M42 lenses with metabones Nikon mount

I want to use my m42 lenses on BMPCC4K but connected to metabones with Nikon mount, there's is any problem using the cheapest rings for m42 to Nikon and connect directly to metabones? Since metabones with Nikon mount don't have any electronic connection I thinks there's is no problem. Right? What's your opinion? Thanks

If you get a good quality M42 to NikF adapter, should be fine as far as mechanical connection, other than you are stacking lens adapters (which can be troublesome sometimes). Optically, it will depend on the M42 lens being used.
Cheers

M42 has a flange distance of 45.46, Nikon F 46.50 so you will only be able to use it for macro shots.
Get yourself an eos speedbooster for your m42 lenses.

Yes, the M42 to Nikon F adapter is only about 1mm thick, very thin, and since is uses is entire thickness to screw on the M42 lens, it is just making up the FFD difference and adding the NikF bayonet lugs to the M42 lens. That is why you want a good one, that is built accurately to these close tolerances.

The down side is being very thin, it will flex or may strip the threads. So you want something that will not strip out and hold the lens adequately in the adapter.
Cheers

Great tolerant advice ...if you don't mind loosing focusing to infinity.

Yes, that would depend on the lens and the adapter, and as with any adapter/lens combo, this can be an issue, especially when you start stacking adapters, which is why I normally recommend not doing this.
That said, some users have had good luck with this combo.
Cheers

If that acrobatics does not work, try PixCo m42 > m42 focal reducer and adapter (63$ https://www.aliexpress.com/item/Focal-Reducer-Speed-Booster-Turbo-Adapter-for-M42-Mount-Lens-to-Camera-M4-3-mft-GH4/32706068610.html?spm=2114.search0604.3.2.1c57c76c5S1yTn&ws_ab_test=searchweb0_0,searchweb201602_6_10065_10068_319_10059_10884_317_10887_10696_321_322_10084_453_10083_454_10103_10618_10307_537_536,searchweb201603_16,ppcSwitch_0&algo_expid=4d984cca-6ca6-46f3-a54b-634ed55aa990-0&algo_pvid=4d984cca-6ca6-46f3-a54b-634ed55aa990&transAbTest=ae803_3 or 91$https://www.amazon.com/Pixco-Focusing-Infinity-Booster-Reducer/dp/B00HPPHRQ8), work nice to me.