Moonbeam

[BanjomanParticipant @banjoman]

Hello Bob,

I see! No, by "styrene" I did indeed mean plasticard – which is of course made from a form of styrene plastic. Polystyrene in the sense that you were talking about I do not think would have worked very well!

And yes M1.6 is indeed a fairly fine thread – although the chap in Germany, Dieter Knupfer, from whom I bought the die actually carries dies and taps down to M0.5 (**LINK**)! One day I intend to have all the sizes down to and including M0.5, but at 40 euros a pop for the "larger" ones, and 60 euros a piece for the M0.5 and M0.6 dies, I shall have to fall back on a fairly longterm aquisition policy (i.e. by them one at a time, as, when and if I need them).

/Mattias

[BanjomanParticipant @banjoman]

In between waiting for various things to go off, I have also added two rings to the winch loop, to which the various sheets will later be hooked on.

For this, I wanted to use solid (i.e. not cut-through) rings, and found a couple of Aeronaut ring bolts in my parts box, from which the eye hooks were easily removed.

I also located a spool of Mölnlycke "Grizzly" extra strong polyester sewing thread from my sewing kit …

… and threaded it through the 150 lb Dyneema line that I'd set up as the winch loop.

The rings were sewed and knotted on to the Dyneema line, and the knots etc. further secured with a few drops of thin CA glue.

I placed the rings to fit a 100% servo throw set-up, although in practice I think I will most likely use something along the lines of a 65% servo throw; this, however, is of course not a problem, as the loop travel will be correspondingly less than at 100%. In the image below, the rings sit at their 65% throw innermost points of travel, i.e. where they will be when the sails are fully sheeted home.

To be continued …

/Mattias

[BanjomanParticipant @banjoman]

Work on the new rudder continues to progress: once the plastic weld was fully set …

.. the aft edge of the blade could be filed and sanded …

… to a reasonably hydrofoil shape …

… after which any remaining space between blade and post was filled with Milliput …

… and the blade set aside for the Milliput to go off.

In the meantime, I planed, filed and sanded away the joint marks between the two hull halves along the keel line.

Once the Milliput on the rudder had set, the blade was checked again, its shape further refined and finally the blade surface polished with 400 and 600 grit dry followed by 1500 grit wet paper.

With the rudder blade and post thus finished, it was time to install it in the hull. The lower end was set into the skeg bearing, and a weight of lead shot taped to the blade to help keep it completely centered and well seated.

The new rudder tube was then inserted from above, and push fitted as far down as it would go under minimal finger force.

A small dollop of 24 hour epoxy was placed around the tube were it went down into its hole (taking great care not to drop any down the tube itself). A second length of 4 mm tubing was then slid onto the post and the rudder tube carefully knocked down by light blows from a small hammer …

… until the lower end of the tube sat just shy of the upper pivot.

The lower end of the tube was then seated in more Milliput, and the whole thing left for the various adhesives to go off.

To be continued ..

/Mattias

Edited By Banjoman on 20/07/2016 18:47:30

Edited By Banjoman on 20/07/2016 18:48:44

[BanjomanParticipant @banjoman]

While the epoxy and Milliput was going off, I turned my hand to making up the three sheets. For each, a thimble was set into the end of a wire hooksnap, one end of a length of 150lb Dyneema line (the same that I used for the winch loop) laid around the thimble, and the whole shebang set up under light tension in a fretsaw handle.

A piece of extra strong polyester sewing thread was then taken through both ends of the line, just at the thimble …

… and the line seized, using the method recommended by Harold A. Underhill in Vol. 2 of his excellent Plank-On-Frame Models and Scale Masting and Rigging.

The whole was then further secured by a few drops of thin CA glue, and the (in this case main) sheet hooked on to its ring on the winch loop.

The two foresail sheets were made up in the same way, and hooked into their ring …

… thereby completing the hull part of sail winch/sheeting installation.

To be continued …

/Mattias

Edited By Banjoman on 20/07/2016 21:37:27

[BanjomanParticipant @banjoman]

The last job tackled yesterday was getting the tiller back in place.

First up, some masking tape was wound around the rudder post were it comes out of the rudder tube, to hopefully at least help guard against any solder getting into the tube.

The tiller was then adjusted in relation to the servo arm …

.. the nuts tightened against the tiller …

… a heatsink attached to the post …

… and the whole shebang soldered together, to provide a working tiller …

… and once again give Moonbeam a functioning rudder!

To be continued …

/Mattias

Edited By Banjoman on 21/07/2016 08:11:33

Edited By Banjoman on 21/07/2016 08:12:21

[Dave_PParticipant @dave_p]

Really nice work Mattias. I am enjoying following your build.

[BanjomanParticipant @banjoman]

Thank you very much, Dave!

Since I reinstalled the tiller the other day, I have been thinking about whether the techniques used would be sufficiently strong or not. The (potential) problem with soldering threaded parts together when they're screwed onto the same thread is of course that that essentially makes them one big nut. In other words, the only thing that holds the tiller against the rudder post is the strength of the solder joint, and this is exactly what had me worried: should that joint break, the whole tiller unit, locking nuts and all,would no longer turn the post but just be screwed up and down along its thread.

To further aggravate my worries, I have good reason to believe that this particular solder joint is not the strongest one that was ever made, given that (a) it is soft soldered, and (b) the combination of the necessarily heavy duty heat sink and general fear of overheating things in case the plastic or GRP should be damaged meant the joint was made with as little heat as I could get away with/dared apply.

And finally, should the joint break after the deck has been installed, it would be very tricky to get a good enough access to repair it.

The conclusion from all this thinking was that I would have to complement the solder joint with a mechanical joint!

Said and done: I first drilled a 0.7 mm pilot hole at +/- 45 degrees through the tiller, the two adjoining nuts and the rudder post, using a pin vice rather than a rotary tool in order to avoid vibrations and aid precision.

This pilot hole was then enlarged to 1.2 mm, again with a drill bit in the pin vice …

… and a M1.2 nut-and-bolt put through the hole.

Finally, the nut-and-bolt assembly was secured in place with some more solder.

While a M1.2 brass bolt is not the strongest piece of metal on Earth, and on its own would probably have had me worried of mechanical failure rather than solder joint failure, taken together the two joints should be more than up to the job: the mechanical connection should stop the solder joint from breaking by making any movement impossible, however slight, that does not also bring the post along, thus relieving stress, while the solder should provide the main strength of the combined joints. Hopefully.

I also added a piece of elastic string to better secure the battery pack in its tray …

… and likewise secured the cotter pin that holds the winch hood in place.

With all this done, I double checked the instructions, but could not find that I'd missed anything that should go in the hull. It was thus time to put the lid on, i.e. to glue down the deck!

The technical installation was first protected with some cling film, after which the sheets were threaded through their respective holes in the deck, and 24 hour epoxy applied to all the joint areas.

The deck was then put in place, adjusted and taped and weighed down for the epoxy to go off …

… with the following end result.

As the picture shows, the fit of the deck to the hull is less than perfect, but this is not the biggest of deals, given that I plan to add a second, individually planked deck anyway.

To be continued …

/Mattias

Edited By Banjoman on 23/07/2016 08:14:55

Edited By Banjoman on 23/07/2016 08:15:29

Edited By Banjoman on 23/07/2016 08:15:43

Edited By Banjoman on 23/07/2016 08:16:04

Edited By Banjoman on 23/07/2016 08:18:20

[Dave_PParticipant @dave_p]

The pin idea seems a good idea as a locking device. Just wondered if you had thought of Loctite Retainer. It is a very strong industrial locking fluid but is not cheap. Easy for me as I have access to most of the Loctite products as they are used within my trade as diesel engineer. Thread lock would be fine but the retainer is far stronger.

[BanjomanParticipant @banjoman]

Dave,

Thanks for the suggestion! Yes, I did consider using some form of seriously strong thread locker, but in the end decided against it; not so much because of what it might cost, but because I have no experience of using such products and thus do not really have any feeling for what they can and cannot do.

The advantage compared with solder would of course have been that I would not have had to deal with the issue of making sure not to apply too much heat, and so in principle would have known for zartain shure that the joint was as strong as it could get. I would still have decided to pin the joint, too, though, so from that point of view it wouldn't have made any difference.

One of these days, though, I shall try to get hold of some, and carry out a few tests to get a proper idea of what it can do, so thanks again for the tip!

/Mattias

[BanjomanParticipant @banjoman]

With the first deck in place, and the epoxy fuilly gone off, it was time to start masking things off …

… until both the deck, the shroud plates and the upper part of the hull were all covered good and proper. It took a couple of hours to get there, but it is, I find, well worth the effort, as it seriously reduces the subsequent effort that has to go into sanding down the filler …

… which, as the below photo clearly shows, is absolutely required!

For this sort of filler job, I much prefer the classic that is Isopon P38, which, as I think we all know, doesn't 'alf pong! I therefore brought Moonbeam up from the workshop to our back balcony, and set her up on our potting table …

… and got stuck in. Given the comparatively short time one has to work this particular filler before it starts to set and becomes unworkable, I did the job in five short sessions over the afternoon …

… until the complete circumference of the joint between deck and hull had been dealt with.

This also shows why the masking job will pay off: all the extraneous filler inside of the masked-off line will simply be pulled away with the masking material, and only the bits that are really needed will be left to sand.

I dare say some further touching up may well become necessary, but generally speaking most of the excess will just be pulled away.

To be continued …

/Mattias

Edited By Banjoman on 23/07/2016 21:34:44

[BanjomanParticipant @banjoman]

The Isopon P38 took rather longer to go off completely than expected, and some on either side of the starboard shroud plates was still soft efter 48 hours and had to be removed. I suspect that, anxious to keep the workable time of the mix as long as possible, I may have been a tad too sparing with the hardener – and certainly with the batch that went around the starboard shroud plates!

Anyway, for the most part, it had set nicely this afternoon, and so the masking materials could be removed, and shaping started.

After planing off most of the excess, it was time to get out files and abrasive paper …

… at which stage a careful look confirmed what I had long suspected, namely that the stern curvature was not symmetrical between the two halves of the hull. It had looked like that to me all along, but with everything filled in solid it was obvious even at a glance that this would have to remedied.

I therefore traced the port curvature onto a piece of paper …

… transferred it to the starboard side …

.. again got the files out …

… and brought the stern down to a rather more symmetrical shape. There is still a certain amount of fairing up to be done, and some more filler shall be reuired here and there, but it is at least going in the right direction now.

To be continued …

/Mattias

Edited By Banjoman on 25/07/2016 19:30:32

[BanjomanParticipant @banjoman]

To replace the P38 filler that never went off, I decided to use Milliput instead, as the latter is easier to apply with precision …

… and (because of its long setting time and how it reacts to water) to smooth out and shape before it goes off.

Also, because it hardly gives off any smells or vapours at all, it can be worked indoors with no problem whatsoever.

Once set, it is just as easy to shape and sand as p38 for a nice, crisp edge and a smooth surface.

To be continued …

/Mattias

Edited By Banjoman on 28/07/2016 06:51:06

[Bob Abell 2Participant @bobabell2]

Hello Banjo

I`ve had a few sessions of non setting P38………It`s most annoying

One would have thought that a smear of Hardener would have corrected this…….But it doesn`t work for me!

I usually add too much hardener, these days, just to make sure………Then apply the filler at high speed before it goes off!

I wondered why you weren`t too bothered about the top deck mis-match……….Didn`t realise you would be replanking the deck, with all those fancy joints and nails!

Bob

[BanjomanParticipant @banjoman]

Hello Bob,

Annoying is indeed the word! One of the things I really like about Milliput is that is is a 50/50 mix of paste and hardener, so that even in small batches you can weigh it out on a set of scales for a consistently spot-on result.

That said, P38 is a really great filler with many, many uses, and I shall in the future adopt the same strategy as you, i.e. overegg a bit on the hardener, and work faster.

And yes: it is going to be an interesting exercise, replanking the deck, particularly when it comes to the joggled plank ends and the corresponding edge planking …. he said with some trepidation!

/Mattias

[Bob Abell 2Participant @bobabell2]

Unless you like punishing yourself……….I would ignore all that edge notching………Life`s too short!

Bob

[BanjomanParticipant @banjoman]

Oh, I don't kinow, Bob — although I'm certainly not into auto-S&M in any way, shape or form, I think it would be rather a pity to not at least give it a go … and, given the fairly regular geometry of the pattern, it should, I think be at least feasible?!

I am in any case planning to plank from the centre out, so we'll see once I get (close) to the edges …

/Mattias

Edited By Banjoman on 28/07/2016 12:22:13

[Ian GardnerParticipant @iangardner62867]

I agree Mattias. Having planked many decks myself you can easily lose the will to live but the end result is always worth it and it is, after all, one of the most visible aspects of a model boat. You will make a lovely job of it and we all wait with baited breath!

All the best,

Ian

[Bob Abell 2Participant @bobabell2]

Banjo

Got an idea!

Is feasible to simply smarten up the deck, with an ink pen……….As it was supplied in the kit?

Bob

[BanjomanParticipant @banjoman]

Bob,

Thanks for the suggestion — I guess it might just be possible, but not with a very good looking result. Also, I do not at all mind the upcoming planking work, but on the contrary look forward to it! Not to mention that I bought the necessary wood months ago.

Most important, though, is probably the fact that I don't really like the look of pre-printed decks: I find the lines too blurry and the whole aspect of it less than pleasing, which is why I had planned to go for new planking even before I'd bought the kit.

Ian,

Warmest thanks for your kind words of encouragement

/Mattias

[BanjomanParticipant @banjoman]

Before getting down to the brass tacks of actual planking, I first re-checked the symmetry of everything, and in particular the fore-and-aft centre line …

… against the width of the hull …

… both by measuring across in a number of places …

… and by dryfitting 50 planks …

… each one 5 mm wide, from midships and over the bows.

What I found was that, all along the central parts of the hull, everything is fine to within about half a millimeter or so, but that at the bows and in the stern, I shall have to deviate sligthly from the straight and narrow; at the bows, for instance, I would run into to symmetry problems if I were to plank in a straight extension of the midships centre line, so from the third hatch forward, I will let the planking go slightly to port, as can be seen in the below photo.

The fourth (and foremost) hatch will by the same token have to be enlarged to port by about 3 mm, and the hole for the jib sheet offset too.

All in all, I think that this deviation will be slight enough to fool the eye, unless one were to take a very careful sight along the deck, and I am in any case convinced that it will look much better than to have the edge planking and joggling visibly different to port and to starboard of the bows.

The same principle, but with a smaller deviation to starboard, will apply at the stern.

To be continued …

/Mattias

Edited By Banjoman on 31/07/2016 17:07:03

Edited By Banjoman on 31/07/2016 17:08:40

[Bob Abell 2Participant @bobabell2]

Hello Banjo

I admire your attention to detail

Bob

[BanjomanParticipant @banjoman]

Thank you ever so much, Bob!

Before planking proper could commence, I had one more (small but still) job to sort out, namely the final four deck beams!

These have no major impact on structural rigidty, but will mainly serve as linings of the fore and aft edges of the mid two hatches.

After filing and sanding them to fit, I masked off the top edge (which will take the glue joint) and covered the remainder with finsihing resin.

Once the resin had gone off, the beams were glued in place with 24 hour epoxy, first along the aftmost …

… and then along tehe foremost hatch edges.

While waiting for the epoxy to go off in its turn, I brought out my Rotatrim, and some black cartridge paper …

… and cut off a number of strips, +/- 1.5 mm wide, for upcoming caulking purposes.

To be continued …

/Mattias

Edited By Banjoman on 31/07/2016 18:38:54

Edited By Banjoman on 31/07/2016 18:39:33

Edited By Banjoman on 31/07/2016 18:40:37

[BanjomanParticipant @banjoman]

The first bits of real planking to do were of course those around which the main planking will have to be fitted, such as the mast base ring surround. To this end, a round piece of pearwood was cut from some 1 mm sheet with the help of a circle cutter …

… and finished off in the Dremel …

… to produce a blank of the correct shape and size.

On this blank was then pricked out …

… and drilled for the dowelling.

Next, the blank was quartered, and caulking strips glued on …

… after which it was glued in place.

Once the glue (for this job I'm using Deluxe Materials aliphatic resin) had gone off, the centre was opened up to a rough correspondence with the previously drilled mast hole underneath, and a caulking strip added to the circumference.

Apart from the mast foot surround, there are also three more circular surrounds for the deck sheet outlets. As making up the mast surround had involved a few failed attempts at cutting out the initial round, I now took three such rough rounds and set them up in the micro lathe …

… and turned them down …

… to the correct size (18 mm diameter) …

… drilled them for dowelling …

… quartered them and added caulking strips.

They were then glued in place (with the excess caulkiing strip glued on around the circumference) …

… and then opened up in the centre …

… to take the white metal sheet outlets.

The planking, caulking and dowelling will of course have to be sanded smooth, but that shall have to wait until the whole deck has been finished.

With the four circular surrounds sorted, I turned to the square hatch surrounds for which I made up a simple jig from styrene strip to facilitate pricking out the corner dowelling holes in a consistent manner.

Before it was time to call it a day, I made up and glued in place the aftmost hatch surround.

For this, I used the same 1×5 mm pearwood strip that I shall use for the main planking, while the dowelling effect is from 1 mm walnut dowel.

To be continued …

/Mattias

Edited By Banjoman on 01/08/2016 08:44:00

[Bob Abell 2Participant @bobabell2]

So the Plankathon begins!

A suitable starting point, Banjo

Tip for today……..A wire brush is good for removing fluffy edges

Bob

[BanjomanParticipant @banjoman]

It does indeed, Bob!

Many thaks, too, for the wire brush tip! I have indeed found on previous occasions that it is important to remove as much as possible of caulking strip edges, to avoid an excess of black paper dust when sanding, as it tends to get into the woodgrain.

/Mattias

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