Pre-Order Discussions

Do you have any suggestions? 

I'd like to get away from Chinese sourcing if possible--just I'm not aware of any platforms like Alibaba for any other countries.  (Yes, Alibaba does support other countries, but there's basically no suppliers on any of them.)

All you need to drill and tap heat sinks. Just add variable speed and reverse.

https://www.harborfreight.com/power-tools/drills-drivers/drill-presses/8-in-5-speed-bench-drill-press-60238.html

All you need to cut heatsink extrusions.

https://www.harborfreight.com/power-tools/power-saws/miter/7-14-in-single-bevel-compound-miter-saw-57174.html

46 minutes ago, Sid Genetry Solar said:

Because we weren't dealing with 0.5mm precision most of the time

.5mm is .019". That's huge. I know they were building machines to .003" or better back then. When I first started machining I was amazed that parts were made to .001" accuracy. Now it's no big deal. Look at the edge of a piece of printer paper. That's usually around .004"

46 minutes ago, Sid Genetry Solar said:

All we need to make the cases ourselves is a CNC table (2 axis)

You can't buy the steel for what you can buy those cases for much less cut and bend them.

Stainless has some drawbacks. If it gets scratched then you have to repair the scratch which means reapplying the brushed finish to match. If your hell bent on using stainless then plan on brush finishing the hole case after fabrication or plan on shipping them with scratches and pressure marks.

46 minutes ago, Sid Genetry Solar said:

Try over a hundred THREADED holes per inverter (SS case + aluminum heatsinks included) in 4 different sizes.  Bit harder to do that in 30 minutes.

I was talking about the case in 30 minutes. Heatsinks might add another 10-15 minutes

46 minutes ago, Sid Genetry Solar said:

It has to be able to sling around a 100lb core without buckling

It would be impractical to try and run 100 lbs cores at the speed in that video but if you ran it slow then the mass wouldn't be so bad. So what if you can only wind 2 a day. That's 2 more than you have right now. I'm thinking a machine of about 400lbs running so slow you could visually count the revolutions. Like a 3d printer. Slow but it eventually gets done.

46 minutes ago, Sid Genetry Solar said:

It'll probably need a 2' diameter winding ring. 

No big deal. Wood, Aluminum, Fiberglass, Steel.

46 minutes ago, Sid Genetry Solar said:

spool handling ability of several hundred pounds

The spool doesn't need to sit on the machine. Use a commercial wire spool holder or build one.

46 minutes ago, Sid Genetry Solar said:

If the machine doesn't outweigh the materials by several times, it's going to be very unstable/unsafe.

Not true. Run it slow and brace it properly. You can also add materials like concrete as a ballast.

I know you don't want to quote prices so percentage how much and how easily can you get the cores verses the finished toroids? What percentage of cost is the core? If you could save enough then maybe you could go to copper windings instead of aluminum.

14 minutes ago, OpenNRG said:

If you could save enough then maybe you could go to copper windings instead of aluminum.

Someone doesn't know what they're talking about.

36 minutes ago, Sid Genetry Solar said:

Someone doesn't know what they're talking about

I read somewhere you were using aluminum windings. I believe it was on diysolorforum, maybe here. Didn't mean any dis-respect.

Here's where I read it. Few posts down on 1st page.

https://diysolarforum.com/threads/genetry-solar-6kw-inverter-review.25057/

We are.

We are also the ONLY inverter company (to my knowledge) that has a 12kw inverter that can ship regular parcel mail: shipping weight of less than 150lbs.

EVERY other 12kw inverter on the market (that I have found) weighs 180-250lbs, and must ship LTL freight.

Not to mention that going from aluminum to copper literally TRIPLES the cost of the transformer (quote difference from the same manufacturer).  And significantly increases the weight.

Zero benefits for us.

1 hour ago, Sid Genetry Solar said:

Someone doesn't know what they're talking about.

Then why did you make this comment? Was only trying to help. I'm done. Good luck.

Then why did you make this comment? Was only trying to help. I'm done. Good luck.

I hope you are not done .      People  say I do not know what  I am talking about  here  all the time .      I  believe you  as I also  do machine work  a long time ago .      

1 hour ago, OpenNRG said:

Then why did you make this comment?

It's the old adage, "everyone knows what to do with a kicking bronco until they have one."

I could go into exhaustive detail on why I made that comment, but that's besides the point and not beneficial.

When I make a statement about something, I generally have done my research on it, know what options are available--and have a reason for picking a particular direction.

In brief...

• Maybe you can get 0.005" precision out of a $80 Harbor Freight drill press.  I know I definitely can't--nor do I know anyone who can.  Ditto for a metal cutter--sure, it can cut aluminum stock for a little while.  But it DEFINITELY is not a production-level precision tool.
• Most of your suggestions are from a DIYer "hobbyist" one-off design perspective.  Yes, your suggestions could be utilized to give us "just 2 more than the 0 you have right now".  But in the big picture, they're completely inadequate or simply unfeasible. 
  • How many months would I have to spend exclusively on making a transformer winding machine before we could make our first transformer?  For just this ONE small aspect of the inverters?
  • How many tens of thousands of dollars of supplies and test materials would be consumed/wasted in the process? 
  • And in the end, only be able to make 2 transformers per day?
    • I'm looking at everything from a "future-proofing scalability" perspective, a sustainable business model.  Because the "slap and done" solution is going to be uselessly outdated before it's even wet behind the ears--and then we're right back where started, only thousands of dollars lighter and many months lost.
• We use stainless steel because it is very strong, and much "springier" than most other metals I know of.  Almost any other metal will deform WHEN (not if) the package is dropped in transit, due to the very heavy transformer.
  • Can't buy the stainless steel alone for the cost of that Chinese case on Amazon?  Seriously?  (It's straight-up nonsense like this that makes me comment things like the above.)
• As always, I continue to stress...it's NOT that things can't be done in the States.  It's just that it's usually impossible to justify the COST (or timeframe required) to produce things here.

Didn't realize you had your transformers in hand already. Just watched the video. Nice.

12 minutes ago, Sid Genetry Solar said:

(It's straight-up nonsense like this that makes me comment things like the above.)

Haven't used Stainless Sheet in several years but the price for 16ga 48" x 120" 304 about 6 years ago was $273.00. It might be twice that now.

I'm done. No need to reply.

Good Luck

You need new suppliers 😉.

We were just looking at suppliers 2 weeks ago, and a 4x8 sheet of 16 gauge 304 was ~$90 from one supplier...and $950 from another.  For the exact same thing.

Just a sample test one.  We have the (Chinese) supplier nailed down, and will be ordering the bulk batch after the factories reopen after CNY.

A toroidal winding machine of the size necessary for winding GS inverter transformers--will weigh several TONS!

I  watch the DYI  toriod winding machine  youtube  and it is not useful to wind a  12kw transformer .     

I would estimate that the SendCutSend quote for the complete GS6 case @ 10pcs qty (as their single piece pricing is horrid!) would exceed $500 per unit.

I can  buy  10  Powerjack 26 kw NOT  working inverters from Walnut  for less than 500 dollars each  .      I will sell  the  mainboard  and the transformer  for more then 600 dollars on ebay  and have a free shell for the  GS 12kw  or the GS 6kw . What do you think of that ?     

Loss-leader / scratch-and-dent / discounted "clearance" / or one-off deals, etc. are completely useless for production-level sourcing requirements.

Besides, I already wrote that the SendCutSend price was way too high...so it doesn't even figure as a baseline.

February 2, 2023:

• I am actively digging through sourcing parts for the inverters.  Found an OEM capacitor company that looks like they can produce the main filter caps for our inverters.  Sure beats a "trading company" that might sell capacitor-shaped items that are full of wax or something like that!
• Spent a good bit of time on the phone with the guy at Sean's local machine shop.  And...Sean likes to tease me, "I know engineers, they like to change things."  Well, some of you may have noticed that the "foot" on the new design GS inverters, does not go all the way to the front and back of the inverter.  This was a requirement due to PJ's production limitations--but this absolutely does not apply to the local machine shop.  In other words, I can adjust the design to bring the mounting feet all the way to the front and back of the case.  Might as well, as it'll increase the strength of the case anyhow.
  • this will not delay the order production--the items with the longest production time likely will be the transformers, from our new transformer supplier.  They'll have to ship by ocean, simply because their weight!
  • The change would extend the mounting feet flanges all the way to the edges of the case, through the highlighted spaces here:
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