Wanting to twin a DF 28 Pathfinder

[srislash]

Looks good Ray. Haha can I join the slow man group? It would be all Canadian content

[Alfa Spirit]

I remember a fast Genesis with 8S batteries and 1300kV motors, good autonomy too, 8S for both motors. He used HobbyWing 80A HV escs.

[ray schrauwen]

I remember a fast Genesis with 8S batteries and 1300kV motors, good autonomy too, 8S for both motors. He used HobbyWing 80A HV escs.

I remember that too.

[ray schrauwen]

O.k. I have the struts mounted and rudder mounted too. The struts are adjustable in height and angle.

My question to twin builders is how low do you mount the strut? I mean I could build flooded stuffing tubes but prefer it more simple and clean. Props will need to be angled down some since they are ABC 17 series props and the Stainless steel Proboat props first.

Where to drill these holes???

4mm of height adjust-ability.

[TRUCKPULL]

Ray
I would say that your struts should come down a little.

The first picture is of my 6S twin, struts are down 2 Degrees (I may lower this one some more)
Second picture is of my 8S twin, struts are down 2 3/4 degrees.
The ruler is 24" long and sitting on all three ride pads.

If for example that your strut measures 1/8" from the bottom rear to the bottom of the 3/16" drive shaft.
On a flat surface set the boat on four pads of 1/8" thick.
Now with the struts set at 2 degrees, lower them untill the bottom edge touches the flat surface.
At this point check to make sure that the tube will clear the inside bottom of the hull.
If not you will have to rise them a little, if it is a lot you may want to consider longer struts.

Larry

[ray schrauwen]

Thanks Larry, I'm reading it over. Sorry I missed your call last night.

So you measure the strut angle with your digital gauge like I have and you do it from the bottom?

[ray schrauwen]

Well... looking at pics of Larry's old MM twin, he had to put the batts on top of the tunnel and I don't want to.

While test placing everything in the hull to see where the CG is it becomes evident why Larry had to put them there on a 29" cat. I remember in the past Ken Joye built a Drifter M or L and he put the pair of motors on top of the tunnel instead and I think I'm going to fill in the 4 holes I already drilled and put the struts right about here instead.

The motors will be easier to install, maintain or change, the batteries then have ample room to move around in the sponsons for proper CG while keeping weigh low. I will be using a pair of brass Metric stuffing tubes because the TFL struts are bored out to 7mm Metric and from a 7mm tube to 6mm tube the Teflon tubing still fits properly inside for 0.150 cables. Using long stuffing tubes allows all the strut adjustments I could ever need.

[ray schrauwen]

1950KV twin? I bet you could run them on 6S.

I'm thinking about this now too. We will see after it's done.

[ray schrauwen]

Well, it's finally time to mount the servo and finish this thing.

I was thinking of using a pair of Sullivan golden rod cables going through brake cable sheathing.

Would that then be push pull or pull pull? Is there a draw back if it is pull pull? I want to use 2 cables but not if it's inferior to a thick single solid rod.

Help??

[ray schrauwen]

Slowest build in the world??? Perhaps...

I'm just figuring out cooling lines and some wiring ideas but it's pretty much done.

I want to try PB 1716's I have first but besides those I have no idea what to choose for 4S power through a 2200kv.

If I stay with 1.7inch props or smaller I can use my Hughey flex cables. If I go to a 1814 or so then I need drive cables with longer stubbs.

Any help with props is appreciated.

[properchopper]

Any help with props is appreciated.

https://www.youtube.com/watch?v=JgRzweFct0M

[ray schrauwen]

Your humor is always welcomed here Tony.