posted 10-13-2005 10:02 AM ET (US)            

Cases in point:
Forward shelter bow attachments. These are screwed directly into the glass on the inwales, with no wood backing. There are few, if any reports of fiberglass spiderwebbing or cracking, and yet these shelters are under a great deal of pressure from wind and wave action. When I had a shelter installed on my 15, the canvas maker called a local boatyard to ask about techniques to beef up the backing behind this point in the design. The boatyard's reply? "What kind of boat is it?" "A Whaler? Oh, hell, just install it - they're glass is heavy duty." My guy was suprised enough to mention it to me when I took delivery. On most boats, he would have put a wood mounting pad there to disperse some of the stress.

posted 10-13-2005 10:44 AM ET (US)            

Gelcoat thickness, i.e, does not provide the real strength. It's how the fibers of the fiberglass cross each other and in which direction, together with the backing of the fiberglass, that provides true strength.

http://www.whaler.com/Rec/default.asp?content=construction

Whaler may not have the thickest layer of gelcoat or the thickest layers of fiberglass but the Unibond construction method makes for one of the strongest fiberglass hulls available.

Erik

posted 10-13-2005 12:31 PM ET (US)            

That said, to Buckda's point, I also have small u-mounts (held on by two screws each) that my Bimini straps attach to and they show no sign of wear on my 98 Montauk.

posted 10-13-2005 02:29 PM ET (US)            

quote:

---

I don`t think any builders of small pleasure boats are using hand lay up anymore.

---

posted 10-13-2005 03:26 PM ET (US)            

The glass is NOT from a chop-gun. Anyone who has ever laid up various kinds of fiberglass will know the difference (and I have). The glass on whalers is called "matt". It comes in cloth sheets and is made up of 1-2" unidirectional strands of glass. This gives it the maximum amount of strength given the way in which it is utilized. While draditional "boat cloth" (woven strands that run the length and width of the sheet) is better in traditional contruction methods as it provides directional tensile strength in four linear directions. The unibond construction method relies on the stress being distributed in all directions AROUND the foam core. This means it must have tensile strength around a full 360 radius. Thus, matt cloth is the better option.

posted 10-14-2005 10:48 AM ET (US)            

Whoa. Peter, next time you might consider engaging your brain before putting your fingertips in motion.

The fiberglass skins of Whaler hulls are laid up with predominantly chopper gun applied resin and 'glass fiber. While 'glass mat is used in areas of high stress and abrasion, like the keel an certain stressed inside and outside corners, the rest of the skins are just chopper gunned.

The skins are not that thick either. 1/8 inch is typical of the smaller Whalers. As the hulls get larger so must the thickness of the skins and the lay-up schedule is increased accordingly.

But Peter is correct that the strength of the Whaler hull comes from the composition of the Unibond process. It is not the skins alone that provide the strength but the combination of the foam and the two skins.

Whaler hulls are remarkably strong for their weight. Conventional hulls must derive their strength from the fiberglass skin itself and thus the fiberglass is much thicker.

Whaler hulls are susceptible to punctures because of their thin skins but as (apparently the only) one here who has actually swung a sledge hammer against the side of a Whaler hull, I can tell you it is surprisingly strong.

I can also tell you the thickness at the keel of even a little 13 footer is as much as 1/2 to 3/4 inch.

It is also something of a myth that the first fiberglass boats were "overbuilt" and thus super strong. It is true that early manufacturers didn't quite understand all the strength properties of fiberglass and may have added more here and less there in their hulls, but mostly they didn't get the ratios of 'glass to resin perfect and simply added weight that didn't add strength.

posted 10-18-2005 02:28 AM ET (US)            

Don't shoot! I have to take back something I said above. The maximum skin thickness of a 1970 13 footer appears to be 1/4" at the keel, not 1/2" as I stated. The skin thickness tapers down to 1/8" at a distance from the keel of only about 6 inches.

I just happen to have a cross section chunk from a 1970 Sport 13 here which is some of what I have left over from a hull I completely cut up and dissected some years ago, the famous "Chainsaw Whaler."

RocketMan,

posted 10-18-2005 02:36 PM ET (US)            

By the way, it's actually quite easy to tell chopper gun lay-up from hand-laid matt. Matt comes as a flat sheet of glass and as such the glass strands are generally all straight and don't appear disturbed. When glass is laid up with the chopper gun it does not lay flat on the mold. It has to be flattened using a roller (so does matt, but not as much) and durring this process, the strands of glass are forced down and often become bent or curved. Thus, if you look at the fiberglass up close, look for strands that are bent over, or appear to be folded. If there is very much of this, it was likely applied with a chopper gun.

Come to think of it, in the areas of high wear (along the keel, and sponsons), I distinctly remember seeing a boat cloth pattern in the glass. This obviously was laid up by hand.

posted 10-18-2005 09:53 PM ET (US)            

www.fiberglasswarehouse.com/chopped_strand_mat.asp

And there is fiberglass cloth:

www.fiberglasswarehouse.com/fiberglass_cloth.asp

Both are used in traditional hand laid, or rolled fiberglass boat construction. Often a combination of the two will be used for layup, depending on the application.

I think the chop gun was designed to emulate the strand mat cloth. A quick way to build up the fiberglass strands with resin to achieve a desired hull thickness in non-structural applications.

It is easy to confuse a boat that was hand laid with mat cloth with a boat that was built up with a chop gun.

Rich

posted 10-19-2005 12:06 AM ET (US)            

That is an interesting photo. I suspect the outer hull skin is down, the inner hull skin up with backing material showing.

posted 10-19-2005 12:11 AM ET (US)            

You can understand their position. They have done research and testing to find what works well and at the same time does not cost too much. There is no problem in making a boat fantastically strong and light, but just that it can be very expensive. If you are in a high-volume production situation, you want a laminate that is strong, easy to build, and not too expensive.

You should look at the laminate with an eye to the results, not the construction. Whatever thickness it is, the hulls will last for decades if given reasonable care and not abused. That is a better yardstick that measuring the thickness of a laminate and pronouncing an opinion on it.

posted 10-19-2005 07:36 PM ET (US)            

Check these threads out:

http://continuouswave.com/ubb/Forum1/HTML/004754.html

posted 10-21-2005 12:25 AM ET (US)            

http://photobucket.com/albums/v408/andygere/Whaler%20details/?action=view¤t=Outerhullskin.jpg

posted 10-21-2005 12:10 PM ET (US)            

"its a chopper gun POS"

"will vary from almost nothing to I would say no more than 1/4 inch and im being generous "

"cut your hull on a sharp object and your overpriced new Boston whaler"

You come on an enthusiasts website, and insult their boat b with word of "POS" and "overprice" and you want everyone to treat you nice?

By most peoples defintions of Internet Etiquette, most would call you a troll.

Quote from http://en.wikipedia.org/wiki/Internet_troll

posted 05-08-2006 01:06 AM ET (US)            

I always worried about penetrating the green fiberglass layer.Whenever I saw a chip past the gelcoat it was covered up immediately with marinetek.
Like any unibody type construction. Its very strong when all is sealed. You have to be vigilant in keeping whalers watertight. The weak spot was always the damage done by the trailer. It really doesn't take much for a sharp object to cut into the fiberglass and into the foam area. As long as you have your trailer set up correctly so that it is supported on the keel and you don't run into rocks and pilings the hulls can take the pounding from water without any problems.

posted 05-08-2006 01:28 AM ET (US)            

Yes, they sink.

That aside, they are famous for their premium gelcoat and glass work. I went through their factory 6 years ago while in the area on business and their tour is very detailed and explaines alot in skill of hull layup.

They start with the gelcoat in the mold and then follow it up with a layer of choppergun. Their explaination of the first layer of choppergun first next to gelcoat is that it provides inital strength and hides the print through affect of glass mat or woven glass matt which they apply next. 4 layers of handlaid glass or woven matt with chopper gun shot in between each handlaid matt make up the hull and more in key areas.

It was very informative. They do great work and make no excuses for choppergun glasswork in part of the makeup of their hulls.

Whaler does use chopper gun glass in their hulls. Both the classics and new models have it. My question is how much handlaid matt is in there as well in the different models.

I would guess that the classics have more chopper gun glass and the newer models have both. I am guessing on this because of the big difference in hulls weights between old and new. That weight is probably more glass work.