Primary tap connector.

[thedoc298]

Looking for ideas for to buy or build a good heavy duty clamp for the primary tap. Been using like battery charger clamps but not liken them. Would like something from copper, any ideas...? Been googling and not found anything that will work. Thanks all 

[davekni]

How about a split-bolt connector such as:
https://www.homedepot.com/p/Commercial-Electric-4-1-0-AWG-Copper-Split-Bolt-GOEC-25/310741810

[TMaxElectronics]

I make mine from spare copper busbar. Just cut off two pieces (around 25mm / 1 inch, could be shorter) and drill a hole through both at one end. Then put a thread into one of the holes with a tap, and drill out the hole on the other piece to allow the scre to slide through. Finally you screw the two pieces together with that screw and drill a hole sideways inbeteeen them that is the diameter of your pipe.

That makes a clamp that you can attach a wire lug onto and clamp down to the primary pretty nicely. Lasts forever too. Just be careful with the spacing to the next turn and your secondary, mine is certainly pushing it in terms of clearance and a sharp edge.



If you find that the clamp doesn't clamp too well then you could either try using a slightly smaller drill (although even 0.5mm less than the pipe diameter will look bad), or put a few sheets of paper inbetween those pieces before you screw them together for drilling the sideways hole.

[MRMILSTAR]

I make similar clamps from aluminum. I also place a short section of vinyl tubing on the adjacent turn to prevent any accidental arcing between the clamp and the adjacent turn.

[thedoc298]

How about a split-bolt connector such as:
https://www.homedepot.com/p/Commercial-Electric-4-1-0-AWG-Copper-Split-Bolt-GOEC-25/310741810

Last night as I was returning to the basement I got your idea and I have many sizes. Working on one now trying to grind it to fit, not much room to work with, also going to try what tjmax showed, same thing though with the spacing.   Thank you guys for the help, if not for the top ideas and help I would never have learned all this stuff about coils. I get something made I will post. Thanks again.

[Mads Barnkob]

For my large DRSSTC I used a modified overhead mains wire clamp, but it could also just be homemade from copper bar as Tmax says. Same principle. Pictures somewhere at: https://kaizerpowerelectronics.dk/tesla-coils/kaizer-drsstc-iii/

For my weird test DRSSTC I used large bussman fuse holders, fits perfectly on 10mm copper tube. The other end connector is also a worthy and cheap solution. A U-bend piece of copper sheet with braided copper going underneath, makes for a snug fit with very good contact. Pictures somewhere at : https://kaizerpowerelectronics.dk/tesla-coils/kaizer-drsstc-iv/

[Hydron]

Use a fixed primary and tap the MMC

Only joking a little bit - if you have a MMC arrangement that has enough series and/or parallel caps and voltage/current headroom it can be adjusted, with fine tuning done if needed with the length/orientation of the lead wire to the primary (haven't tried this second bit myself).
To get it close initially either simulate the coil well or use an temporary adjustable primary tap and then fix it in the correct spot once found.