a Biesmeyer flaybottom for ski racing. We used a graphite "wax" on the bottom of it and my speed ski. The 'old racing guys' we learned from told us to use, so we did. Was supposed to make it go faster with less resistance. Never really tested to see if there was a differance. If someone wants performance they could coat the water surface with that stuff. :shock:

[Mikeski]

Notidad,

He said that the difference between a waxed and polished surface will be unmeasurable for our purposes. Do not let the bottom of you boat get fuzzy with seaweed or barnacles. Even boats painted with flat finish bottom paints should not show any signs of reduced performance.

He also noted that some of the racing sailboat guys wax thier hulls but the smallest difference in a slow moving displacement hull could mean the difference in a few extra inches traveled over an hours time. In sailboat races those extra inches might be the difference between winning and losing the race. Keep in mind it's a completely different set of variables.

I guess the bottom line is do what makes you happy.

To Grant's question about the 3mph claim, it's likely that some other variable caused this difference (say something like cleaning out the speedo tube), my buddy didn't think the claim was valid.

[rocco]

Waxing under your boat

I have been reading all the posts about waxing the bottom of your boat.
I wax my boat once a month (everywhere)..You can tell after about 3 weeks after you wax it,,,#1.it don't come off the trailer as fast.
#2,it don't go on the trailer as easy...#3..you lose a couple of mph.
I have a 2000 Ski Nautique,..It could be a Mind thing too...But the wife, always tells me when she as trouble getting onto the trailer..the boat needs waxing again........enough said???????

[97sport]

Yes I gain 3 m.p.h. afterwards. Maybe I was misunderstood about this. I dock my boat and pull it out about every 5-6 weeks to clean it. I figure mind as well wax it while it's on the trailer. When bringing it back to my dock from the boat ramp at 30mph engine runs 2900-3000 rpm. before I pull it for cleaning at 30mph it takes 3200-3300 rpms. Don't know if it's the wax or just cleaning the marine growth off?