Jump to content

Schooner Germania (Nova) by KeithAug - Scale 1:36 - 1908 / 2011


Recommended Posts

Those rubber donut and springed sheet horses are quite common on larger top-end yachts of the "Golden Age," but I never really understood the point of them. I've never come across anything on them in the literature. Maybe they were a fad and wealthy owners commissioning their yachts came to expect them, so the architects satisfied their expectations. They are unquestionably impressive, but the springs I've seen have always been quite strong. You'd have a hard time compressing one by hand, and the rubber donuts were hard, like tire rubber, and no more "compressible" than the springs. (After a few decades in the weather, the old rubber was hard as a rock, too!) Maybe they served to remind helmsmen that in boats of that size an uncontrolled jibe was to be avoided at all costs, but in the event of one, those shock absorbers wouldn't have made much difference. Generally, the stretch in the sheets and the flexibility of the spars provide all the "shock absorbing" that's needed in regular operation. (The stresses aren't sharp shocks, like when tires hit potholes, but rather fluctuations in tension.) On the other hand, they may have been developed to compensate for the lack of stretch in more modern construction when wire cable standing rigging and better cordage with less stretch came into use (and certainly later, when synthetic cordage came along.) I do recall an old timer from the "Big Boat" ocean racing fraternity telling me how a lot of the large ocean racers suffered a lot of busted gear, broken frames, deck leaks, and such when everybody went to Dacron line and sailcloth and hydraulic backstay tensioners and big geared deck winches to squeeze a bit more speed out of their boats. They were then able to really crank down on the rigging far beyond what the boats had ever been engineered to handle. Those "buffered" sheet horses may have been some attempt to compensate for some of that. I don't know, but they are certainly an interesting and impressive fitting.

Link to post
Share on other sites
10 hours ago, Bob Cleek said:

They are unquestionably impressive, but the springs I've seen have always been quite strong. You'd have a hard time compressing one by hand, and the rubber donuts were hard, like tire rubber, and no more "compressible" than the springs.

Bob - I would agree that these shock absorbers are unlikely to be of a lot of use in and uncontrolled jibe. I once sailed on Simon Le Bons yacht "Drum" (fortunately not at the time she lost her keel). At the time she had huge plates welded on to either side of the main boom to repair the damage caused by an uncontrolled jibe. According to there skipper the jibe had bent the boom through about 45 degrees - remarkable given its very ample section. However it is my experience that even a controlled jibe in inclement weather can lead to boom whipping across until restricted by the main sheet. Under these circumstances both rubber and spring types of absorber will act to mitigate / reduce the instantaneous impact load. The loads on a big yacht can be many tons and ones inability to compress springs by hand is understandable. I agree with you that age hardened rubber wont work and my assumption is that the donuts have a recommended replacement cycle.

Link to post
Share on other sites

Back to the build after the shock absorber discussion. Thank you for all the comments and thumbs ups. 

I realise I didn't post any images of the finished rails ( after 4 coats of poly).

fullsizeoutput_2007.jpeg.dfddc13f07baa20ca3bac70a71558dae.jpeg

fullsizeoutput_2008.thumb.jpeg.b791f568f788ff9d9dd3cf796f52cb9a.jpeg

Having completed the rail I decided to make and mount the brackets for the shrouds - 4 each side for the main and foremasts - 16 in total. Similar brackets also attach blocks to the rail - 4 for each mast - 8 in total. I therefore needed 24 brackets.

fullsizeoutput_1f87.jpeg.7181b969a704ba8e26be734b87c49b26.jpegfullsizeoutput_2009.jpeg.5045abfc2afa0e5585e6404f2ebaa95d.jpeg

I started with a sketch. The brackets are fairly simple affairs:-

fullsizeoutput_1fb4.thumb.jpeg.b6d2bf0e85c797bf3fa999ac13bf9527.jpeg

I drilled a piece of brass to create the holes and then used these holes as a reference to mill the outer radius. A slitting saw was then used to divide each bracket.

fullsizeoutput_1fa7.thumb.jpeg.2904da29ef6945b0962241d403cf0d38.jpeg

The "comb" was then turned horizontal and a further slitting saw cut was used to separate the "fingers".

fullsizeoutput_1faa.jpeg.7bd2debc4f438058cff1ef08e1b1998a.jpeg

I then needed to attach a spigot ready for attachment to the rail. This involved drilling a .04" hole along the axis of the bracket. To do this i made a simple holding jig - basically a "U" shaped notch .05"  deep in a piece of scrap aluminium.

fullsizeoutput_1fa8.thumb.jpeg.3037d150fdbb9887e6c192a4855a5fa0.jpeg

fullsizeoutput_1fa9.jpeg.a5b4f09ccf1dd4ceabf78d13458d22fa.jpeg

The jig allowed the brackets to be positioned accurately and repeatably in the mill to allow the .04" hole to be drilled.

With all the drilling done .04" wire was glued in the holes to create the spigot.

fullsizeoutput_1fab.jpeg.044cabcaa90fd6ec633478bbce6f0d57.jpeg

Finally another simple jig was used to part off the spigots to length.

fullsizeoutput_1fac.thumb.jpeg.8f5d2cc18f4cd4849e23a70562137e8f.jpeg

fullsizeoutput_1fad.thumb.jpeg.efa9992285eb02508ab476aadaa803e6.jpeg

fullsizeoutput_1fae.jpeg.f374194247dd6fc1913dfb1e9be778e1.jpeg

I now have 24 ready to install.

 

 

Link to post
Share on other sites

Thank you Bedford / Mark.

 

3 hours ago, Mark Pearse said:

A question: do you think that glueing the rods in is stronger than solder, or is there another reason?

Mark. I find CA glue is very strong when gluing closely fitting shafts into bores. I even use it to glue parts on to shafts when I want to turn them and it invariably survives the turning operation. I don't think it is a strong as solder but it can be a bit more convenient and leave less of a clean up operation. 

Link to post
Share on other sites

Thank you Gary.

 

Progress seems to be slow at the moment, made more so by the sudden cold spell. Not much fun in the workshop over the last few days and hence limited time.

I applied tape to the rails in the areas of the shroud brackets and marked the centre line. While I was at it I started to glue in the winches.

I cross checked photos of the bracket positions against the plans and found them to be accurate.

fullsizeoutput_1faf.thumb.jpeg.40af16e81d37ff70a6ecf096afea0990.jpeg

DSC09829.thumb.JPG.795eef1b5fe29e4d7e27c205a11375c5.JPG

I marked off the positions for the brackets and drilled the rails to take the bracket spigots. The brackets were then glued in using CA glue. DSC09837.thumb.JPG.fee5aa61f7165e5302569a8c12a7a3b1.JPG

And a few more shots of the installed winces:-

DSC09840.thumb.JPG.cbc5ecd9054ecf6b872ec712efb3aeb8.JPGDSC09841.thumb.JPG.c1532261ab7e1fd753fed5157fe5d18d.JPGDSC09842.thumb.JPG.f1c36ba06bc8efc9bc4ef709b2cffc2b.JPGfullsizeoutput_1fb0.thumb.jpeg.e8bbffb691bf3feb5261b62b04bfbfe7.jpegfullsizeoutput_1fb2.thumb.jpeg.4ec6a74f9f412fab6a747214a4519fa7.jpeg

 

 

 

Link to post
Share on other sites

The weather has been somewhat on the cool side and as a result the workshop has been declared out of bounds. I have consoled myself by sitting in my arm chair planning the next steps and making manufacturing sketches from my stock of photographs. I have been focusing on the foredeck and in particular the various features around the anchor chain.

In the next photograph you can see a pair of bollards and a couple of chain guides hiding under a plastic canoe.

fullsizeoutput_200e.jpeg.e023ffb6d5f1c55ac57e16c2a7126907.jpeg

Here are the same features with their location better defined albeit with a loss of detail.

fullsizeoutput_200d.jpeg.cb9c1eff7af2cc3af4b9b0b90d8ab96b.jpeg

The rear most pair appear to be fixed guides and scaling of the photographs enabled me to produce the following sketch.

fullsizeoutput_1fb5.thumb.jpeg.052a16e0554ee4950f99899c1f1aabb2.jpeg

The front pair are quite tall and slender. The lugs will make manufacture of these somewhat more than a simple turning job.

fullsizeoutput_1fb6.thumb.jpeg.4faf0490dae3a6dd5a9c45cf6039f5ec.jpeg

Finally I returned to the "chain locking device" that was the subject of a previous discussion.

fullsizeoutput_1f54.jpeg.336a3223f0ca647781d902d2d6e6a687.jpeg

I took the advice that this was some sort of pawl lock and I imagine that it operates something like the depiction in the following sketch.

fullsizeoutput_1fbb.thumb.jpeg.329c6562862f53d9d544be3e89a91b1a.jpeg

Scaling from photographs produced the following sketch.

fullsizeoutput_1fba.thumb.jpeg.d9d2dc54d8579e42db80d84f0b77382a.jpeg

The weather is forecast to become more stormy and a little warmer so I hope to manufacture these items over the weekend.

Link to post
Share on other sites

The workshop conditions over the weekend have been tolerable so I have done a bit more brass work.

 

The chain guide bollards were a straightforward turning job. The only complication was I needed rather small turning tools so a bit of grinding was necessary. In the photo they are temporarily placed on the deck minus their circular wooden plinth which will be made later.

DSC09848.thumb.JPG.19600c5e8e1af1fb250016f6609e9c23.JPG

Having scratched my head for as bit I decided that the lug on the slender bollards would be more easily created if I made the bollards in parts with a split at the lug position. I therefor turned the top portion and then cut a slot to take the lug. The lug itself was milled to shape and then parted off to thickness. A 1/16" central hole was drilled along the axis of all parts for location purposes.

fullsizeoutput_1fb7.jpeg.14c71e54adad04ac330eed586308da4c.jpeg

DSC09854.thumb.JPG.b13706b18060a0195726abeeb554087c.JPG

The lower section of the bollard was then turned and its square based was milled. All parts were assembled on a central rod and glued with CA glue.

DSC09855.thumb.JPG.9d3ae35c65351cc47f75502fd938a3a0.JPG

DSC09857.thumb.JPG.09c696bf1f96af031c792a23aea5c281.JPG

I then made a start on the chain lock. I decided that I could make the 2 pawl devices from a piece of brass bar of 1.0"x.55"x.25". 

fullsizeoutput_1fbc.thumb.jpeg.a5862f1f7d9a6d872c75a4ff571494a9.jpeg

DSC09866.thumb.JPG.3ad2084468d8dbe163659a7d3fe8a7db.JPG

I needed a thickness of .2" so I reduced the thickness with a fly cutter. I then drilled the 2 off 1/16"holes for the pivot point of the pawl. fullsizeoutput_200f.thumb.jpeg.89891afb0c70f51d1c09ab6e130d7dbd.jpeg

I then cut off the waste material.........plus some that wasn't waste material..............the cutter slipped in the collet. So the plan changed to making 1 pawl device from the piece of brass.

fullsizeoutput_1fbe.jpeg.4720aa886936da74b816732e68952b8e.jpeg

I milled the circular profile by pivoting the brass in the vice around a central pin (actually a 1/16' drill) - taking a succession of horizontal cuts will the end mill.

fullsizeoutput_1fbf.thumb.jpeg.3cac6c3aecc000206c81c8ae29cd4bf8.jpegfullsizeoutput_1fc0.thumb.jpeg.8b88532c971dec50fdd2f4f234378c1f.jpeg

With a light filing I had the desired circular form.

fullsizeoutput_1fc1.thumb.jpeg.c5df7dd544f598659fe05b6c2788ddd5.jpeg

I then slotted out the centre using a slitting saw.

fullsizeoutput_1fc2.thumb.jpeg.c0b83f67c1acb4e8e31e32f36df30d7b.jpeg

I repeated the process to create a second pawl body.

fullsizeoutput_2012.thumb.jpeg.a6766e607a793659c738c3b3214e4b5a.jpeg

The two parts were then aligned through the pivot hole and stuck together using double sided tape.

fullsizeoutput_1fc5.thumb.jpeg.7fab98e99dcfbb2d3bbc58381d2e429d.jpeg

It was then back to the mill to cut the ramp angle on the in-feed side.fullsizeoutput_2013.thumb.jpeg.0fd82f0188225776cbbfd6e3eb35fa0d.jpeg

With the ramp cut the two parts were cut off to height with a slitting saw.

fullsizeoutput_1fc7.thumb.jpeg.716df45034b9cc433938741626a9031b.jpeg

fullsizeoutput_2015.jpeg.0259c8fe1cbbe2ec9a976aa8277a4b62.jpeg

I hope to finish tomorrow.

 

 

 

Link to post
Share on other sites

Coming back to the lugs for the shrouds etc. (have been travelling last week and couldn't follow progress): how would they have been attach to the bulwark on the prototype ? Somehow, I would have expected some sort of chainplate to distribute the stress or the stanchions taking this function (albeit they are leaning the wrong way for this - or perhaps the right way in order to prevent the bulwark being pulled in by the shrouds).

 

No comments on the metal-work ;)

 

Link to post
Share on other sites

Eberhard. I don't have any decent photographs of the area as it is very congested - lots of blocks and halyards obscure the view. The plans show reinforcing steelwork between the lugs and the deck - although not in enough detail for modelling.  As it wont be visible I don't plan to reproduce.

 fullsizeoutput_2029.jpeg.dc206f3f7ddeaafe0e8860bdb17a3208.jpeg 

Link to post
Share on other sites

It is pretty miserable outside today but at least the workshop is sitting at a comfortable 9c (48f). 

I made the pawl handle from a scrap bit of square section tube .250" outside and .025" wall. I cut a piece of mahogany .2" square and glued it in the tube to provide strength while I machined it. I then drilled a 1/16" hole towards one end to create the pivot point for the handle. I then drilled a second hole in the side furthest away from the pivot holes to take the eyebolt. I then parted off the handle to the required width (0.1") on the Byrnes saw fitted with a slitting saw blade.

fullsizeoutput_1fc9.thumb.jpeg.5fa0c5a80a8d42e9dd229e7c2b6a8ace.jpeg

I then hand filed the end with the hole to form the radius and remove the adjacent side. I then threw it away dissatisfied with the accuracy of my filing. I repeated this whole process a second time with the same result. I was taught many years ago how to file perfect radii but I had never tried it on such small parts (.05" radius). Anyway I made myself some filing bobbins from mild steel and did the job properly.

fullsizeoutput_2016.jpeg.36e091ac5a32f00cbfc44cab296f5543.jpeg

fullsizeoutput_1fce.jpeg.af564bcc0c0dcc150686c7ca278d6ad4.jpeg

fullsizeoutput_1fcf.jpeg.714cd956cbefa63fc33c1c4beaa5f212.jpeg

I did a test fit on the pawl body and then went on to make the eyebolts (.09" diameter) as per the method previously described.

fullsizeoutput_1fd0.thumb.jpeg.5b0f844158c585272db902d6ada5184b.jpeg

fullsizeoutput_1fd1.jpeg.ab7acc3e020d4d3ed9efa708f4a901a6.jpeg

The eyebolts were then soldered in place. While I was at it I soldered a location spigot on the base of the pawl body.

fullsizeoutput_1fd2.jpeg.6d131b30aaf8f963fdff5dddb0a25bc4.jpeg

Finally I cut some 1/16" rod for the pivot and assembled the parts.

fullsizeoutput_2018.jpeg.3196396a7e5f46089382db87af9b7d3b.jpeg

The small chain rollers were then made - not much explanation needed as the photos say it all.

fullsizeoutput_2019.jpeg.0bde0a5b79185f12b07f07d410984daf.jpegfullsizeoutput_201b.jpeg.751f519b1f2f208ae18354e090dc338e.jpegfullsizeoutput_201c.jpeg.18915b7759e6b2b5c81a482396bdeed5.jpegfullsizeoutput_1fd9.jpeg.2b20db9869f65e34149ee1179deea1e0.jpegfullsizeoutput_1fda.jpeg.8562d8a8649dd9c4f19870c293e80c4e.jpegfullsizeoutput_1fdc.thumb.jpeg.114ad813cf638a93332462214526e08a.jpeg

I then got on with fitting the various parts to the deck.

The wooden plinths were made and positioned using card templates.

fullsizeoutput_1fdd.thumb.jpeg.8aa85324ff446271e3ba6ebef4298a3d.jpeg

fullsizeoutput_1fde.thumb.jpeg.69780ac9e08b198bea64bde967192e7d.jpeg

The positions for the chain pawls were likewise located using a template.

fullsizeoutput_1fdf.thumb.jpeg.07feca473a68e07afddf3ec0ff328457.jpeg

The pawls and chain rollers were then glued in place.

DSC09910.thumb.JPG.426c146ca4799e9d52f6c1fdc4feffc9.JPG

DSC09919.thumb.JPG.f7e72b9e1ffdf162801fc546f07eb678.JPG

Finally I found a bit of chain and tested the run. 

DSC09921.thumb.JPG.8429d554777efa30d2f520fa065ae92b.JPG

The chain is a bit large really. It has 11 links per inch and I think I will try something smaller before I commit.

Link to post
Share on other sites

9°C being 'comfortable' ? That's just above freezing ! You Brits are crazy (at least concerning temperatures) - but I knew this from my years in Nottingham (when I first moved up there and looked for a place to rent, I visited one that was advertised to have 'central heating' - well it hat a single gas-fire that was located centrally in the apartment ...).

Link to post
Share on other sites
5 minutes ago, wefalck said:

9°C being 'comfortable' ? That's just above freezing ! You Brits are crazy (at least concerning temperatures) - but I knew this from my years in Nottingham (when I first moved up there and looked for a place to rent, I visited one that was advertised to have 'central heating' - well it hat a single gas-fire that was located centrally in the apartment ...).

6 degrees in my garage this afternoon after work, managed 45 minutes, that was it!

 

Link to post
Share on other sites
1 hour ago, paulsutcliffe said:

what's a file bobbin?

Paul - Michael is correct and bobbin and button both seem to be used. Ideally they should be left loose on the shaft so they can rotate. Once you have filed down to the bobbin / button it rotates and the file rolls over it without cutting - hence you stop cutting the metal being filed. 

Link to post
Share on other sites
1 hour ago, paulsutcliffe said:

6 degrees in my garage this afternoon after work, managed 45 minutes

Yes Paul - its amazing what a few degrees can do. I too find 6 degrees pretty uncomfortable. The temperature seems to have been dropping throughout the day so tomorrow may be a workshop avoidance day.

Link to post
Share on other sites
10 hours ago, BANYAN said:

or other solution

Pat:_

-1219474971_Screenshot2020-01-28at09_28_45.png.cc8f820f9627f93f98b183dab9bb419c.png

10 hours ago, Bedford said:

happily wear shorts and T shirt at 9 degrees, luxury!!

Tough you is Bedford.

10 hours ago, Jim Lad said:

If you're not liking your current cold spell you could send it over here

John - Cold is fine - its the overcast greyness that really depresses. Fortunately today its wall to wall sun - but very cold.

 

thankyou all for your feedback.

Link to post
Share on other sites

For a while I have been thinking that the bowsprit foot would make an interesting project and so I decided to tackle it next.

fullsizeoutput_2064.jpeg.dd65d90f12e14a2c3434182cf55791c1.jpegfullsizeoutput_2066.jpeg.494b7a5e50b24ee724cae3292042f3ec.jpeg

I find that solving machining problems is a lot of fun and in this case the step in the profile of the foot (Item A) caused a bit of head scratching. The oblong boss (item B ) was a lesser problem to resolve.

The brass name plate at the back of the foot is quite nice but at scale size the larger letters are circa .05" high so I don't think I will be trying to reproduce them.

fullsizeoutput_b95.thumb.jpeg.67695fb1cc4a2fe659ef303bf6b491f5.jpeg

Through a combination of plans and photographs I was able to sketch and size the foot.

fullsizeoutput_200b.thumb.jpeg.5f4840d4662b624070bad598cfc45463.jpeg

fullsizeoutput_2061.thumb.jpeg.cd5c7c00b1be7d64be8e286f37865dce.jpeg

I decided the best way to produce the step was to make the foot from 3 parts labeled 1,2 and 3 in the sketch. The foot on Germania is made from a silver coloured metal which could be stainless steel but my guess is it may be aluminium. The colour makes it quite a pronounced feature so I decided to reproduce this by making the foot predominantly from aluminium.

 

I started the manufacture by cutting a 0.650" wide block from a 2" x 1" piece of aluminium bar. I just love hacksawing thick metal sections like this!!!!!! Having cut the block I reduced it to .55" wide by .775" high by 2" long.

DSC09926.thumb.JPG.1cf6ba7030546e11b52bbd8ad83dabbc.JPGDSC09927.thumb.JPG.0191412c9de3909cda7ca5e7bb8469ad.JPG

I then drilled and reamed a 6mm hole through the block .5" from the narrow edge. Apologies for the mixed units my reamers are all metric.

fullsizeoutput_1fe3.thumb.jpeg.2b95606e756244d4a4feb5373cf4406f.jpeg

I then used the reamed hole as the location for milling the outer radius of the top. 

fullsizeoutput_1fe4.thumb.jpeg.99291a30c6e426949f843df9c0d2492b.jpeg

fullsizeoutput_1fe5.thumb.jpeg.0bbfd6a84b09a51fa11c656830ea691e.jpeg

The next step was to slice off and finish to thickness the central part of the foot - item 1 in the sketch. With this removed the surface of the remaining material was reduced by .025".

fullsizeoutput_1fe7.jpeg.f5c3d7da0f013f4652dab03f2407ad3d.jpeg

A further slice was then cut off and finished to size to create item 2.fullsizeoutput_1fe8.jpeg.f39f13520265d09c82883b1d4eae404a.jpeg

The next step was to start profiling the shape of item 3. To do this I needed a 1" diameter cutter. As I don't have one I used a fly-cutter instead. I set this up by positioning the centre line of the cutter spindle directly above the edge of the machine vice and then indexing across by .5". I then set the fly cutter blade against the side of the vice to give me a fly-cutter diameter of 1 inch.

fullsizeoutput_1fe9.thumb.jpeg.64cc4f1b2b4995b30be59b290d004a41.jpegfullsizeoutput_2020.thumb.jpeg.af2fd1b109c5a606df7df87d108f511b.jpeg

fullsizeoutput_2021.jpeg.07483c60e43c08f426c7f62c877c162c.jpeg

The kick up at the front was then removed on the mill before the curved face was finished by draw filing.

fullsizeoutput_2022.jpeg.7a9dd1372c1cd6e203e398c8a00153e5.jpeg

Part 3 was then glued to a 6mm steel rod and transferred to the lathe.

fullsizeoutput_2024.thumb.jpeg.41ac15c38bfe66d5e5572ccead1d932e.jpeg

Here the face of the 6mm hole was cut back with a boring tool to form a flat seat of the bowsprit.

fullsizeoutput_2025.thumb.jpeg.152536ad3c97da8c49a1b941d56fd4f7.jpeg

With this done I applied a little heat to break the glue bond and then hacksawed and milled part 3 to length. Finally I removed the centre of the foot to form 2 toes and drilled the holes for attaching the belaying pins.

fullsizeoutput_1ff0.jpeg.6dcf4ba31f8355f4e6949530fac26eb2.jpeg

The part finished foot was then assembled. I hope to finish it tomorrow.DSC09950.thumb.JPG.7d9183f299e5b403f9fa77cc38896aeb.JPG

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...