because the magnetic switch is normally open (didn’t exist in normally closed or I didnt find yet )
so the small relay is an inverter
Oh ok. Thanks. About the pump… you have it connected to the relay on the maytech reciever. Is that relay operated from a switch on the remote? If so, does that mean you have to remember to turn on and off the pump? Do you recommend using a pump over no pump?
My first melted prop in PLA lost , failed 
not too bad, need improvement.
There was still PLA in the blades
I have to leave the mold in the oven longer to remove all the PLA
I use ski poles, ski boot hooks, cans of coke 
some pictures
5 Likes
Cool experiment to get an aluminium prop at the end. Keep on pouring 
Eventually I would cast a more thin bladed prop, the PM prop isn’t that efficient due to the blade thickness and shape.
1 Like
@Beninspain I know you had a go at aluminium casting, how would you improve this result ?
Jeff, Ben is the guy I mentioned earlier who removed his 12V pump (with the 12V UBEC as well) and installed a forced flow cooling outlet on his board deck to sense the water temperature using his toes.
1 Like
I found the solution to remove the pompe
Same solution like my V1 but with the VESC flipsky ( VESC just behind the mast )
In 1st I wanted to use the smart solution box at @ELEVATE.rocks
But for the V4 I want to reduce all the box
For sure I will use it for the V5 to test it
For the prop melt, i think I need to improve the process to remove the PLA, and the vent hole was not at the good place, not at the top of the prop
My second prop melded => success
after 1 hour of balancing
the original vs melded prop, I think it’s not possible to melt exactly the trailing edge, it’s too small
but we can have a thin trailing edge in post processing
10 Likes
Interesting, I would like to have an aluminium case as well but I don’t have (cost effective) options to CNC a VESC case for a gong mast adapter.
How do you plan on cooling the vesc with a plastic housing? I see you removed the watercooled casing, pcb only now?
who did you make the duct??
it will be in aluminum
the plastic box is the model to melt it into aluminum
Looks good, however, the filament you are using is not appropriate for this kind of work I think.
There are specially made resins and filaments called “castable” which allows uniform melting of the part when Boiling alu of whatever is poured on top of it. Have you considered castable filament ?
Here is an exemple :
https://www.cubictech.com.au/products/esun-esmooth-polishable-3d-filament-1-75mm-0-5kg
2 Likes
thanks for the advice, I didn’t know this kind of filament
I found an other link
I will test it
Oh, oh, oh ! No such result has been reached on this forum. Congratulations !
Looking forward to seeing the performance differences between the printed and the cast versions !
As per the ESC box above the mast, it looks promising. Maybe no machine time or at worst a fast surface finish between lid and box on each face will be needed ?
2 Likes
Looks good too. Make sure to post process your print before casting. You need to smooth the layer height either with Acetone or by sand paper.
As for the sand you are using. Here too, there are specific silica based or synthetics sands made for castings like this :
https://www.amazon.com/Petrobond-Casting-Silver-Jewelry-Alternative/dp/B00XRRKCRO
Here is a comparison of casted parts in different sands :
https://www.globalcastingmagazine.com/wp-content/uploads/2013/10/Figure-4.jpg
Picture from here :
https://www.globalcastingmagazine.com/index.php/2013/10/30/characteristics-of-synthetic-sand-and-application-of-refractory-coatings/?lang=en
1 Like
yes Souleiman you are 100% right, sand is very important.
I tested 3 different sand
The red sand is very nice if you use it directly to shape inside
and for the other I sifted with a small sieve and I mix it (50/50) with a very fine plaster
And I will test next week a plaster for the foundry
I start in foundry so I have everything to learn
it’s really interesting and exciting to learn new techniques.
I need to improve the layout of vent and pipe for cast
Do you know if a “free” software can modelised this ?
thank you for your sharing
5 Likes
New schemactic for my V4, more simple and compact design :
- New dead man switch home made, normaly close
- New fuse 200A home made
- New kilovac 48V
Removal :
- Pump
- Inverter relay
- Magnetic switch NO
- Circuit breaker 150A waterproof
- Sbec 12V 5V
3 Likes
you can actived the kilovac trough a 50v supply directly?
