25.5" Exceed Flowmaster Catatmaran

[LagoRSMViking]

HUGE Thanks to member studioRS/Thompson for posting his inspiring build with photos - https://forums.offshoreelectrics.com...0mm-build-help

I decided to snag an Exceed Cat for myself to see if I could design it well balanced and fast.

[LagoRSMViking]

20180613_151350.jpg

Equipment:

Graupner X-8E 4 Channel 2.4GHz HoTT Color TFT Surface Radio. https://www.graupnerusa.com/4CH-2.4G...y-S1008.H.html
Graupner Temperature & Voltage Sensor comes with the X-8E radio. https://www.graupnerusa.com/Sensor-c...age-S8362.html
Graupner HoTT Alpha GPS and Vario Module. https://www.graupnerusa.com/Real-tim...ore-S8437.html
Leopard Motor, LBP2860/2730KV 2Y, 60A, 1300W https://www.offshoreelectrics.com/pr...?prod=leo-2860

[LagoRSMViking]

Exceed Cat layout 001.jpg

Adding a water inlet on the starboard sponson and cut off the stock location for the ESC. With the stock ESC location removed I can slide the battery forward and back to adjust for COG.
OSE single water inlet. https://www.offshoreelectrics.com/pr...prod=ose-80400

[LagoRSMViking]

Working on overall COG before I remove everything and add Kevlar Carbon throughout the inside. https://hobbyking.com/en_us/3k-carbo...g-m2-1mtr.html
Running and setting up the boat with 2, 3s batteries in parallel. http://www.store.revolectrix.com/Pro...eOxide-Edition
Added spark proof XT90 connectors to the batteries. https://hobbyking.com/en_us/xt90-s-a...pairs-bag.html
Added OSE 2860 XL Aluminum Water Jacket. https://www.offshoreelectrics.com/pr...-2860XL-jacket
Replaced OEM narrow water cooling tubing with larger OSE diameter. https://www.offshoreelectrics.com/pr...ng-1%2F4-clear
Replaced OEM rudder servo with Graupner. https://www.graupnerusa.com/DES-658-BB,-MG.html
Replaced OEM 60A ESC with SEAKING Pro 120A ESC. https://www.hobbywingdirect.com/coll...nt=30055448785

[studioRS]

Looking good!

Graupner X-8E 4 cool radio, that will be fun. I ran a Sanwa MX-V with the waterproof Rx. If you don't want to run a balloon, you could cover your Rx in Corrosion-x, might help.

Spend the time to lay down the inside carbon reinforcements and get some glass and epoxy into the tips —*!**keep it light and tight. Then, stuff with foam.

[Old School]

My son did a rebuild on the Exceed Flowmaster. He also stripped the interior and we did a carbon fibre inlay. We fitted a TP Power 2940 1780kv running 6s (2 off 3s in series with one in each sponson). The motor just fitted under the canopy. He also used the same 120 amp Pro ESC.

The stock driveshaft is too fragile and lasted one run with the flanged bearings exiting the strut tube. Upgraded to a 4mm flex running through a rotating bushing. I modified the stock strut to take the homemade bushing. The rudder mount area was considerably reinforced and a threaded plate fitted making rudder mount removal very simple.

He fitted telemetry and at last run recorded 93 klm per hour. He feels that there is much more development but has switched interest to other new builds for the moment. Once all the gear is fitted there is no room left under the cowl. He may also have a build thread.

[hughb]

https://forums.offshoreelectrics.com...owmaster-650mm

Yes all the wooden internals were stripped out leaving the bare fibreglass. CF inlay, and filled the tips with epoxy/chopped CF mix. I feel we may have poured too much into the tips, with the boat hanging down vertical, we poured it in until the epoxy went up above the tips and flowed into the central part of the hull between the tips. This was done to reinforce the seam in that area, as apparently seam failures in cats in this area can be a problem. I'm getting about 60MPH which is fast for such a small hull so the extra weight I think actually helps to keep the nose down and prevent blowing over. I also cut pool noodles to be an exact fit under the deck which helps to make the whole unit more solid and there is no flex in the deck now.

Be careful with the air intakes. I love the look of them so reinforced under the hatch where they mount to spread the load over a bigger area on the hatch.

Also with the stock drive setup you won't be able to setup a neutral strut angle, it will always be negative. To remedy this we had to take out the stuffing tube and make a new one with more of a curve and remount the engine mount, also upgraded to 4mm shaft. Big job but worth it to have some adjustment. I don't have any updated photos with the new driveline in the link above.

Overall its a great little boat, very eye-catching and scale look which i love.