Paul & Sabrina's cheap DIY 144v motor controller

[lumberjack_jeff]

One project at a time, but you might want to consider a CNC router. They work great for pcb routing.

approximate cost - CNCzone.com-The Ultimate Machinist Community

It can be done for about $1000.

DIY-CNC Router Table Machines - CNCzone.com-The Ultimate Machinist Community

[bennelson]

Originally Posted by lumberjack_jeff

It can be done for about $1000.

Time for a bake sale.

I suppose an internet bake sale would sell cookies?

Maybe you could get a cup of Java with it?

[NiHaoMike]

Originally Posted by GrahamMc

Isn't most of the cost associated with a high end electric motor in the actual hand winding of it? Next project, open source 100 HP open source ev motor.

Aren't mass produced electric motors made by machine?

A switched reluctance motor could get interesting. No magnets - just a rotor shaped to produce torque as the stator coils switch on and off. Just need access to a powerful CNC laser cutter to make all the stator and rotor pieces...

Maybe even use thin copper tubing painted with a special insulation paint as the windings. Then just pump oil through them to keep it cool.

[Wherewolf]

You know....it's kinda funny. In my area, there aren't a lot of guy doing DC motors anymore. I salvaged a DC forklift, and pulled the main traction motor out - found that the armature had grounded out. Burnt the leads off the field windings – oooops! Need to clean the carbon out once in a while…..maybe that’s why I got it CHEEEEP! And 10,000 lbs of scrap metal to boot…..anyway…I took the armature to the local electric shop…they said “Whoa! We can’t turn anything that big… (2 inch shaft - 8 inch diam core, about 18 inches long. Motor weight is 276 lbs) Had to haul it in to 4 different electric motor shops (about 150 miles of driving total) before I found one that could turn and undercut this unit.

Everyone is doing AC only, so there is very little in the way of resources for DC motors here. And they all seem very non-chalant about people doing EV conversions – even though I think it will eventually be a big source of business for them. DC motors need to be pressure washed and baked ; pretty much yearly to keep the carbon dust out, or they load up and ground out. Oh and by the way – the insulated bushings the go though the motor case from the brushes and fields inside to the outside? GE wants $42 A PIECE! Judas jumpin’ up and down, it's BRASS and poly for pity sake! Not Gold! The poor sap working on my armature GAVE me some spares he kept from old motors, because he felt bad about price gouging! I am definitely going back to this guy.! He growled the armature before agreeing to work on it, so he wouldn’t have to charge me if it needed additional repair or was toasted.
If any of you are in southern WA, I would recommend this guy….he’s a straight shooter.


Wherewolf

[jimini]

Originally Posted by MPaulHolmes

I just messed up a 3 ounce board, but I have 23 more, so it's all good. I bought them in bulk from Ebay awhile back. If you want to know the truth, I was trying to keep my

Right 4.5 cranks
Up 5 cranks
Right 2.5 cranks.

etc...

and my mother in law came in and started talking to me. I lost track, and got confused, and messed up the whole thing! I'm OK now! dang it!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Is it difficult to get a couple little motors that get attached to the x and y axis turn things, and then program the motors to do the counting? This is far too annoying for words.

This could help.
Entry Level CNC Carving Machine Kits - eBay (item 180348660780 end time Apr-27-09 09:42:43 PDT)

[nubie]

Don't forget that you can add CNC to your current mill if you want.

@ WWolf

Did you try taking it to a real machine shop? I am pretty sure anybody with a lathe could get that done.

[MPaulHolmes]

Nubie, I want!

I signed up at the CNC place. I need to ask them how to CNCize the dang thing.

I modified the old control board some. I replaced all the ICs, just in case they were "walking wounded" from the earlier mishap. hehe. I also improved the throttle, and changed a resistor to use the LEM 300 instead of 500.

The cheap ATMega8 from china is causing me problems. It isn't allowing me to do optimizations, and it isn't recognizing the new crystal oscillator. Maybe I got ghetto ATMega8L's that china changed to ATMega8-16PU's? Oh well. I'm just wanting it to work for the Alternative energy fair on Saturday.

[Roger Heuckeroth]

It just so happens that I just adapted a router to my CNC table. I will be milling teflon sheets for some electrochemical cells I'm working on. I'm using a high speed Dewalt router, so I'm not sure how well it will work for cutting copper off of PCB boards. Generally for metals you want a lower PRM, but it would be probably a lot cheaper to adapt the right cutting head onto my CNC than it would be for you to adapt CNC controls to your mill.

As I mentioned earlier in this thread, this machine is originally a CNC plasma cutter. Now its also a CNC router table. The CNC program doesn't care what tool is on the fixture. All it cares about is X,Y,Z.

Anybody have any ideas on what type of tool / RPMs would be best milling copper?

[dcb]

Originally Posted by MPaulHolmes

It isn't allowing me to do optimizations, and it isn't recognizing the new crystal oscillator.

Maybe it is a fuse thing? Also, can you read the device signature off the chip to confirm?

[MPaulHolmes]

Originally Posted by Roger Heuckeroth

As I mentioned earlier in this thread, this machine is originally a CNC plasma cutter. Now its also a CNC router table. The CNC program doesn't care what tool is on the fixture. All it cares about is X,Y,Z.

Anybody have any ideas on what type of tool / RPMs would be best milling copper?

I've been using that PCB milling bit. It says to run it at high RPM, so I've been running it at 1500 rpm. It has a 1/8" non-cutting end (to be held by the machine), and a 7/32" cutting end. It cuts very clean if you don't go too deep into the PCB. If your machine can accept 1/8" diameter objects, and can run at around 1500 rpm, I'm sure it would work.

Probably the easiest way is to get a pcb that is maybe an inch bigger in the x and y-axis direction, "lock it down" flush to the table somehow or other, and etch the designs and drill the holes, but not going all the way to the edges (since there's an extra inch in x and y direction), flip it over "precisely", and etch the other side, and then do a final rectangular cutout to the correct size. Otherwise it causes problems, and is SUPER annoying to cut all the way to the edge. Maybe if there existed a table that has a suction on it, you wouldn't need the extra length and width.

DCB: I don't think it's the fuse settings, because I've followed the documentation, but it could be that. I'll try the other possibilities too.
I've read the device signature, and it confirms that it's an ATMega8, but that doesn't confirm that it's an ATMega8-16PU. I suppose it could also be a ghetto ATMega8L, which can't be run at 16 MHz.