Built this thing today and can’t wait to use it! 
 

You'll probably want to cover the 'bunk' pieces with some insulation or something to keep your boat from moving on you.  It looks like you have locknuts on the wheel (without them, a lot of times the wheel will rub against the nut and cause them to back out), so you're set.  You just saved yourself $100 for what you'd have in a C-tug.

Looks good man. I just built one too.

 

I took the kayak and cart for a hot lap over some rough terrain on our property to try and break it and I learned a thing or two.

 

Glue the runner pieces the yak sits on to the T connectors, if you haven't already. I have pads on mine (pipe insulation) and when I dragged the cart around hard those pieces would pull out of the Ts. I also put caps on the ends to hold the foam on.

 

I opted for the thinner padding rather than using big fat pool noodles. I wanted the yak to actually touch the Ts a little since that is the strongest point...not the ends of the arms.

 

A kickstand is helpful. A strap is pretty much necessary too. I had my kayak doing jumps over tire ruts and it held up. Like I said I tried to mess it up LOL.

 

I used 5/8 copper pipe (no aluminum available locally) for the axle instead of threaded rod. I use clips to hold the wheels on so they can be removed without tools. The cart fits in my front hatch when taken apart.

 

The whole lower frame is glued for strength. The runners clip onto the bottom frame so they can be removed and won't pivot too far. I spray painted it all white.

 

I didn't think it would be as strong as it is. Pretty much the same as yours except for the pads and kickstand. I built it to fit my Ride 115.

 

Hope you don't mind a photo. I was gonna start a thread but you beat me to it

 

 

Looks good.Thanks for the picture. I used 1 1/2 pvc with additional 3/4 caps inside the main axle for some added strength. I got a 10 ft future bay yak and a 10 ft plastic pelican style jon boat. It was mainly built to move around the boats in my yard.

13 hours ago, schplurg said:

I used 5/8 copper pipe (no aluminum available locally) for the axle instead of threaded rod.

I'm curious to see how that holds up.  There's not much stress on the axle really, the 'axle housing' is bearing most of the stress except for the part holding on the wheel.  It would definitely make drilling the holes for the cotter pins to hold the wheel on easier.  I used steel round stock for both of mine and had to wheel out my drill press for those.

The copper axle seems to be working fine. I pulled the yak around the property and banged it around. Today I had most of my gear in it and it seems great, but time will tell. I wanted to be able to take it apart without tools.

 

I would have used aluminum but my local HD didn't have any 5/8 in stock. I'm lucky to get what I did right now with the Covid thing going on.

 

The load is concentrated pretty close to each end of the axle near the wheels so I doubt the axle will ever bend. The PVC probably will lol.

 

I like the idea of an extra cap inside for more axle support. The weak point in these designs is the axle cap area. I thought of trying to do something, even fill the axle housing with spray foam, but I haven't done anything. 

 

I love this thing. It should help me save my strength for fishing rather than dragging a yak over dirt and stuff. One wrong move dragging it and my back could freak out on me and ruin the day. With the cart placed near the center I can lift it with my pinky.