Hahn method frame building ?

[Tony P]

I’d like to know if when using the Hahn method to build and cut frames if we can stop there and assemble the hull in the upright fashion ? ?
I don’t see why not. Just make the frames actual size eliminating his extended ends. The only issue I see is the actual joints will not be in the proper scale positions on each frame. Opinions please. ???

 

[Dave Stevens (Lumberyard)]

I’d like to know if when using the Hahn method to build and cut frames if we can stop there and assemble the hull in the upright fashion ? ?
I don’t see why not. Just make the frames actual size eliminating his extended ends. The only issue I see is the actual joints will not be in the proper scale positions on each frame. Opinions please. ???

you are correct eliminate the extended ends no need for them because you can build the hull up right
are the frames pieces joined with chocks or do the ends butt to one another?

Hahn used only a few different blank patterns for most of the frames. For all the frame shapes to fit a common blank pattern he used 1 inch wide stock. If you make blank patterns to fit only 5 or so frames you can reduce the width to 3/4 wide maybe 1/2 wide. By not extending the frames and use more blank patterns of narrower framing stock will considerably cut down on wasted wood.

 

[Dave Stevens (Lumberyard)]

when you cut the parts by hand you have to space them out to give yourself enough room for cutting plus leave enough extra for final shaping



by cutting frames this way or building a frame blank the difference in the amout of wood is not much to be concerned about

but if you are cutting out frame parts and laser cutting them the parts are dead on and you can place them very close together less than a 1/32 between parts. Now you can save a sheet or two and when doing a production run it is worth it.



i did the Matthew with laser cut frame parts each part cut within a few thousandths and it still was difficult to assemble frame accuratly.

 

[Tony P]

Ok yes. So he did use all the same size blanks. Right, I can make several sizes of blank, center and one or two sizes for the hull ends. The joints though unless I figure out where they lay and make them approximate they’re not going to be the sane as the plans. It’s double framed butted, floor side had half floor side so the joints are in different places on either side. Having the joints where they’re supposed to be is accurate, the hull will be only partially planked.

 

[Dave Stevens (Lumberyard)]

what Harold did was to make the frame material wide enought to fit all the frames rather than make a bunch of blank patterns



with just two frame blanks you can make all these frames



if you make a blank pattern for a few frames per blank you do not need wide material

what i do is use the plastic from food containers and lay out the blank pattern


then trim the pieces where i want the joint to be



then i check how many frames i can cut from the blank before i have to make adjustments.



you need patterns for both halves of the frame.

sometimes you can use the same pieces and shift the joints to accommodate other frames, sometimes you have to just make a new blank pattern.

 

[Dave Stevens (Lumberyard)]

once you have your patterns i lay them out on the framing material


and cut them apart notice i do not cut on the line


next is to assemble both halves of the frame



then glue the blanks together to form on complete frame



using a blank there is no assembly of all the frame pieces that has been done with the blank so you glue the frame pattern to the blank


and it will look like this, you can see with the extended upper section of the frame you are using more wood. But if you are not building up side down in a jig you do not need the extended upper part of the blank. i find it so much more accurate to cut out the entire frame shape as apposed to trying to assemble the frame shape.

 

[Tony P]

Thanks Dave, I’m in the process now. Using green and red the same colors as Adrian’s book uses and that I colored my plan copies in.
I don’t understand your statement “you don’t cut on the lines”. Why not and when do you cut on the lines ? Also to get the joints in the ballpark with the plans you just draw them on the blanks ?

 

[Tony P]

I see Dave that’s why the clear plastic. Got it .

 

[Dave Stevens (Lumberyard)]

I see Dave that’s why the clear plastic. Got it .

those clear plastic lids that cover pies and cakes are great, i went to the local grocery store and ask the person in the bakery dept if i can have a few of those covers. I got a funny look but i also got the lids.

 

[Dave Stevens (Lumberyard)]

I don’t understand your statement “you don’t cut on the lines”. Why not and when do you cut on the lines ?

here is my method

once i have the blank patterns i mark them out on the framing stock



next i cut the pieces apart not cutting on the line. you can cut on the line if you are using an angle guage set and the correct angle. I am cutting freehand using a bandsaw so the cut tends to wiggle.



once i have the pieces i sand them straight and accurate using the angle guage



you may not notice when cutting the angles the slightest movement holding the piece to the saw will result in a misfit



cutting freehand either on a tablesaw or bandsaw might give you a bad fit



all kinds of problem arise when cutting these angles



the reason Harold used just one or two blanks is because he made a jig to cut the pieces so everyone was perfect.
I will find pictures of his jig to post.

quality of the frames depends on how accurate you can fit the pieces, and i sand them not cut them.

 

[Dave Stevens (Lumberyard)]

i found the jig images

Harold was an engineer by trade and one heck of an artist

Harold's concern was to develope a system so the average hobby person or first time plank on frame builder can achieve results so he came up with this jig idea from start to finish.
Like i said he used just one maybe two blanks for all the framing to avoid having to create more jigs to cut out blanks. His thinking was end results and not the amount of wood it takes to achieve those results. So give and take sacrifice a little waste wood for an accurate build or save a little wood and do it the hard way.

Knowing Harold personally and having him teach me sometimes it got a little to, hum how should i say it? tedious to the extreme.
Well he was an engineer and detail and accuracy was his thing.
all the framing material was exact width to fit the jig every joint was perfect
maybe that is why his models sold in excess of $35,000.00 they were works of art/engineering

 

[Don Case]

once you have your patterns i lay them out on the framing material

View attachment 343712
and cut them apart notice i do not cut on the line
View attachment 343711

next is to assemble both halves of the frame

View attachment 343714

then glue the blanks together to form on complete frame

View attachment 343713

using a blank there is no assembly of all the frame pieces that has been done with the blank so you glue the frame pattern to the blank

View attachment 343716
and it will look like this, you can see with the extended upper section of the frame you are using more wood. But if you are not building up side down in a jig you do not need the extended upper part of the blank. i find it so much more accurate to cut out the entire frame shape as apposed to trying to assemble the frame shape.

View attachment 343715

So, did Hahn not bother with chocks in the frame? Fitting them in after the halves were glued together would be a pain.

 

[Dave Stevens (Lumberyard)]

most of his models were North American built ships chocks were not used in the construction of American or French ship. I could be wrong but the use of chocks was a British thing.

however Harold did not use chocks in his Alfred model and that was a British built ship. I think he simplified construction so the average builder could build a model.

that is why i asked how these frames were built because your right i do not think the blank method will work with chocks

 

[Don Case]

Thanks Dave

 

[Tony P]

Ok Dave yes got it. Rough cut then fine tune the joints. Will do. I got a couple plastic lids from the wife might have enough. If I redo my measurements I can do all the same size blanks as of now I have 3 sizes. Yes that jig would work great no doubt. Either way this is going to speed up the process, a lot.
I don’t usually care about time in modeling but this is a long term project so time saved is time saved. There will be no chocks in Le Rochefort anyway so that’s an issue I don’t have to worry about. Thanks

 

[Tony P]

most of his models were North American built ships chocks were not used in the construction of American or French ship. I could be wrong but the use of chocks was a British thing.

however Harold did not use chocks in his Alfred model and that was a British built ship. I think he simplified construction so the average builder could build a model.

that is why i asked how these frames were built because your right i do not think the blank method will work with chocks

Dave, I cant see or cant figure out, are you putting the joints exactly where they are on the frame plan ?? I cant see how that's possible because we don't have the frame cut down to its actual size. I'm doing it now with the plastic. hmmmm ?