Making a trim nozzle

[Havari]

I'm considering getting a trim/tilt nozzle for my Colorado that currently has a 7 series nozzle on it. I've had a look at a couple of tilts & at face value they don't seem much more than a gimbal around the nozzle housing providing the second axis of movement. Does anyone know if its viable to make a stainless gimbal & machine the inside of the current nozzle a bit to turn it into a tilt nozzle...or even done it?
Cheers

[steely]

yep I and plenty of other people have done it, if you have access to a lathe ect its easy as, just remember to machine in some nylon bushes or it will be a and potentially be dangerous

[Havari]

Thanks Steely! Might just give it a go. Do you have any photos of the one you did? Cheers

[Karl]

Here is one that was converted

[sje]

I'm doing one at the moment gotta have it going before the weekend so I can go on the manawatu run. I will put up some pics soon.

 Karl when you turn do you notice the change in tilt as thats exactly how I was going to do it.

[Karl]

With the trim through the centre it does not change.  I outsmarted myself with the first attempt where I copied the jetski T3 type setup with the steering and trim from the same side didn't work as the trim did change with steering.

[sje]

Havari, first I measured the size ring I would need which was determined by the distance between the existing steering pivots. This worked out to be 170mm. I was going to roll a bit of flat bar to that size but went to my friendly hydraulink agent across the road and in their scrap pile was a short bit of 170mm hyd tube. Looking at karls this is way over the top as it was 1/2 inch thick but its a start. I set it up in my 4 chuck and machined the OD till it came true (hyd tube is true on the ID) from that I used the 4 jaws to scribe a line which gave me 90 deg points as I dont have a degree wheel or any other way of getting it accurate. Then as luck would have it the resulting ring, with the help of a hack saw blade for a spacer, fitted in the tool post and I was able to drill holes in the ring to suit. The pivot holes are 5/8 and the tilt ones will be 3/4 cause they take a nylon bush. That way I can use the existing steering arm and pivots and if it does not work its easy to revert to the previous steering. I willl do the tilt section and post pics tomorrow. So far its cost nothin but a couple of hours.

[Havari]

Great pics Karl & sje...thanks heaps for posting the pics...nozzle looks real good Might just give it a go

[sje]

Havari, give it a go, the changes I have made dont change the actual workings so I can go back to the original if needed. I didnt need a tilt nozzel just thought it might be a bit of fun.

The next step following on, was to get the tilt sorted. I put  a bolt (a bit of rod or anything will do) thru the steering pivots but also long enough to pick up the actual nozzel. This alowed a couple of things. I was able to check the steering angle was the same left and right with the old and new steering and you get to set the straight ahead position for the gimbal to be the same as the nozzel. It also holds the nozzel center to the housing so the tilt arms can be made. Hope that made sence. 
Next is to hook up a tilt control arm, steering arm etc. Probably the most time consuming part.....

[Karl]

SJE looks like that tail housing could tell a story or two!
Instead of bushes you can also use spherical bearing.

[sje]

That tail housing can tell a few stories its sunk a few times, had SAR on standby but the repairs are from a fun sprint years ago under the ashurst bridge and taught me that having a unit mounted way out the back and then converting to 3 stage is asking for trouble. I tore it clean off!

[mohawk]

I made my trim ring an octagon and used an arm too operate the trim (like my southern jet noz ).
I did the whole job with stainless arc rods and a 60buck drill press cause that's all I had . It was pretty easy realy and works as well as anything else. Like sje  I put long bolts through the original holes too line up the tilt arm thingys .
The stainless pulls like a schoolboy when you weld it so I welded 4 bits of angle iron to a big steel plate with the holes for the pivot points drilled in them , then bolted the pieces for the trim ring to them and welded it . . It realy made lining everything up easy.
http://www.nzjetboating.com/yabbse/index.php?action=dlattach;topic=24760.0;attach=49326;image