Here is a list of all the postings Tony Martyr has made in our forums. Click on a thread name to jump to the thread.
|Thread: Lacquer or light oil?|
The local Museum is taking one of my model engines as a long term exhibit. It is a semi-rotary beam engine and much of it is in bronze and brass, painted and exposed. I am concerned about how the exposed steel parts should be prepared. The museum is fitted with dehumidifiers that run year round so I wonder if just a light oiling will be sufficient or if I should use some sort of more longterm preservative - any ideas welcome!
|Thread: Double Tangye valve attachment|
Thanks for this Jason
I rather feared it was something like your reply - but with only about 7 thou radial clearance between rod thread and hole the distance between the valve face of the cylinder and the centre-line of the valve rod is a 'bit critical'. The counter boore of 1/4" in the bck face must be the contain one of the locking collars/nuts.
Thank for your reply - Tony
The single drawing of the double Tangye engine I have doesn't show the method of attachment of the slide valve to its rod. The valve has a 1/8" hole through which the 6BA portion of the rod must run but I can't see how there is any vertical freedom of movement allowed so that the steam pressure seats the valve on its face while retaining fixed axial position on the rod. My previous engines have had groves in their top faces that housed cruciform ends to the rod - I must be missing something obvious!
|Thread: filling cast iron blow holes|
I have a 12"x12" cast iron engine base that, in addition to a couple of chilled hard areas, has a series of small 'blow holes' on one flank. This do not create a problem to the structure but don't look nice so I want to fill them before prime and finish painting - but with what? The base is far enough away from the working parts not to suffer any great temperature gradient but it would be embarrassing if bits dropped out.
|Thread: DM-18 Mill/drill failure|
Yes Martin, all the obvious problems have been carefully checked
given the total lack of outward signs I will blame the printed circuit because I'm a 'rude mechanical'
I have a DM-18 variable speed milling and drilling machine which has given excellent service for the last 9 years but this morning, while fly-cutting an iron casting I hit a chill spot and the machine was stalled. I banged the EM stop and no obvious damage was done but the machine is now dead.
The drive system has been checked as OK, the electrical feed is OK and there is no electrical smell. In side the control box there is no sign of fuses so I am at a loss to know what has failed - any ides welcome
|Thread: 'Why Projects Fail ...'|
Thanks for the comments which all raise a couple of interesting points:
Fourthly: The latest statistics from the USA states that: only 16.2% of industrial IT projects were completed to the customer's satisfaction and on time. Of the remainder 31.1% were cancelled during the course of the project leaving 52.7% that failed to meet the customer's expectations and/or were over-budget and/or late.
Edited By Neil Wyatt on 06/02/2018 19:07:11
I have a contract with a US based publisher and have just sent off the finished draft of a book provisionally entitled 'Why projects fail ..'
|Thread: 7 equi-spaced holes on a pcd - why?|
Thanks to all and particular to JasonB for the inclusion of the part section drawing.
I have a copy of the single Westbury drawing from Reeves which does not show the position of the cylinder drain hole which justifies the unusual flange hole distribution.
The drawing raises a larger point - how will we get the younger generation of engineers to follow in our hobby if these very poor imperial dimensioned drawings are the only design source material? I have spent my life involved with gearing and engines and have built a few models but even to me this drawing of the Double Tangye is more of an initiative test than an aid. I haven't located a copy of the articles that originally aided the construction. My interest in the engine was raised by seeing a unit at the Broomy Hill Engine site in Hereford - I'll go back on the next 'steaming day' and count the bolts.
I'm considering building a Double Tangye as my next project, in spite of a rather awful drawing on which I notice that the cylinder detail calls for 7 holes on the pcds of both ends. 7 holes seems to be deliberately awkward is there a reason for this due to a spacing clash that I've missed?
|Thread: Steam pipe insulation|
I need to create an insulated and painted steam line between a vertical boiler and a rotative beam engine which is to be entered into a local competition. My use of plaster of Paris bandage has produced a thermally satisfactory result but a horrible lumpy and pitted looking pipe covering. I am thinking that a smooth plaster using children's casting plater would be usable and the simply paint using the same paint used on the metal work. But will that stand up to the heat and expansion when running with steam?
What is the exhibition technique?
|Thread: how many 'one time' tools do you have?|
I have just bought and used, for the first and last time, a special 35mm cutter designed to cut the holes in a kitchen cabinet door for their hinges. This tool joins a select collection of tools used only once in my life, and theirs, to fulfil a vital role that I can't consider throwing out or selling.
The very long nosed circlip pliers used once in a gearbox rebuild, the right-angled ratchet screwdriver used once when stripping an engine etc.
I don't count jigs or tools I have made - I can get rid of them without a second thought but as for the bought ones, even after 40 years - I just might need one of them again
How many do you have?
|Thread: Small lost wax casting supplier?|
TonyI have been asked to refurbish a rather beautiful medical weighing balance made in the late 19th century . My main problem is that one of the hangers that sits on the knife edged arm ends is missing. Since we have its twin I know exactly how it should be formed. It is a small bronze casting rather too complex and decorative to be made by fabrication . I have tried to find a supplier, indeed I thought I had found one (Redlake?) but repeated emails have not even been acknowledged
Can anyone suggest a source, or at least a company that reads their emails?
|Thread: Source of hardwood base material|
Thanks for the help - through these replies I found Ockenden Timber which is a treasure trove of kiln dried timbers and is only 20 minutes by car form home.
I bought a slab of American black walnut - not cheap but exactly what I wanted and I resisted the temptation provided by their display of woodworking tools
I have finally run out of my stock of hardwood and need a engine base around 12x8 by 2 inches thick. The stuff I have used in the past was a heavy dark Fijian wood which suffered from water staining but otherwise looked good and was oil resistant. I have done the usual web search but have rather lost my nerve (!) so seek recommendations for this forum
|Thread: O rings - where to buy true inch sizes|
I am making the beam engine to the 'Mary' design which calls for three different sized O rings of imperial sizes. Although listed as 'true inch sizes' on the web site of Exact Rubber they are no longer available.
Can anyone guide me to a possible supplier - I have made O rings in the past from Gaco cord but never as small as two of the rings needed for the valve and piston rods
|Thread: O Ring material choice|
I am building a Beam Engine which is using O rings rather than graphite stuffing for the piston seal and those for the valve stem. The best supplier site offers rings of the correct size but with a choice of material which includes: nitrile, fluorosilicone, neoprene, polyurethane, silicone and viton. Which should I use for a low friction steam engine?
|Thread: cleaning off Stag jointing compound|
I've just started stripping my triple expansion engine down and have to deal with valve chest faces and studs that are coated with tacky Stag jointing compound.
Is there a solvent that I can use to clean these parts?
|Thread: Another thread question - Tractors|
Of course! - it is certainly coarser than the BSP and I had forgotten about NPT threads.
I have acquired a 1955 grey Ferguson tractor and need to modify part of the diesel fuel line by tapping a hole in the Kigass tank (a whole new story!). The fittings are the compression olive type and I thought the thread was 1/8"BSP , it is certainly the same size but a different tpi
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.