A good source of 3/16 inside diameter plastic tube
Prepared by: Tommy Day
Originator: Michael Druiett
Evening all,
Can anyone point me in the right direction please.
I'm looking for a small amount of some 3/16 diameter inside diameter tube to be used as an insulated axle sleeve for making split loco axles.
Does anyone know any stockists, cant seem to find any…
thanks in advance
Michael
Buckley10339 - Jul 15, 2018 at 9:26 PM
Eileens emporium in the traders website should do it or Hobby hoildays definitly do as i have got imperial tube from them in the past.Or just Google brass tube.
Pat.
edited ,Sorry dislexia kicking in didnt notice the plastic part of the request.However a google search of plastic tubing should work as all the aeromodeling shops will stock it.
Buckley10339 - Jul 15, 2018 at 9:42 PM
Micheal put small plastic piping into google i just found 5mm piping on there from Amazon. 5mm is just a bit smaller than 3/16 but it should fit quite well and will be quite tight.If you need rigid plastic tubing just google Plastruct.
Pat.
Jim Snowdon - Jul 15, 2018 at 10:10 PM
Pat,
For be it for me to disillusion you, but 3/16“ equates to a tad under 4.8mm. :(
Jim
Thompson21380 - Jul 15, 2018 at 10:51 PM
The nearest that Eileens Emporium do is Plastruct TBFS-8 1/4” O/D which has an I/D of 4.9 mm as against 4.763mm which is 3/16“. So that is fairly close, but might be a little oversize.
The other thing would be to look on Ebay to see if you could find some Nylon or similar material.
Bob
Davenport20954 - Jul 15, 2018 at 11:03 PM
On a recent visit to London I popped into the 4D Model Shop (in traders). I guess it is really aimed at architectural model makers but the range of material were extensive; never seen so many plastic and metal sections; as well as sheet,material.
They do a 7mm plastic tube with a 1mm wall (5mm bore) but that is not quite the size as pointed out by Jim. (would probably halve it for posting). Depends upon the application; split axles?
David
Jim Snowdon - Jul 15, 2018 at 11:06 PM
Bearing in mind the need to leave clearance for the adhesive, 4,9mm bore might well do, plus ABS, which is what I believe the Plastruct tube is made from, is an easier material to glue than Nylon, which is impervious to any adhesives that are likely to be available for amateur use.
Jim
SimonD - Jul 16, 2018 at 12:57 AM
I recently made a set of split axles, using the method proposed by Steph Dale.
Essentially, drill longways through the axle, drill a cross hole of smaller diameter, degrease, and insert a short length of 2mm pultruded glass fibre rod, coated in the slow-setting epoxy resin of choice. This is centred by inserting oiled screws at each end. Air and excess adhesive will escape through the cross hole. It’s a messy business, so wear throwaway gloves.
Once the epoxy has gone cheesy, slice the excess & dribbles, etc. off. When it’s fully set, turn a groove (or two) through the steel, check for isolation, and then fill the grooves with more epoxy. When that has set, clean up as needed.
The advantages of this technique are the very simple machining, (pretty much any size hole that’s bigger than the rod and smaller than the thread ID, and pretty much any “V” or fine parting off tool) and that the back-to-back and quartering are maintained.
The disadvantage is that you ideally do need access to a lathe - though if you were determined and careful, a vice, electric drill and hacksaw could work.
Link here http://www.euram-online.co.uk/tips/splitaxle/splitaxle3.htm
Looks like the project has stalled, but the axles & wheels are here \\http://www.rmweb.co.uk/community/index.php?/topic/119828-another-beyer-garratt-0-4-4-0/?p=2636951
Hope this is helpful
Simon
Buckley10339 - Jul 16, 2018 at 6:48 AM
Yes Jim got it wrong.no idea what i was thinking off at the time.
Pat.
druiett23483 - Jul 16, 2018 at 8:19 AM
Many thanks to you all,
Yes you've described what I found on my google searchings, Thanks Simon, Stephs method works a treat and ive done two sets of driving axles that way, cut, glue, cut ,glue and no lathe was used just the trusty vice and saw, but works very well indeed, so simple and effective… Ive just got a couple of cast trailing wheels to deal with that need a sleeve to rejoin the axles and give the split effect.
Thanks for the message Rob, Im just going to reply,
But 4.9 seems the closest diameter available,
But thanks everyone
best Michael
DLOS - Jul 16, 2018 at 8:54 AM
Ah, indeed but not much new under the sun 
See also here in Gazette November, 1998:
http://www.gauge0guildarchive.com/gazette_archive/Vol14-1/files/38.html
David
druiett23483 - Jul 16, 2018 at 9:29 AM
Thats interesting David, thank you for sharing. I have to say I found this method
http://www.euram-online.co.uk/tips/splitaxle/splitaxle.htm
so easy. No lathes or workshop needed, just a vice, Dremel, and saw and file and glue. It maintained the strength and quartering of the wheels, and is strong and solid . Splitting the axle without it being in two separate parts.
StephDale - Jul 16, 2018 at 10:41 AM
David,
I've not seen that article before, but do acknowledge that the split axle pages on my website are not generally 'novel', even if I have tended to offer my choice of refinements!
It's just aiming to be a one stop shop after receiving so many queries when I was on the Technical Committee. I'd often be talking to people about split axles and get the response of “Nice idea, but I haven't got a lathe…”. So my response became “Well here's three ideas that don't need a lathe…”.
Incidentally, and not covered on my website, I do sometimes use an epoxy-insulated hardened silver steel pin through the centre of the axle rather than the GRP rod if I think there are likely to be any really odd bending moments (when used with Delrin chain drive, for example). The problem with the method is the level of accuracy required in setting the length and position of the centre pin which can't easily be overcome if either are wrong. When I work out a way to make them repeatably, I'll write that method up too.
Steph
DLOS - Jul 16, 2018 at 11:06 AM
Steph, I think we all 'invent' ways of doing things as we go along, making refinements, only to discover that it's mostly been done before. I wasn't trying to claim originality either, just offering a variation on the theme. As a professor once said to me when I thought I'd come up with a rather neat solution to an analytical problem “That's a good idea, David … and, like most good ideas, it's been done before!”
Despite what it says in the archive listing about my piece “Method for making split axles. A method of making these without a lathe.”, I think that it would be rather tricky and that the method that Forum article gave in their http://www.euram-online.co.uk/tips/splitaxle/splitaxle.htm is a better bet for those without access to a lathe.
David
Tomlinson5811 - Jul 16, 2018 at 11:09 AM
Steph, I found your type1,2,3 page by accident whilst searching for a method of insulating axles with squared ends. I found them very interesting, especially Ed Whalley's type 3. Even the type 1 was different to the method I was familiar with, as it offered an increased surface area for the glued joint. Cheers.
I'd previously created split axles with plain ends for some 48DS wheels. These were 1/8”, connected using an insulated steel pin to 5/32“ stubs which were then turned down to size. The tiny gearbox was by Exactoscale, but I'm glad to say that the introduction of delrin chain has made things a lot easier. BTW I would use the same steel pin in your type 3 rather than the grp.
