Size Issues When Converting Blocks/Deadeyes from Inches to MM

[GGibson]

As I usually start out my queries, I'll say "This is a silly question, but...".  Going to start working on the Bluenose 1921 and noticed that the parts list includes deadeyes and blocks that are supplied and measured in inches.  The parts in three previous builds I have worked on have all been measured in millimeters.  And, in all due respect, I have found that the Model Shipways-supplied blocks and deadeyes are not as good as others available.

 

With that said, in doing the conversions from inches to millimeters, for example, a 3/16" block converts to 4.76MM.  Will a 5MM block look too big?  Conversely, a 1/8" block converts to 3.175MM.  Will the appropriate size line still fit thru a 3MM block?  Do the holes significantly change that much?

 

Finally, appreciate everyone's recommendations on what they use for alternative blocks and deadeyes.  I have purchased the "Beautiful Blocks" from Model Expo, but have also looked at the "Realistic Blocks" from Ages of Sail, and the deadeye kits and specialty blocks from Syren Shipmodel. 

 

Thanks...

[David Lester]

Hi Gregg,

The Model Shipways plans for the Bluenose indicate that all the blocks were internally stropped and any pictures I've seen would appear to confirm that. If you are thinking of replacing the blocks anyway, why not use BlueJacket's internally stopped blocks. I used them on my Bluenose and I think they're great. They're made of cast metal and need to be painted. From the old photos, it appears to me that they were white, so that's how I finished mine.

 

If I remember right, I ignored the sizes of the provided blocks and took the sizes from the plans and then approximated as closely as possible from what was available with the exception of the 3/32" size, which are very small and difficult to use. I sometimes found it necessary to drill out the hole of the strop and it was almost impossible to do on this size without "tearing out" the strop. For these ones I ended up substituting 1/8" blocks and look fine and they were wasy to work with and of course, anything over 1/8" presented no problem at all.

 

You can also get internally stopped blocks from Syren, but I don't believe they are available in small enough sizes. Also, they appear to be so beautiful that I didn't have the heart to paint them, so I opted for the cast BlueJacket ones, which need to be painted, so they seemed like the perfect choice. They come with a becket, which you don't always need, so when that was the case, I just snipped it off and filed that end of the block smooth.

 

With respect to deadeyes, I also used BlueJacket's. The lower deadeyes are attached with a "shackle" type fitting and I knew I could never get a satisfactory result trying to duplicate that with wire and/or brass rod, so I opted for the BlueJacket cast ones and I was quite happy with them.

 

So that's one suggestion.

David

 

[GGibson]

Great input and info, David. Thanks!

[allanyed]

7 hours ago, David Lester said:

You can also get internally stopped blocks from Syren, but I don't believe they are available in small enough sizes. Also, they appear to be so beautiful that I didn't have the heart to paint them,

As a big fan on these old schooners this is an interesting point David.   Did the working boats paint the blocks or is this a modern convention?  I see the usefulness of paint to protect the wooden shells but was this actual practice when they were fishing industry vessels rather than modern tour boats?  Inquiring minds......

Allan

[David Lester]

I don't know for a fact that they were painted, Allan, but it's my best guess based on the old black and white photos of the Bluenose. In the first picture of my post above, comparing the blocks to the parts that we know were white, such as the rails and then to the boom, which appears to be natural, I think they look white. In any case, rightly or wrongly, painting them white was an easy approach when using cast metal blocks. It's easier to paint a white finish than a natural looking wood finish.😀

 

On the Bluenose II however, they are definitely natural. Those Syren blocks would look great finished like this.

David

 

[Charles Green]

3/16 vs 5mm; the difference is on the order of 1%.  In a side-to-side line up of several 3/16 blocks, a 5mm one in the mix may be discernable, but I wouldn't go as far as to say this difference would throw things out of scale.  Can't comment on the hole size for the lines.

[Dr PR]

For what it is worth, block sizes were determined by the size of the lines running through them. So if you know what size lines you are using you can figure the proper block size.

 

When looking at historic information on line sizes remember that the dimension given is the circumference of the rope. However some more modern books, especially ship modelling books, refer to the diameter of the line.

 

Zu Mondfeld's "Historic Ship Models" has a table of block sizes based upon line diameter on page 242. You can probably find the same information somewhere on line.