How to derive the Hull # from the HID?

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Jack in Norfolk
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Joined: Dec 6th, '14, 16:24
Location: J/24 USA 262 "Doreen". Able 20 (project). CD10 hull # 2224. Marblehead, MA

How to derive the Hull # from the HID?

Post by Jack in Norfolk »

When I got my Cape Dory 10, the builder's plaque was missing. There is an oval shaped dark spot, and two nail holes on the teak transom insert back aft where the plaque should be. The HID is mostly decipherable on the outside of the transom. Is it possible to know which CD10 I have based on the HID?
Thank you.
"Teach your child the love of sailing and they will never have money for drugs."
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Sea Hunt Video
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Re: How to derive the Hull # from the HID?

Post by Sea Hunt Video »

Jack:

Several years ago Good Old Boat ("GOB") published an article on hull identification numbers (HINs).

As GOB explains it, the characters (numbers or letters) in the "model-year format" which existed prior to 01 January 1984 are decoded as follows:

Character positions 1, 2 & 3 of the HIN are the manufacturer's identification code and assigned by the US Government;

Character positions 4, 5, 6, 7 & 8 of the HIN are an alpha-numeric serial number established by the manufacturer;

Character position 9 of the HIN could be the letter "M" if the sailboat was built before 01 January 1984. The letter "M" signifies the manufacturer is using the "model-year format" not the "numerical straight-year format";

Character positions 10 & 11 are the year of manufacture; and

Character position 12 is a letter indicating the month of manufacture in the "model-year format". Interestingly, this lettering starts with the letter "A" signifying August; "B" is September; "C" is October, etc.

Before 01 January 1984, if a manufacturer wanted to, he (or she) could alternatively use the "numerical straight year format" instead of the "model-year format". Then characters are decoded as follows:

1-8 are the same as above for the "model-year format";

9, 10, 11 & 12 would be the month and year of manufacture. Instead of an "M" at character 9 signifying "model-year format" there would be a number as part of the month (2 digits), followed by year (2 digits).

Post 01 January 1984 you could use another third format which is called the "new format" (catchy phrase). In the "new format", the characters are decoded as follows:

1-8 are the same as above for the "model-year format";

9 is the month of manufacture - "A" is January, "B" is February, etc.

10 is a number digit signifying the last digit of the year of manufacture or certification

11 and 12 are the model year.

I hope this helps a little. :)
Fair winds,

Roberto

a/k/a Sea Hunt "The Tadpole Sailor"
CDSOA #1097
________________________________
"I wish to have no Connection with any Ship that does not Sail fast for I intend to go in harm's way." Captain John Paul Jones, 16 November 1778, as quoted in Naval History and Heritage Command, http://www.history.navy.mil
Jack in Norfolk
Posts: 35
Joined: Dec 6th, '14, 16:24
Location: J/24 USA 262 "Doreen". Able 20 (project). CD10 hull # 2224. Marblehead, MA

Re: How to derive the Hull # from the HID?

Post by Jack in Norfolk »

Very helpful. Thanks!

I checked this against a Typhoon in a boatyard down the street. The HID and the number on the builder's plate correlate to the formula that you shared.

So it would seem that I have CD10 number 2224.
"Teach your child the love of sailing and they will never have money for drugs."
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Re: How to derive the Hull # from the HID?

Post by Sea Hunt Video »

Jack:

According to another section of this board (Cape Dory History), there were 2260 CD 10s mfg. between 1964-1983. Your hull number 2224 would be one of the very last CD 10s built by Cape Dory Yachts circa 1982/1983.
Fair winds,

Roberto

a/k/a Sea Hunt "The Tadpole Sailor"
CDSOA #1097
________________________________
"I wish to have no Connection with any Ship that does not Sail fast for I intend to go in harm's way." Captain John Paul Jones, 16 November 1778, as quoted in Naval History and Heritage Command, http://www.history.navy.mil
Jack in Norfolk
Posts: 35
Joined: Dec 6th, '14, 16:24
Location: J/24 USA 262 "Doreen". Able 20 (project). CD10 hull # 2224. Marblehead, MA

Re: How to derive the Hull # from the HID?

Post by Jack in Norfolk »

Sea Hunt Video wrote:Jack:

According to another section of this board (Cape Dory History), there were 2260 CD 10s mfg. between 1964-1983. Your hull number 2224 would be one of the very last CD 10s built by Cape Dory Yachts circa 1982/1983.
It's funny, there is a Typhoon here in town named "The Last Typhoon." I believe that she was the last one built. I guess Marblehead attracts "end of the line" CDs (though I found mine on a lake in Maine).

When my friend attempted to decode my HID which is CPDA2224M79K, he told me that she was hull # 79. From decoding my J/24 and my Laser, I was pretty sure that 79 was the year, but he is very knowledgable about all things Cape Dory and was friends with Mr. Vavolotis.

All of the wood on mine is teak, except for the rudder. The interior was buff. The more I poked around on the net, the less I believed that she was only number 79. The fact that mine is not a double hull really seemed to debunk his claim.

I'll put up pictures in the project forum soon. Thanks again for the helpful input.
"Teach your child the love of sailing and they will never have money for drugs."
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Re: How to derive the Hull # from the HID?

Post by Sea Hunt Video »

Jack:

I am not that familiar with CD 10s. However, if your hull number is CPDA2224M79K, that seems odd because the "79K" indicates your CD 10 was mfg. in June 1979. The "M" in front of the "79K" indicates Cape Dory Yachts was using the model year format.

If there were only 2260 total of the Cape Dory 10s mfg. between 1964 and 1983, it seems unlikely that between June 1979 (when hull #2224 was mfg. according to the HIN you provided) and 1983 (a period of approximately 3 1/2 to 4 years) that Cape Dory Yachts only built 36 of the Cape Dory 10s. Although I guess this is possible. It would mean CD Yachts built an average of 145-150 per year for the first 15 years and then built only an average of 10-12 per year for the next 3-4 years perhaps concentrating their mfg. efforts on larger sailboats.

If you have a certificate of title, or similar registration document, is the hull number on the document consistent with the hull number stamped on your CD 10 :?:

Your initial post suggested the hull number was "mostly decipherable". Is it possible one or more of numbers are something other than 2224 :?:

An possible interesting mystery. :wink: Where is Andrew Vavolotis when we need him :!: :wink:
Fair winds,

Roberto

a/k/a Sea Hunt "The Tadpole Sailor"
CDSOA #1097
________________________________
"I wish to have no Connection with any Ship that does not Sail fast for I intend to go in harm's way." Captain John Paul Jones, 16 November 1778, as quoted in Naval History and Heritage Command, http://www.history.navy.mil
Jack in Norfolk
Posts: 35
Joined: Dec 6th, '14, 16:24
Location: J/24 USA 262 "Doreen". Able 20 (project). CD10 hull # 2224. Marblehead, MA

Re: How to derive the Hull # from the HID?

Post by Jack in Norfolk »

I went down a similar thought path. I was thinking that maybe they were not turning out as many dinghies at the end?

The HID character in question is the last one. The top of the last digit is worn. It could be 'K' or 'R', but 'R' was not listed as a possible character under the format.

Sadly, I don't have any paperwork. My buddy owns a wooden boat shop. He has very little interest in glass boats. He just wanted it out of his place.

It would be interesting to have someone with a late model CD10 post their HID and plate number.

ImageCD10 HID by 262_driver, on Flickr
"Teach your child the love of sailing and they will never have money for drugs."
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Sea Hunt Video
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Location: Former caretaker S/V Bali Ha'i 1982 CD 25D; Hull 69 and S/V Tadpole Typhoon Week

Re: How to derive the Hull # from the HID?

Post by Sea Hunt Video »

Jack:

That hull number embedded on the stern is pretty definitive evidence that you have CD 10 Hull # 2224 mfg. in 1979 (probably June). Assuming the total number of CD 10s is accurate (or close) then you have one of the last CD 10s built and it was in 1979.

As mentioned, given the above facts, it is probable that after 1979 Cape Dory Yachts focused their yard and staff on building larger and larger sailboats from CD Typhoons (18 1/2 ft.) all the way up to a CD 40 :!: I am guessing there was a larger profit margin in the larger sailboats.

Your buddy just wanted a CD 10 "out of his place" :?: Man, you are one lucky guy :!: :D :wink:
Fair winds,

Roberto

a/k/a Sea Hunt "The Tadpole Sailor"
CDSOA #1097
________________________________
"I wish to have no Connection with any Ship that does not Sail fast for I intend to go in harm's way." Captain John Paul Jones, 16 November 1778, as quoted in Naval History and Heritage Command, http://www.history.navy.mil
Jack in Norfolk
Posts: 35
Joined: Dec 6th, '14, 16:24
Location: J/24 USA 262 "Doreen". Able 20 (project). CD10 hull # 2224. Marblehead, MA

Re: How to derive the Hull # from the HID?

Post by Jack in Norfolk »

Sea Hunt Video wrote:Jack:

That hull number embedded on the stern is pretty definitive evidence that you have CD 10 Hull # 2224 mfg. in 1979 (probably June). Assuming the total number of CD 10s is accurate (or close) then you have one of the last CD 10s built and it was in 1979.

As mentioned, given the above facts, it is probable that after 1979 Cape Dory Yachts focused their yard and staff on building larger and larger sailboats from CD Typhoons (18 1/2 ft.) all the way up to a CD 40 :!: I am guessing there was a larger profit margin in the larger sailboats.

Your buddy just wanted a CD 10 "out of his place" :?: Man, you are one lucky guy :!: :D :wink:
It was a "get it out of here," price. :) She was a total basket case. I am making slow progress.
"Teach your child the love of sailing and they will never have money for drugs."
Jack in Norfolk
Posts: 35
Joined: Dec 6th, '14, 16:24
Location: J/24 USA 262 "Doreen". Able 20 (project). CD10 hull # 2224. Marblehead, MA

Re: How to derive the Hull # from the HID?

Post by Jack in Norfolk »

In 1979, were the boats being built in East Taunton, MA?

Thanks
"Teach your child the love of sailing and they will never have money for drugs."
User avatar
Sea Hunt Video
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Location: Former caretaker S/V Bali Ha'i 1982 CD 25D; Hull 69 and S/V Tadpole Typhoon Week

Re: How to derive the Hull # from the HID?

Post by Sea Hunt Video »

Jack:

One of the 1978 Cape Dory brochures lists the address for Cape Dory Yachts as 160 Middleboro Avenue, East Taunton, Ma. 02718. I think Cape Dory Yachts started out in Bridgewater, Ma. circa 1963.

From the above I would "assume" Cape Dory Yachts was fully transitioned to East Taunton, Ma. by 1979.

Good luck :!:
Fair winds,

Roberto

a/k/a Sea Hunt "The Tadpole Sailor"
CDSOA #1097
________________________________
"I wish to have no Connection with any Ship that does not Sail fast for I intend to go in harm's way." Captain John Paul Jones, 16 November 1778, as quoted in Naval History and Heritage Command, http://www.history.navy.mil
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