Subject: SMML VOL 2754 Date: Tue, 15 Feb 2005 03:26:18 +110 The Ship Modelling Mailing List (SMML) is proudly sponsored by SANDLE http//sandlehobbies.com For infomation on how to Post to SMML and Unsubscribe from SMML http//smmlonline.com/aboutsmml/rules.html ---------------------------------------------------------------------------- MODELLERS INDEX 1 Alarm/Fowler Wheel (again) 2 Re USS Alarm "Fowler Wheel" propulsion 3 Question about ORP "Piorun" 4 Re Fowler wheel 5 Re Deck Planking 6 David Brown / Model of HMS DANAE / Sandown Park Exhibition Dec 2004 7 Re Seawolf propeller 8 Re Seawolf propeller 9 Re USSR Subs in 1/350 10 Help Wanted 11 U.S.S. Alarm 12 Hunt class type 2 and 3 13 Seawolf propeller ---------------------------------------------------------------------------- MODELLERS ---------------------------------------------------------------------------- 1) From "JAMES HATHAWAY" Subject Alarm/Fowler Wheel (again) I looked at the picture of Alarm in drydock, and I noticed she does have a rudder boss, and hinges, but I am beginning to wonder if it was fitted. If the screw works as I was thinking, with a ramp and roller arraingement changing blade pitch in the rear of the rotation arc, simply changing the orientation of the ramp, or cam, to the centerline of the ship, would change the angle of thrust. It would have an all axis capability because it could vary it's thrust anywhere within the arc. The fowler Wheel may have been a true cycloidal screw, and able to provide thrust at any angle rendering the rudder unneeded. Unfortunatly I am unable to find any other mention of the system, it was obviously experimental- Jim Hathaway ---------------------------------------------------------------------------- 2) From "David N. Lombard" Subject Re USS Alarm "Fowler Wheel" propulsion >> The second photo on the page shows the stern of the USS Alarm and the "Fowler Wheel" propeller. Anyone out there know how that thing works? I'm fairly good mechanically and understand the real basics of how a propeller works, but that thing looks like it would just churn water, not move a ship! << I suspect the modern-day incarnation of this is the "Voith-Schneider" drive. These are used on some *highly* maneuverable tow boats. A working model boat verion of this is described here http//www.harbormodels.com/Harbormain/Templates/m18.htm along with three models than use them http//www.harbormodels.com/Harbormain/Templates/graupner/gr2.htm http//www.harbormodels.com/Harbormain/Templates/hb/hb8.htm http//www.harbormodels.com/Harbormain/Templates/hb/hb9.htm David N. Lombard Rossmoor, Orange County, CA http//www.fourmilab.ch/cgi-bin/uncgi/Earth?imgsize=320&opt=-z&lat=33.8&ns=North&lon=118.08&ew=West&alt=7&img=learth.evif ---------------------------------------------------------------------------- 3) From Tim Stoneman Subject Question about ORP "Piorun" Piotr asked about PIORUN's colour scheme. I've seen little on the Internet to help; a good reference is Mariusz Borowiak "Biate Stonie 5 ORP Piorun" (Warsaw Biblioteka Magazynu Morza, 2000) - text is in Polish, with several photographs and 6 drawings of some of the ship's various colour schemes. The drawings are useful for colours, but do not show changes in weapons, radars etc. For details of paint names, see the Ship Camouflage website at http//www.shipcamouflage.com/ and select 'S&S Paint Chip Sets' or 'Colourcoats Paints'. For accuracy, the Colourcoats paints are strongly recommended; failing that, there's a conversion chart, which gives approximations from other paint manufacturers, at http//smmlonline.com/articles/royal_navy_paints.html In summary, at various times PIORUN wore Overall AP507B (a medium grey) with a small Polish flag on each side of the funnel Variations on the Western Approaches scheme (white and Western Approaches Blue) both with and without the Polish flag A modified Light Admiralty Disruptive scheme in 1943 A Light Admiralty Disruptive scheme for 'J'/'K'/'N' in 1944 A Special Home Fleet Destroyer Design' in 1944 An 'Admiralty Standard' scheme in 1945 Examples of other ships in some of these schemes can be found on the Navyphotos website http//www.navyphotos.co.uk/index12.htm KINGSTON (AP507B) DOUGLAS (Western Approaches) SAUMAREZ photo2 (Light Admiralty Disruptive) OBEDIENT photo 1 (Special Home Fleet Destroyer Design') ULSTER photo 1 (Admiralty Standard) (Note the actual patterns carried by some of these ships varied from those worn by PIORUN.) Tim Stoneman ---------------------------------------------------------------------------- 4) From Fritz Koopman Subject Re Fowler wheel Hi Larry! The Fowler wheel was the original concept that ultimately wound-up being refined by Viennese engineer Ernst Schneider. With Fowlers design, the blades were hinged, and a cam was attached to the vertical shaft to change the attack angle of the receeding blade as it aproached centerline. A neat concept, however one that proved highly inefficient. While one blade was creating thust, the other three were at zero attack and basicilay creating drag. Another issue discovered was that as the aft blade was at attack angle going right to left, a drag componet to the right was created, causing the stern to crawl to the right. This had to be compensated by the rudder, which would need to be hard over at flank, causing (you guessed it) more drag and inefficiency. To make things realy ugly, materials were not quite ready for this either. The intermittent pulsing by the blade tended to cause "undesirable" vibrations, as well as tearing the bearings apart quite quickly. Also, as the cam levers were attached only at the top of the blades, the resultant torque on the blades had a tendency to snap them in half. Alas, the system also did not work in reverse. -) In 1926 with advancements in materials engineering, Schneider worked out a different cyclic system for blade control that would allow both the receeding, AND advancing blades to change attack angle, in either direction. This improved efficiency as well as eliminated the crawl issues. After several tests, a few small changes were made so that the cyclic control not only worked in the fore and aft direction, but in any direction chosen, eliminating the need for a rudder, for turning, with one prop, as well as allowing complete contoll over the direction and attidude of the vessel with two. (fore, aft, turns, SIDEWAYS, and anything in between). These systems still lack the straight ahead efficiency of an ordinary screw, however the unlimited manueverability makes the system popular for tractor, and harbor tugs, as well as offshore vesels in need of position keeping. They've been manufactured by Voith since 1928, starting with its first installation in the vessel "UHU". Best regards Fritz K ---------------------------------------------------------------------------- 5) From "William H. Shuey" Subject Re Deck Planking >> do you mean actually gluing the printed sheet on the deck? << FWIW This is an old time method of making planked decks for wood ship models. Use a heavy paper and draftsmen's pens and india ink and draw the complete deck on paper. Cut it out and glue it to the wood hull. I remember a friend doing a repair job on an old professionally built model of a dreadnought battleship, Texas I think, and the original decks had been paper. They were coming loose and were very dry and brittle, he had a time salvaging them. Later version was to make the deck in thin wood sheet, rub in white or light gray paint and when dry draw the deck planking on with a draftsmen's pen and brown india ink. Afterward, over spray with matt varnish. Worked rather well. Note we are talking about 1/192 scale models here, but shrinking the drawn pattern down on a modern copier should work. Just be careful what you over spray with as some varnishes will cause the copier ink to run. Bill Shuey ---------------------------------------------------------------------------- 6) From "Noel Paris" Subject David Brown / Model of HMS DANAE / Sandown Park Exhibition Dec 2004 I have recently read with interest, in the monthly issue of Escort No49, about the model of the Leander class frigate HMS Danae constructed by Mr David Brown which was exhibited, together with another model of his depicting a Hunt Class Minesweeper, at the Sandown Park Exhibition in December 2004. As I wish to make contact with Mr Brown, I would highly appreciate if any of the SMMLies can kindly assist with providing Mr. Brown's e-mail or postal addresses. I can be contacted at paris@onvol.net Best Regards Noel Paris ---------------------------------------------------------------------------- 7) From "keith bender" Subject Re Seawolf propeller Hi SMMLies, As to the Seawolf propulsor on the Trumpy kit. I have worked at EB while Seawolf and CT were being built. As a machinist there I had the opportunity worked on sections of the propulsor. That unit is very classified. All I can say without getting myself into more trouble over it is that the kits propulsor is pretty good. I can say the proto type has a seven blade propeller and a few extra goodies but I won't go no further. The stators fore and aft are fairly close and is close enough for a model. The number of stator blades the kit has is close too. Problem I have being a model builder is I want everything to be as exact as possible. People sometimes call me a "rivet counter" among other things. Yes I could make an accurate SSN 21 propulsor but I wouldn't dare. Having the dimensions in my head is fine but what am I going to do with them. Sure I could build an accurate model of it and even show it. Then you have the chance that some day some NCIS people will show up at your door asking question for about an hour on a Saturday night and asking to see your shop and all when least expected as it already happened six years ago. Let me let you all in on a little secret and this is what EB does when she is drydocked or even just pier side still in the water. They put a tarp over the inlet and outlet of the propulsor. This way it is always secure. Trust me the blade count is a big issue with them. Every model I built for EB or the skippers of the boats had these tarps modeled and that solved any problem of the interior of the propulsor. Now on the other hand being the ship lover I am and a person who loves very different and technical things aboard vessels which makes a challenge to model, well I have a difficult time not building this unit. I also wish I could share it's info with the rest of you guys and gals who want to build one. But trust me when I say it's an awesome but simple piece of equipment. VERY VERY QUITE and FAST ! And I'm glad it's on our side, Keith ---------------------------------------------------------------------------- 8) From Ives100@aol.com Subject Re Seawolf propeller >> I just got my first look at the 1/144 Seawolf. One thing I really noticed was the less than spectacular propeller. It looks terribly flat to me with virtually no pitch to the screws at all. Does someone have a drawing of the same type of propeller so I can construct a more accurate one? The one in the kit just doesn't look right. << The blades on a pumpjet are fundamentally different than the 7 bladed screws on earlier SSNs. A pumpjet has three components, a set of moving blades (rotor), a set of stationary blades (stator) and shroud assembly. Pump jets are more efficient than open propellers. IIRC, there should be 11 shorter blades (as opposed to 7 scythe shaped blades on a conventional propeller) with a more modest pitch. The blades should widen somewhat near their tips and the stators are post-swirl design, that is positioned behind the blades toward the rear of the shroud. Unlike open propellers, the duct allows the rotor blades to be loaded out to their tips, and the pumpjet has a narrower diameter than an open blade system. The post swirl stators operate with a minimum of torque inbalance under a wide range of operational conditions. Pre-swirl units are somewhat quieter. On the other hand, post swirl units cavitate at higher velocities (RPMS) than the pre-swirl unit, and thus are quieter in that aspect. I have some technical details on pumpjets, let me know if you need to see more. I haven't seen the Trumpeter kit itself, but in speaking with someone who is intimate with details of the Seawolf, they missed on a number of items. It would not shock me if the pumpjet was one of them. I believe the Yankee Modelworks SSN-21 version is much superior, and the pumpjet fairly spot on in that case. I do know of at least one (possibly two) correction kits for the Trumpeter Seawolf in the works, but I'll say no more. Last time I brought that up on SteelNavy, I got such a firestorm of crap that I swore off that site and deleted it from my browser favorites. Tom Dougherty ---------------------------------------------------------------------------- 9) From Ives100@aol.com Subject Re USSR Subs in 1/350 >> To my great surprise I found a Russian model maker yesterday at the Nurnberg Toy fare, that have launched a series of Russian Subs in 1/350. The company is called ALANGER and the models look real good. I had a chat with the people and one of the responsible is former Soviet Sub commander and it was pleasure to talk to them. The models are highly detailed and far superior to the Dragon models. The Commander assured me that the models have been well researched and that the model makers had access to the Russian Sub bases and that the models were accurate to the last detail. << Oliver, Sounds wonderful! Could you please find out if they have a distributor in the west, or how we might obtain these kits? Do they have a website for orders? Are these in resin or polystyrene? Thanks so much for sharing the information with us. Tom Dougherty ---------------------------------------------------------------------------- 10) From "dengar" Subject Help Wanted Are there any German Destroyer fans here? I am looking to add further details to a large scale model of the Z-39, I have a lot of data but are keen to swap what I have for anything new. Any help would be very appreciated. Contact Gary at dengar@xtra.co.nz ---------------------------------------------------------------------------- 11) From "John Wressell" Subject U.S.S. Alarm Interested in obtaining plans of the USS Alarm (1874), does anyone have any suggestions. John Wressell wressellco@att.net ---------------------------------------------------------------------------- 12) From "Quirk, Chris" Subject Hunt class type 2 and 3 I would like to attempt a Hunt Type 3 using the 1/700 BResinsa Type 2, I am not sure if the aft deckhouse needs to be repositioned further aft to make room for the torpedo tubes fitted amidships, any advice or suggestions much appreciated! cheers Chris ---------------------------------------------------------------------------- 13) From AAA Hobby Supply Subject Seawolf propeller If anybody provides a drawing of the propulsor pod internals it'll likely cost them 20 years of their life. There is a reason the propulsor on the kit looks the way it does ... IT'S A SECRET!! I am releived that the Chinese don't know what it looks like, yet. ---------------------------------------------------------------------------- Check out the SMML site for the List Rules, Reviews, Articles, Backissues, Member's models & Reference Pictures at http//smmlonline.com ---------------------------------------------------------------------------- End of Volume