Cheap spot welder or DIY CD welder?

[jmamcarson]

I'm looking at getting a spot welder and need it to work fairly consistently (nothing insane) for building e-bike battery pack. Should I get a cheap Chinese spot welder like the Sunkko 709AD or just build a CD spot welder. I can afford the $300ish for the chinese one but the cheaper the better (which is why I'm looking at DIY) and if I can get similar results with $50 of capacitors and electronics that'd be great. What are people experiences with CD spot welding, how many joules do you need, and is it worth it compared to cheap prebuilt units?
P.S I cant get one of the cheapest chinese ones as it'd fry my house's wiring after a couple of welds

 

[amberwolf]

What are people experiences with CD spot welding, how many joules do you need, and is it worth it compared to cheap prebuilt units?

Does this thread help?
https://endless-sphere.com/forums/viewtopic.php?f=2&t=2633

 

[flippy]

just get this one if you are on a budget.

https://malectrics.eu/

 

[Headrc]

So far I am very happy with my Kweld ...although it might be more than your budget.

 

[spinningmagnets]

The Malectrics and kWeld seem to be the most popular.

 

[fechter]

I have a JP spot welder:
https://endless-sphere.com/forums/viewtopic.php?f=31&t=68865
This is like the Kweld but simpler. I've had very good results using a small 3s Lipo battery as the source.

There are several other similar units out there.
https://endless-sphere.com/forums/viewtopic.php?f=31&t=81274
https://endless-sphere.com/forums/viewtopic.php?f=14&t=89076

Any of these work better than a Sunkko.