Here is a list of all the postings David Paterson 4 has made in our forums. Click on a thread name to jump to the thread.
|Thread: Apologies for my manners|
I have just managed to dig into my profile on this site for the first time in a long while, and found a number of PM that I had not unpacked. Please accept my apologies for not replying to your offers of assitance.
|Thread: Units of measure in Gear cutting|
I have been re-reading the workshop practice gear cutting book with a view to actually doing this.
One of the tables describes the dimensions for the button tools for creating cutter profiles. The dimensions used in this table are 'Ins'. Can anyone help me identify what these are please?
clearly they are not inches. Elsewhere in the book there is some advice the 1/4" material is sutable for maiking most small cutters - this would appear to be specified as '4' in the table, but any scling from that seems silly.
happpy christmas to the lot of you
|Thread: Visiting UK from Aus|
Good morning all, and sorry that it has taken so long for me to get back onto the net and thank this community for sir friendly advice and input.
i had a great month and several stops with engineering flavour.
i did spend a somewhat damp day in Basinfstoke at the traction rally. Excellent welcome from all, a short ride (actually my first) and good conversation every time it stopped. The indoor exhibition was also fun, and very social.
the following day I spent many hours in the technology museum in London and looked at both the team galleries and the clocks. The big mill engine was running and the two engineers very friendly.
other highlights were the Falkirk wheel, a full size engine near the Dalwhinnie distillery ( it was running and I only guessed it was coming from the people standing waiting on a bridge over the track. Most amusing was the conversation about the fires it caused running in summer - that is unbelievable to an Austrailian.) and finally a walk up the towpath beside the lock stair in Bath.
overall, a very good selection and top people everywhere.
Thanks, everyone for all of that information.
the museums look good for a day, and it looks like I will have a day off before my wife arrives to get to Bassingstoke. Looks OK by train from London. ( this is always a challenge - Canberra doesn't exactly have a train system, and the busses take longer than the pushie, so public transport is always an unknown)
wife gave up camping in December after getting caught in a snag on one of our rivers, don't blame her really, but is always good for a tramp in the hills.
top it all off, I have a 10 yr old visiting apprentice this afternoon - life is good.
i am visiting the UK over April for my first holiday there.
starting in London, the rough plan is 12 days anticlockwise via Suffolk ( wife's family- she emigrated at 6 and has never been back), Edinbourough, a distillery (fond of Oban but not exclusively) a couple of days in the southwest (bath & Stonehenge) and finishing at Hampshire.
would like to see/ experience some British model engineering while there.
|Thread: Is it model engineering ?|
do you rememebr the sketch from Blackadder about how much ground had been captured in the last campaign?
CAPT Darling had a model of the captured terrain about the size of a dinner table.
Asked about the scale, he replied 1:1
Good show, just introduced my teenagers to a bit last night. they loved it.
Edited By David Paterson 4 on 20/11/2012 06:57:19
|Thread: Drawing Projections|
I read this thread when Wolfie posted and didn't know what he was getting at - not struck the problem I suppose.
Just recieved a new copy of ME, and there on the bottom of some plans were these symbols.
now I have to go back and see if i understand them. - this board keeps finding more interesting things I don't understand (yet)
|Thread: Making Eliptical rod/tube?|
If I were doing this in Wood, it would be very simple. done between centres with interrupted cuts and two centre points at each end being the foci of the ellipse. round the final corners with a strip of emery. Ths is done all the time for 'freehand' oval cross sections, but if the centre points a re measured and the depth of cut controlled is pretty repeatable.
How would this go in metal?
Its OK for a brass band, but you won't see all that many silver plated instruments in other forms. One of our really good local companies has a service stripping the shiny lacquer from instuments to get the 'tone purer'. Takes on a nice patina after a while, but that could be just in context with dark bars as venues.
Military likes sivler so you can polish it - noting to do with the sound.
|Thread: wood turning|
The local woodworking show used to have a large display of this stuff - big pole lather, crosscut saw, and froe. All looks like hard work.
The fun bit for this hobby - if the model engineers sneer at 'brown stuff' for lacking precision; all these traditional technologies really only worked on green timber, and design specifically catered for the shrinkage as it dried. good example is the stretchers between chair legs had a flared tennong on the end and were fitted to a mortice that was bigger at the bottom of the hole. As the wood dried the stretcher was secured with a 'shrink fit'.
pretty cool stuff.
Richard is a good bloke - lives near here - and his books are invaluable.
Most wood turning is pretty freeform just because the wood itself is unreliable. If you want a cylinder to be concentric, then use of a skew or gouge may cause issues as the bevel runs on the previously cut surface - effectively the depth of cut is relative to the surface rather than relative to the lathe!!
While a scraper will not give the same finish, it is much better at referencing depth of cut from the tool rest.
There are many safety consious turners who will not go near an old file. The critical point is that if the distance between rest and work is too large (>10mm) as it often needs to be for curves, there is real risk of a catch and breaking the file. followed by ramdomly fired bits of iron.
You can easily make a very good scraper from a piece of HSS 25*5(or6)*200. grind a30deg bevel across the one end (you may wish to angle this at about 15deg to create small undercut areas but I havent needed that).
Grind a tang of about 75mm at the other end an fix a handle. handle needs to be the length of your forearm - some like them longer.
In use, the best finish from a scraper is obtained if you push up a burr after sharpening. In HSS this will require a very firm push with a piece of round HSS. the wire edge from sharpening is not really strongenoug to last.
I have two made this way, the other has a gentle curve and is OK for hogging, bu not for getting a parallel finish. Some people prefer high-carbon tool steels rather then HSS as the burr is easier to achieve and there is a view that these have better wear resistance.
|Thread: Running in|
Thanks Ian - I am scouring the shops for suitable bits of SS to start me off - funny that design can be driven by the availability of a single component.
The local turkish cafe has some cups on the table that might work (used to hold single-serve sugar - what a waste); and the camping store has some stainless drink bottles that have really parallel sides but these start at $16 each and i am being cheap.
|Thread: hacksaw blade mounting|
Blade backwards for coping saws for same reason, particularly through thick material, haven't though about a hack saw.
|Thread: Running in|
have you a photo of that Beam stirling?
can you describe this bit of steel you found in a battery?
|Thread: Steam engine timing|
What I really meant to say (so as not to hijack this thread) was that looks like I now need to look at the timing for the engine if I intend to run on Steam regularly.
I have been having my first serious go with steam aver the last week or so. I thought the spray from exhaust was just me. (built the engine a bit over two years ago and have been fiddling with the boiler forever! **LINK**
I did take a short video of the run, but have been experimenting with the firing system. Started with 3 wicks, but last night think i got a first 'successful' effort going with vapour.
Now that I have a burner, will sort out a fuel tank so everything doesnt stop after 15 minutes. prototype tank is a small boot polish tin with a spigot silver soldered in. If that works (was very cheap) I will graduate to a bird bath.
|Thread: Firefly .46 crankcase|
Like the photos. In the second you caption 'clockiing true'.
Is this to position the centre of the face for drilling, or to align the axis of the block true with the axis of rotation?
if the latter, how? - seems like a good idea and an tis point of learning I sort of rely on having the ends parallel and tappping the block onto the face of the chuck to achieve this. Looking for a better approach for stuff that is neither round nor long enough to take readings from two points along the length out from the jaws.
|Thread: What are we building?|
Only a bit related to this thread, but the inclusion of clock plans over the last few magazines has be intrigued. Can anyone help me find a source on how to actually build this thing?
|Thread: Silver solder problems|
Had the same prob on my boiler and mucked about with flux and pickling and 3 different melting points for the solder.
In the end it was all about heat.
I created a small hearth with three heat bricks from the BBQ shop; one flat and the others closing the back left corner. this reflects a lot of the heat back onto the job. I made sure that the heat sink was warmed up befor bringing the solder site to temp by moving the torch around on the large bit of metal first. I dipped the rod in flux before applying, brought the solder point to final heat quickly and then ''moved the heat" (rather than spot heating) to points where the solder did not flash.
This works most of the time and then I smile
What is this stuff, and how do you get it?
Seems like a good idea to me and how does it handle compared with brown paper?
I have trouble finding thin paper so all sorts of bodgies.
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