Framing around a gun port

[Don Case]

I'm starting to glue in square frames on the Discovery1789. The first ones have a gun port. My R&S is 28", frames are 11" and the gun ports are 29". The drawings show that one side of the port is up against a frame but that leaves the other side kind of hanging out in "space"🙂 I've seen offset frames but this is too much to offset I think. The picture shows the frames and the piece of masking tape is about 1/8" narrower than the gun port. The R&S is speculation so I could change that a bit. How do I frame that?

[iMustBeCrazy]

1 hour ago, Don Case said:

I've seen offset frames but this is too much to offset I think.

Don, sometimes it's just messy.

 

This is Speedy 1828, the R&S varies 25", 23", 21", 23", 25" while the ports are a nominal 21". It just cannot be done neatly, I tried and failed. The futtocks have to be stepped and or lean to suit the spacing of the gun ports.

 

 

 

 

[Don Case]

That's really surprising but I guess even spacing of the guns was important so the crews had equal space to work in. Was it that important to have a full frame on either side of the port? I was thinking something like this might be the answer. Excuse the primitive "CAD" work😉

Edited April 18, 2021 by Don Case

[iMustBeCrazy]

11 minutes ago, Don Case said:

Excuse the primitive "CAD" work

Hey, it gets the point across admirably.

 

12 minutes ago, Don Case said:

I was thinking something like this might be the answer.

I suspect this would give uneven loading on the breeching lines but others will know better.

[Don Case]

8 minutes ago, iMustBeCrazy said:

Hey, it gets the point across admirably.

 

I suspect this would give uneven loading on the breeching lines but others will know better.

Good point, I never thought about breeching lines. Actually I had to look up what they were.

[Jaager]

The bulwark framing on the cutter is spare when compared to large vessels.  In most cases, there was planking inside as well as out. 

The tops and half tops are hidden and filler material can be used.  The English seem to be alone in going out of their way to position the framing to be the actual sides of the ports.  North America and France appear to have more material and just cut away what is in the way of the ports and add more in between.  There were rules for the spacing of the ports as well as size and height.  I think Davis gives a 1750 English rule - based on shot diameter.

 

One aspect that a lot of kit builders seem to ignore is -  well, look at the cutter plan -  the sills and lintels are parallel to the deck sheer - the opening only has right angles in the midship port or two.  The rest are parallelograms.

[allanyed]

Don, 

The spacing between ports was not always the same.  It could vary by as much as 10" round the area of the main mast.   The space between frames for the ports themselves for a given deck on a given vessel was always the same so there was no need to cut into a frame as you show, thus weakening it.  The frames were reduced in siding as you went up each futtock and they were offset as well, to create the proper width between frames so each gun port on a given deck was the same.   There were small (about 2" deep) mortises cut into the frames for the sills.  The  sills sometimes had a birdsmouth mortise and at other times an angle mortise.  This varied from ship to ship as some had angled mortises for both the upper and lower sills.   The following is just one example, but there are many more that can be found at https://commons.wikimedia.org/wiki/Category:Ship_plans_of_the_Royal_Museums_Greenwich  as well as the NMM site.  This particular one was taken from the commons.wiki site as it is a high res version.   Even with the low res versions you can download for free from NMM, you can see that the space between ports is sometimes  the same, sometime not.  You can also see a variety of the offset frame construction so no big chunk needs to be removed from any frame.  For a much clearer look at the vessel drawing below go to https://commons.wikimedia.org/w/index.php?title=Category:Ship_plans_of_the_Royal_Museums_Greenwich&fileuntil='Impregnable'+(1810)+RMG+J1643.png#/media/File:'Aquilon'_(1786),_(also_spelt_Aquillon_or_Acquillon)_RMG_J7958.png  The spacing between ports on this vessel happens to be consistent.      

Hope this helps.

 

 

Edited April 18, 2021 by allanyed

[druxey]

Sorry, Don, but in English shipbuilding what you show was simply never done. The timber on each side of the port needed to be strong, as the bolts of the breechings - which absorbed recoil of the guns - and training tackle were attached through them. Therefore maximum strength was required of these timbers. Your version would give way at the first shot. Study contemporary framing diagrams such as the one Allan has posted carefully to begin to understand actual framing practice. There's lots to learn, trust me!

[Don Case]

I'm confused. I went looking in "Scantlings". The sorta average R&S is around 26" or so. The sorta average sided dimension of a frame is around 12" or so. So they are very roughly 50/50 room and space. Then I look at the "Aquilon" and its almost solid wood from stem to stern. There is very little "space". What am I missing?

[allanyed]

Hi Don

 

I cannot speak for ships of other than English,  but for those, simply put, R&S includes two frames and the small space between them and the next pair.   There is no big gap between frames.  Goodwin explains as follows on page 13 in The Construction and Fitting of English Man of War.

 

....stringent rules establish the distances between each 'main' frame so that this (ventilation) could be achieved.  This was known as the 'room and space' provision, and measured the distance between the face edge of one complete (or main) frame and the equivalent face edge of the next main frame.  The measurement can be roughly estimated as twice the fore an aft breadth of a single frame plus between 2in and 6in for the overall small spaces between the filling frames and and main frame. 

 

This is a bit difficult to be clear in words.  Look for drawings such as those posted above which explain the lay of frames as they should be.  The drawing above is contemporary and correct.   If you are looking at contemporary models, they are usually "admiralty style" and do not have frames laid as they were on the actual ships themselves so of no use in figuring R&S.  

 

I suggest you pick up a copy of Goodwin's book as it is a great source on the basics of English warship construction between 1650 and 1850.  

Edited April 18, 2021 by allanyed

[Don Case]

English is good, one country at a time🙂 I think you're getting me on the right track. I had it stuck in my head that R&S was one single frame and some space. I thought the " The measurement can be roughly estimated as twice the fore an aft breadth of a single frame plus between 2in and 6in" was just that, an estimate of the R&S. So now I have to decide between real and Admiralty. Real means making another 35 or so frames. I think I'll do some looking at Admiralty, I was looking forward to gluing in some frames and I actually have glued in all the cant frames. HMmmm

Thanks I think I just learned something.

 

[druxey]

Don: the math of room and space is (in your quoted example) 12" plus 12" (a floor + a first futtock) which is 24". This leaves a mere 2" of space to make the 26" of R & S. As Allan suggests, you really need to read up on all this to understand the construction of a wooden vessel. The one exception will be at the dead flat frame. This was either single or triple (occasionally even quintuple). It was always an odd number so that the floor changed sides on the frame pairs at that point along the hull. There is so much more to the business of framing, as I hope you will discover.

[Don Case]

Yeah, I just start to think I'm understanding this and then read something that puts it all in doubt again. Everyone says things slightly differently so I'm having a tough time wrapping my head around it.

 

You wrote " (a floor + a first futtock)=24" ". I thought a futtock went on top of a floor. Back to the books😕 

[Don Case]

I'm looking at Longridge pg 19 Fig9. It's labeled as "Normal Admiralty System". Does this mean the way models were built or the way the real ships were built? I can see now what you're talking about with a floor and the first futtock. I've looked at this figure a dozen times and never quite understood. In the text on pg18 he says each frame has two floors. Is that little chock-like thing in the figure considered a floor timber. His arrow denoting "floor" doesn't point at it. So we would have one long and one short floor timber and then the futtocks alternating single frames up to the top?

[allanyed]

Don,

This may help understand a little better.  These are two frames that sit next to each other.  

[druxey]

Just to clarify the above: the two 'slices' together make up a frame pair. However, in some cases (this will drive you crazy) the slices were separated by small chocks to allow more air circulation. 

 

[Don Case]

Thanks to all you guys for taking the time to try and clue me in. I think I'm making progress. Unfortunately I think it means making another 34 single frames, the second half of the ones I've already done. I think these will go a little faster as I now have a pattern for each. I'll use a lot less wood too. I may have to live with single cant frames as I've already glued them in.

[allanyed]

Another 34 frames is good practice for future builds!!!   Look at all the experience you are gaining from asking and then doing, and think about how much more confident you will be on the next project.  You are getting information from hundreds of years of collective experience from the members here.  Many of us wish we had had this kind of access to information when we were on our first projects, so know that you are a lucky guy. 

 

[Don Case]

Oh, I know that!!🙂 I'm not sure I'm building the frames right. Maybe I'll show how I do it on my log.

[mtaylor]

3 hours ago, Don Case said:

Oh, I know that!!🙂 I'm not sure I'm building the frames right. Maybe I'll show how I do it on my log.

That would probably be an ideal place to show it.  

[Don Case]

I've done a little on the log but I don't seem to get questions answered there. If I want to be sure of an answer I put the question over here. I really haven't figured out what the log is for.

[allanyed]

Either way is not so bad.  I have often done the same thing.   I have not seen any posts  on your log for the past two weeks though.  Maybe give it a another try.   Better to ask twice and get a response from one forum than post on one forum and get no responses 😁

[iMustBeCrazy]

Don, another thing to note is the the 'frame pair' at station 0 was often a triple or single frame not a pair. This reversed the way the frames in the pairs were arranged so that the same half was always closest to station 0.

 

Speedy (cross piece of each pair closest to station 0):

 

 

Aquilon (NON cross piece of each pair closest to station 0):

 

 

[Jaager]

The French seem to have been somewhat obsessed with mirroring the floor timber orientation at the midline.  They also seem to have used all bends (paired frames).  In North America, my observation was that an orientation was chosen and it was maintained from AP to FP.  After The Revolution there was not often the midship nonsense.  If there was, a close together double line of stations seems to be on the plans.  The English did not always use all bends.  In fact, it is my observation that it was a bit rare.  They most often used two bends per station and filling frames inbetween  or a bend per station and the rest filling frames.  If there was an odd number of filling frames, the alternating of floor timbers with F1 overruled any fore and aft orientation.  There was an evolving change from 1719 thru the Napoleonic period - when the number of ships was increasing and the supply of timber was decreasing.

[Don Case]

2 hours ago, allanyed said:

Either way is not so bad.  I have often done the same thing.   I have not seen any posts  on your log for the past two weeks though.  Maybe give it a another try.   Better to ask twice and get a response from one forum than post on one forum and get no responses 😁

I have been messing with these frames for two weeks and not really gaining ground until the last couple of days. I  thought of asking twice but I thought that would be frowned on.

[Don Case]

1 hour ago, iMustBeCrazy said:

Don, another thing to note is the the 'frame pair' at station 0 was often a triple or single frame not a pair. This reversed the way the frames in the pairs were arranged so that the same half was always closest to station 0.

 

Speedy (cross piece of each pair closest to station 0):

 

 

Aquilon (NON cross piece of each pair closest to station 0):

 

 

 

Cross piece??

I've noticed that station 0 got a little crowded at times. 🙂 Why would they care if the frames were facing the same direction?

I decided I was going to study the Aquilon to see how things went and I got all caught up in trying to read the numbers of the sections and the scale. I still haven't sorted that out. Old English numerals, is there such a thing?

Edited April 19, 2021 by Don Case

[Don Case]

57 minutes ago, Jaager said:

The French seem to have been somewhat obsessed with mirroring the floor timber orientation at the midline.  They also seem to have used all bends (paired frames).  In North America, my observation was that an orientation was chosen and it was maintained from AP to FP.  After The Revolution there was not often the midship nonsense.  If there was, a close together double line of stations seems to be on the plans.  The English did not always use all bends.  In fact, it is my observation that it was a bit rare.  They most often used two bends per station and filling frames inbetween  or a bend per station and the rest filling frames.  If there was an odd number of filling frames, the alternating of floor timbers with F1 overruled any fore and aft orientation.  There was an evolving change from 1719 thru the Napoleonic period - when the number of ships was increasing and the supply of timber was decreasing.

How did the Spanish arrange them😃, no, wait, I don't want to know😵

[iMustBeCrazy]

52 minutes ago, Don Case said:

Cross piece??

Perhaps more often 'Floor' or 'Floor Timber', the pieces marked with an 'x'.

 

53 minutes ago, Don Case said:

I got all caught up in trying to read the numbers of the sections

They're beaut's aren't they, they read 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23,25, 27, 29. But no '0'.

 

 

 

 

[Jaager]

2 hours ago, Don Case said:

Cross piece??

Almost never did the ends of F1 right and F1 left abutt at the middle of the keel.  The ASA made a point of forbidding this in their rules.

A small center piece of timber = cross chock.

A larger timber over the keel = Cross piece

A timber that has arms that about half those of the floor timber = half floor.

Another way was to have F1-right side have an arm that extended across the keel an abutted F1-left on its side.  The next bend would be F1 left with the long arm .  This pattern would alternate.

 

I have no clue as to Spanish practice.  As far as I have seen, there has been no effort made to share the Maritime and Naval archives of Spain with the wider World with a push from their side.

France has ANCRE and AAMM.  But the AAMM plans that I have are aimed at a carved hull method of fabrication.  The subtext is that POF builders already know more than the authors of the plans about the method and are held a bit in awe.  The publication dates of AMM plans go back a ways and wide spread exposition of POF came after.