CardCat Class - X200 Stealth Drone

[DrGerryD]

Hi Guys

Had an interesting couple of days. I built a trial mockup of the X200 in 0.2mm cardboard - length just under A4 size. It was just for testing that I have taken account of all those little bits and pieces that need to be there, to work out which work processes I can do away with to make things faster, and which sub-assembly level I should choose to reduce the number of parts and make things simpler. At the same time I discovered that my fingers do not fit well inside such a small model ..:). Last time I worked on something this size was scalectric back in 1960. Maybe my fingers have grown a bit since then..:). And that leads me to a question you can maybe help me with.

How big/small models do you work with normally. These CardCat boats are new and there is no scale factor like 1/32 or whatever. So if I can get some idea at least of the number of milimmeters involved and that you all won't keel over laughing or go into a coma if I come along with something that fits A3 instead of A4.

Gerry

http://www.marlab.dk/docs/prototype_-1.jpg

[Zathros]

Hey Dr. D., could you give some more reference for this craft. I visited your website, Marlab Miniboats - CardCat (http://www.marlab.dk/cardcat.htm)

but I could not find the origins of the craft. It is a very interesting design. Almost looks like it might have good sailing characteristics with a couple of keels and some rigging! I believe it is your design then? What do you model in? :)

[DrGerryD]

Hi Zathros

Yes, I only build models of my own designs. I used to design ships professionally and in those days I used steel and aluminium. A couple of years ago I went on a pension and not having room for 4000 tons scrap metal in my back yard I went over to designing miniboats to my own designs - in meranti plywood mostly. The X200 is an original design for a stealth drone of 2400mm length which I will shortly be starting to build. Recently I became interested in designing boats using cardboard and polyester and since I already have most of the drawings for the original X200, decided to make a scaled down version for cardboard and polyester. I have not built a boat out of cardboard before so it is very interesting - and may I say more fun than I had expected.

What about you ?

Regards
Gerry

[DrGerryD]

Hi Folks

I have just completed the CardCat X200 Stealth Drone Bridge Assembly. Everything went just as it should and the site is updated (the site is now running ok - the guys at my ISP found and solved the problem) . Moving on now to the Port hull.

Cheers
Gerry
http://www.marlab.dk/videos/X200 Bridge Assembly.jpg.JPG

[DrGerryD]

Hi Folks

New progress report and photos on the boat's web site.

Marlab Miniboats - CardCat Class - X200 Stealth Drone - By Dr. Alfred G Davison (http://www.marlab.dk/cardcat_x200.htm)

Cheers
Gerry
http://www.marlab.dk/videos/IMG_4363.JPG

[DrGerryD]

Hello folks.

The first module (Forward Module) has been completed and dokumented (photos and a small text). It worked out just fine. Check out the specs for the module on the project web site. Marlab Miniboats - CardCat Class - X200 Stealth Drone - By Dr. Alfred G Davison (http://www.marlab.dk/cardcat_x200.htm)

[cgutzmer]

Hey Gerry!
Looking good :)

In regards to size you can design/build in whatever size you want :) Bigger is usually better because its easier for a builder to shrink than to blow up if he wants bigger :)

SInce these are custom boats you can figure approximate scales compared to what you think would be an appropriate sized real boat of the same style.

These could make cool plans for RC?

[DrGerryD]

Hey Gerry!
Looking good :)

In regards to size you can design/build in whatever size you want :) Bigger is usually better because its easier for a builder to shrink than to blow up if he wants bigger :)

SInce these are custom boats you can figure approximate scales compared to what you think would be an appropriate sized real boat of the same style.

These could make cool plans for RC?

Thanks for the tip Chris. I'll bear that in mind when the module size is fixed within the next couple of days. I'll just choose a scale for the figures and take it from there. By the way the final version of the boat is already looking for stealth than the version I have shown so far... As for RC - The Battery module is about to be fixed. There will be 2 modules, one in each hull - with a 4 D-Cell capacity. Because of these heavt batteries, there will be a floatation chamber in each hull of about the same size. I am trying to keep the weight of the boat below 1Kg.

Cheers
Gerry

[DrGerryD]

Hi Folks

Hurrah - the X200 Standard Module is complete. This module is the core of the various special modules which will,appear very soon. A single X200 hull contains (From the Bow)

Forward Module - contains trim ballast as neccessary
Floatation Module
D-Cell Battery Module
Floatation Module
Engine Module
In RC applications the Floatation Modules will contain expanded polystyrene. As close as we can get to unsinkable under normal circumstances.

I have made one D-Cell Battery Module, and am about to start on the other five standard modules which comprise both hulls. Here is a small collage of drawings (no photos as yet).

http://www.marlab.dk/videos/Standard Module Collage.png

Cheers
Gerry

[DrGerryD]

Hello Folks

After completion of the "module" project yesterday, and the completion of the "bridge" project last week, I now feel that I know enough about card of various types and dimensions to be able to start on the boat design proper. Cardboard is a very exciting material, with its own special problems and advantages as in any other material. So the design will not be the same as if it was made in steel, aluminium or GRP. Yes the material is very flexible - but that also means that the least little bit of stress within it because of temperature and more importantly humidity, and the whole structure warps. All that is left before I start the design work is to make a couple of old-fashioned "box girder" bulkheads and see how they stand up to the stresses involved in making them. Fortunately for me, my stress can be helped by coffee. Maybe I should spill some on the boat ... :D

Cheers
Gerry

[DrGerryD]

Hi Guys

The first component of the CardCat Class X200 Stealth Drone is complete. This is the Longitudinal CL (for Centre Line). It runs along the centre line of the boat. The longitudinal (which I will call LCL from now on as I am lazy) is composed of a piece of 0.65mm cardboard with reinforcing bars running along all edges, also in 0.65mm cardboard. These bars are glued to the LCL by 3mm x 3mm x 0.65mm "angle brackets" of 30mm length. The structure is kind of an "I Beam" in cross-section. Calculated weight 8.77 g and extremely strong and stiff for its size and weight.

Gerry
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_longitudinal_cl.JPG
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_longitudinal_cl2.JPG

[DrGerryD]

Hi Guys

The bedding is constructed, the Longitudinal Centre Line (LCL) installed and aligned both in the longitudinal and vertical axis. As you can see from the photo it will stay there until I remove it, which will be when I am ready to turn the boat the right way up again. Work proceeds on the Transverse #4 (Battery Support transversal).

Cheers
Gerry
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_bedding_2.JPG

[DrGerryD]

Project on track - kind of...

(Photo 1) Transverse 5 locked in place on the LCL. Now almost midnight. Time to get some shuteye. Night guys.

(Photo 2) If the work on the bedding and alignment is done properly the entire arrangement can by turned to any angle you choose to get at those awkward small spaces. Just the same as in virtual space.

(photo 3) When it got to this stage I dropped work on Transverse #4 and started on Transverse #5. I will have to rethink #4 ...:)

http://www.marlab.dk/videos/cardcat_x200_stealth_drone_transverse_5.JPG
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_bedding_3.JPGhttp://www.marlab.dk/videos/cardcat_x200_stealth_drone_transverse_4_2.JPG

[DrGerryD]

Hi Folks

Transversals 2&3 are in place on the LCL. The strips visible in the photo are merely there to keep alignment at the connection between the LCL and the transversals while the glue on the angle brackets is drying. These will be removed and re-alignment of the transversals will be done before the skin is attached.

Things went well today. A new construction method resulted in changes to the templates and design and this in turn led to an easier and more precise construction phase. Feedback in motion...:)
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_transverse_2&3.JPG

[paperairforce]

looking on with interest Dr. That is one heck of a paper support structure.

[DrGerryD]

Hi Folks

PaperAirForce - Thanks for the comment. Do you think it will be too heavy for the job ?

Ok guys. All of the transversals are now in place except #4 (the battery holder). I have decided to make this as a polystyrene block carved out to take the D-Call batteries and inserted through the top deck. This will provide excellent stiffening of the hull around the batteries, prevent them from moving around as the boat sails, and last but not least provide a little extra buoyancy in an emergency. So #4 is dropped altogether. After lunch I will be starting on the outer skin. I have been wondering whether or not I should use 0.2mm or 0.65mm card for that. The bridge bottom plate should be in 0.65 but the others ? I am going to try with 0.65 for everything. If it works out this will mean only one thickness of cardboard used throughout the boat - so logistics should be best.

Cheers
Gerry
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_transversals_in_place.J PG

[DrGerryD]

Hi Guys

The last frame members complete, I have removed all of the supporting structure from the bedding. The only things holding the boat down now are the four spots of glue attaching the LCL to the bedding. The bridge bottom plate and port hull side plates are installed, at the same time aligning the port hull transversals. The photo shows the bow chevron plate being glued in place.

Cheers
Gerry
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_port_construction.JPG

[DrGerryD]

Hi Folks

I reached the experience limit for the current prototype today when I completed the port hull plating. This prototype is now set aside for later when I may need to confirm something. In the mean time there are an aweful lot of changes I can make to the design to make the hull lighter without losing strength, but more importantly to make assembly simpler.

So it is back to the drawing board for the next couple of days - then start on the new prototype Monday. Have a nice weekend everyone.

Cheers
Gerry

[paperairforce]

Hi Folks

PaperAirForce - Thanks for the comment. Do you think it will be too heavy for the job ?



not sure if you mean too weighty or too heavy duty. I would not think an r/c boat needs very sturdy support, though it can't hurt and it is an impressive structure! Regarding weight, I would think the more the better since r/c boats tend to need ballast anyways - probably especially card ones. But perhaps your batteries and engine will provide enough.

may I ask, why the stealth drone classification? What little I know, that means unmanned and radar evading! One of the two is a given, but....

[DrGerryD]

not sure if you mean too weighty or too heavy duty. I would not think an r/c boat needs very sturdy support, though it can't hurt and it is an impressive structure! Regarding weight, I would think the more the better since r/c boats tend to need ballast anyways - probably especially card ones. But perhaps your batteries and engine will provide enough.

may I ask, why the stealth drone classification? What little I know, that means unmanned and radar evading! One of the two is a given, but....

That was just a bit of fun. Got carried away with the name and gave it to the boat I am about to build (2.4m remote controlled). That was an idea I had a couple of years ago for a drone which could be programmed to aid SAR operations in the Baltic Sea.
Cheers
Gerry

[DrGerryD]

Well folks

The redesign went faster than imagined despite several coffe breaks etc.

Here then are the latest and last drawings of the X200. From here on in progress reports will include photographs instead. Cutting and assembly should be considerably faster despite the boat being a little bit bigger to take account of the problem with D-Cell size.

Cheers
Gerry
http://www.marlab.dk/videos/CardCat X200 Stealth Drone - Bottom.png
http://www.marlab.dk/videos/CardCat X200 Stealth Drone - FrontView.png
http://www.marlab.dk/videos/CardCat X200 Stealth Drone - Internal Arrangement.png
http://www.marlab.dk/videos/CardCat X200 Stealth Drone - ISO.png
http://www.marlab.dk/videos/CardCat X200 Stealth Drone - Rear View.png
http://www.marlab.dk/videos/CardCat X200 Stealth Drone - Top View.png
http://www.marlab.dk/videos/CardCat X200 Stealth Drone - Without Cover.png

[DrGerryD]

Hi Guys

Went well today -the X200 frame is complete. Unless I discover a disaster somewhere there will be no further changes. Work on the skin starts tomorrow.

Cheers
Gerry
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_transversals_on_LCL.JPG
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_LP_and_SP_installed.JPG
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_LP_and_Bow_connector_in stalled.JPG

[DrGerryD]

Hi Guys

Last photos of the most current protoype. At 03:00 this morning I got sick and tired of all those teeny weeny bits that it is impossible to keep track of while maintaining some sort of pleasure from the effort. So, I have decided to construct this in another way. The basic design is excellent. It looks good, has a great hull stiffness and weighs in at a projected 150 grams. Not bad at all ! So I am keeping the basic design as it is, unless something unexpected happens. I am going to concentrate my efforts now on making it assemblable with as little pain and unregistered angle brackets as possible. I should mention here that this was also an attempt to make the boat without a bedding, and without any alignment at all. It works.

Cheers
Gerry
http://www.marlab.dk/videos/cardcat_x200_Prototype%20final%20phase%201.jpg
http://www.marlab.dk/videos/cardcat_x200_Prototype%20final%20phase%202.jpg
http://www.marlab.dk/videos/cardcat_x200_Prototype%20final%20phase%203.jpg
http://www.marlab.dk/videos/cardcat_x200_Prototype%20final%20phase%205.jpg

[DrGerryD]

Hi Guys

The change to another way of building works excellently. The stern module of the X200 is now complete and no more design is neccessary. The first photo shows the parts after cutting - yes there are only 6 parts but you better keep your tounge in while folding along the dotted lines ..:)

The second photo shows the entire aft end finished. Note that the only joints which will need to be caulked are those to the bulkhead and transom. There are no other joints in the rest which is folded from 2 pieces (the folded part makes the longitudinal stiffeners).

This is actually stronger than the previous version as the central stiffener is considerably thicker. I have already started lofting the aft midships module between bulkheads B1 and B2. If things work out the entire midships module, sonsisting of 4 "quarter" mosules will be finished late tonight or early tomorrow morning.

This is definitely a much simpler and attractive construction.

Cheers
Gerry
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_aft module_parts.JPG
http://www.marlab.dk/videos/cardcat_x200_stealth_drone_aft module complete.JPG

[paperairforce]

fascinating process Dr.! that design above looks incredibly strong and well built. and a funny thing happened....I can see it just fine, but my radar isn't picking anything up...hmmmm

[DrGerryD]

Thanks paperairforce - it is always nice for a backroom boy to get a pat on the back from people who knownwhat they are talking about. :D

Update. The aft midships module is complete and connected to the stern module both by glue AND staples. The structure is indeed extremely strong for its weight as you will see from one of the enclosed photos where I test its longitudinal strength with 5lbs of canned vegetables. At this point the hull weighs only 85g. There is not enough room yet to load the hull transverse but arm pressure from this weakling could not provoke any sign of deformation.

http://www.marlab.dk/videos/DSC00010.JPG
http://www.marlab.dk/videos/DSC00011.JPG
http://www.marlab.dk/videos/DSC00012.JPG
http://www.marlab.dk/videos/DSC00013.JPG
http://www.marlab.dk/videos/DSC00018.JPG
http://www.marlab.dk/videos/DSC00017.JPG
http://www.marlab.dk/videos/DSC00016.JPG

[DrGerryD]

Hi Guys

The forward midships module was finished and attached to the hull at about 0100 this morning. Photo shows.

I have just completed revision of the drawings for the finalmodule, the Bow module, and after a coffe break will be getting on with that. More on that later.

http://www.marlab.dk/videos/DSC00019.JPG
http://www.marlab.dk/videos/DSC00018.JPG

[DrGerryD]

Hi Guys

A noteworthy day. The construction phase of the CardCat X200 Stealth Drone hull is finished. I connected the Bow Module to the rest of the hull about an hour ago. Now I will mode on to the canopy while the glue on the assembly cures. This will take about 12 hours. The glue is dry after only a few minutes but first reaches its plastic-like state after 12 hours.

http://www.marlab.dk/videos/DSC00019.JPG
http://www.marlab.dk/videos/DSC00021.JPG

[DrGerryD]

Hi Guys

I have now tested 6 typed of caulking paste and finally went for the ordinary silicon based stuff I use for wooden boats. That should not surprise since wood and paper are closely related. After caulking the prototype I can only say - I am still not satisfied with the result. Technically speaking - yes - I have reached the technical targets I set. But the results are not at all pretty as you can see from the photos in the previous posting. So now I go back to the drawing board once again and try to see this aspect while maintaining the technical and assembly improvements. This means that the intention of splitting the templates up into A4 or A5 sizes will have to wait this time around. The sheets of card I use are 1000 x 700 mm so For this next construction I am going to use a whole sheet without cutting it us first. I should get the whole boat out of one sheet with hopefully at least a 9.5 for artistic impression.

[DrGerryD]

Hi Guys

I have now tested 6 types of caulking paste and finally went for the ordinary silicon based stuff I use for wooden boats. That should not surprise since wood and paper are closely related. After caulking the prototype I can only say - I am still not satisfied with the result. Technically speaking - yes - I have reached the technical targets I set. But the results are not at all pretty as you can see from the photos in the previous posting. So now I go back to the drawing board once again and try to see this aspect while maintaining the technical and assembly improvements. This means that the intention of splitting the templates up into A4 or A5 sizes will have to wait this time around. The sheets of card I use are 1000 x 700 mm so For this next construction I am going to use a whole sheet without cutting it up first. I should get the whole boat out of one sheet with hopefully at least a 9.5 for artistic impression.

[DrGerryD]

Hi Guys

Instead oi just caulking the seams with the silicone sealing compound I opted for covering as much of the hull as possible. This is certainly a watertight hull now ! The covering will be sanded down when it has dried for a couple of days. In the mean time it looks as if it was hand moulded with GRP without a gel coat. It is going to look fine. I decided that the update of the drawings was of a higher priority than making the canopy so I have started on that.

http://www.marlab.dk/videos/DSC00023.JPG

[DrGerryD]

Hi guys

I spent today looking into another way of construction of the hull. Hoping to avoid those ugly module joints by constructing the boat skin of only longitudinal sections. As you can see in the photos this worked. However, the price is too high, in that it was impossible to reach the deepest parts of the hull to ensure correct gleuing and the structure was to unhandy to handle easily. So I am going back to the modular approach as the best (also for small workshop tables) but will now look deep and hard at the module interface and find a better way of carrying this out.

http://www.marlab.dk/videos/DSC00028.JPG

[DrGerryD]

http://www.marlab.dk/videos/DSC00029.JPG

[DrGerryD]

Hi Guys

The final version of the X200 stern end (will add Kortz Nozzles later when the entire boat has been assembled). This also has the canopy installed. An approved assembly method has now been created and used. This is a stand model so no engines or batteries or R/C gear will be installed. I will probably use it as a display of some kind. Now on to the twin midships modules.

http://www.marlab.dk/videos/DSC00030.JPG
http://www.marlab.dk/videos/DSC00031.JPG
http://www.marlab.dk/videos/DSC00032.JPG
http://www.marlab.dk/videos/DSC00033.JPG

[DrGerryD]

Hi Guys

The "production model" of the CardCat X200 hull is complete and now ready for painting. I have decided to leave the hatch covers out as I want viewers to be able to see the internal structure of the boat. The Kortz nozzles and rudders are included but not the drives and propellers. This is as far at we can go without investing in the technical equipment, like engines, batteries and RC gear. I just had to include a photo of the mess after the battle with plating. Just to show that not everything is organised around here.. :D I am going to have to wait for the technical stuff until I can afford it. In the mean time I am going to use some of the experiences learned from this project to change a few things in the "real" X200 (that's the 2m version in Meranti) or since I found this cardboard thing quite challenging and interesting, I may make a larger version of one of the monohulls and use this as a standard for the entire class. More photos and final specs when the paint job is over.

http://www.marlab.dk/videos/DSC00054.JPG
http://www.marlab.dk/videos/DSC00055.JPG

[DrGerryD]

Hi Guys

Have I bored you all to death with these reports ? If I have then I will tone it down a bit for the future.

Cheers

[legion]

No, not bored at all! It is interesting to see it 'evolve' and come to life!

[DrGerryD]

Hi Guys

Have dug out the paint I need for the X200 from the cellar (with the aid of my wife since I am unable to manage stairs at all) and will be starting painting the X200 tomorrow morning. The colour scheme will be off white internally and camo externally.

[DrGerryD]

Hi Guys

There is no doubt about it. The 900mm version of the X200 (named X900) is one mother of a cardboard hull. Made in 2mm card the parts are not only glued together but also pop-rivetted with 3mm aluminium pop rivets. Here for example is the drawing for one of the 4 bulkheads in the boat. The small holes show the locations of the pop rivets. The projected cargo capacity of the boat will be around 14Kg - a humongous capacity for such a small boat whose projected weight will lie around the 2Kg mark. This will be an extremely sea-worthy hull, and I mean SEA-worthy. I may begin marketting this as an environmental monitoring boat for use in sensitive areas like bird colonies etc. We shall see. I have to build it first..:D (You can probably "hear" that I am looking forward to that.

In the mean time I have painted both the last prototype and the "production" versions of the X200 with their first layers of terpentine based paint (green). This weekend I expect to add brówn and maybe some black in a camo pattern. Both will be float tested in the kitchen sink when ready (no need to break out my 8foot inflatable swimming pool to test these hulls). The last prototype will be used to measure trim/load and displacement values. More on that later. The other will be used only as a demo model.

I will be starting a new project thread for the CardCat X900 Stealth Drone when I start building it next week.http://www.marlab.dk/videos/X900-B1.png