[PSUBS-MAILIST] Acrylic Dome

[Alan via Personal_Submersibles]

Tim,
I had been interested in making my own brushless underwater thruster as there
wasn't anything cheap on the market around the 2hp size I wanted.
Brushless have more torque are more economical & better suited to oil
compensating than brushed, & I am wanting them for a 500ft depth.
I have used 6374 (dimensions in mm) brushless hobby motors wound to 60kv 
( rpm per volt ) for higher torque. I wanted to avoid gearing. 
There is a major manufacturer ( Sunny Sky ) that I approached.
I started with a product they made that was a bit more substantial, having a 
can bearing on it. I had previously trialed another 6374 motor without can 
bearing & decided it needed one.
They put a 316 stainless shaft in it to my specs with Circlip groves cut in it.
They machined the back of the motor to let the wires comes straight out the
back rather than top. They also put a hall sensor board in so I could run it
sensored. And as mentioned wound it with thinner wire. Cost less than $100 each.
I have bearings in my housing that take the axial load. Am compensating with
5cst silicone oil so should be good for the motor bearings.
In tests it was above average with regards to commercial motors as far as thrust 
per Watt was concerned.
Have more tests to do, but I have a video of it powering my inflatable on my
Facebook page somewhere.
Cheers

> On 18/01/2020, at 2:06 PM, T Novak via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
> 
> Thanks, Alan.
> It would be interesting to hear the specifications under which your new motors were manufactured.  Could they be something we could all use as a source?
> Tim
>  
> From: Personal_Submersibles [mailto:personal_submersibles-bounces at psubs.org] On Behalf Of Alan via Personal_Submersibles
> Sent: Friday, January 17, 2020 3:44 PM
> To: Personal Submersibles General Discussion <personal_submersibles at psubs.org>
> Subject: Re: [PSUBS-MAILIST] Acrylic Dome
>  
> Tim,
> some of those young girls know their stuff but communication looks like
> It may be difficult in this case.
> With regard to an acrylic dome, you would have to be pretty specific &
> see material certification & question them about the process first. Then
> check the dome with a spectrometer for any stress after forming & then
> pressure test it.
> It would almost pay to visit first.
> I had 11 motors built in to my specs, with a 316 shaft etc  & the manufacturer did
> a really good job.
> Alan
>  
>  
>  
> 
> On 18/01/2020, at 10:38 AM, T Novak via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
> 
>  
> Whoever made her t-shirt  can't spell.  But she is just the "teenaged girl across the counter", not the seasoned technician. You don't know the quality until it's on your bench.
> Tim
>  
> From: Personal_Submersibles [mailto:personal_submersibles-bounces at psubs.org] On Behalf Of Alan James via Personal_Submersibles
> Sent: Friday, January 17, 2020 12:40 PM
> To: psubs.org <personal_submersibles at psubs.org>
> Subject: [PSUBS-MAILIST] Acrylic Dome
>  
> Looked on Alibaba to see what China offered in the way of cast acrylic domes. 
> Was contacted as they track your search history. 
> Have doubts about the firm already as below is a picture of my contact! 
> Alan
>  
> 
> <image001.jpg>
> 
> Sent from Yahoo Mail on Android
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.whoweb.com/pipermail/personal_submersibles/attachments/20200118/d8f74667/attachment-0001.html>