Member postings for Geoff Rogers

as per Duncan, I am sure Polly will be able to provide a Gordon Smith design valve that will work.

Geoff

KWIL,

the cylinder is single acting short stroke and made from SG cast iron. The piston is two part and fitted with a heavy section O ring. The piston/bore sizing is such that an anti-extrusion ring is not needed. The O ring is about 55mm OD and about 5.4mm section.

I have used the cylinder to close up to 1/4" steel rivets (the largest I need to close) and it has seen a lot of use so far with the rear wheel strakes and front wheel construction (I am making three engines). To date, no leakage and nothing broken. The dollies are made from mild steel case hardened at the business end .

Geoff

I form the rivets in two stages; one to set and a second to form. I have found that the 'set' operation is most beneficial for two reasons, firstly to make sure the rivet fills the hole and secondly to stop, or at least reduce the chance of the rivet cocking over during squashing resulting in a very bad head. Rivet and I.

Geoff

hi Andrew,

I have a pressure gauge fitted to the hydraulic setup and I take the pressure to about 3000psi for 3/16" rivets. For the cylinder I have made these pressure equate to about 5.3 tons. This gives the formed head as shown in the photos - unless it goes wrong, that is.

Geoff

hi Paul,

the rivets are 3/16" steel round head and 3/4" long. The spokes and rim are 6mm, leaving 0.277" for the head. More or less equal to the 1.429D setting allowance specified for a formed round head.

Geoff

I have uploaded some photos showing how I am riveting the spokes to the rims for the 4" scale Burrell traction engines I am making.

The photos show the hydraulic cylinder used and the resultant rivet heads. using this tool I can use the as-supplied rivet head on the outside and from a head on the inside, where it is less visible.

Hope this is of interest.

Geoff Rogers

Michael,

what do you mean by 'engineering ability' ?

Geoff

may be worth checking the spigot as well.

regards

Geoff

thank you Steve,

both files are most useful

In case anyone is interested, I have converted Steve's excel spreadsheet to MathCad (Prime, but can easily be produced in a version 15 option). Why - I just prefer MathCad as I can see all the formula.

Per Andrew, except I then give the not-to-be-machined regions a coat of paint. Makes then nicer to handle and easier to clean.

regards

Geoff

(currently in Germany for a rail impact test)

as JasonB says, corrosion would also be my main worry. Some aircraft grades of aluminium may be ok, others most definitely not.

Steam can be a very demanding fluid.

I would go with the LBSC option or use 1/8" copper rivets. But either way, I would discuss it with your boiler tester first, as he (she?) will have the last say.

Geoff

excellent!!

Andrew,

is it a workshop or a factory you have for making your traction engines?

thank you Roderick for the tables in the other post. just the job.

6 microns - easy to work to if you happen to have a couple of millon pounds worth of kit, but not what you would find in the avearge shed.

Geoff

hi John,

I am sure you have said before, but which gear?

Geoff

I found the programme as expected, but it was interesting.

I now know that mine winding engines have a connector rod rather than a connecting rod - so I learnt something.

The rivets on the 'barn engine' boiler looked nice and shiny so it must have been ok, unless it was a dummy end of course.

thanks JasonB

lets hope it has more focus on the content rather than the presenters.

bright and shiney so it can go back into the house after running, I suppose.

I have drilled holes in my Myford and cut/bent spanners for restricted access.

As with Andrew, I am using 3D CAD (TurboCAD Pro) to draw up the 4" Burrells I am constructing and I have found the need to 'refine' parts to make them fit properly. The CAD program made designing the hyrdraulic rivetter for the rear wheel strakes straightforward. So I find a CAD program is most useful and does not encroach on metal time, quite the opposite.