I threw these together in about 2 hours with some scrap wood and about $10.00 in angle iron and nuts/bolts/washers from Home Depot. I use a couple small 2" clamps to secure the pf to the angle iron (49 cents each, Harbor Freight). They weigh about 2 lbs and I can store them anywhere.

Next time I do a swap I'll screw a couple removable cross member pieces from one end to the other for added stability, but this worked just fine for my first time. If I did a lot of these I could see the benefit of one like yours - that's heavy duty - nice work.
20171204_133835 (resized).jpg20171204_134006 (resized).jpg

i leave the wrench hanging from mine since it tightens from the side, not the top. That way I don't lose it, too.....

20171204_133835 (resized).jpg

20171204_134006 (resized).jpg