G' Day Folks
Recently during the SPIRO 111 building thread, Rich was saying that his idea was to try to cut cost's on the project and that a Uni joint in the UK cost around 10 pound.As it so happened at the same time I picked up one on Ebay for $ 6.00 AUD {that's cheap}.
When it arrived I thought that it was not out of my reach to make something similar. So I used what I had on hand at the moment which was some 10.mm OD Ali tube /2-56 bolt and some brass tube that is a good fit to the bolts.
I am sure that carbon or plastic tube or Square section would work just as well.The first one I made took about an Hour & the second took half that time.
I simply filed grooves in the end of the tubes,and drilled holes for the bolts.
The swivel was made from 2 pieces of Brass tube lashed together with Carbon Rovings ,then hit with thin CA.[ I am sure that strong thread or Glass rovings would work just as good ],when dry the X was cut off the end of the tubes.and sanded to fit.
A little grease in the tubes and pop in the bolts.and Bob's your Aunty
I am pretty sure this method could be used on larger models .just a matter of adjusting the size of the components to suit the job.
Some of you may think it is a wast of time when UNI joints are available in stores ,It's just that I am old school,and always enjoy being able to make as many parts of my models myself.
Happy Landings
Chris.........
I hope these Pics tell the story

Chris,

that's a nice solution. Have you tried soldering the brass tube joint? Tht may even be more simple.

Jochen

G'Day Jochen
Yes I am sure that soldering would be easy,but to tell you the truth,I never solder.
I use this method of carbon rovings with thin CA on all my U/C jobs,and it has never failed.even on my larger fixed wing models.
I also used this method when I built my two Minimum's The Carbon frame was assembled dry in stages. I know that using wet rovings can be a pain. [The last 24 years of my working life has been hand making carbon model and full size props ,so I am
very comfortable with this material]
Happy Landings
Chris...........

Thanks for sharing Chris! That's my type of stuff....homemade!

Chris, that was a really cool idea.