Hi again !
Many thanks everyone for your replies.
The word-authority on National resonator instruments is called Mark Makin, from England.
He just published a new book on National instruments, about 2yrs ago, and was a major contributor to a previous book on Nationals, by Bob Brozman.
I asked him about steel strings on National ukuleles - as I had previously seen some online discussions about steel strings being mentioned for National ukuleles, in original 1920's & 30's catalogues, from National.
Mark told me that funnily, he had JUST had a conversation about this very subjects a few weeks before, with two other WELL known names in vintage National instruments - mainly a collector with a vast knowledge of these instruments (Colin McCubbin,
www.notecannons.com) and possibly the most experienced luthier in the world at restoring vintage Nationals (Marc Schoenberger,
www.nationalguitarrepair.com).
They concluded that the wording of National's original catalogues, in the section about (instrument cases, spare parts) and strings, that the wording may have led to some misinterpretation about what to use on National ukuleles. It says something like "always use the best steel strings for National instruments".
Some vintage National ukuleles have been found to have steel strings on them AND sound good.
So, with that information floating around on the web, in some quarters, it has become possible common-knowledge that steel strings are OK to use on vintage National ukuleles.
However, the conclusion these knowledgeable guys came to, is that steel strings were NEVER intended for the National ukuleles - which many of you may be quite glad to hear cleared up.
I'm not sure if the subject of steel strings, for Steve Evans, of Beltona guitars (& ukuleles etc) has been an option for his ukuleles, because of the general assumption(s) stated above, or if he always fancied trying that, without ever hearing the common misunderstanding.
In any event, Steve Evans of Beltona DOES offer steel strings on his ukes, as an option - but he told me that standard friction tuners will not hold steel strings - and recommended to me the Gotoh Planetary tuners, if I didn't want guitar-style tuners.
We have already discussed him converting my custom 5-string tenor Beltona reso uke to steel strings - I just haven't sent him my uke yet.
So I have discussed this stuff with Steve - but at the time he couldn't remember what string gauges he recommends (as partly, I'm not sure if he has done that for Tenor ukes before, let alone a 5-stringer). He said the uke will need a new biscuit bridge and possibly a new nut - hence, I will send it to him for all the necessary changes.
The point in this thread was to see IF anyone else had tried steel strings - and see what worked for them - and that way, I would have more than just Steve's recommendations alone.
So, of course I wasn't just gonna throw steel strings on my uke and see if it collapsed or not, without asking around first !!!!
I'll let you know how I get on.