Does anyone know where I can buy an empty 600ft box

There is a seller on ebay who sells them Dave. Typically, in packs of five.

Cardboard?

Classic sells them david.

The ebay one's are not bad quality, a bit pricey though. Not tried the CHC one's. if your after boxing up a feature and just the reels, cake box's are worth a look, good quality
and better value.

CHC has very thin boxes, at least the 200' ones. I ordered more, but would have liked that guy selling on eBay before to get back in business. They were very good

CHC boxes, on any size are not fit for purpose imho.

They are made from the complete incorrect grade of card. They are a similar thickness to what you'd expect your local bakery to package 4 cream cakes into.

A complete waste of time and effort.

The ones off ebay are not the cheapest, but they are the correct grade of card to house films into. That even includes the 1200 ft ones.

Very similar to the ones that used to be offered by John Vidler a while back.

Yes, Mr. Vidler, that was the guy. Wish he returned :-)

There's no money in it Vidar. Not a chance of him returning.

I got all of his remaining 1200ft stock, just wished I'd done the same now for his 600ft stock.
At the time I was taking stock off 600ft reels to place on much larger reels but 600ft ones are definitely the most popular and most wanted by collectors overall.

Can still wish ;-)

The only guys left still selling film boxes, sell for huge profit but accept unbelievably slow turnover. Not many now are prepared to lay out a few hundred quid and wait a couple of years to see the return.

Regarding CHC boxes I have to say I like them. Yes they are thinner cardboard but they are 'whiter' and the finish is good and smoother, better than the finish from the vidler boxes. I used a 400ft from him and the box fell apart as the glue seal broke. The CHC boxes have a design on one side but if you are reboxing a derann film you simply cover the design with the Derann artwork. Granted they maybe wont last as long but they look nice when new and if handled correctly.

Graham S

Well it's each to their own of course Graham, but if it's durability you're after, even if you cover the boxes entirely with artwork like I tend to do, then for me, the only ones up to the job are the grade now only currently offered on ebay from time to time.

So far I've had no issues with the seams coming apart either.
That includes all of the 1200ft ones I purchased from John.