Thursday, April 23, 2009
Here's a handy chart if you want to check the Angle-of-Attack of your riggers running surfaces as in front and rear sponsons and also the strut...
You need a flat set-up board with slots for the turn fin and rudder blade.
Draw up some straight base-lines on the top of the set-up board surface. Make additional lines 40, 50 or 60 mm in front of the base-line(s).
Put the rigger on top of the set-up board and align the trailing edge of the part of your rigger you want to check the A-o-A of to the base-line.
Measure carefully at the 40, 50 or 60 mm "length" the height up to your running surface (bottom of your sponsons etc).
The rear most part of your running surfaces must be flat or the A-o-A angles will not be right. (They need to be flat to make the boat run good also.)
If you for example have measured the strut angle at 40 mm and you get a reading of 0.8 mm you have a negative A-o-A of about 1.15 degrees...
Yes, it can be tricky to measure but U will figure it out... :)
If you want a high-res PDF of the chart to print out you need to mail me. e-mail
Wednesday, April 8, 2009
If you're like me and use prescription glasses then you know the problem of sun glasses... It's expensive to buy special prescription ones and it's even more expensive if you would like them to be polarized.
Now Polaroid® have a relatively new series of so called "Suncovers" that fits over your normal glasses. They are very easy to use and because they are polarized the glare from the water is greatly reduced also. The Suncovers are available at your local eye ware dealer in different frames and different tints. The ones I like the most racing RC boats is tinted brown. I have bought mines at Specsavers here in Sweden and they cost about 425 SEK here with VAT.
Friday, April 3, 2009
Updated in October: "Jack Ass Performance" has been re-named to simply J.A.E Racing and the riggers have also been re-named to JAE (aka "J" boats). Gradually as most of their freebie plans are published here they will also go into production as a kit by ZippKits.com! You can choose to build it from scratch or buy a kit - its all up to you
Wanna find out more about the JAE .12G kit? Klick HERE.
Updated April 23 with a YouTube video of Martin Truex Jr. running a pre-JAP .12 rigger. Its actually (if Im correct) a modified Firefighter .12 rigger with new sponsons and rear prop-support much like the design on the JAP plans here below. Novarossi engine tuned by Rod Geraghty - it runs about 60+ mph in the video.
VIDEO link here.
Another "Freebie" rigger plan - me like! Even though we don't race these here in Scandinavia it's a cool little rigger design.
These .12 plans are the results of a joint venture between Rod Geraghty, David Hall, Ron Zaker Jr. & Martin Truex Jr. This design approach has been built, massaged and tested a great deal... Read the text block and follow the instructions. There are three sheets of drawings. David Hall drew them in Autocad and we transposed them into a PDF format. (Note, I have have added the logo I made for them and smoothened out the S-bend on the stuffing tube in one of the drawings vs. the original pdf files - no design have been altered from my side of course.)
When you get them copy them to a CD or memory USB stick and go to Kinkos or any other printshop that can print drawings and have them printed on  24" x 36" sheets scaled 1:1 = 100%. You will end up with a full set of templates...
Hint: take the template drawing and put clear shipping tape on the front and back of the templates. Cut them out with a scissors and shazaam you will have template to trace onto a sheet of plywood.
The boat will accept most .12 to .18 "car" engines on the market. Like Novarossi, Sirio, Picco or O.S. etc. You don't even need any water-cooled head for them, they have run these with success with only air-cooling from the cut-down car heads. Use a 180 degree header from Associated with part number #2350.
Do note, all info of the JAP .12G hydro is from Rod Geraghty. I (Niklas Edlund) have not built one of these... yet. ;)
If you're interested to build one of these tiny nitro riggers I highly recommend you to sign up so you can check out the build thread at International Waters forums. ALL feedback and info will be posted there. CLICK HERE.
Click HERE if you want to download the main template PDF drawing.
Click HERE if you want to download the second PDF file of the JAP .12G.
Click HERE to download the basic instruction notes and drawings of the engine mount and rudder bracket etc.
HERE for a pdf of the turn-fin.
Solinger R/C Boat Hardware have also made a combo set of motormounts and rudder assembly for the JAP .12G hydro for $30. Note, Solinger R/C Boat Hardware company doesn't exist any longer...
Joe Solinger: This is the motor mount for the JAP12G, or any boat you wish to use it in. To mount it in the hull you first bolt the halves to the motor. With the wood mounting blocks glued to the hull, set the motor with mounts attached in the hull and locate on the wood mounting blocks to your liking. Use a pencil or some thing to transfer the bolt hole locations onto the mounting blocks. Then remove the motor and mounts and drill the mounting blocks with a 1/16" drill to about 1/2" deep. This is to help keep the wood from splitting. A washer goes on the bottom, then the motor mount and then another washer and the screw goes through the whole stack. For now, just lightly snug the screws. When I'm done adjusting and I know I don't need to take the mount out again I remove the screws and put a drop or two of epoxy down the hole before driving the screw in. This epoxy will soak into the wood and harden the threads as well as hold the screw. So "Just snug" the screws into place. These screws will come out again but its much tougher, they won't come out on their own.
The motor mount system is originally designed by David Hall.
This is the soon to be ready JAP .12G rudder assembly from Solinger.
Rod's simple build jig of the JAP .12G tub.
Detail shot of Rod's JAP .12G build.
If you have already forgot it I remind you to sign up to International Waters community forum so you can get more build tips etc. Click HERE and sign up.
Building is fun! :)