Scratch Build - 29" Balsa Stepped Cat
#101
Spraying the thin CA will take your breath away literally, so spray it outdoors. After applying your thin fiberglass cloth with 3M spray tack adhesive spray on the CA using your paint sprayer much like paint (CLEAN GUN WITH ACETONE AFTERWARDS). The capillary action of the superglue with make boats surface very hard so make sure surface is smooth because it will be hard to sand afterwards. Fill, prime, sand, then paint.
#102
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From: Centerville,
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An up date: Armor plating is complete. The boat is ready for water proofing and then hardware. The rudder is going to run deep, and I think she'll like that. Any one know a good place to pick up some steering rod and bellows? I need to do this right as I expect the bellows to be 1/2 submerged when the boat is idle. I have the servo and reciever and will order the motor soon, and the SC when I get back from china.
#103
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From: Centerville,
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Stopped by the UPS store today with the hull. It's 476 grams (just over a pound). It will be intresting how much weight the urithane will add. Funny thing: It was breazy out when I went in there and the wind came close to twisting it out of my hand I'm not too upset with the weight. I have a feeling the SV will doing some recovery duty.
#104
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From: Centerville,
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How big of a difference would i see between other wise identical setups between an 8XL and a 9XL. Looks like a 200rpm/volt difference, what else can I expect? I can get the 9XL for about 20 bucks cheaper.
#106
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From: Centerville,
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No probably not. I'm thinking of making the jump to Lithium with this boat. I may run it on 12 cells for some testing but Lipo is the future. Why do you ask? 9XL going to hurt the Nimh batts for some reason? Saw OC's old mean machine doing 55mph with a 12XL so I'm a bit scared as to what I'm going to end up with here. [:-]
#107
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From: Montgomery, AL
Ok, so I'm soooooo going to ask a noobie question.
I got a copy of the originals for this boat (the original shockerman plans). They're in PDF. I have access to a plotter at work... how did you get them to print full size?
I got a copy of the originals for this boat (the original shockerman plans). They're in PDF. I have access to a plotter at work... how did you get them to print full size?
#108
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From: Adelaide, AUSTRALIA
Set your page size to A0 and send it to the plotter. It works for me with our plotter. If you forget to reset the page size it comes out A4 though.
#110
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From: Centerville,
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I have a plotter at work too. I took the 8.5 x 11 to kinkos and had them upsize it until I was happy. Cost me $0.80. Then I physically modded the cross beams with scisors and glue. I know I'm slow but I am working on it.
#111
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From: Montgomery, AL
I started the build last night. This is my first 100% scratch build and I've already got a second build planned (1/10th crackerbox).
I'm learning a LOT very quickly a/b how and how not to cut balsa. Any tips?
I'd love to find a scratch builder tutorial/primer out there.... too many little nuances...
I'm learning a LOT very quickly a/b how and how not to cut balsa. Any tips?
I'd love to find a scratch builder tutorial/primer out there.... too many little nuances...
#112
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From: STARID
I use a scroll saw for cutting all the wood I use for boats. Works perfect. A little tip on cutting out your parts...I always cut a little oversize and sand the rest. Then, if there is a matching peice, clamp together and sand until it is the same.
#113
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From: Centerville,
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I probaby didn't do it the easiest way. I printed the drawings to size. I taped all the parts down and used a needle to make a dotted line to show me where to cut. Removed the prints and cut everything with a modelers knife. Like Jdoug said, cut oversizded and sand. Balsa sands very quickly with 220. I glued the whole frame together and then sanded all the intersections until everything was even. Another tip is to sand the angle on the stringers especially up front. I used alot of CA. I bought an oz of great planes Medium (any thiner and it will run too much). Anyway I had to get more. I'd take your time and finish this one before you start the next. You'll learnd soo much on the first one and the second will be better as a result. Later
#114
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From: Montgomery, AL
Yeah, I did it the hard way as well. I glued them to my balsa then cut them out with a dremmel.
I have started the skinning and will post some pics soon.
I think (not sure) that I'm going to put glass or carbon on it instead of ply.... carbon would look coolest
I have started the skinning and will post some pics soon.
I think (not sure) that I'm going to put glass or carbon on it instead of ply.... carbon would look coolest
#116
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From: Centerville,
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Wow I can't believe how far this has slipped down! I'm really slow. I have some new pics but progress is slow due to time and finances being absorbed elsewhere. Hull will float and I mounted the outboard hardware yesterday after some modifications to make it fit properly. I'm assuming that being able to move the cetner of the prop shaft one half of a diameter above the bottom of the lowest point of the hull to 1/2 a diameter below would be enough adjustment for any post build tuning I would need to do (I actually have about double that). Is this true? Also I'm ready to put the steering servo in. Where's a good place to get the linkage and boots to go though the transom. I'd like to find a good variety to pick from as this might be kind of non standard. Or is there any common material in HW stores that I'm not thinking of that make good linkage material? I don't want to use a bent up paperclip but I'm willing to fab up something creative if it makes sense and looks/work well. I'll post the latest pics soon.
#117
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From: Centerville,
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Still hoping for some recomendation for steering linking and such. Not a subject that gets much information around here. Here are the most recent photos.
#118
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From: Centerville,
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still not a subject that gets much attention. Anyone. Steering linkage. I suppose you can use auto linkage if it's long enough.
#119
Scott, I don't quite understand what you are wanting to know. For steering you use a pushrod with a clevis on each end as with any other boat.
Ryan
Ryan
#120
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From: Centerville,
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Yea. Sorry but I haven't been able to find much of a selection anywhere. Considering I don't really know what I need I'd like to find some cheap and buy a few. Boots too. I'd expect to see a bunch on OSE but I didn't see much of anything. First time I've ever seen the word clevis on this site.
#121
What I have done in the past is used some brass tubing larger than the pushrod and teflon diameter. This gave me room to mount the pushrod seal on to. Then the pushrod is cut to size. I like to use a metal Clevis on the servo end and an adjustable threaded Clevis, plastic to avoid metal on metal on the steering arm. In some cases I use E Z connectors to allow quicker adjustments to allow the servo to be in the proper position.
A serach on Tower Hobbies using the words clevis and EZ connectors sometimes called screw lock connectors should give you tons of results.
Ryan
A serach on Tower Hobbies using the words clevis and EZ connectors sometimes called screw lock connectors should give you tons of results.
Ryan
#123
ORIGINAL: SV27dayton
That's what I needed. Thanks.
That's what I needed. Thanks.
#124
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From: Milton,
ON, CANADA
Nice build dude [sm=thumbup.gif] That hardware is very nice too since its a copy of H&M stuff. Johnny will treat you right he always does for me
.
Keep going, any paint yet?
.Keep going, any paint yet?
#125
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From: Centerville,
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Thanks,
The photos in post 117 it has 3 coats of waterbased urathane on it. That's the way it's staying for now. I want people to know its wood. I may put some graphics on it some day to dress it up but for now the exterior is complete less the canopy which is not necessary for testing. Yea the hardware is nice. I just hope it's reliable. I should probably order a few more cables from him.
The photos in post 117 it has 3 coats of waterbased urathane on it. That's the way it's staying for now. I want people to know its wood. I may put some graphics on it some day to dress it up but for now the exterior is complete less the canopy which is not necessary for testing. Yea the hardware is nice. I just hope it's reliable. I should probably order a few more cables from him.



