Kadey Krogen 42 hull thickness...

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Apr 3, 2011
Vessel Name
Phoenix Hunter
Vessel Make
Kadey Krogen 42 (1985)
My apology if this has been discussed before, but I am interested in learning more about the KK 42 hull thickness. I have searched the topic on this forum but the search engine provides too many hits to sort through. Similarly, a google search provides too much to sift through

I have been looking at several KK 42s, 1985-1988 and am wondering about the thicknesses of the outer fiberglass hull, the foam core and the inner fiberglass hull section. Does anyone know these parameters?

Also, when sounding the hull with a hammer, the hull has different sounds, possibly representing the presence of voids in some sections. Can anyone provide me some insight into this?

It's a well constructed hull as long as it meets spec....so realy what does it matter what they are?

If it doesn't meet spec...it's now a poorly constructed hull...the nature of composite cores.

If there is widespread delamination...it doesn't mean the boat is going to sink right away...just how much hull repair you are willing to fix....or not and just "cocktail cruise her".
...I'd say that about KK the thickness issue is irrelevant.

My 2 cents
It (hull thickness) might be irrelevant but it is mu question, none-the-less. Tom Button felt it was 0.75", but wasn't sure from the drawings. Again, how are hammer soundings interpreted?

I have a 1986 KK 42 hull#100. I have a piece of the hull that I believe was a through hull cutout. To the best of my memory, it is between 3/4 & 1" thick. If you like, I will measure it for you as my boat is behind the house.
Last year I put an offer in on a 1982 KK42, the guy accepted my low ball offer of $65K, in doing my research I learned some of the hulls in the early 80’s were missing some of the stringers from the original design, some of the hull’s were later repaired under warranty by KK, when I contacted the KK office in Florida with the specific hull # I made an offer on they could not tell me if it was one of the hulls they repaired under warranty. I ended up walking away from the deal because the hull was so delaminated and it had several spots that were leaching, it just wasn’t worth it… there were two points were the surveyor’s screwdriver point went in the hull about a half inch… as for the hammer…. The surveyor walked up with a small mallet and tapped all over the hull and decks and within 5 minutes told me to not walk away but run away from this deal. It was hard because I really love the KK42… it was my first lesson in not letting emotions pick a boat.
LLoyds has the specks for GRP boats.

Very simple to understand , however the rules are for an all chop boat (or mat) and hull thickness can be reduced with a better (more roving) layup.

Most boat assemblers are very coy about laminate skeds , you may have to pull thru hulls.

These boats have been around a while so IF the hulls were sub standard the bigger problems would be known by now.

Tapping is not as effective as a tuning fork for finding hull bad spots.
Jim: The year KK42's you're looking at, have PVC cored hulls below the water line. I can't find the plug we took out when we added a new transducer but the total thickness of the 2 layers of glass and the core was over 1". Ask your surveyor what his experience is with cored hulls. When they sound the hull, it has a different sound than solid fiber glass. If you add a new transducer, some of the standard transducers are not long enough with the additional core material.

On a side note, KK changed from installing the FL120 to the SP135 around 1985.

Good luck.
Hulll X Section

Here you go. From 1986 Krogen 42, Hull #99. The top of the picture is the exterior hull.


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Thanks very much everyone.. I thought someone would have the answer! My surveyor thought that the outer layer was less than 0.75 and that seems to be the case from the photo. Also, he told me last night that the hull he "sounded" over the weekend was fine, so no need to worry there. He mentioned that the different sounds as he was tapping were due to the presence/absence of stringers etc as he worked up and down the hull.

Is it possible to get the build specs from KK. I have a 1972 Krogen designed trawler and had Jimmy Krogen at Traditional Yachts Send my everything he had on it. Cost was $500. I was very surprised at what I got. Every blueprint, lines drawings, Complete lamination schedule and specifics on types of cloth(by manufacturer) to be used, Specs on every item and mounting, All mechanicall drawings, etc. He also included an article written by MotorBoating magazine about my very boat, and lots of other interesting nostalgia. He even had the immersion tables. He told me there was one drawing he could not find. This boat was designed by his father and was the fore runner to the 42. It was befor Art Kadey came on. I have installed thru hulls and can tell you that close to the keel the hull is well over 3 inches thick. It was a fully cored hull. The specs called for a 3/4 inch balsa core, go figure. Oddly, James K. spec't 5 inch foam stringers thru out and foam ring frames. All of which have about 1/2 inch of glass over them. Engine beds have 4 inch solid teak laminated into the stringers in the engine bay. This boat was ordered with a pair of DD 4-53s. I would guess that Jimmy could dig up all kinds of things on a "newer" boat, like a KK42.
I've got all the specs and drawings from Krogen for the 42. If anyone wants them, send me your e-mail address.

EDIT: This offer is no longer available.
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If I could get a copy of the KK42 specs, I would appreciate it. Harpperjohn07@gmail.com

When this post went up, I was thinking about the photos you posted a few years back on your bow thruster project. So I thought you would have "the" photo.

John Harper, Golden Dawn, KK42-83
I've got all the specs and drawings from Krogen for the 42. If anyone wants them, send me your e-mail address.

Has anyone got these plans? I've not had any response to my PM.


Sent from my iPad using Trawler Forum
Did you get the plans you were looking for? I have some on disc from KK, I can email them if still needed.
Did you get the plans you were looking for? I have some on disc from KK, I can email them if still needed.

Hi Rekindle.
Unfortunately nothing has been received. Thank you for your kind offer. I will PM you my email address.

Thanks again

Sent from my iPad using Trawler Forum
KK42 Plans

Hi Rekindle,

I too am interested in the KK42. I tried to PM you but being a new member cannot send links by PM. Would you be kind enough to also email the KK42 plans to me, will@wavecable.com?

KK Plans

I'd love a copy also, Trying to decide to add the KK 42 to my list. I am looking at a 79 KK42 and I'm concerned about the cored hull.

specs and drawings from Krogen on KK 42


I could use a copy of those plans as well for the KK 42.

You had said -- "I've got all the specs and drawings from Krogen for the 42. If anyone wants them, send me your e-mail address."

So here is my e-mail address: alfamike8277 at yahoo dot com

Appreciate the help.


Keith passed away a few years ago. I know you can get the plans off the Krogen Cruisers website.
hull thickness at bow 1 & 1/8 inches

That is a shame - a loss to us all.

So sorry to hear that. Thanks for letting me know.

In answer to the fellow who was asking about hull thickness -- when bow thruster installed on 1980's vintage KK 42, the hull below the water line was drilled out for 10 inch cross thruster tube to be installed.

The removed piece personally inspected & measured was 1 & 1/8 inches thick. If you want pictures I can send them to you. Just send me your e-mail.

All KK 42's are not the same so your measurements will vary. Because it is a cored hull the thickness is not as critical a measurement to determine strength as you might think. ---- 3/4 of an inch or 1 inch or 1 & 1/8 inch is about the same strength if you end up on the rocks.

Other parts of the hull have various thicknesses that are different & vary as per KK specifications & depending which year & what yard built it, etc. .

As they say if you've seen one KK 42 - then you've seen one KK 42 -- not all the same, as sometimes made by different yards.


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Here is a view


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explain pic ?

Terry - what are we looking at there in your picture ?

Did you crash your boat into something & this is the impact damage ?

I can see it is some torn fiberglass of a Hull, but pic could use some more explanation ?

Looks like it was a serious strong hit ?


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Hope it wasn't one of those miserable shipping containers.
Anybody have KK 42 Plans?

I saw one poor soul passed away but are there others here that have plans/drawings for the KK42... around 1986?
Would love to have whatever you have on the KK42. Rnummi at Mac dot com
I have them all, but on paper on the boat. If any of you cross my path near a print center.....
I have them all, but on paper on the boat. If any of you cross my path near a print center.....

Umm, is there even a print center in the San Blas Islands? Not that NJ is even in the vicinity...:)
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