NRG Capstan Project

[Justin P.]

47 minutes ago, kurtvd19 said:

This isn't the type of project where templates are needed.   Every dimension of each part is provided in full size so marking the parts in any scale the builder picks is able to be accomplished with more precision than printing out the plans to use as a template.

Thanks Kurt, I can understand the thinking here.   I was really more curious about the choice to depict different parts in different scales in the plan sheets, and if there is a reason for this, or if its more an arbitrary choice. 

 

For anyone working with the same brain disadvantage as I am,  I found that printing the plans at 100% on regular 81/2 x 11 paper gave a precise representation of 1:16 components.   I then went back and printed the 1:1 plans separately at 75% and the resulting print was scaled to 1:16 accurately.   Ive gone through and checked my printed sheets against my manual calculations and everything checks out.    Of course its important to know your printer before relying on this for precise representation so double check everything against manual calculations for dimensions running in both directions.    

 

I know this stuff is probably automatic to most of you, but when numbers and language don't match my brain starts misfiring.  For instance, 3/4 scale being represented as 1:16 but needing to be printed at 100% gets a bit confusing to me 😀.     I feel like I can read all day about it and still not fully understand...    thankfully my 7 year old gets it (and printers).  

[kurtvd19]

Justin:

Parts are often drawn at different scales for clarity.  Some smaller parts if drawn at 1:16 would be tiny on the drawing so they are drawn at a larger scale so details can be easily seen.  Many drawings will show objects at different scales on the same sheet for this reason. 

 

 

[Justin P.]

4 hours ago, kurtvd19 said:

Justin:

Parts are often drawn at different scales for clarity. 

I figured this might be the case, the difference in these plans is negligible so wondered if there was some other reason.  Thanks.  

 

 

Edited May 21, 2021 by Justin P.

[tlevine]

Kurt is right in the reason for the different scale.  In putting the plan set together, I choose the largest scale that would fit on standard printer paper.  The occasional 1:1 drawings are for clarity.  The best advise is to choose your scale and then derive a table of dimensions for that scale.  Build from the dimensions, not from the drawings per se.  The one part for which a template comes in handy is the whelp.

[tlevine]

The advanced capstan project assumes the builder has access to a lathe and mill in addition to a hobby-size table saw.  A lot of the steps are similar or identical to the intermediate project and will not be repeated.  

 

The deck beams and carlings are made first.  Unlike the intermediate version, "proper" mortice and tenon construction was used.  My preference is using a chisel to make these but they can also be done on a mill.  The end result will look identical to the intermediate version.

The capstan step is comprised of three planks with half-lapped joints.  The center plank is thicker and inserts between the beams.  I added this as a separate piece.

This shows the step glued up, the hole for the barrel and various bolt holes have been drilled.  I would recommend not drilling the bolt holes until later in the build, as described in the monograph.  All sharp edges have been rounded off.

 

 

 

 

[Tim Murphy]

Sorry, To say the only piece of equipment that I have is  Byrnes saw. No drill press or milling machine. The saw was expensive enough.

[tlevine]

The intermediate capstan project only requires the saw.  The only other powered tool I used was a Dremel to make that.

[tlevine]

The step has been temporarily installed onto the deck.  You can see the half-lapped joint in the red circle. 

The hatch is next.  In contrast to the intermediate version, the head ledges and coamings are joined with a locking half-lap joint.  This prevents the corners from pulling away from each other.  I could not find any easy way of making the joints.  The best advise that I can give is to make everything oversized and, once you are happy with the joints, sand the pieces down to their final height and length.  

After the hatch has been assembled, glue in the rabbet (hopefully doing a better job than I did).  The sides of the hatch are vertical for the lower four inches. Above that, as shown by the red line, the outside surface tapers inward by one-half inch.  I used a sanding block to obtain the final shape.  Chamfer the top edges and the corners down to the level of the deck.  Grating was discussed in the intermediate version. 

[tlevine]

Trial fit the hatch and capstan step onto the deck assembly.

[druxey]

I might suggest making a coaming joint from scrap first as practice and to provide a pattern for the actual joints.

[tlevine]

Excellent suggestion, Druxey.

[tlevine]

The barrel is made up from four smaller pieces of wood because at the scale at which I am building (1:16), a piece of wood 7/8 inch sq. would have been required.  I started by chucking it up in the lathe and turning it down to the maximum diameter of 13 inches.  Once that was done, I drew lines to note the changes in diameter.  In the first picture you can see extra length at both ends of the blank.  In the second one, the extra length is only at the chuck, not the live center.  I discarded that part because I discovered that I could not mill the piece without support on both ends.

I started at the bottom of the spindle.  You can see the 11.25 and 13 inch sections have been completed and I am working on the 11 inch section.  The 11.25 inch section will be a gasket, preventing the whelps from rubbing against the capstan step.  After all, we want this capstan to be able to turn when completed.

The spindle was removed from the lathe and mounted on the mill.  I kept the spindle in the four-jaw chuck and screwed the chuck into the rotary table.  I had to Rube-Goldberg the other end for support and to keep it level.  In this case, the live center is held in the mill vise.  This was raised above the bed as required.  It was easy enough to hold the vise in one hand while moving the bed with the other.  Once one face was completed, the table was turned 18 degrees and the next face was milled until completed.  Next, the square head was milled and the piece was removed.  The supporting wood was cut off both ends and the lower thirteen inch section was removed with a razor saw.  This piece will become the retaining pin to secure the barrel to the step.

[tlevine]

There are five whelps.  Their sides flare out top to bottom and from the spindle outwards. The outer face is cut first and then sides are tapered.  I made a sandwich of the five whelp blanks (and a few extras) and drew the outer face of the whelp onto the sandwich.  There is a little extra wood at the top and bottom to compensate for any chipping from the mill.

The outer face was milled in three steps, rotating the mill head to obtain the correct angle.  The key is to only remove a little wood with each pass.

The sandwich is separated into individual whelps by soaking it in isopropanol.  The taper was formed on the disc sander and the bolt holes were drilled.

The final step was to cut the slots for the chocks.  I used a razor saw and chisels to form them.

[tlevine]

Two thickness of chocks are required; the lower ones are thicker.  Glue the whelps onto the spindle and then install the chocks.  You can see the concave curve of the lower chocks and the convex curve of the upper.

 

[tlevine]

The barrel is complete except for bolts in the whelps and chocks.  Just like in the intermediate project, the drumhead is made up of seven major pieces, two upper and two lower drumhead halves, two iron rings and the cap.  There are also several miscellaneous bolts and fittings.  After the two drumhead halves have been glued up and shaped (see the posts in the intermediate project), they are each glued to a block of wood.  This block of wood secures the drumhead to the mill vice so that the recess for the iron ring can be milled. Do this on both the upper and lower drumhead parts.

Debond the block of wood and glue it onto the other side of the drumhead to mill the slots for the capstan bars.  The lower drumhead has a square opening for the top of the barrel.

The iron ring is next.  I made mine from contrasting wood, in this case pear.  They are difficult to cut out without breaking because they are very thin and require cutting across the grain.  I cut mine with a jeweler's saw.  I made the rings thicker than necessary and sanded them flush to the drumhead.  The cap was 

A block of wood was inserted through the square opening in the drumhead bottom.  This was then clamped into the mill vise and the side recess was milled.  I started in the middle and slowly worked my way out to prevent tear-out.  The last bit was finished by hand with files and an 11 blade for the same reason.  Finally the cap was glued in place.

 

[tlevine]

An alternate approach would be to use brass instead of wood to represent the iron ring.  The bolts are brass nails with their heads filed flat.  The holes for the capstan bar pins have been drilled.

After a coat of finish, the capstan is trial fit on the step.  Compare the appearance of the step and capstan in the next two pictures, showing the effect of a coat of Watco's.  I used copper wire for the whelp bolts and they have not been blackened yet.  This will be done with liver of sulfur.

The eyebolts  and capstan bar pins have been installed.  Make sure the chain is long enough to allow removal of the pin.

 

 

[tlevine]

All that is left to make is the capstan bars and brakes.  This was shown in the intermediate version and will not be repeated.

Time to put everything together.  This was a fun project to design and build.  It does not take a long time to build and it makes a handsome desk ornament without the bars or in a display case with the bars installed.  The project is available for purchase in the NRG store at https://thenrgstore.org/collections/plans-and-projects/products/capstan-project.  It contains separate plans and monographs for the intermediate and advanced versions.  

 

[usedtosail]

Since I am between ship models and I am interested in scratch building in the future and the weather has been very rainy this Summer, I decided to try to build this capstan model. I have the tools so I am going to try the advanced version. I am in the process of getting the wood together. I can start a build log for this if people are interested.

[kurtvd19]

Absolutely.  

[Cathead]

Yes, please do, this is one of my next projects and I'd enjoy reading some third-party experiences.

[usedtosail]

I have started a build log here: https://modelshipworld.com/topic/29396-nrg-capstan-project-by-usedtosail-116/

 

[tlevine]

Please and thank you.

[Gregory]

On 6/11/2021 at 9:49 AM, tlevine said:

All that is left to make is the capstan bars and brakes.

Looking for an opinion..

 

Chuck had posted a picture of this contemporary model in another topic..

 

I had asked about the eyebolts but no one responded.

There are only two, and they look a little heavy for the bar retention pins as shown on your model.

After seeing your model, I thought maybe they might put several pins on one eyebolt.

 

Another thought was, did they sometimes move the upper capstan out of the way?  In which case the eyebolts might be for attaching tackle.

Edited July 20, 2021 by Gregory

[tlevine]

I am unable to give you any insight as to the purpose of the heavy rings.  Sorry.

[druxey]

Your theory that the eyebolts were for hoisting the capstan for repair or maintenance seems a reasonable one.

[Alex M]

Hello,

 

The model above shows a double capstan, the rings are for lifting and lowering. The fore jeer capstan on two decker ships can be lowered down to make room on upper deck for i.e. boat stowage. There was a room under the capstan called capstan room.

 

 

Alex

[tlevine]

Thank you Alex.

[Justin P.]

Hi All, 

 

Just a quick question about the recent update to the Capstan documents.   It isn't immediately clear to me which part was updated, and as Ive already printed everything out Im wondering which part was updated so that I can simply reprint the effected sections.  

 

Thanks, and apologies if I missed the update notes somewhere.  

 

 

[tlevine]

Justin, three sheets have changes in them.  The changes are referenced on the pertinent sheets.  Intermediate version- Part 104 on sheet 13, Part 012 on sheet 15 and sheet 23.  Advanced version- Part 104 on sheet 13, Parts 012 and 013 o sheet 14 and sheet 23.

[modeller_masa]

Dear Toni,

I'm making 3D capstan model for 3D printer. I don't have any plan to distribute modeling file, but have a plan to upload a simple parts-assembly animation video if you allow. (non-profit) 

 

 

 

While I was transferring plans on 3D modeling data, I found some suspicious digit errors. This is so tiny that really not a big deal for scale model unless I use CNC or 3D printer. Please consider my questions for curious and light question.

 

 

(1) When I leave same width (2.5") among part 002 grating ledges, remaining edge is 1.5". It is a reason you wrote 2.62" space.

 

 

However, there is remaining edge when I let 2.62" spaces. I recalculated and optimal number is 2.75"

 

 

Of course, it is not important because we will make 1/16 or smaller scale model and 0.01" difference is negotiable.

 

 

(2) Lets put a grating in a frame.

 

 

I'm following an intermediate plan. I also checked the advanced plan, and an inner size of the A plan is 34.0 x 38.0 which is slightly smaller than I plan.

 

 

Therefore, I rotated grating, and encountered the next question... (Ignored the gap due to scaling)

 

 

From the tutorial picture, grating's direction and margin between frame and beam is quite different from plan. It is already proved that I can't follow the plan at question 2 (grating is rotated 90 degrees.), and now different size of grating frames (Part 004s and 006s) between tutorial and plan is confusing.

 

 

If I rotate it again, it overlaps beam(part 009). I would say that the grating frame on plan is a bit oversized.

 

I checked other member's work. usedtosail didn't rotate frame (3), but rotated grating(2) unlike the tutorial. You can see the grating frame (part 004) overlapped beams. (part 010s) It proves the project faithfully followed the plan.  

 

To sum up my questions,

(1) Really minor number error report. Gaps between grating ledges may vary on inner size of grating frame.

(2) Is the direction of grating important in reality? I think it is removable and direction can be changed anytime although the grating's holes aren't exact square.

(3) Should the grating frame (part 004) overlap lower beams as plan directed? Which grating (tutorial or plan) is more accurate historically?

 

(+a) Could I upload an animated assembly video of a capstan project? (non-profit, neither modeling file nor video scene file, baked video only)

 

Thanks for reading.

 

Best regards

Edited October 17, 2021 by modeller_masa