Here is a list of all the postings jason udall has made in our forums. Click on a thread name to jump to the thread.
|Thread: What bearings for a submersible wheelchair?|
|Dry bearings would be the way to go.|
Because any kind of lubrication will upset risk assessment bods.oil or the hint of a risk of oil ib the pool .Even PTFE built into plastics .. would be called a lubricated solid..just avoid that discussion So choose a self lubricated solid. Though avoid leaded bronze or similar...
Edited By jason udall on 05/10/2018 21:36:00
|Thread: D bits|
|I know it's obvious but check your drill shank is the desired size ....|
|Thread: Tool i/d and Mitutoyo vernier advice please.|
|If that dial caliper is an after market mod then it must be common...I have seen one with the same Adulteration...on inspection the finish appeared factory fresh on the cut off bits|
|Thread: What type of glue to use...|
|I would go for "Pritt" or any similar paper glue...|
Soak in water to remove..paper and glue
|Thread: How can I drill a deep, non-standard, small diameter, hole?|
|Can I suggest |
Wire of proper what is the diameter diameter ..expoxy fill bush..letting wire set.
Apply current to wire allowing wire to heat..pull wire free.. leaving hole..
Some experiment will allow wire selection to leave a hole of suitable fit
Edited By jason udall on 08/07/2018 16:26:00
|Thread: Controller for a 3 axis lathe|
|Here's my two pence|
X axis on mill is front to back up axis is left right
Z is along the spindle
Lathes map these the same but less "arbitrarily"
X effects diameter through center line
Z length of part to and from headstock
Y axis is generally interpretated as tool height not generally used that way
The C axis is also controlled for "pseudo"y axis where a plane x' -y' is wrapped around the part in a cylinder using C axis and z ...and X axis being z' or depth
Now your control may or may not understand all that as must your CAM Software...
A milling control without a turning mode won't be able to convert all those axis /coordinates for you..but I have in the past used Excel is post process milling engraving g codes to "around" a cylinder g codes..
As to your compound curves for pen handles...good luck..
Maybe consider ppnot a CNC lathe but an egg lathe...whole different hobby
|Thread: 'Why Projects Fail ...'|
|Why dp projects fail?|
The aforementioned law zero incomplete definition of target
To mention one infamous project
.project DEEP THOUGH. .purpose. .to calculate the answer to the question Life the universe and everything
..just look how that turned out
|Thread: Channel 4 (UK) tonight Sunday Jan 7|
"Great to see the initial failures not being hidden from the cameras and I expect to see tantrums, resignations and huge arguments in the following episodes"
And how dull for the telly viewer would a carefully planned and executed build have been...no "drama" no "jepody"
This is not tv made for the likes of us ( what would be... we are generally in our sheds not watching telly)..its made for the mass audience with a hint at model train enthusiasts
|Thread: When is 9mm not 9mm?|
|Not just "ebay" and china..|
Once had to finish thousands of parts to square up stock to A)square section B) size..
Because bought in stock has tolerance.. (fortunately -0 +0.14) pain :'(
Edited By jason udall on 04/01/2018 07:23:19
|Thread: Bevel ?|
|I guess this is a bit of a pointless ( though interesting nonetheless) discussion. ..drawings will clarify instantly the dimension. .|
But just think of this..a screw is fitted to a machine...and then for reasons it is removed put to one side..The hole is drilled through clearance and the screw replaced..with a nut at far end...that screw is now a BOLT....
yes I know drilling out and adding nut is bodgy but it serves to illustrate.
English (even technical- roll yer sleeves up and get on with it- English) shows its long history in the oddities fossilised into it....
|Thread: small baty bore gauge thread size?????|
|Ok thats a bust..it appears pattress screws are 0.6 mm pitch|
|M3.5 as I call them pattres screw ( holds light switch face plate to the square back shell in electric fittings)..|
Just a though if you have any about. .to trial fit. .
But from memory those are 0.5 pitch...
|Thread: John Stevenson|
|Seeing the positive can do attitude shown in the posts in "weldit where it touches" thread ,I doubt I can add much to that spirit .|
But the little I can add John .you can have it. .. get back and get us back in order.
This editor doesn't like my phones browser
Lets see if this works...if not look up ambiguous cylinder
|Thread: 3D Printed Threads|
|The actual extrusion is not circular in cross section. .|
The thickness is well controlled ( at least initially) but the width of the extrusion is somewhat controlled be the filament feed rate ( not confused with the nozzle movement rate in x,y,z)..thus you can extrude in one pass a ribbon 2-5 mm wide by say 0.1 mm thick..
The edges of the ribbon might (certainty ) not be square..but this geometry will depend on many things..surface tension , viscosity and the like , all dependent on extrusion temperature /material/infill among others. .a reasonable approximate would be semi circular of diameter equal to the layer height..
Some sagging occurs leaving the edge deformed from that simple shape. .effected by cooling profile. .
. Nozzle size has an effect on the minimum scale printed (outside radius) and wall thickness ( minimum wall thickness)
Edited By jason udall on 09/09/2017 22:48:52
|Thread: Effect of Tensioning a Boring Bar|
|Just a thought. |
Musicians adjust the tension in wires. ..to change the fundamental frequency.
If one were to get the note wrong. .you might get harmonically related vibration from tool and part. .being able to tune the tool to avoid this combination might prove useful. .
Btw have used solid tungsten carbide ground tools..these do the job when all else fails. .seems "solid" tc has a lower Q than steel
|Thread: Machining Tungsten|
|Also uranium is very poisonous( in a heavy metal way) . .much more so than lead|
|Thread: What are these stone sticks?|
|Op has it...soft and chalky...defo soap stone or "french chalk"... |
|Thread: Casting Sand still going wrong|
|Just a thought..I see no mention of draught angle on the patterns..I believe ( been a long time abd that with oil bonded) that a draft angle is required only 3-5 degrees but needed none the less..|
As I say been a while
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