I have been commissioned to make a pig roasting spit for a friend. We have settled on a height but I am unsure about the length for the spit and size of materiel. He said that he only wants to roast a pig about 50 lb, though I suspect that this may change in the future.

My questions to anyone who has experience making or using a spit like this are, would 3 ft between uprights be sufficient, and would 1/2 in. stock be strong enough.

 Thanks in advance.

The one I had had a 1" Stainless steel solid bar for holding pigs.

I would go five foot 3/4in stock. he would be limited with three 1/2in and even a 50lb pig would be crowded.

Tubular sections are stronger than solid bar pound for pound. You want the central holding bar/pipe strong enough to not fail, and I would not consider 1/2" even remotely close enough for starters.

22 hours ago, BIGGUNDOCTOR said:

Tubular sections are stronger than solid bar

So 1" black iron pipe?

 

If you use tubing use square. That way the prongs won’t rotate and a simple wingnut will act as a set screw. 

My friends and I routinely roast Vietnamese pigs and a 50# live weight pig will take every bit of 3” and a 50# dressed one 4’ plus, 5-6’ between uprights minimum

I searched "Pig roasting spit" and received a lot of answers

Reading this reminded me that I've seen spits intended to hold a flattened carcass between what is basically metal fencing.  The hog isn't so much rotated as flipped.  

A lot of commercial barbecue places do the same when grilling large quantities of chicken. I remember seeing one outfit that had a long series of firepits made from 55 gal. drums split lengthwise, and they'd just keep flipping the grates down the length. By the time a grate reached the end, its meat was done.