Ski Tow Assembly

[Toolman]

I’m designing a couple of Ski Tow assemblies for a couple of Connolly’s. The customer wanted a main spool up on top of the pole and then what we call a mini spool that’s gonna ride down low on top of the hull to give different recreational ski people different pulling angles. I will post this part by part.

 

[Toolman]

The Lower Mount.
The lower amount is made from aluminum and has an angle on it that matches the transom angle. It is also notched to clear the quarter inch aluminum plate that runs across the inside of the transom. The two counter bored holes are for bolts that will go directly into the center transom block. You’ll also see a 3/8 hole drilled through the side of the mount that goes through the pole and secures it. You also see two small 3/8 threaded holes that will hold some kind of a plate that is for a valve or a switch or something, I’m not sure. We also 3-D printed the part before I started machining to be sure everything fit.

 

[J DUNN]

I had the same on my Hallett 240. I'll try to find the pic. For the lower angle I bought a Stainless Collar from McMaster and had it polished then bolted it on.

EDIT: Added pics. Oh my goodness, you just made me want my boat back.........
I look forward to seeing how your project turns out, please keep posting progress pics. I wish I knew how to machine like that.

 

[Toolman]

The Spool.
I made three spools that are out of stainless. Two are for the Connolly’s and one is for another customer which has a different size pole. I used a small piece of one of the poles as a gauge for boring out the holes. So I machine an arbor that has a different size on each end to hold the part in the CNC lathe.

 

[Toolman]

The Pole.
The poles are heavy wall stainless steel tubing. The bottom of the pole just gets a 3/8 hole drilled through it that goes into the lower mount. The top of the pole has to be plugged, drilled, and tapped to hold the spool.

 

[Toolman]

Mini Spool.
The mini spools were made from the same material as the big spool. Processes were the same but instead of a socket head cap screw holding it on, I bored the center out to be a slip it over the pole. I also drilled and tapped an 8-32 hole discreetly into the part to keep it from rattling on the pole. I use the same arbor as I did for the big spools.

 

[Toolman]

Collet Support ( or you can call it a back up plate) if needed.
Just a quick little plate that if needed will sandwich the hull between it and the Collett and the bezel. I drilled the holes way oversize and I punched out the main bore way oversize because all it is to do is to draw everything together and the looser it is the better the holes will lineup when drilled through the hull. One of the Connolly’s has a 2 x 4 glassed in under the hull which we will be using stainless steel wood screws and these back up plates will not be needed. The other Connolly does not have a 2 x 4 glass in under the hull and will probably have to use flathead machine screws and the backup plate.

 

[Toolman]

The Collet.
The Collett is made from delrin. The purpose of the collet is to take up the gap between the hull and the pole. The collet will take the load when the pole is pulled on and there is no metal touching the hull or the bezel. So the bottom of the Collet is long and goes down into the hull half an inch. The top of the Collet only sticks up an eighth of an inch and protrudes through the bezel to take up the The gap and give it a nice look and the bezel will secure it.
I got me a big piece of delrin then bored and chopped off two blanks. Then I machined another arbor with a cap to hold it while I manually machine it.

 

[Toolman]

The Bezel and finish the collet.
I bored and turned the ID and OD of the bezel two parts deep. Made sure it fit the delrin Collet with a slip fit. Then it went on to the mill to drill the three hole pattern two parts deep. Then back on the lathe to machine the counterbore that’s going to swallow the collet. I part off the first bezel and then repeat the process for the second bezel. Then I machined another arbor to hold the bezel for drilling and for the 45° Chamfer. Now the collet goes onto the mill for the three hole pattern. The top of the hull only had a flat of so wide and I had to shrink the bezel and the collet to fit. That made the counter sinks for the number 10 set stainless wood screws too small. So I machined down the heads of the screws to fit. After machining down the screws it rolled burrs into the Phillips slot. So I took a de-burr knife and scraped out the burrs. Then I took an oversized Phillips bit and pounded it into the slot to reform it. I gave the customer extra screws just in case they lose any. You can see in the picture the screw before and after machining the heads down.

 

[Toolman]

Job…………..DONE

 

[HNL2LHC]

Impressive!!! Thanks for sharing

 

[lenmann]

Damn! Clever engineering and beautiful machine work.

Well done sir.

 

[mattyc]

Bad ass! Good looking work and cool planning. How much time do you have in these?
@Toolman

 

[Echo Lodge]

Can't believe all the thought and work that went into that! Incredible work. I bought something similar for my roll bar boat years ago. But nothing compared to what you made!

 

[Meaney77]

Its crazy the amount of time that goes into making something like this. Looks so simple to do until you see the amount of detail and thinking to get the finished product.

 

[Toolman]

Bad ass! Good looking work and cool planning. How much time do you have in these?
@Toolman

Around 40 hrs including computer time.

 

[boatnam2]

Not sure if your making it for yourself or to market but one thing I see people wanting with older boats with the extended ski poles is a mount for them with a board holder or rack if you will.

 

[mattyc]

Around 40 hrs including computer time.

Sent you a pm

 

[Toolman]

Bonus pics.
In the first pic you can see where I discreetly put the 8-32 set screw hole. it’s kinda hard to see it on the bottom land with all the reflection. You can also see where the fuel valve bolted to the lower aluminum mount.

 

[Melloyellovector]

Now make the same set up with bravo drive base plate that attaches to the bolts on top of inside transom assy

looks great btw

 

[Toolman]

Now make the same set up with bravo drive base plate that attaches to the bolts on top of inside transom assy

looks great btw View attachment 1269280 View attachment 1269281

I see two small bolts at the top of that bravo unit that could be utilized. Just saying

 

[Melloyellovector]

I see two small bolts at the top of that bravo unit that could be utilized. Just saying

Ya, my original one had to be cut off to remove transom
steel and aluminum deal. At the time I figured ehhh someone makes it. Come to find out, no they don’t. Lol

i can get better pics and measurements if it’s something you think would be pretty simple.

My hold up previously was that I have lines that were routed under the transom rail where ski tow goes thru. How ever since pulling motor for new we could re route if needed.
I was considering having Racey do an external transom mount tow.

PM what ski tow cost would be , plus what you think it would be roughly for adapter to drive bolts

 

[Toolman]

Now that I look at it more I think you could bolt a bracket right down on top of the bravo unit and drill a couple holes through it and bolt it up from underneath.

 

[Melloyellovector]

Now that I look at it more I think you could bolt a bracket right down on top of the bravo unit and drill a couple holes through it and bolt it up from underneath.

I’ll take some measurements next weekend to havasu and pics.

 

[mattyc]

Bonus pics.
In the first pic you can see where I discreetly put the 8-32 set screw hole. it’s kinda hard to see it on the bottom land with all the reflection. You can also see where the fuel valve bolted to the lower aluminum mount.

View attachment 1269232 View attachment 1269233 View attachment 1269234 View attachment 1269235 View attachment 1269236 View attachment 1269237

That turned out really nice. I had to go back and read it again and look at the pictures closer because there were a couple things I missed or didn't understand the first time through. Thanks for sharing!

 

[Jay Dub]

The Pole.
The poles are heavy wall stainless steel tubing. The bottom of the pole just gets a 3/8 hole drilled through it that goes into the lower mount. The top of the pole has to be plugged, drilled, and tapped to hold the spool.
View attachment 1268207 View attachment 1268208 View attachment 1268209 View attachment 1268210 View attachment 1268211

this is very cool. Thank you for sharing

 

[Racey]

Ya, my original one had to be cut off to remove transom
steel and aluminum deal. At the time I figured ehhh someone makes it. Come to find out, no they don’t. Lol

i can get better pics and measurements if it’s something you think would be pretty simple.

My hold up previously was that I have lines that were routed under the transom rail where ski tow goes thru. How ever since pulling motor for new we could re route if needed.
I was considering having Racey do an external transom mount tow.

PM what ski tow cost would be , plus what you think it would be roughly for adapter to drive bolts

I've done a couple like this for Bravo setups. This one i did a couple years ago.

Pretty simple, usually end up having to cut an angle where the pole base meets the bracket, but it's very shallow.

 

[Toolman]

I've done a couple like this for Bravo setups. This one i did a couple years ago.

View attachment 1270758




View attachment 1270759

Pretty simple, usually end up having to cut an angle where the pole base meets the bracket, but it's very shallow.

Yes, the Connnolly guys had to decide if they wanted it in line with the transom angle or perpendicular to the top of the hull. They went with perpendicular. But that’s a nice little bezel. And the way you mounted it to the outdrive is pretty much the simplest way to do it.

 

[Hammer]

Now make the same set up with bravo drive base plate that attaches to the bolts on top of inside transom assy

looks great btw View attachment 1269280 View attachment 1269281

I need one too Tim! I’m gonna need a ski pole on the quick for the vector now that both kids are skiing.

 

[ltbaney1]

Very nice work.

 

[classicvdrives]

The ski tow worked great!

 

[mattyc]

View attachment 1271465
The ski tow worked great!

Looks great, goes perfect with your boat.
What lake is that?

 

[classicvdrives]

Lake Nacimiento, CA

Looks great, goes perfect with your boat.
What lake is that?

 

[Backlash]

View attachment 1271465
The ski tow worked great!

Damn that's BEAUTIFUL!!! I love the way that turned out!!! I may need one too someday, but taller to clear an outboard. Beautiful work!!

 

[River Dirt 2]