Finishing a JAE FE in a hurry!

[Tim Strange]

I am trying to get a JAE FE finished in time for a race that my club is hosting in Mt Vernon IL next weekend. I finally have the last piece of the tub glued to the top, the ski is built and has one coat of Epoxy, and the sponsons are finished with one coat of Epoxy on three sides...I am hoping to get two coats on everything and worry about painting later.

I still need to fit the stuffing tube and mount the motor...hopefully tomorrow.

Some quick questions:

1) I have the Zipkit rudder...How high or deep should I mount it?

2) I have a HS-225MG that I plan to mount, but I also have one of the new digital metal gear Hitec waterproof servos. It is closer to a standard size servo and twice the weight (about 2oz) of the 225MG. Is this too heavy?

3) What is the best location for the water exit?

and 4) I have the Aquacraft motor and 60 Amp speed control along with a pair of Zippy 4S 5000mAh 45C lipos...I believe the course should be a 1/6 mile oval. Can someone recommend a safe heat racing prop?

I appreciate any help and suggestions...cutting this one to the wire! The earliest that I think this boat will hit the water will be Thursday before the race, so there won't be much time for testing.

 

[57fairlane500]

1). Put the rudder as low as you can. The bracket flush with the bottom of the transom.

2). The 225MG will be plenty of servo. It's what I (and several others) are using in both my FE and nitro boats with no problems.

3). Try to put the exit where you can see the water coming out as you drive the boat past you, other than that, it doesn't matter where you put it.

4). You will need to try different props to see what works best on your boat. A H-5, H-7 or 1450 is a good place to start, but we have found that each boat will be a little different. I can pull a 1916, but that is not a good place to start. You will want to collect data as you go on things like motor/speedo/battery temps. Also log how much you are putting back in to the batteries each time you charge them (after they cool off). A normal heat should have you putting back around 2100-2300mh from what I am seeing with similar batteries.

 

[Tim Strange]

I do have a Zip mod 1450 I suppose that it should be OK to start with.

I made some progress yesterday during my free time at work yesterday, but of course I left my drill at home so I couldn't get the rudder and strut mounted

Does anyone have any tricks for drilling the holes for the Zip motor mount?

 

[lohring]

We started running the ABC H-10 with the Aquacraft speed control. A lower resistance, higher amp speed control allows props like an ABC S-15.

Lohring Miller

 

[Tim Strange]

I am looking into getting a 120 AMP ESC in the future...kind of like the new Hifei Swordfish 120 with Data Logging. Looks like I have to order some ABC props also. For now, I want to stick with something safe so I don't smoke the motor, ESC or batteries...and also hoping that I had something on hand that would work. I have several Octura 20 size props on hand, but it looks like the mod 1450 is my best bet. I have a few Grimracer props (one of which I think is an ABC H-4?) and the CNC 1450 from Zipkits.

Anyway, I put a coat of Epoxy on the tub and another on the ski and sponsons. The parts are baking in the sun right now...100+ degree heat should speed the curing time of the West Systems Epoxy!

Still looking for some tips on getting those motor mount holes drilled....

 

[Jeff Schindler]

Tim, if you need a cooling jacket, ive got 2 in stock

http://www.amainhobbies.com/product_info.php/cPath/4_1631_1894_1909/products_id/207641/n/AquaCraft-36mm-One-Piece-Machined-Motor-Water-Jacket-w-Fittings

 

[gil sonsino]

Tim the best way to drill holes for the motor mount is using a right angle coupled to a dremel.As you have the motor aligned with the stuffing box make some marks using a piece of steel or whatever you have and then you will be able to finish this task. Gill

 

[Tim Strange]

Thanks Gil, that is what I was thinking. I picked up a set of the Dremel drill bits (already have the 90* attachment)...was thinking it might be a bit too long. I will be able to size it up in a few hours once the last coat of epoxy cures.

I will do as you said...position the motor and mount to the stuffing tube and make the marks. I think that I will then remove the motor from the mount and reposition the mount to the marks and insert one screw until it just crushes into the wood to make a mark. Then drill that hole and remount the motor and check for proper fitment...then do the rest.

Jeff, I have the OSE cooling jacket, but if I run into clearance issues I may just give Honest Jeff's Hobbies a call to see of that mount will work...

 

[Tim Strange]

Just tried the Dremel 90* attachment...and it will not even fit without a bit. So I made the marks for the holes by screwing the bolts from the inside until they compressed the wood a bit. Then I used a caliper to find where to drill the hole from the outside. The first hole was spot on...the second was about 1/16 off.

 

[bzubee]

For the holes Gene Taylor and Bill McGraw showed me a trick use a nail heated red hot and burn a hole through where you need it. Also when mounting the rudder don't for get to leave clearance for the mouning nuts and washers on the inside of the bait box! Does no good to mount real low if there is no clearance for the mounting hardware.

 

[gil sonsino]

Tim I forgot to say that I use a short drill to make theses holes with the 90 attach...you can find them in many depot stores.Gill

 

[Tim Strange]

I managed to get all of the holes drilled and everything bolted up. I also got the stuffing tube aligned and epoxied in place. I'll just need to take it back apart and seal the holes and attach the ski. So it is getting there...

One problem I just noticed is that I have the wrong motor mount. It looks like I have the outrunner version with the smaller hole. The motor mounts up fine, but the collet will not fit all the way on the shaft. Also I cant use a thrust bearing (which i should have) although I am not really sure it is necessary.

Does anyone know the diameter of the center (shaft) hole for the Zip inrunner mount? I assume that is the only difference between the two...

 

[Doug Smock]

13mm.

 

[Tim Strange]

Not sure that I have a 13mm drill bit...or can even find one locally. Is the hole stepped for the thrust bearing or is it just big enough to give clearance for the bearing?

I may just have to drill the hole out enough to get clearance for the collet for now.

 

[gil sonsino]

Tim yes this hole is for the thrust bearing..Gill

 

[Tim Strange]

Thanks Gil...I was actually wondering if there was a "seat" that the thrust bearing rides in. I looked at the picture on the Zip Kit web site and didn't see one. I have a stepped drill bit that created a perfect 13mm hole.

The ski has been epoxied on and another coat of epoxy applied to the insides of the sponsons and box lid. Hopefully tomorrow I can get everything remounted and also get the sponsons attached. I suppose the only thing holding me back from a maiden on Thursday is if I somehow manage to screw up the flex shaft when I cut it.

Speaking of the flex shaft...I have the .150 shaft. Would it be wise to move up to a 3/16 shaft in the future?

Also...I used 1/4" brass for the stuffing tube, and there is quite a bit of room around the .150 cable. Is it a good or bad idea to make an insert to place inside the stuffing tube?

 

[jayt]

As long as you use the limitied motors, the 0.150" cable is fine (just use quality cable like Hughey). That stuffing tube is too large, go one size smaller. The 1/4" is perfect for the 0.187" cable but really has too much clearance for the smaller driveline. BTW there in nothing wrong with using the larger cable with limited power, the increase in drag is not noticeable - or it wasn't when I upgraded mine in two different Limited motor models.

.

 

[gil sonsino]

Tim if you ittend to use the .150 flexshaft keep with the 3/16 brass stuffing box as the 1/4"has too much clearance and may let water enter the boat but as said I see no issues to stay with the 3/16 cable even for this class motor.Gill

 

[Tim Strange]

Thanks guys...I have already installed a 1/4" stuffing tube and I am stuck with the .150 cable since I only have a .150 collet. I may move up to the .186 in the future.

 

[RodneyPierce]

Tim, just snake a 3/16 brass tube up inside the 1/4 inch. It should slide right in there. Might be a bit of a tight fit, but nothing that a little sanding wont take care of.