JAE TWIN PLANS !!!!!!!!!!!!!

[Michael Costanzo]

I think some of the Flex in the fin is actually the booms flexing

RG said some where that most guys had gone to solid boom tubes

i run fiberglass thick wall/hollow boom tubes and there are on my 90/101 and they are just fine. like doc turner was saying, there is much more testing needed to get the bigger boats in top form for heat racing.i am in the proccess of that right now along with different turnfins. one way ore the other it will get fixed.the boat has a great deal of potential and it is going to take time.and when it does happen, things are really going to get fun!! i am so glad rod and all the others have put some kick in the pants and made it a little more easier and cheaper for guys to get into riggers.mikie.

 

[dr gary turner]

Are the fins braced to the tub?

Yes we tried that. Mark made a neat adjusting rod. I hit a bouey and it broke. Helped some. I will post pictures of the boat. Fast 83-85 mph is pretty easy to get on the timing lights. When I raced it it would not finish. Tripped and rolled about the 3rd lap of the heat on bouey 5&6.

 

[dr gary turner]

Here is my 101 JAE. If some one developes a turn fin let me know. I do think a rudder blade 1.5 inches wide would help. Had incredible results on another 101 hydro. Also tried it on Marks twin with improvement in turning.

The first picture is the 1.5 rudder blade. Also the ramp should not be more than 2 or 2.5 deg. More than 2.5 is TOO much.

 

[Michael Costanzo]

Here is my 101 JAE. If some one developes a turn fin let me know. I do think a rudder blade 1.5 inches wide would help. Had incredible results on another 101 hydro. Also tried it on Marks twin with improvement in turning.

The first picture is the 1.5 rudder blade. Also the ramp should not be more than 2 or 2.5 deg. More than 2.5 is TOO much.

hi doc, boat looks really nice. i run a acu-tech blade and it works fine.i hopefully am going to come up with a few blades soon.my boat hadldes like a slot car by itself,and hooks/trips/unhooks...what ever you what to call it in heat racing.cannot wait until its fixed.going to be a whole new ball game!mikie.

 

[mtruex]

Here is my 101 JAE. If some one developes a turn fin let me know. I do think a rudder blade 1.5 inches wide would help. Had incredible results on another 101 hydro. Also tried it on Marks twin with improvement in turning.

The first picture is the 1.5 rudder blade. Also the ramp should not be more than 2 or 2.5 deg. More than 2.5 is TOO much.

.
Doc,

Again, fin is too small and too far forward , strut and rudder are too close to transom and sponsons are too close together. You are right on your ski angle at 2 degrees as i told u in huntsville. The front sponsons should be 4 degrees, where are they now?

 

[dr gary turner]

Here is my 101 JAE. If some one developes a turn fin let me know. I do think a rudder blade 1.5 inches wide would help. Had incredible results on another 101 hydro. Also tried it on Marks twin with improvement in turning.

The first picture is the 1.5 rudder blade. Also the ramp should not be more than 2 or 2.5 deg. More than 2.5 is TOO much.

.
Doc,

Again, fin is too small and too far forward , strut and rudder are too close to transom and sponsons are too close together. You are right on your ski angle at 2 degrees as i told u in huntsville. The front sponsons should be 4 degrees, where are they now?

Martin I had the rudder further back and thought it handle better when it is more forward. Generally at least in a conventional hull moving the fin forward makes the boat turn quicker, more sensative. I had it further back towards the transon and built a brace to hold the fin. Bending the fin is a real problem even with tempered steel. I used boom that was made from stips of aluminum and in the middle was delrin which really stiffened it. How far back should the strut be? We actually milled the the bottom of the strut to match the angle of the ramp. What should be the spread of the sponsons?? Again if it gets too wide, bending and flexing of the goom tubes become a proplem.

 

[mtruex]

Doc,

this is not a conventional boat, the fin too far forward will make it darty and turn in too quick but then it will push and not hold the turn, really make it hard to drive..at least that has been my experience and i have also helped others with there boats doing this with the fin too far forward..

ok, leave the rudder where it is, i try to keep the trailing edge of the rudder just ahead of the drive dog but i dont think thats a big deal.. but the front of the strut needs to be at the trailing edge of the ski, there is a picture somewhere that rod drew up.. we figured out very early in testing that if it was up in the ski the boat would be very loose and would not stay hooked up good..trust me its a big deal

on a boat that size i would try to get the sponsons at LEAST 24 inches wide (my 45 is 24inches) and do whatever it takes with boom tubes to keep them from flexing too much, another reason to mount them solid in the hull without small delrin adjuster blocks, and the very reason i use solid rods, as hollow tubes would have to be very large OD..

you may need to make a new right sponson that is longer and very stiff in the back half to mount the turnfin, and also brace it to the tub, if you find where your boat balances front to rear and mount your fin so the center of pressure lines up with that mark you will be very close on where it should be.. i would lose the shingles also, they are not needed and do some funny things on the 45.

as rod said there hasnt been a lot of testing done with the larger boats, but with that said i would think if you were to have problems with the boat in heat races that it would be on the SAW, because the boats run so light on the water, not in the turns where the fin should lock the boat down.. i know with all my boats if they ever start to get loose near the end of the SAW as soon as i start to turn they are locked down and have never tripped even when its been so rough that i cant run WOT..

i hope this helps and if you have any other questions ask.. i am confident with the boat set up properly you will be amazed but you have to pay attention to the details..these boats are very different than what your used to but very simple once you understand them.. and i am sure that david preusse can make you a turnfin that will work..

 

[Geraghty]

Doc,

Maybe this will help.........On all of the prototypes I have built,nitro and FE ,the relationship between the rudder and the prop has meant absolutely nothing....[and I have had them all over the back of the boat]

likewise how far the prop has been located off the back of the ski and behind the boat has also meant nothing.....However,like Martin said,the strut being down on the ski and parallel with the bottom of the boat is a big deal....

Rod

 

[mtruex]

Rod meant to say you can have the prop too close to the ski but not really too far behind it..

 

[Jim Caldwell]

Anyone tried the Zipp Gas rigger turn fin?

I am using it on 15 lb. 8s rigger that is close to the JAE specs and it works great.

Worth a try.

 

[dr gary turner]

Doc, Maybe this will help.........On all of the prototypes I have built,nitro and FE ,the relationship between the rudder and the prop has meant absolutely nothing....[and I have had them all over the back of the boat] likewise how far the prop has been located off the back of the ski and behind the boat has also meant nothing.....However,like Martin said,the strut being down on the ski and parallel with the bottom of the boat is a big deal.... Rod

Martin and ROD, Look at my picture of my boat. I have the strut down flat with the ramp. In fact the bottom of the strut is milled to fllow the line of the ramp or angle of the ram. I must be confused becaust Martin thinks the strut is too close to the transom. WE cut the bottom of the ram to get the strut down and then milled the bottom of the strut to follow the angle of the ramp.

Again Rod NO difference the rudder is at???? Martin I thin feels like it is too close. We had all of our rudders 21-101 leading of the rudder behind the drive dog. Being not please we moved them in to where tailing edge was at or in front of the drive dog.

Rod I think that the JAE has been a great development but I guess there needs to be a handbook of directions about many things you and Martin have found. I am going to try and work with my twenty boat. Trying 3 new JAE's last year was a bust. I was going to sell the 101. I may wait till the fin hardware placement details get worked out and then revisit it.

 

[dr gary turner]

Doc, this is not a conventional boat, the fin too far forward will make it darty and turn in too quick but then it will push and not hold the turn, really make it hard to drive..at least that has been my experience and i have also helped others with there boats doing this with the fin too far forward.. ok, leave the rudder where it is, i try to keep the trailing edge of the rudder just ahead of the drive dog but i dont think thats a big deal.. but the front of the strut needs to be at the trailing edge of the ski, there is a picture somewhere that rod drew up.. we figured out very early in testing that if it was up in the ski the boat would be very loose and would not stay hooked up good..trust me its a big deal on a boat that size i would try to get the sponsons at LEAST 24 inches wide (my 45 is 24inches) and do whatever it takes with boom tubes to keep them from flexing too much, another reason to mount them solid in the hull without small delrin adjuster blocks, and the very reason i use solid rods, as hollow tubes would have to be very large OD.. you may need to make a new right sponson that is longer and very stiff in the back half to mount the turnfin, and also brace it to the tub, if you find where your boat balances front to rear and mount your fin so the center of pressure lines up with that mark you will be very close on where it should be.. i would lose the shingles also, they are not needed and do some funny things on the 45. as rod said there hasnt been a lot of testing done with the larger boats, but with that said i would think if you were to have problems with the boat in heat races that it would be on the SAW, because the boats run so light on the water, not in the turns where the fin should lock the boat down.. i know with all my boats if they ever start to get loose near the end of the SAW as soon as i start to turn they are locked down and have never tripped even when its been so rough that i cant run WOT.. i hope this helps and if you have any other questions ask.. i am confident with the boat set up properly you will be amazed but you have to pay attention to the details..these boats are very different than what your used to but very simple once you understand them.. and i am sure that david preusse can make you a turnfin that will work..

Martin Thanks for the advise: I decided yesterday to relook at my 21: My boom tubes flex TOO much and am fixing it. The strut placement: What is 1. the distance of the drive dog from transom? 2.How far does the ramp need to extend beyond the trtansom.3 the front nose of the strut, how far does it go into the ramp. 4. How deep is the rudder below the drive dog. 5.How wide should the rudder be. 6. distance between the inside plates of the front sponsons 7. Number of degress of the bottom of the front sponson......4 deg?. 8. Any toe in in the sposons. 9 I have a turn fin coming hopefully from Prusse, Again placement of the turnfin, middle of the blade where is relationship to the CG.

NOW MY THOUGHTS on why they do not seem to heat race. Last year I saw only one JAE perform well and repeadedly in heat racing and it was guy in the Evansville club. He had ramps or wedges on top of the sponsons to give down force I guess. All other boats including my 3 would not finish a race and not great handling as you pointed out with the 45. I am ignorant about what you do Martin as a profession and so what I am going to say will probably show it. But I bet the setup on your car for qualifying is not the set up for racing with everyone else on the track with all of the drafting

The race water is vary different than running by yourself even on a rough lake. The water gets all tore up even with 21's and there are holes and swirling water that you can't see and the boat dumps or trips. I think the straight sided front sponson are good for records and running in small races but 6 boat heats not good. I think the boat would heat race better with a 20-30 deg chine. in the front sponson side. I was going to build a set but got disinchanted. Last year was not a good racing year except with my 60 hydro that is real bad. So I am going to work with 21 and see what we can do. Martin I appreciate your help and input. Gary

 

[Michael Costanzo]

Anyone tried the Zipp Gas rigger turn fin?

I am using it on 15 lb. 8s rigger that is close to the JAE specs and it works great.

Worth a try.

going to order one this week and see what happens.thanks jim. mike.

 

[Rick Pirrone]

hi all

ive started the twinn (not the jae type though) heres some pictures for you all to look at enjoy

http://www.intlwaters.com/index.php?showtopic=49363

cheers rick

 

[Charles Perdue]

hi all

ive started the twinn (not the jae type though) heres some pictures for you all to look at enjoy

http://www.intlwater...showtopic=49363

cheers rick

Rick, after you add the nose piece, round the outside corners with about a 3/8 inch radius. Blend this into your top to bottom radius. This helps make the boat more stable.

Charles

 

[Rick Pirrone]

hi all

ive started the twinn (not the jae type though) heres some pictures for you all to look at enjoy

http://www.intlwater...showtopic=49363

cheers rick

Rick, after you add the nose piece, round the outside corners with about a 3/8 inch radius. Blend this into your top to bottom radius. This helps make the boat more stable.

Charles

hi charles this is the nose peice i did up today is this what you are meaning ?????

cheers rick