STM32 up date.
At this time we've shipped 100 C kits, a few PCB boards and maybe a couple B kits. For this reason I'm dropping the B kit due to lack of interest. If your uncle owns the plant making the STM32 modules and you just don't want to pay for one, let me know and I'm sure we can work something out=8)
By limiting things to A and C kits I can pre-pack the kits and get them out quicker. I find that when I do several at one time there is less opportunity for forgetting anything.
Pricing (Good News)
I've dropped the price of the Kit C to $30.
Most of the items needed for the kits comes from PRC (a/k/a China). In spite of the "trade war" there has been no impact on prices. Amazon and Walmart have instituted 2 day shipping. Feeling the pressure, Chinese aggregators are compelling vendors to use air freight to make quicker deliveries. Where 6-8 weeks were the norm in the past it seems more like a couple now. Of course this cost is being passed along, but the shorter delivery times mean I can order from the vendor offing the best price. Also, I do not have to go to Amazon, Ebay, etc. to get quick delivery to fill inventory shorts at higher prices.
Additionally, the demand for kits has given me the confidence to order parts in larger lots. This gets us somewhat lower prices, reduces the impact of the newly imposed shipping
costs and encourages me to keep a larger inventory. The only exception to this are the PCBs. JiaLiChuang is a great supplier, but they ship by DHL. DHL's fees go up in lock step with the size of the PCB order and in fact amount to about 50% of the boards cost. So I'm holding the price on the PCBs to $5.
We will be offering a MiniPCB ver. 2.X kit soon. It will be similar to the Kit C, PCB and all components except for drivers, which will be an option. The MiniPCB uses the 4 CORE Teensy 3.2 (96MHz) or 4.0 (600MHz). Thus it's about 1/3rd or 8 and 1/3rd faster than the STM32. The other advantages are that the PCB is about 1/3rd smaller than the STM32, there are fewer components to solder, has a few more options for connecting the steppers to the board and no need for jumpers.
Down side is the Teensys are over $20 or about 10x the price of the STM32 processor module. Pricing will be $55, less shipping, which should be about the same as the STM32.