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NRG Capstan Project by gjdale (Grant) - Scale 1:16 - Finished


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I am between modelling projects at the moment. Some time ago, I managed to acquire some additional stocks of very nice modelling timber from Jeff Hayes when he closed down his Hobbymill operation, so I decided that the Capstan model project from the NRG would be a good use for some of that stock and would give me a nice entry back into the scratch building side of things. Plans and instructions are by Toni Levine. As I have all of the toys, I decided to go straight for the Advanced version – hopefully, I won’t regret that decision down track!

 

I will be building at a scale of 1:16, as Toni did in her version.

 

I have downloaded all of the instructions and plans, ensuring that I had the amended version. The first challenge was to create a cutting list to determine the stock sizes I would need. As Toni has provided drawings with full size measurements in decimal inches, I decided that the easiest approach would be to create a spreadsheet to do all of the conversions for me. As my lathe and mill are both calibrated in metric units, I set up the spreadsheet to spit out measurements in both scale millimetres and scale inches (both decimal and fractional). I then went through all of Toni’s drawings and entered in the full size measurements and let the spreadsheet work it’s magic. While I was at it, I made a separate part of the spreadsheet a simple converter to use for other measurements as they crop up. This is proving to be a very useful tool, so I’ve attached it here in case anyone else might want to use it and save themselves from having to duplicate the effort. I take no responsibility for the accuracy of the information!!!

 

Capstan Parts Scale Converter.xlsx 

 

With that task completed, I then went through my stash of timbers and selected some pieces that were close to the right thickness and processed them through my full size drum sander until I had all stock material to the appropriate thickness. I’ll be using Pear for the Beams and Carlings, Red Heart for the Hatch Coaming, and Box for the majority of the rest. I may use Red Heart for the Capstan Bars also, but I’ll reserve a final decision on that until I reach that point.

 

Toni’s Practicum is very well laid out and not only identifies parts by part number but also groups these together into sub-assemblies. This is a really useful inclusion (thanks Toni 😊). Although the sub-assemblies can theoretically be completed in any order, I will follow along in the same order that Toni has used – I figure that way there is less chance for me to screw it up.

 

The Deck and Hatch collectively make up Assembly 100. This comprises sub-assemblies 101 (Grating), 102 (Hatch), 103 (Deck) and 104 (Capstan Step). We begin with the Deck.

Deck (P/N 103)

Although I will need to use metric measurements when it comes time to use the lathe and/or mill, for the most part it is more convenient to work in fractional inches, simply because of the way the scaling works out (eg 1/2" vs 12.7mm). My spreadsheet gives me the scale size to the nearest 1/16 inch (although I can check against the decimal inches (thousandths) if required. A glance at the spreadsheet tells me that the Beams are made from 1/2" stock and the Carlings from 9/32” stock. These were cut to final length and width on the Byrnes Saw. The Beams were then numbered and marked with a carpenter’s triangle to ensure correct alignment before being arranged in my magnetic holding jig for marking out. I first marked the centreline and then laid out the mortices from the centreline. 

 

558868374_001BeamLayout.jpeg.21223936dbb8026529c67aa47f5b512f.jpeg

 

Markings were made lightly in pencil to begin with, with the inner edges of the mortices being defined from the measurements in the drawings, and the outer edge defined by placing the actual Carling on the beam to get the exact width.

 

The marks were then transferred onto the vertical surfaces and a knife used to mark all cross-grain lines, while a marking gauge was used to mark all along-the-grain marks. This gave me some very well-defined layout lines. (I went over the cut lines in pencil just for greater visibility).

 

1557971842_002BeamMarking.jpeg.a00a389ed9b38e685e2356bae076e926.jpeg

 

The mortices sides were then cut using a razor saw (in much the same way as one would cut the sides of a half-blind dovetail) and the remaining waste removed slowly and carefully with a full sized very sharp 3/8” chisel. The tenons were cut on the Byrnes saw using the sliding cross-cut table and a stop to ensure that all tenons were exactly the same size. I had one very minor “oops” with the chisel – see if you can pick it. Here is the result:

 

150485901_003DeckComponents.jpeg.a910b9dc018992cc3630daac66878939.jpeg

 

Once satisfied with the fit, the pieces were glued up. I was reasonably happy with results.

 

1303961803_004DeckAssembled.jpeg.e05149def8199f1726408c31b0f80f6e.jpeg

 

I then made up a mixture of pear wood sawdust and diluted white glue and rubbed this over the joints and allowed it to dry overnight before giving it all a final sand with 240 grit today. As per Toni’s instructions, I also gave the underside edges of all Beams and Carlings a very slight round-over. Here is a shot of both the upper and under sides ready for the next step:

 

519714541_005DeckUpperSide.jpeg.b49a77762928ed2bea8eb249d1f52f4d.jpeg

 

1062290563_006DeckUnderside.jpeg.f5a684cc740673ccebc0adf24ec44b7f.jpeg

 

The Capstan Step will be next...

 

Edited by gjdale
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Capstan Step (P/N 104)

The Capstan Step is comprised of three pieces, joined by half-lap joints along the length of each piece. It is complicated slightly be the centre piece being thicker than the two outer pieces as it extends below the surface of the deck, between. I was puzzled by some of the drawings and instructions, until I realised that Toni had made this centre (thicker) pieces from two thinner pieces. As I had already milled some timber to the correct thickness to use a single piece for this, I went ahead and used that.

 

The half-lap joints were relatively easy to cut on the Byrnes saw. I attached a sacrificial fence that would allow me to partially bury the blade in the fence. Having set the blade height to exactly half the stock thickness (of the thinner pieces), I simply ran the pieces over the blade and edged the fence out slightly wider with each pass until the desired width was achieved. I used the micrometer stop to assist with the final passes to ensure that the exact width was obtained. One side of the centre piece needed the lap joint taking to a different height, but that was just a case of adjusting the blade height and leaving the remainder of the set-up in place.

 

The underside of the centre piece also needed to be notched at either end to fit between the deck beams. I used the same process for this, using the same set-up with a different blade height and fence setting. Again the micrometer stop was used to sneak up on the final cuts to ensure a snug fit between the deck beams.

 

Here is a shot of the fence arrangement:

 

1929123003_007SawSacrificalFence1.jpeg.51d4ab9f5f49351a6d10da164cc0f9ec.jpeg

 

And here is the centre piece after all joinery operations are completed:

 

719921297_008SawSacrificalFence2.jpeg.1d1428dfb0abe05868317aafd51b3a10.jpeg

 

In the above photo, I have also drilled the centre hole for the capstan spindle. I had to compromise here as the plans call for an 11/16” diameter hole and my drill sizes only included 5/8” or 3/4". I went with 5/8” and will adjust the size of the capstan spindle in due course.

The individual parts were then glued up, given a light sanding and the sharp edges and corners given a gentle round over.

 

733316135_009CompletedCapstanStep1.jpeg.96d9877462472f421dfb18048fc05a6b.jpeg

 

Here is a shot of the underside, showing the additional work on the centre section:

 

1662235793_010CompletedCapstanStep2.jpeg.db36612bad2749caca49cd380cd2c7bc.jpeg

 

And finally, here’s a couple of shots with the Capstan Step temporarily located on the Deck Beams:

 

770499390_011CapstanStepinDeck1.jpeg.1f132d1e377d632ab25966a9b5c06fdc.jpeg

 

1945769284_012CapstanStepinDeck2.jpeg.1110fea594bc830ac4fc911242eaf514.jpeg

 

I’m going to hold off on drilling the bolt holes for now. 

 

I think that all of the easy bits are now done. Next up is manufacturing the Step Brakes. I think I know how I’m going to approach that task…..

 

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Capstan Step Brakes

Although the Capstan Step Brakes form part of the Capstan Step sub-assembly, I’m treating them separately as we now venture into some metal work to fabricate these. These parts are an interesting example of where it is convenient to have scale conversions in both metric and imperial units.  Here is the drawing from the plans, with full size measurements in decimal inches:

 

289729788_CapstanStepBrakeDrawing.jpg.2d2a2f6348f91d947b6c5f9159ecf1ee.jpg

 

All of these measurements convert conveniently to scale fractional inches, which is great for initial stock sizing and layout. However, when it comes time to work the pieces in the mill, I need metric measurements.

 

First up, although Toni said she made hers from three separate pieces of brass silver soldered together, I decided to mill them from a single piece. The overall size of these parts dictate a stock size of 1/8” thick by 3/16” wide. I had some 1/8” brass flat-bar to hand, so the first job was to cut it down to size. To do this, I used double sided tape to fix the large piece to some sacrificial MDF and cross-cut it to a useable length using a slitting blade in the Byrnes saw with the sliding cross-cut table. I used multiple very light cuts until I was through the brass and into the MDF. I deliberately cut the piece twice as long as the finished size so that I would have plenty of “handle” when working the part. I then removed the cross-cut table and set the fence to the final width and used the same cutting technique to produce my starting stock.

 

Here’s the original piece of flat-bar stuck to the MDF and ready for initial cutting:

 

1117901537_013CapstanBrake1.jpeg.bc05f5fc7f033c3221d36ddf1adbf224.jpeg

 

And here’s the outcome of the saw table processes:

 

763648171_014CapstanBrake2.jpeg.b022491f417c9157d5aa56fa7ee96e34.jpeg

 

 

 

I then used some engineer’s marking fluid, a home made scribe, and some set-up blocks to layout the reference marks. This is where the imperial units were very handy.

 

1876029872_015CapstanBrake3.jpeg.d60edebd488e049361d9918a84bc7936.jpeg

 

I set up the mill with a 5/16” end mill cutter and cut the main parts. I set the vise in the rotary table for this so that I could also roughly shape the end to an octagon prior to final finishing (an idea I picked up from Tom’s (UsedToSail) log).

 

576689434_016CapstanBrake4.jpeg.45e591eeb78c74a21b103a27575583a0.jpeg

 

I then moved the milling vise to the tilting table and set the table at a 15-degree angle to mill the sloping section.

 

1361812294_017CapstanBrake5.jpeg.f6b7e3f671142b6cd73144f901191eb6.jpeg

 

The vise was then returned to the mill bed and the holes drilled in the end. The diagrams call for a 3/64” (scale) hole which equates to 1.2mm. However, I found that the 3/64” brass I had for the bolts would not go through this, so I opted to use a 1.3mm drill instead and this gives a nice sliding fit. The drilling was done using the Sensitive Drilling Attachment on the mill.

 

1420566749_018CapstanBrake6.jpeg.af68b404ed14590eda7491bdbcd57882.jpeg

 

Finally, the piece was reversed in the vise and the end mill cutter re-installed to cut the piece to final length.

 

772496197_019CapstanBrake7.jpeg.5ee9b98692aeac9ed63d5d5a79250ebd.jpeg

 

With all milling operations complete, the parts were then hand finished using files and sanding sticks. Here is the final result:

 

945440816_020CapstanBrake8.jpeg.f6593887e434422236d405118b35cdee.jpeg

 

Not perfect, but I’m happy with these. They will be chemically blackened in due course. On reflection, I could have done the milling sequences in more efficient order but then again, I had nothing better to do with my day….

 

Tomorrow’s challenge will be gratings…..

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Grating (P/N 101)

 Although Toni instructs us to make the Hatch Coaming prior to making the grating, I decided to make the grating first and then adjust the size of the Hatch if necessary. I have never scratch built a grating before, so this was to be new territory for me. Toni provides instructions for two methods of making the Ledges (the part with the “teeth”). I chose to follow neither, so what follows is my own take on how to make them.

 

The Battens (the part that fits into the “teeth” on the Ledges) work out at a scale 5/32” wide x 3/64” thick. This means that the rebate between the teeth, as well as the teeth themselves, must also be 5/32” if we are to achieve a square opening. Fortunately, I happen to have an end mill cutter of 5/32” diameter. Rather than cutting individual strips for the Ledges, then ganging them up to cut the rebates, then separating them again, I decided to cut the rebates into a single piece of stock that was wide enough for the individual Ledge strips to be ripped from later. The stock was also long enough for me to make enough for two sets of ledges.

 

Prior to cutting the Ledges, I did one test cut in some scrap and then used this as a gauge to fine tune the width of the Battens that were ripped on the Byrnes saw from some 3/64” thick stock.

 

The mill made short work of this task. By further happy coincidence, 5/32” converts to exactly 4.0mm, which made traversing the mill for each cut a lot easier. I am thankful to have the digital readout though – it made it much harder to stuff it up! I forgot to take some “in process” photos, but here is the result after milling (the rebates are 3/64” (1.2mm) deep).

 

969061155_21Gratings1.jpeg.6fffaa7a1a38e61ba63ac684db25d698.jpeg

 

The milling left a little fuzz on the edge of the slots, which was easily cleaned up with a swipe of some 320 grit sandpaper. Here is the cleaned up piece with a batten inserted as a test fit.

 

1711964367_22Gratings2.jpeg.003c31413a5ab54a1e03c2f41a0251ec.jpeg

 

 

This piece was then cross-cut into two sections, each with enough slots for a complete grating. The main reason for doing this was to shorten the length to be ripped as I find that the longer the rip cut, the more likely that binding on the saw blade will occur.

 

1956666768_23Gratings3.jpeg.0f95d3f1050620876e3080fef82af48d.jpeg

 

A piece of scrap was used to fine tune the fence setting, then the blocks were ripped into the individual ledge strips. There was sufficient width of stock to rip one spare Ledge from each block. Here are the final Ledges.

 

570093993_24Gratings4.jpeg.01c0f49f9faa917beb0b34af8149fb8a.jpeg

 

 

While I had the fence set, I ripped some 3.0mm stock to the same width to use as spacers while assembling the grating.

 

1511408999_25Gratings5.jpeg.9c23b4e803c0b86ab4629e6a9d96a74d.jpeg

 

Once I was happy with the dry fit, the Battens were removed one at a time, a drop of glue placed in the rebate and the Batten returned. Once I’d glued all of the Battens, the spacers were removed in case any glue squeeze-out accidentally caught them. 

 

1450513640_26Gratings6.jpeg.7accf860a6464ea41f745f2823196464.jpeg

 

Once the glue has set, I’ll trim the edges on all sides and add the (simulated) fastenings.

 

Next up, the Hatch Coaming...

 

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Two steps forward, one step back...

 

When I measured what would be the final dimensions of my grating, I was disappointed to find that it was significantly out from the drawings and Toni’s dimensions. I think this is a classic example of cumulative error creep. There are 7 Ledges and 8 Battens involved here, so a miniscule dimensional error in either of these soon adds up. I think that a rounding error in the scaling and or conversion to metric might also have been at play. The net result was that I broke out the isopropyl alcohol and disassembled the grating. 

 

I then printed out a scale version of the drawing so that I could overlay the grating on this as I was building it up. The spacing for the Battens seemed fine – meaning that my milling of the notches in the Ledges was okay. I found that by adjusting the spacing between the Ledges by the tiniest amount would result in final dimensions of the right size. After playing around a bit, I found that by using my set-up blocks with a 4.5mm combination gave just the right spacing. 

 

Here is the final result in place on the deck beams. If you look really closely, you can see that the holes in the gratings are not exactly square, but I’m satisfied with the overall appearance. I’ve yet to add the simulated fastenings. In the picture below, you can also see that I’ve drilled the bolt holes in the Capstan Step.

 

1195458569_26Gratings7.jpeg.428a3562e51d8c38ba01a9c7096988ee.jpeg

 

Now I’m ready to face the daunting prospect of the Hatch Coaming and it’s tricky angular joinery….

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  • 4 weeks later...

It seems that time has gotten away from me again! Thanks Bob and Tom for your kind comments and for all of the "likes". On with the show!

 

Hatch (P/N 102)

This is the trickiest part of the build to date. It is made so by the joinery for the hatch, with the Coamings and Head Ledges being joined by “tailed half-lap joints”. This means that the joints are angled in two planes. It took some time to get my head around these joints, and after a few failed attempts I had to walk away for a few days before trying again. Then I got distracted with other tasks around the house and suddenly it was a few weeks before I got back to it.

 

The key to success here is accurate marking out. To make the first half of the joint, measurements were taken from the drawings. I found my set of set-up blocks most useful for this task, along with a marking knife. The pencil was only used to go over the knife lines to improve their visibility. 

 

321233483_27HatchBuild_1.jpeg.cef7c931e615267f44238021d9953fa5.jpeg

 

1568744588_28HatchBuild_2.jpeg.94e3d0c386980d7aab2e46fd69a661d5.jpeg

 

The second half of the joint must be marked directly from the first half, and this is the most difficult part. The method I finally succeeded with was to mark a pin prick with the marking knife to correspond with all four extremities of the first half of the joint. Then it was a case of using a ruler and the knife to “join the dots”. Cutting the joints was achieved with a razor saw and a full size, very sharp chisel. By keeping away from the marked lines initially, I was then able to pare to the line with the chisel and make any minor adjustments for a good fit.

 

I got so engrossed in this process that I forgot to take any progress shots. Here is an example though of the joints cut, showing the angles in two planes. This picture is actaully of some “rejects”.

 

1376938842_29HatchBuild_3.jpeg.08e90c4b6e200a988bf7a44be560b6c1.jpeg

 

Once I had satisfactory joints in all four corners, they were glued up and the rabbet pieces cut to size and fitted.

 

The sides of the hatch are vertical for the bottom half, and then taper inwards by one-half inch (actual size). Rather than using a sanding block to achieve this, I used a marking gauge to define the extremities of the taper and then used a block plane to remove the excess material. I used my home-made mini Moxxon vise to hold the piece while I planed the sides, coming in from both ends to avoid breakout on the cross-grain joint.

 

496296918_30HatchBuild_4.jpeg.dc562cb1bd522d1b9f8b3ff2d2203750.jpeg

 

Here is the finished Hatch, ready for installation of the grating.

 

72220510_31HatchBuild_5.jpeg.f4d327594cfbf53b8459575d70b9a991.jpeg

 

The grating was then carefully adjusted for a snug fit. I found I needed to sand just the slightest amount off each side of the grating. It was then glued in place and the top surface sanded level with the hatch sides.

 

1914900817_32HatchBuild_6.jpeg.56412132ac9a633a4b9975644f103906.jpeg

 

  

I was contemplating how to mark out the positions for the fasteners, when it hit me that the answer was staring me in the face. I simply cut out the scale drawing of the grating and taped it over my grating. I then used my home-made needle point scribing tool to mark the positions.

 

1106911937_33HatchBuild_7.jpeg.321888f5c9b67d711036f4baa176ee93.jpeg

 

Once the pattern was removed, a pencil lead was twirled in the holes and the surface sanded lightly.

 

2093611044_38HatchBuild_8.jpeg.4434d067d00dc97df175da25f107dc9d.jpeg

 

And finally, here is an overview of progress to date:

 

2031424908_39HatchBuild_9.jpeg.3f15501c1ac9459f097312db14bda844.jpeg

 

That completes all the “easy” part of this build. Next up we commence some lathe work with building of the Capstan body.

 

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Thanks Bob,

 

It’s more difficult to describe than to do. Once you can visualise the completed joint and keep that straight in your head, marking the joint extremities on the second half of the joint is just a matter of being slow and methodical, and triple checking everything before cutting. If the marking out is correct, the joint will be a pretty good fit straight off the cut/pare. If the marking out isn’t accurate, you can end up chasing your tail for quite some time trying to get a good fit. In another log, Druxey suggested practising this joint on some scrap wood first. Good advice - my scrap wood just happened to be additional actual stock…….😉

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  • 2 weeks later...

After a brief side project making some bandsawn Reindeer Christmas decorations, 

 

349711325_Reindeer2.jpeg.38d69f49255076f71c2a97197f71bbca.jpeg

 

it was time to proceed with the Capstan Body. 

 

The Capstan Body is assembly P/N 300 and is comprised of the Barrel (P/N 301), the Whelps (P/N 029), the Chocks (P/N 030 and 031), and the retaining pin assembly (P/N 303).

Barrel (P/N 301)

The barrel, while made from a single piece of timber, has a varying cross section. At the top it is square, the mid-portion is ten-sided, and the lower part is circular, with a stepped section for the gasket. The retaining pin assembly is also cut from the same piece of stock. All of these cross-sections are achieved using a combination of the lathe and the mill.

 

It all starts with a square blank. The length of the blank needs to be long enough for a little extra length for work holding, but short enough that it will fit in the mill mounting arrangement (seen later).

 

Rather than mounting the (not-quite) square blank in a four-jaw chuck and leaving the extra length square-ish in section, I opted to mount it between centres and turn the entire length, which would subsequently allow me to mount it in a three-jaw chuck. Here is the start of the process.

 

709498270_40Barrel_1.jpeg.795482caf4782224fb8e55bd9595e58d.jpeg

 

Once the entire length was turned down to the maximum diameter of the barrel, the narrower sections for the gasket and the part that will go through the Capstan Step were turned down.

 

2084128071_41Barrel_2.jpeg.a1ceb19d2e611bc0f1a64d93f6ba7706.jpeg

 

The part was then removed from the lathe and inserted in a three-jaw chuck, which was mounted on the mill rotary table, which was attached to a right-angle mount. The “tail” end was supported using an adjustable tailstock holder. Here is the overall set-up, which facilitated milling of the ten-sided section and the square top section. In this photo all of the milling has been completed.

 

975360786_42Barrel_3.jpeg.b3567cc49088826182fedc8bcd264d41.jpeg

 

All of that sounds easy, and it is if you pay attention to correct set-up of your mill – which I failed to do on the first attempt. It had been quite a while since I had used the mill and I simply forgot some of the basics. After a failed first attempt, I started over and this time spent the necessary time to align the rotary table in both the Y and Z axes, and to align the tail-stock holder properly with the chuck. A little bit of fiddling to be sure, but really the only way to ensure that your final product will be what you intended, within the tolerances you intended.

 

The part was left in the chuck and the chuck removed from the rotary table and returned to the lathe for the next operation. After using a 1/8” centre drill to start the hole, a regular 1/8” drill bit was used to drill through the excess material, through what would become the retaining pin assembly, and into the base of the capstan body. This departs slightly from Toni’s drawing and is a little bit of a “cheat”, but was the easiest way to ensure that the holes for the retaining pin aligned perfectly.

 

1998548783_43Barrel_4.jpeg.8327cdcbcd16c638d0b1e584a064f393.jpeg

 

The main body was then separated from the retaining pin assembly and cut roughly to length at the top (square) end. The main body was then reversed in the chuck and the square end cut down to final length by a series of facing cuts on the lathe. Similarly, the retaining piece was cut to rough length with a hand saw and then re-inserted in the chuck and trimmed to final length with another series of facing cuts. After test-fitting the assembly, I found that the retaining piece needed to be significantly shorter than shown in the drawings in order that it not extend below the deck beams. This was a simple fix – the piece was marked to a new final length directly from the deck beams and re-inserted in the lathe for another series of facing cuts.

 

A piece of 1/8” diameter brass rod was cut to length for the retaining pin (P/N 028) and epoxied into the retaining piece (P/N 027). Here is a picture of all three pieces prior to gluing the retaining pin in place.

 

1676295842_44Barrel_5.jpeg.15c1f9f7f2b01ae8a9406f772773348d.jpeg

 

The Whelps are next….

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  • 2 weeks later...

Thanks for the kind comments Ben and Rusty, and for all of the likes. Life seems to have gotten in the way lately, so progress has been slow.

The Whelps (P/N 029)

Five Whelps are required and the particular challenge in making these is that they are tapered both top to bottom and rear to front. The first step was to cut some blanks and then glue them up into a sandwich with the basic profile outline on one face.

 

1187811182_45Whelps1.jpeg.0b82c4b89b8ba3fca9ce0a8cb0f4b224.jpeg

 

Toni’s advice in the instructions was to make a couple of spares, so initially I glued up a set of seven blanks. Unfortunately, when it came to milling the sandwich, I found that it was too wide for the mill travel, so I had to unglue them and re-glue with just five in the sandwich.

The basic profile was then cut on the mill by angling the milling head as shown by Toni in the instructions. Here is my set-up halfway through the milling process:

 

380838792_46Whelps2.jpeg.e27b58e68451354f9fd893a563728b25.jpeg

 

And here is the end result. Note that the blanks were left slightly long to allow for any chip-out during milling.

 

327271799_47Whelps3.jpeg.36c6969d4c45e689e323f3e11e07a587.jpeg

 

The blank was then taken to the Byrnes saw and trimmed to length prior to soaking in an IPA bath to separate the individual pieces.

 

Once separated, holes were drilled for the bolts and the individual pieces carefully marked out for the tapers. The top to bottom taper was tackled first, and is relatively simple to achieve using the Byrnes disc sander to freehand sand to the marked lines. The rear to front taper was a little trickier. After carefully marking out, the angle was measured using a protractor and the tilting table of the Byrnes sander set to this angle. With a little care, the correct taper was achieved. Here are the pieces after all tapers had been cut/sanded.

 

1623556591_48Whelps4.jpeg.23ec78ffee18dd5e6e4ec411875f7f0e.jpeg

 

The next challenge was to cut the notches for the Chocks. Like many things in woodworking (or metal working for that matter), the hardest part of the process is working out how to hold the work securely for the operation at hand. Having carefully marked out each piece for the notches, I found that my home-made Moxxon style vise was able to cope with the tapers quite well to hold the work.

 

672988700_49Whelps5.jpeg.1b204584638953cf68dcab2b3ca20b03.jpeg

 

I then used a miniature square and a marking knife to score the vertical cut line. This then provided a handy registration for the razor saw to make the vertical cut.

 

2009067040_50Whelps6.jpeg.bc5ecff97f9321461d8832ab9d42b89a.jpeg

 

A freshly sharpened full sized chisel was then used to pare the angled cuts.

 

1127187505_51Whelps7.jpeg.bedad2964de75ba227925305ecf13b4c.jpeg

 

 

Having worked out how to hold the pieces, the actual cutting of the notches went quite quickly. Here are the completed Whelps.

 

1048219169_52Whelps8.jpeg.db0a2c25799e2fa8e797518c85d8b139.jpeg

 

The Chocks will be next but will probably have to wait a day or two until after the fat man in the red suit has been.

 

 

Edited by gjdale
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  • 2 weeks later...
Posted (edited)

After some minor distractions over the Christmas/New Year week, the build continues.

The Chocks (P/N 030 and 031)

There are two sizes of chocks, with the lower one being thicker than the upper, and the angles of insertion being slightly different. They are essentially a wedge shape when viewed from above, but their sides are also tapered to match the notches cut into the whelps. To simplify construction, I drew up a plan for each in CAD using the dimensions from Toni’s drawings and then duplicated each of these to provide a strip of five templates for each of the upper and lower chocks.

 

The templates were printed onto sticky label paper and attached to the relevant stock size. The stock was then taken to the Byrnes saw and ripped to a width that would leave plenty of extra length on the chocks for fitting, and then the individual chocks were cross-cut using the angled mitre gauge.

 

The Byrnes disc sander was then used with the table tilted to an appropriate angle (about 30-deg) to trim the sides to a loose fit. The table was then returned to its 90-deg setting and the inner ends slowly sanded away until the chock was a tight fit. Each chock was marked with its location and the barrel also marked accordingly. The chocks were then glued in their respective locations and left overnight. Once dry, the excess material was removed firstly at the Byrnes disc sander and then with files and sandpaper to achieve the final shape. The concave face on the lower chocks was achieved by firstly making a rough shape using the oscillating spindle sander, and then refining with a contoured sanding block.

 

Finally, the whole assembly was remounted in the 3-jaw chuck on the rotary table on the mill and the bolt holes were drilled in the chocks. I opted to drill these at 0.7mm diameter to accept some 40lb monofilament for the bolts. This is somewhat thinner than specified but looks about right to my eye. 

 

I got so focused on the process, that I forgot to take any progress pictures. Here is the completed Capstan Body.

 

616523596_52Chocks.jpeg.f78381505ff4dc5e5cb3ec97e99d8a6a.jpeg

 

Next up, the part I’ve been dreading – the Drum Head Assembly….

 

Edited by gjdale
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The Drumhead Assembly (P/N 200)

 From the instructions, the drumhead is made up of six major pieces: two upper and two lower drumhead halves, an iron ring and the cap, along with several miscellaneous bolts and fittings. I decided that I would make each drumhead as a single piece rather than two halves glued together.

Upper and Lower Drumheads (P/N 18 & 19)

Toni’s instructions indicate that the Drumheads are each made up of two semicircular pieces of wood cut with a jeweller’s or scroll saw and glued together. I’m not sure why Toni took this approach, but assume it was because she didn’t have stock of sufficient width to cut them from one piece. If you’re reading this Toni, you may care to comment.  As I had some stock that was wide enough, I decided to make each of these as single pieces.

 

Toni then goes on to describe the milling process by gluing the two halves together temporarily, and then gluing these to a scrap of wood that is used to hold the parts in the vice on the mill. I was concerned about accurately centering the held parts on the mill, particularly with the amount of de-bonding, re-gluing and re-mounting to the mill.

 

I thought long and hard about this and have come up with my own solution to the problem. It may not be the best solution, but we’ll see whether it is successful…

 

To address the centering issue, I thought this would be much easier to achieve if the parts were mounted in a lathe chuck mounted on the rotary table on the mill. That meant that the scrap wood block holding the parts would need to be cyclindrical and held in the 3-jaw chuck instead of square held in the 4-jaw chuck. I don’t own an independent 4-jaw chuck and have more confidence in repeatability from the 3-jaw chuck.

 

The next consideration was how to easily register the center of the work on the mill, and also with each other when re-gluing. As the lower drumhead will have a large-ish square hole milled in it eventually, and the upper drumhead will receive a cap, I decided that if I drilled a 1/8 hole through all the parts, this would solve both of these problems. So far, so good – in theory…

 

Off I went then. I found a nice block of cherry in my scrap pile and cut this down to rough square on the big table saw. I then found the centre and marked a circle of about the size I thought looked good for a holding piece. I cut close to this line on the bandsaw and then mounted it between centres on the lathe and turned it to final diameter – a relatively quick exercise. I faced the ends square and this part was ready to go.

 

I then cut the two blanks for the drumheads from 1/4" Box sheet on the Byrnes saw. I made these as close to square as I could get. I marked the centres and drew a circle on each as a guide to the final diameter. I then spot glued these together. Once these were dry, I carefully spot-glued these to my holding cylinder, and once it was dry I went back to the bandsaw to rough cut the drumhead circle. My plan was to then return the glued up assembly to the lathe and turn down the final diameter of the drumhead. 

 

Here is the assembly on the lathe:

 

906238751_53Drumhead1.jpeg.7f361a0a68ad50f0438a61851534dee7.jpeg

 

It was about now that I realised that the diameter of the drumhead was too large for the lathe – doh!

 

While I had it all set up on the lathe, I centre-drilled a 1/8” diameter hole, then followed up with a regular 1/8” drill bit and drilled all the way through all of the pieces, and finally followed up with a 1/8” reamer. The purpose of this was to allow me to use a 1/8” rod to align the pieces when de-bonding/re-gluing, and also as a registration when mounting on the mill.

 

Speaking of the mill, as I could not turn my final diameter on the lathe, I transferred the assembly to the rotary table on the mill and used a 1/8” end mill registered in my locating hole to centre the work on the mill. I was then able to use this set-up to complete turning the final diameter on the drumheads by offsetting the cutter to the required radius (gotta love the digital read out for this job!). Here is the set-up just before commencement of milling.

 

1923437013_54Drumhead2.jpeg.0afbe7ca7e8a9657fbf2560eb84df2eb.jpeg

 

The milling went well, and I was then ready to cut the rebate for the iron ring. Calculating the width of this from the drawings worked out at 9/64”. My choice of end mills does not include a 9/64” bit, so I had a choice of either 1/8” (8/64) or 5/32” (10/64). After some deliberation, I opted for the larger size on the basis that it might make subsequent fabrication of the “iron” ring easier (perhaps slightly less prone to breakage if made from wood).

 

That process went well – very similar to turning the final diameter, only a different offset and cutting to a final depth of 0.5mm (slightly deeper than the 0.4mm (1/64”) called for in the drawings). I forgot to take a picture at this stage as I had just received a weather alert for thunderstorms and large hail stones – I had to cease play and put all the tools away so that I could get the cars in the garage before the hail arrived.

 

The parts are now soaking in an isopropyl alcohol bath prior to separating and regluing to mill the rebate in the other drumhead.

 

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"Toni’s instructions indicate that the Drumheads are each made up of two semicircular pieces of wood cut with a jeweller’s or scroll saw and glued together. I’m not sure why Toni took this approach, but assume it was because she didn’t have stock of sufficient width to cut them from one piece."  Sorry for the late reply.  The reason I used two pieces is that it how the actual capstan would have been constructed.  Consider for a moment how many oak trees 34" in diameter there are versus 17" in diameter.

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Posted (edited)

After separating the two halves of the drumhead, they were individually re-mounted to the holding cylinder to have the rebate for the iron ring milled. Each was then de-bonded, flipped, re-glued to the holder and the slots for the capstan bars milled. The drawings show these as 3.25” wide by half that in depth. At scale, that translates to 13/64”. Again, my choice of end mills was limited, so I opted to go with 3/16” (12/64”).

 

Here is a shot of the milling set-up after completing the capstan bar slots, but before cleaning up the “fuzz”.

 

137879750_55Drumhead3.jpeg.87c6fb6ef820e6651babf425c43725a5.jpeg 

 

Once both halves had been milled and cleaned up, they were temporarily glued together for the next milling process. Again, my alignment strategy paid off. Here is the drumhead mounted back on the mill – in this shot you can see the rebate for the iron ring milled in the previous process.

 

2006095338_56Drumhead4.jpeg.099ea44f3bb922d994432cd992e0c0b2.jpeg

 

To mill the rebate in the sides, the mill head was rotated 90-degrees to the horizontal position. It may just be me, but I couldn’t identify from the drawings what the depth of this rebate should be, so I just went with what looked “about right”.

 

1374205588_57Drumhead5.jpeg.e93d87295cde834b9a42f244c2b59a55.jpeg

Iron Rings (P/N 020)

The next task was to make the iron rings. There are two of these required – one each for the upper and lower drumhead. I thought long and hard about whether to use brass or wood for these parts, as well as a process by which to make them. In the end, I opted to go with wood as I had some pieces of ebony that I thought would fit the bill.

 

I began by milling the rough stock to a 6mm thickness. I chose this thickness as I was concerned about very thin pieces self-destructing in the fabrication processes to follow. I then placed blue painters’ tape on one surface and drew two concentric circles to represent the inner and outer edges of the iron rings. Happily, the diameter of the inner circle was 1 5/8”, which just happened to coincide with one of my Forstner drill bits. The centre hole was therefore drilled first, and then the outer diameter was cut to rough shape on the band saw and refined slightly at the disc sander. However, to get the degree of accuracy required, it was necessary to find a way to mount the part on the mill. To achieve this, I took a scrap of thick dowel (actually an old rolling pin), mounted it in the lathe chuck in the mill, and gradually reduced a section at the top until I was able to fit the ring part over it with a snug “push” fit. By having such a snug fit, I was able to complete the milling without having to glue the work piece to the dowel. I gradually reduced the outer diameter with very light cuts (0.1mm at a time) until the part would fit into the pre-milled rebate in the drumhead. Here is a picture of that process under way.

 

1779787313_58Drumhead6.jpeg.8527eb1fd8939b82b7311269d8ec2bba.jpeg

 

A slitting saw was then mounted in the mill and again using light cuts and the rotary table, I was able to cut the 6mm thick piece into two 2.5mm thick rings (I used a 1mm thick slitting saw for stability).

 

Here is a shot of this part of the process underway:

 

1834231567_59Drumhead7.jpeg.a131198a5c570da05b1af284bd15f8d9.jpeg

 

And at the end of the process:

 

 961377302_60Drumhead8.jpeg.588d08e83f96d0786c27e66263d34ddc.jpeg

 

Here is a shot of the rings test fit into the drumheads:

 

1284238516_61Drumhead9.jpeg.63bd50da396cbb2e44fe0ccdca9da817.jpeg

 

 

And a test fit with some spacer bars and the Cap (P/N 021) temporarily in place.

 

686517038_62Drumhead10.jpeg.f9b4302ca0122b3f41de9f7149be3b7c.jpeg

 

And here are the drumheads after sanding the iron rings flush:

 

1364761094_63Drumhead11.jpeg.db03c69fe96524004c17134049f9aa5b.jpeg

 

 

And finally, here is the overall state of play to date. No finish has been applied yet.

 

903773764_70Overview.jpeg.ef0f8e83228e0b914c3f2dcee0741a01.jpeg

 

Some metal work and the capstan bars are all that remain…

Edited by gjdale
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Capstan Bars (P/N 034)

The Capstan Bars are relatively simple to make. I am using Red Heart for these (the same timber as used for the hatch coaming). After cutting the blanks to size and finessing with the Byrnes drum sander to ensure all pieces were the same thickness all round, the tenons were cut on the mill and while I was at the mill, drilled the holes for the swifters.

 

I tested some options for cutting the tapers, including a full-size edge sander (not enough control), the tapering jig for the Byrnes saw (could only do two adjacent edges, and even then, the length of the pieces made this very awkward and a little dangerous for my liking). In the end I settled on my Proxxon belt sander. I bought this tool quite a few years ago and have never used it very much at all. It turned out to be ideal for this particular job.

 

1606695972_71CapstanBars1.jpeg.9ce5417d6c95a5495bf245e2592ce44b.jpeg

 

It had the added bonus of being able to be hooked up to a vacuum hose, so I brought my Festool shopvac inside (while the Admiral wasn’t looking) and made quick work of the tapers.

 

2035619524_72CapstanBars2.jpeg.d45bc909ffba87875f0f943d0a4154a1.jpeg

 

Final rounding and smoothing was accomplished with a combination of a modellers’ rasp, a soft sanding block, and a sanding sponge – no pics of this stage.

 

All of the parts have now been given a first coat of oil. All that remains now is to blacken and then install the hardware. Final pics once that has been done.

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Metal work and Blackening

I decided to “cheat” when it came to the bolts and have used two different sizes of brass nails left over from kits various to represent all of the bolt heads. Similarly, left over eye bolts were used for the bar retaining pins, and I found some chain sculling around in the spare parts box as well. The only thing I did make were the eyebolts that secure the bar pin chains to the centre of the drumhead.

 

There have been many discussions on this forum regarding blackening and I have tried various of them over the years. For blackening brass, my go-to product has become Jax Pewter Black, which claims to work with pewter, lead, brass, bronze, copper, tin-lead alloys, and solders. The key to success with this product (for me) has been to NOT dip or soak the parts to be blackened in the solution. Rather, by using a small bristle paint brush, the solution is “rubbed” onto the surface of the part, and then rinsed in distilled water. By using this method, I have found that the blackening does not flake or rub off. Here are all of the metal parts blackened and ready for installation. For the nails/bolts, only the heads needed blackening as the rest won’t be seen.

 

1095995728_73Metalwork.jpeg.ee6e2aff22c849e83bbd9fc079f3be17.jpeg

 

Final Assembly (P/N 1000)

All of the wooden parts received two coats of Kunos Oil, wiped on and buffed off immediately. This has left a smooth to the touch finish without too much sheen (more coats = more sheen). With all the metal work blackened, final assembly was a pretty straight forward process. I opted to use 5-min epoxy to secure all of the bolts etc, rather than CA (which I really hate using).

 

So here are some final shots of the completed project:

 

1875357727_74Final1.jpeg.329eb1009c28db1ca0ad50b9327ab55e.jpeg

 

428310412_75Final2.jpeg.44713026f7bee5c1510818293869e993.jpeg

 

477743311_76Final3.jpeg.e119c2e7ea55d5d5953883a9aed28a5d.jpeg

 

1914273327_77Final4.jpeg.dd8608766f5e32acca1a3cd6c1680f21.jpeg

 

1262451081_78Final5.jpeg.7b25fa3d8769cd03cf515112e67ea9c2.jpeg

 

 

This has been a fun little project that presents more than a few challenges for modellers of all capabilities. I’d like to thank Toni for all her work in making this project available. I'd also like to make a special thanks to Tom (Used to Sail), whose log was a great source of additional information, as well for the occasional PM conversation along the way. Thanks also to all who have stopped by, offered kind comments and/or hit the like button.

 

Edited by gjdale
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  • The title was changed to NRG Capstan Project by gjdale (Grant) - Scale 1:16 - Finished

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