JAE Gas rigger - strut question.

[CapeTown73]

I would appreciate some comment from Rod G. Or Joe Petro regarding the ‘Z’-strut on my JAE gas rigger. I have annealed and bent the stuffing tube and I’m at the point of bolting the strut to the transom. I then noticed that the surface of the strut that sits against the transom is not 90* square to the bottom of the strut. (See attached photo). With the transom sitting correctly at 90* up-right to the bottom of the tub, the strut will then be pointing the stuffing tube (and the prop), very slightly downwards (negative) by a degree or two. (See second photo.)

Is this ‘built-in’ negative drive-angle intentional and correct ? If not, I could have the strut surface that faces the transom, re-milled to be 90* square to the hole in the strut through which the stuffing-tube runs. This would result in flat, directly rearward drive for the prop.

 

Thanks in advance for any advice.

 

[Geraghty]

I would appreciate some comment from Rod G. Or Joe Petro regarding the 'Z'-strut on my JAE gas rigger. I have annealed and bent the stuffing tube and I'm at the point of bolting the strut to the transom. I then noticed that the surface of the strut that sits against the transom is not 90* square to the bottom of the strut. (See attached photo). With the transom sitting correctly at 90* up-right to the bottom of the tub, the strut will then be pointing the stuffing tube (and the prop), very slightly downwards (negative) by a degree or two. (See second photo.)

Is this 'built-in' negative drive-angle intentional and correct ? If not, I could have the strut surface that faces the transom, re-milled to be 90* square to the hole in the strut through which the stuffing-tube runs. This would result in flat, directly rearward drive for the prop.

 

Thanks in advance for any advice.

The 1.5 degree negative in the Zippkits strut is exactly the way Joe had them built.......The negative in the strut was the result of feedback from Kentley Porter when he tested the boat and set the new IMPBA [2] lap records.

As far as I know the JAE team has never run the 1.5 degree negative strut.With all the boats out there being run with that Zippkits strut there has not been any negative feedback......It has been pretty obvious to us that boat is not in the least bit sensitive to either strut............

The only questions we have had about the strut has been when the instructions were not followed and the strut was raised up off the ski bottom sheeting by the boat builder......

The major consideration is having the strut as low as possible on top of the ski sheeting....the closer the bottom of the strut is to the bottom of the ski sheeting the better....

 

[CapeTown73]

I would appreciate some comment from Rod G. Or Joe Petro regarding the 'Z'-strut on my JAE gas rigger. I have annealed and bent the stuffing tube and I'm at the point of bolting the strut to the transom. I then noticed that the surface of the strut that sits against the transom is not 90* square to the bottom of the strut. (See attached photo). With the transom sitting correctly at 90* up-right to the bottom of the tub, the strut will then be pointing the stuffing tube (and the prop), very slightly downwards (negative) by a degree or two. (See second photo.)

Is this 'built-in' negative drive-angle intentional and correct ? If not, I could have the strut surface that faces the transom, re-milled to be 90* square to the hole in the strut through which the stuffing-tube runs. This would result in flat, directly rearward drive for the prop.

 

Thanks in advance for any advice.

The 1.5 degree negative in the Zippkits strut is exactly the way Joe had them built.......The negative in the strut was the result of feedback from Kentley Porter when he tested the boat and set the new IMPBA [2] lap records.

As far as I know the JAE team has never run the 1.5 degree negative strut.With all the boats out there being run with that Zippkits strut there has not been any negative feedback......It has been pretty obvious to us that boat is not in the least bit sensitive to either strut............

The only questions we have had about the strut has been when the instructions were not followed and the strut was raised up off the ski bottom sheeting by the boat builder......

The major consideration is having the strut as low as possible on top of the ski sheeting....the closer the bottom of the strut is to the bottom of the ski sheeting the better....

Thanks Rod, You have put my mind at ease and I can now go to bed. (It's just gone 11:00 PM here ! )I will proceed with the boat tomorrow and I am really enjoying the build ! I'm hoping to start with the paintwork early next week and I'll post some photos towards the end of next week. I"m still enjoying my JAE.21 and we now have three of them running at respectable speeds. The first raceday of our new season is on the 14th of this month. Cant wait.

Kind regards,

Wennie.

 

[Hesco Racing]

Wennie,

The other question you also should have asked is the problem we had with the nitro z strut in that the mounting face of the z-drive was not square due to the taper blow out you get from the laser (I asume they are laser cut)cutting, which caused the strut once mounted to to not be parallel with the running of the boat. Is that also normal?

Cobus