Medieval longship by bolin - FINISHED - 1:30 - based on reconstruction Helga Holm

[Schrader]

Take a look this other idea

 

I just took a sewing pin. I flattened in a belt sander. Made the head squared (very carefully) and blued.  The sewing pin should be iron. Not steel 

Edited October 31, 2020 by Schrader

[Schrader]

 

 

 

 

 

 

 

Edited October 31, 2020 by Schrader

[Schrader]

 

 

sorry if I am overwhelming you. But I though it could be useful

 

Edited October 31, 2020 by Schrader

[liteflight]

Thanks for the rove-making tutorial, Schrader 

noted and stored away for the riveting stage of my Oseberg ship

 

i like the rove-punching handle-  saves getting flat fingers!  It looks as it it was repurposed from something, perhaps a lace-making bobbin?

 

i will try making my own rivets from copper or brass  wire parted by rolling under a knife with a 90 degree edge.

[Schrader]

Try with a blind-ribet
 

this “method” is not mine. Take a look in Facebook - Liberto Amate Aguilar. His is a Spanish Modelist.  Really good an has a Viking 

[bolin]

On 10/30/2020 at 1:10 PM, Louie da fly said:

Walnut has a reputation of being easily broken and unwilling to bend without splintering. However, I'm using it on my Great Harry without much trouble, though my planks are pretty thin because the model is at 1:200 scale. What is the thickness of the planks on the Helga Holm?

The planking is about 22-25 mm in full scale, so just little less than 1 mm in my model scale. Since the ship is so long and narrow there will net be to much of bending, but a bit of twisting of the planks. It hope that it will be manageable, we will see.

[bolin]

Thanks for all your input on rivets Schrader. I have actually been searching for some tips, and your is by far the most detailed I have seen. Very valuable. Thanks.

 

I would like to use metal if i can find a reasonable process. There will be about 2000 rivets, so I need to find an efficient method.

[Louie da fly]

1 mm should probably be ok. My planks are about that thick and I only have trouble at the stern where the plank has to twist from almost horizontal to almost vertical in a very short length- which you probably won't have on your model. 

Edited November 5, 2020 by Louie da fly

[bolin]

As I have no disc sander, or similar machine tool, I have made a jig for sanding down the scarf joints. Its basically a sled with constant angle where I hold the piece with my fingers.

In the picture I show a piece that is the connection between the keel and the stern. Such a piece was found in the the archeological find, and in the report from the find it was called undirlutr. It is the Icelandic word for it. Its seem that such a piece has fallen out of use in traditional clinker built ships in the Nordic countries, so no word remains except in Icelandic.

 

The boat builder that built the reconstruction wanted to make the scarf joints longer, which would have made them stronger. But was ordered to build as the original, which I also will do. The scarf joint are about twice as long as they are wide.

 

Next, the joints can be glued together, below I show the stem. I glue the two pieces making up the the stern and stem together first, so that I can cut a rabbet while they are still laying on a flat surface.

I have also started to bevel the keel to meet the garboard at the correct angle.

 

With experience from my "practice build" Sloop from Roslagen I have devised a way to keep the keel fixed in place. I have added two brass pins in the building form, and corresponding holes in the keel. The pins are placed where the frames will sit, so the holes in the keel will be covered later.

 

Cheers

 

 

 

 

 

 

 

[bolin]

The rabbet line in the stem and stern should be "stepped".

This makes it a bit of a challenge to trace it to both sides symmetrically.

 

My solution is to put first put some tape to a sheet of plastic and trace the outline from the plan using bold lines. After that I put another piece of tape on the other side of the plastic and traced a mirrored copy.

I then lifted the two pieces of tape and put taped them to the opposite sides of the stem and stern.

 

 

[Schrader]

Really good Idea. I’ll try it next time. What I use to do is to join two pieces of wood with a doble side tape an work on them as they were just one. After you finished it you separate them and you have two identical pieces

[bolin]

Good idea using double sided tape.

 

I have carving away on the stem and stern pieces and have now finished the rabbet for the planking.

This means that the pieces are ready for joining with the keel. As can be seen in the picture below the fit is not as exact as I wanted. This means that the glue joint probably is a bit weak. To strengthen it I have added some tree nails.

 

So, now I'm finally ready to start planking. I have progressed slowly up to this point, so that I could continue with my other clinker model, the Sloop from Roslagen. I use that as a practice and to learn from my mistakes.

 

 

[bolin]

Before I started to cut the planks I cut a template from some card stock.

 

This helped me discover that the fairing of the frames closest to the bow and stern was not adequate. When fairing I had not taken into account that the rabbets makes the hull even narrower close to the ends. So I had to remove a bit of the material on the first and last mold frame. I also discovered that the rabbet needed to be a bit lower in the stem to let the plank run correctly.

 

After I had fixed these issues, I cut the first planks. There are very little shaping of the garboard plank. Its 8,5 mm wide along all its length, except for a slight tapering in the ends where it goes into the rabbets. Even so it took some work to get the the planks to the correct length to fit into the rabbets on both ends. When that was done I could soak the planks in hot water and bend it to shape in place.

One thing I think I saw, and need to check more, is that the plank seemed to be longer after I had soaked it. I would expect it to swell sideways, but not as much length wise. Maybe I cannot use soaking on walnut? Especially not for such long strips as these (over 50 cm).

 

 

[mtaylor]

That's possible I guess to expand slightly in length, but then, I've never done at check to see. On bright side, after it dries out, it should go back to the original length to be glued.

[bolin]

The planks did shrink after they dried. One was still to long, so I had to shorten it slightly to fit in the rabbet without bulging on the middle.

Before I install the next strake I will bevel the edge of the already installed planks to the correct angle. To do that I have made a special sanding block with the same width as the planks that I can run along the planke edge and ride on the frame molds. (I learned this method from @druxey in his excellent build log for the Greenwhich Hospital Barge.)

Each plank will also get a decorative groove along its length. In the original find, and on the reconstruction, there are three parallel groves.

I have made a small tool from a blade that I have filed down all but 1 mm of, and glued between to pieces of wood. I run i to run along the edges of the planks to create similar grooves. My tool creates more like a band, than three distinct grooves. But considering the scale and that the grooves are almost invisible in full scale, I'm OK with that.

[Louie da fly]

Nice work. You're taking it slow and carefully, and it shows in the result.

[bolin]

Thanks, I do want this to be a nice model. Since the reconstruction will soon no longer be in condition to sail, I build the model to have a something to remind me of all the nice times I have had onboard. In a way I have even planned my previous builds to learn the skills to make this a nice model. I hope I will succeed.

[druxey]

A little too long is always better than a little too short! Nice progress, bolin.

[bolin]

I cut the second plank and started to fit it today. There seem to be a problem. When the plank lies flat and nice on most of the frames it does not go into the rabbet.

There are some photos from when the reconstruction was built. The planks are quite straight, and used in more or less their full width all the way to the ends. They are only bent and twisted, no edge bending or splicing.

 

I have an idea of what my problem is, and I have created it myself:

 

On 10/23/2020 at 9:11 PM, bolin said:

After beveling the frames and checking again with a strip of wood I decided that I need to widen the first three frames and last two. I will start with 1 mm strips of wood on each frame. That should be enough in the aft, but may not be enough in the bow.

If I just bend and twist the plank as it naturally goes it could reach the rabbet, if the frames where narrower and the bow was more concave.

 

I will need to sleep on this.

 

 

[druxey]

You may find it easier to lay each strake in two planks so that they fit at stem and stern. Shape the plank ends first, then trim the butt joint to land over the center of a frame.

[bolin]

Thanks durxey, I will try that. It would also be more realistic as the real ship (both the original and the reconstruction) has strakes made out of more than one plank. My idea thus far has been to fake the joints by scratching a mark in the plank and add a number of rivets to indicate the joint.

[bolin]

Forth strake fitted, soaked and bent to shape on the mold. The third and fourth consists of two planks that are joined with a bit of overlap as on the real ship. This gives me some wiggle room in adjusting the length of the planks to fit in the rabbets. On the picture below I have not thinned down the end of the longer uppermost plank. I will do that when I have glued the first planks and know exactly what length the plank need to be.

 

 

[Louie da fly]

What kind of joint are you using between the two planks?

[bolin]

Its a scarf joint. I'm trying to replicate whats shown in the picture below. If you look carefully the joint, and the angle, can be seen.

 

[Louie da fly]

Very good. I was hoping that would be your answer. You're definitely on the right track.

[bolin]

I have been experimenting a with rivet construction today.

 

I think I have a method that will work OK for 2000 rivets, and can be made to look good scale wise as well.

 

First I drill holes for the rivets. I got a new drill holder for this, an "archemedean" screw type. I already have a pin vise and a Proxxon electrical tool. However I think my fingers will tire if using the former, and the risk of the drill jumping and leaving marks on the hull when using the second is to high.

A few holes:

The rivets are made from a dish brush bristle. They get a head by melting the end in a candle.

The rivets are then pushed through and the plate on the other side is added. These are made from painted cardboard and is given a small drop of glue beneath to stay in place. Scale wise the plates are too large, maybe I need some better cardboard.

The pins are then cut and the ends are flattened using a soldering iron.

The outside

The rivets should be about half the distance apart, but otherwise I'm quite happy with the result.

 

A picture from the reconstruction

 

[druxey]

Would thin brass or copper shim sheet work better than card for the roves?

[bolin]

That could probably work. I will see what I can find. I have also considered plastic sheet. The experimentation will continue.

[mtaylor]

Aluminum foil might also be an option but it is rather flimsy.

[Schrader]

What about this