You might try this link:

http://leow.de/friends/John/AS29JR3.html

let me know if this works for you.

John Evans wrote: ... perhaps a reddish sail as the scale seems appropriate.

When I was in the process of converting, I posted some drawings to the junkrig yahoo group. One shows the Center of Effort of  a single Reddish main compared to the Bolger gaff yawl.Another drawing shows a smaller main sail and enlarged standing lug mizzen. 

https://groups.yahoo.com/neo/groups/junkrig/files/Twilight/

If you decide for a single sail rig, you may use the sailcut8 program to modify the traditional/Reddish design: make the battens longer and the luff shorter. The halyard needs some free space to swing around the mast.

The scantlings of the Bolger mast are too skinny IMHO. You may think twice before you hang too much sail on it. 

As a carpenter you might have some scrap material laying around. Why not screw some wood and a sheet of plastic together, haul it up your mast and see how it behaves?

From time to time I put some video on youtube. Search for gassho88

btw we love our mizzen :-)

Leo

Dave Zeiger wrote:

Hi John,

A few thoughts:

RE AS29: In my humble opinion, the AS concept is one of the great maritime innovations of the last century. Bolger wrote that he thought the MANATEE was contending successor to the Herreshoff MEADOWLARK (a cruising design for amateur DIY). I consider the AS line to be very much more so, especially in the age of second growth timber.

RE Ease of conversion - I'm with Arne. Should be easy enough to convert the main to junk. The mizzen can be left as is (more on this later)... it's hard to beat for simplicity.

RE Balance - Phil (Bolger) is using his standard 'trick' in the AS29 rig. The mizzen is either all standing or struck. The main is designed with a diagonal leech... as you reef, the center of effort moves forward as area is reduced. Net effect is to maintain overall balance against the constant area of the mizzen.

To reproduce this effect, one of the junk sailforms with a diagonal leech would help. Quadrangular sails - such as seen on many traditional craft, Slocum's LIBERDADE, and Bolger's usual junk sail choice - seem to be off the JRA radar, but I'm not sure why. Possibly due to reefing geometry considerations mentioned in Hasler/McCleod? Pics I've seen of traditional boats so rigged seem to furl without trouble.

W avoided the issue on LUNA (AS31 following the AS29's lead) by using two large sails (cat schooner, in that case) which can be balanced against each other.

In practice, it's likely you can sail under well trimmed main of any shape (e.g., a Sunbird or Reddish sailform), and adjust mizzen balance via its sheets, under and over trimming as necessary. I think it will be a matter of nuance.

Conversions to JR often allow an increase in sail size, as it's so quick and easy to reef (Bolger endorses this approach). By adding balance and extending aft, you'll pick up considerable area over the original gaff rig. If the resulting aspect ratio seems low, you can always go up.

RE Mizzen - Consider a somewhat larger mizzen, especially if it must overcome balance issues mentioned above. We also wished we had larger one on LUNA to counter the considerable forward windage of the furled JR sail bundle, wind-cocked or at anchor.

Maybe start with a taller mast and Tyvek mizzen till you get a size that fits? Can always cut down!

We had great luck setting the mizzen with no haulyard. We fixed a light line at the masthead, led to a cleat low on the mast.

To strike sail, push the inbrd end of the sprit vertical (bring iits outbrd end down and to the mast). Roll up the bunt, and spiral wrap sail and sprit to mast using the light line. Cleat off and done. 'Whip' the line in high winds to get first wraps as high as possible.

RE Leeboards: We love 'em!

A retaining cable (our preference) or bar means you don't have to tend them between tacks (they become Off-Center Boards, rather than lee boards).

We find that they tend to perform better when placed further forward than I expect. In both LUNA and SLACKTIDE, we still have a little lee helm with sails trimmed for the wind and boards all the way forward. Have to crank some weather helm in with over trimmed after sail.

I notice board placement is far fwd in Thames Barges and many others of similar type... could be an effect of the very firm bilges?

Consider spanning bulkheads with your (leeboard) guards. We didn't on LUNA, and an... er... intimate encounter with a dock pushed the unbacked guard into the hull hard enough to crack veneers. Looks like the AS has plenty to choose from. Never hurts for the guards to go longer than necessary to reach the next blkhd... they make great boarding steps!

*****

Hope all this helps... good luck with the conversion!

Dave Z

Thanks for posting Dave, I have tried to email you through your website but I can't seem to get one to send. I am not very good with computers, my wife laughs and says I am a "luddite". I would really like to see some close ups of the hardware and leeboards on Luna and slacktide if you are not too busy with your build. Yes I agree spanning the bulkheads would be good insurance. What type of wood did you use and how free from knots was it? As for the mizzen how about a traditional sprit sail and simply scandalize it to reduce sail?

Just came across this thread and would like to go back to the original posting. My questions are: What kind of sailing do you have in mind? Is there a main mast already that you can use? Is the tabernacel built in the bow? Leo

Karlis Kalnins wrote:

I find it very interesting that it represents this alternate western JR lineage. Was there ever crossover, did VanLoan read Hasler or vice-versa? I wonder what  Chris Gallienne has to say on the subject.

OK, now you got me started.

This is a very interesting question. It’s very easy to generalise that in the early days of the development of the Western junk rig (1960’s) US junkies followed the South China/Hong Kong model a la Tom Colvin/Michael Kasten, whilst over on this side we followed the model of Hasler & McLeod - a more rectangular  (North China) pattern, albeit with triangular top panels. The examples of Van Loan in the US and Dmitri LeForestier in Europe show this theory to be an over-simplification.

I have no idea why Blondie Hasler adopted for Jester the sail plan he did -– it has been likened to the tall rectangular sails of the north Chinese riverine junks, although his sailplan differed in having convex luff and leech. Hasler’'s later designs, e.g. for Ilala and Redlapper, had straight parallel leech and luff. This then formed the model for his ‘'standard’' sailplan, with the yard raised to a higher angle and triangular top panels, developed with Jock McLeod from the mid-sixties onward and first seen on Galway Blazer.

The single sailplan presented in 1981 by Derek van Loan, apparently based on his work with the junk rig since the 1960’s, is very similar to that of Ilala/Redlapper, with a slightly higher yard angle. Perhaps the originator of this rig saw Ilala in the US in 1964? Who knows? It is also a little reminiscent of the shape of Newbridge’'s so-called ‘Hi-Power’ rig - although Van Loan pre-dates this rig - and like that one, seems to have been something of an evolutionary dead-end. Having said that, given that Van Loan’s book ran to 4 editions it must have had some success. Does anyone know of any that were built and sailed extensively?

Van Loan points out that, rather than being riverine Chinese in origin, this was the basic sail shape of the ocean-going trading junks. Of course those sails were implemented in very different materials on very different hulls. The Van Loan sailplan, together with the similar ones from Jester & Ilala, would seem to be completely sub-optimal when executed in Western materials and built flat. Hasler himself said that Jester did not go well to windward. I wonder, however, how many boats of her size with more ‘modern’ Western junk rigs, could make the Atlantic crossing, using Hasler’'s northern, windward route, in less than 38 days?