Materials for Folding Screen

[John P]

Hi,

After some years of putting it off I've finally started getting materials together to build a folding screen for my Ulsteroid.  

The two problems I've come across are the 7/8" brass tube for the bottom tube and 7/8" half round steel bar for the side irons.

I can get 3/4" half round bar although I would have to buy a 3-metre length and I'm not totally sure it would be OK as the bottom tube of the finished frame has reinforcing around the ends which would mean that where it contacts the side irons it will actually be around 1" diameter.   I don't have the facilities to mill it from round bar.

It also seems impossible to source 7/8" brass tube unless it's extremely expensive.   I did think about using 22mm copper pipe as used in plumbing but am slightly concerned that soldering, especially silver soldering, might anneal the copper to the point where it becomes a bit too soft.   It's also a bit thin which may be an issue where the wing bolts pass through it.

I know screens are available but I really can't spend something like £900.

Any suggestions / comments.
John.

[Tony Griffiths]

Does this help? It does not seem to be too expensive https://www.collegeengineering.co.uk/pro...o-d-x-20g/

A 1” OD x 16g tube has a wall thickness of 0.065” and a tube ID of 0.870”

It appears to be available in a maximum length of 24 inches - but sections could easily be spigoted together with a solid piece turned down to suit.

If you have a drill, why not fit a cheap and nasty compound table and used it as a milling machine? Working in steel would be very tricky and require great patience and tiny cuts as the cutter will try to work its way out of the chuck (unless you've a Morse taper drill and can fit a collet chuck). https://www.ebay.co.uk/itm/175219513799?...BMluCAweRj

[Chris KC]

It's sometimes worth checking to see if you can buy inch sized items in America, specially if you (or friends) have plans to visit (postage is rather dear these days).

[Robert Foreman]

Try Macc models for the brass tube.

   https://maccmodels.co.uk/shop/materials/...ss-tube-2/

[Dave Wortley]

I made my side irons from steel tube, cut it down to a D shape and used a piece of 1/8” flat bar to finish off the D shape by welding and found a piece of scrap steel tube as the bit that fits in the brass tube. This bit is the same as the chummy type and has a sawcut down its length and a slot for the wing nuts. It is welded to the DShape. A piece of bar was turned to fit the inside of the tube and tapped 5/16” BSW. Leave a collar on the end of the bar so that it doesn’t disappear inside the steel tube.
Difficult to describe in words but I think a drawing is in Chris Gould’s “Replica Ulster “ booklet.
Not a good description I’m afraid and it’s from making them forty plus years ago.

[Charles P]

For the sides get some thick flat bar and attack it with an angle grinder and powerfile. Unless you’re planning on making  a rivet perfect replica you can get near enough with care, attention and a profile template especially for the shortish lengths that are needed.
Either that or slice some 7/8 round bar from College Engineering. Boring but possible.

Robert has recommended one of my regular sources for the round tube. A good and reliable supplier.

[Tony Griffiths]

"I made my side irons from steel tube, cut it down to a D shape and used a piece of 1/8” flat bar to finish off the D shape by welding and found a piece of scrap steel tube as the bit that fits in the brass tube...." You'd never guess that it wasn't an original solid piece (lighter, too...). Typical zero-cost but high quality Wortley workmanship.