Exceed Racing Flowmaster Catamaran 650mm build help.

[studioRS]

Located some inexpensive carbon steel Kevlar shears by Clauss for $18 on Amazon, thanks for the tip. Also nice for all the kind notes on CF / Kevlar fitting process. I might use pink foam carved to fit in each sponson and bow nose area and glue in with Gorilla Glue, then it won't heat up the thin FG hull. Used this method on the Breathless build.

I'm only fitting a slightly longer (by 15mm) and not that much more powerful motor. I studied the glued in wood, disturbing this even in the slightest pull produced small resin crack sounds, but thankfully no stress cracks on the outside, so I left it alone. I'm going to leave all wood installed as is. Mostly a time issue for me at this point. Also, the glued in wood adds to the FG hull strengthening there already. I'll lay in carbon fiber kevlar 3k all around on any exposed FG surface I can reach, leaving the wood as is. Need to decide on System Three or US Composites 635 epoxy. I know this might be the not preferred method for ultimate strength, I just don't need to over build it, or over remove and then over rebuild it, just reinforce what is already there. I do too much of that stuff (and time in the hobby shop away from my family…) on my scale sailplanes!

Because the 2860 motor is longer and heavier, the only thing that might need adding is a rear tail clamp for added support. I ordered a single rigger mount for 28mm motors that looks trick from Kintec Racing. Also ordered some TFL props and a better collet for the motor/flex. Photos when parts arrive.

[studioRS]

I would really recommend getting Kevlar shears as it will be 50 times easier and you will get a neater cut too, but for a one off project it can be cut with fresh sharp razor (not scalpel) blades at a low angle on a cutting mat (not a wooden board), use very light pressure going over the same area again and again till it is through before moving on, and changing out for a fresh blade frequently.

I tried cutting some of the CF Kevlar last night with some Titanium scissors laying around the house, phhht! This stuff is like superman cloth, stops bullets, dang. I see what you mean.

[grsboats]

here's a tip I use to do when cutting kevlar: aplly CA glue on the cloth where you want to cut,wait some time till the glue dries....you will see how easy becomes this task but kevlar scissors is a must if kevlar is part of your work as mine.Gill

[studioRS]

Gill, Thank you for this CA glue tip I will try this. I use CA glue and thin cloth or fiberglass to stiffen scale sailplane parts and can see how this would work.

[TheShaddix]

Hey guys, I thought I would mention one thing, the CA method has one major problem that I have found. Once dried, the cloth becomes rigid and brittle, you can't bend it much anymore or it starts to crack and breaks the fibers. It does help avoid the fraying but there are better ways. If you're using this for an inlay, grab some fabric glue at a crafts store, they have a lot of different types to prevent fraying on fabric but it works the same for carbon too. You want the cloth to remain perfectly flexible to conform to the hull contours.

[studioRS]

Nice :-) Planning this weekend to go kevlar shear shopping and now to a fabric store, krickey!

[wingnut]

kinda off topic but hows the little dumas atlas coming? what have you got planned for it? thanks carl

[studioRS]

Aha, keen eye on the vintage Dumas Atlas Van Lines! I've had that kit for ever and dusted it off and started to get after it. Gutted the center bulkheads for more room and plan to drop in a small inline brushless motor, make it FE of course. The Mahogany is so brittle though, and will use ply when needed. I'll lay down a section of 1/32 birch ply down the center and fill the sponsons with foam. In true vintage form I will use the remaining mahogany. I'll make another thread for this.

Back to the Exceed... Got my CF Kevlar from HK and the Kevlar shears, new water jacket is on and just waiting to buy a big refill of epoxy.

[wingnut]

i have a the atlas and the thriftway so ill look forward to the other thread. thanks carl

[Meniscus]

Do you mind taking a picture of the underside, showing the steps? I'm also curious to see a transom shot showing the steps. I've looked a few time online and have yet to find pictures from these angles.

As for the comment regarding 85k RPM. Please note that no brushless motor should go in excess of around 50-55k safely because of the bearings. For most sport setups, 32-36k unloaded RPM will be more than sufficient. More typical setups are from 30k to 33k and deliver plenty of fun without always worrying about flipping the boat. In case any reader is not aware, you multiple KV times the voltage to get the unloaded RPM.

So far as setup and lower amp draw, a 36mm motor would be good running on 4s. Apply the typical setups for the Blackjack26. There are lots of affordable motors out there for this size. Also, the UL1 power plant would be a good choice for a model like this. Both the original Blackjack 26 and the UL1 employed 6-pole motors which, because of their torque, pulled less amps.

[Meniscus]

Another thought to consider. You mention running 3-blade props. Keep in mind that as a rule of thumb, 3-blade props pull more amps than the 2-blade props.

[Brushless55]

Man that is a killer little CAT !!
and not that bad of a price

I might have to get one to go with my DF23
and maybe try a sweet heli 3300kv outrunner on 4s with a small prop

[studioRS]

Do you mind taking a picture of the underside, showing the steps? I'm also curious to see a transom shot showing the steps. I've looked a few time online and have yet to find pictures from these angles.

As for the comment regarding 85k RPM. Please note that no brushless motor should go in excess of around 50-55k safely because of the bearings. For most sport setups, 32-36k unloaded RPM will be more than sufficient. More typical setups are from 30k to 33k and deliver plenty of fun without always worrying about flipping the boat. In case any reader is not aware, you multiple KV times the voltage to get the unloaded RPM.

So far as setup and lower amp draw, a 36mm motor would be good running on 4s. Apply the typical setups for the Blackjack26. There are lots of affordable motors out there for this size. Also, the UL1 power plant would be a good choice for a model like this. Both the original Blackjack 26 and the UL1 employed 6-pole motors which, because of their torque, pulled less amps.

Yes I can shoot some more photos of the underside steps and transom, no problem.

I have a 3650 1500kv ProBoat motor, but planning to start off using a Turnigy 2860 2750kv on 3S. I'll play around with props on the this set up 2 and 3 bladed.

[studioRS]

Man that is a killer little CAT !!
and not that bad of a price

I might have to get one to go with my DF23
and maybe try a sweet heli 3300kv outrunner on 4s with a small prop

Yes, it is very nice for the price. Sweet little hull, just waiting to buy some more Systems Three epoxy so I can reinforce and ready to run.

[Agitator]

All you need to cut kevlar/CF/ Fiskars 9 Inch Premier Titanium Nitride Shop Shears. Got mine at Home Depot $15.00