David Pedrick huh? (TAFG origin)

This broker needs to learn his job better:

http://www.yachtworld.com/boats/1989/Ericson34-200-By-Pacif...--2127340/Semiahmoo/WA/United-States

Tim,

I believe Dave Pedrick is credited with engineering the original concept of the tri-axial force grid.

Maybe so but it was not the first boat to use this design.

Right

The 30+ had the first grid stucture in the E boat family-although it was partial, rather than full length. Then the Ericson 38 was the first E-boat to use a full TAFG structure.

Later the 36 and 33 RH boats, and then all of the newer BK 32, 34, 35 and all of the variants of those models (built AFTER 1980) employed it as well.

And you know what-I DO recall something about Pedrick being invloved...Martin may have a better recall of this than me, but now that you mention it, it sounds familar.....

Cheers,
S

Tim..

I don't think he was talking about the boats designer but rather the designer of the Triaxial Grid which appears to be Dave Pedrick.


This is an exceprt from Blue Water Sailing from an article on teh Caliber 40 LRC:

"Similarly, Caliber’s "Integral Strength-Grid System"
probably accounts for high scores for "stringers & floors"
(average score of 9). With this grid system, keel, tanks,
lids, baffles, stringers and subsole are heavily glassed
together to form a powerful grid structure that is integral
to and the backbone of the hull and as the builder says,
"spreads primary sea loads over a large area." Early varia-tions of this idea were employed by both Ericson and
Hunter in the early ‘80s. First designed by David Pedrick,
and dubbed the "Triaxial Grid System" by Ericson, it really
works."

Seth, you mentioned....

Seth,

In the above post you mentioned that the E30+ was the first Ericson boat to use the TAFG, but that it was only a partial grid. Does the "partial" refer to all E30+ boats, including subsequent years, or did later years of the E30+ use the full grid? The sales brochure on this site talks of the TAFG as if it was a full implementation.

I'm wondering for my boat, which was 1984, hull #637.

And if you know, why was only a partial grid installed, rather than immediately going for a complete grid system?

Thanks for any information.
Frank

Right

Correct-I was referring to the TAFG concept-not the boat designs. My recollection is that this a a construction concept we attributed to Dave P., and employed it on all the post 30+ E Boats.

Frank,
The TAFG used on the 30+ (and all of the 30+ boats) was "partial" in that it was the first and most basic iteration. It did not extend the full length of boat as with later designs. It was implemented when the interior tooling for the 30+ was done. The 30+ hull used the hull tooling from the 30-II, but with an inboard rudder rather than the transom hung outboard rudder on the 30-II (and a few other mods), IIRC. The 30+ had an entirely new interior tooling from the 30-II, and hence structure. This was the time Ericson was getting away from the old conventional wooden bulkhead and stringer type interior setup. The 2 key reasons were first to develop tooling which would reduce construction costs, and second to improve strucutral integrity with the least weight (since lbs = $).

So, it was simply the first E boat with the concept. It worked well, and all new designs (which were clean sheet designs rather than a carry over) employed it fully, including the RH boats.

Hope that helps. This is what I recall, anyway-since this was during my time there.

Thanks, Seth...

Thanks, Seth, for your quick and helpful reply. It's great to hear all these details about our boats!

Frank

Seth said:

This was the time Ericson was getting away from the old conventional wooden bulkhead and stringer type interior setup. The 2 key reasons were first to develop tooling which would reduce construction costs, and second to improve strucutral integrity with the least weight (since lbs = $).

Click to expand...

I had always wondered about the TAFG design versus the bulkhead/stringer setup like the Independence 31 is built. Always figured it was a weight and strength issue. It's interesting seeing the progression in hull designs and intended uses of the boats.

Seth (or others), am I correct that the traditional construction is more in keeping/better suited with the design concepts of the Independence 31 as a classic coastal cruiser versus the later boats which had a "sportier" orientation? Sorta thinking that the inherently heavier construction of the Independence 31 becomes a plus versus the same size shape boat built with a TAFG and hence with less displacement for her purpose as a coastal cruiser. Hope that makes sense

The Skeleton chronicles

Perhaps it's worth noting that the transition from a FRP interior molding (which saved a ton of production time/money that might have been spent on carpentering up wood settees, hull ceilings, and headliners to...
a Load-Carrying internal drop-in "frame" was perhaps kind of gradual in the boat building industry.

I personally saw it progress from the lower/settee interior molding of my Ray Richards-designed Ranger 20 (and the R-24 I crewed on) to a more-complete liner/interior in my Hinterhoeller-designed Niagara 26. The later design still had full or partial ply bulkhead pieces heavily glassed to the hull that carried the shroud load via a large size chain plates.

Our 80's Olson 34 actually has a multi-part FRP set of interior moldings that carry the shroud loads after ss rods convey those loads down from the deck "pass through" fittings. This is like the Ericsons of the same era. My interior mold is not a one-piece TAFG, however.

Looking at a King-designed E-boat of the 80's I see the interior TAFG go all the way from bow to stern. This is different than ours, in my mind, because the TAFG has to have its layup varied for each part of the load and geographic position in the boat, and seems to cover the whole inner hull.
I guess that my boat might be called a "partial TAFG" in comparison. In most of my boat, working around the tabbing, I can access the inside hull directly. Owners of TAFG Ericsons are sometimes jealous.

An aside: I spent some difficult hours helping a friend do some plumbing work in the area under his cockpit of a mid-80's Hunter 31. Very similar drop-in interior total-grid system... except that the QC in finishing up where all the hoses and wires go was terrible.
We spent considerable time tidying up sharp edges and straightening out routing of stuff. It was quite an obvious step down in fit and finish compared to the Ericsons I have looked into.

So, to me, the evolution from "furniture" to "load carrying" was where the TAFG really broke from prior production building convention.

Another .02 wasted!


Loren