Here is a list of all the postings John Pace has made in our forums. Click on a thread name to jump to the thread.
|Thread: Work Holding For CNC Milling|
Should have said pinking shears ,here they are ,one of the first
A little off topic with this part but for those of you who may have read the original article an opportunity to see the end result.
In the original article the subject matter was the production of a pair of
I use these simple fixtures for these sort of jobs seen in an article
|Thread: Bevel Parallel Gear Blank Roll and Offset|
On page 111 of the gear cutting book about three quarters down the first
I see from your later posting that you have a 15 hole plate ,
The sizes of the gears at the large end do not influence
|Thread: Soba rotary table|
Posted by Neil Wyatt 14/03/2019 22:09:51
Good idea John, a bargain basement (<£5) angle grinder 36-tooth
Not so sure how that a mating worm could be made to work
The photo here shows the gear being cut ,this gear was made
The position of the centre distance of the hob needs to be
|Thread: Mixing Gear Module?|
Myford .8 module change wheel set and Warco Gh 1000 1 module change wheels ,both keep within the machine covers.
|Thread: MT4.5 sleeve|
Here is a drive unit that i made ,toothed belts work fine for these and don't leave a chatter pattern on the work and provide a positive drive.Three speed gearbox and variable speed motor gives a drive speed from 20 to about 700 rpm.
|Thread: Machining cork!|
I you have ever used some silicone sealant the tapered nozzle that is on the tube always has some left over sealant inside that sets inside , pull it out and you have a tapered plug of silicone ,cut it as required to form a suitable silicone cork.
|Thread: 4th Axis for Sieg KX1|
A 4th axis is an essential accessory and opens up what is possible to do.The compressor wheel on the left is milled from 2014 t6 aluminium 68 mm in diameter ,the one on the right is a bought cast wheel 66 mm dia for a KJ 66 model gas turbine.
Edited By John Pace on 04/03/2019 09:38:33
|Thread: Warco Rotary Table - What Grease?|
Edited By John Pace on 25/02/2019 09:55:36
Rocol Tufgear universal open gear grease is a sticky grease that retains it's position when applied ,RS sell it part no 388 8465 may be cheaper elsewhere .Good for changewheels etc very messy.
|Thread: Model gearwheel pump|
Some photos of a geared oil pump for a machine coolant
|Thread: Quorn Castings|
Posted by Emgeere"> 12/02/2019 10:04:39
Nice looking Quorn and a very well planned nest of swing out
drawers, is that your design ?
When grinding along the flutes of milling
cutters I thought the cutter should be ground
on the periphery of the wheel but above centre to
provide back clearance, how do you grind flute back clearance ?
Just a matter of space saving ,some angle iron supports hold
the wooden trays on a single strut.
The photo shows in the foreground a post that is secured to the
table, this is a zero reference to the workhead axis,using a
dti the tip of the cutter is set to a zero position using
Looking at the photo rotating the cutter anti-clockwise
increases the angle from zero to the desired amount .The
grinding wheel is at a shallow angle relative the the work
axis ,as can be seen by the black line around the edge the
point of contact is small as it should be.
Early on when i first made and used this machine this is
how i would set up,now i use the same basic method but grind
first the secondary clearance. The Quorn book seems to show
the primary clearance as 6 deg ,in a Dormer handbook this is
shown as " Clearance on body teeth , this varies progressively
across the range from 10 deg on smaller diameter tools to 5 deg
on the largest diameter . Secondary clearance ,this is 15
deg across the range".
Setting 15 deg on the machine ,20 motor steps = 1 deg ,rotating
the work shaft 300 motor steps sets the 15 deg.
When the cutter is ground, the secondary clearance can be
measured on the machine as in the photo diagram ,since from
this the true angle is known it is a simple matter to rotate
the cutter to set the primary clearance angle.
Page 94 of the Quorn book makes reference to grinding
on the periphery of the wheel.
Posted by Derek hall 1 11/02/2019 13:01:12
I did my apprenticeship in 1974 to 1978 and in the stores in the
first year they had some ME magazines, and in one or two issues
was the description of the Quorn...one day I thought, I want to
make one of them! 45 years later I got the castings!..
I hope that you stick with it.The Quorn is an enjoyable thing to
build and when it is done you will have a very useful piece of workshop
I built mine 30+ years ago and have added to it over time.
The problems are all the same the friction of the workhead and also
|Thread: The Diamond Tool Holder|
Posted by John McNamara 7/01/2019 13:23:07
Hi John Pace.
GMTA I made the same toolbit using the carbide shank from a
I milled a piece of key steel of the correct size and silver
I don't use the supplied fixture to sharpen the toolbits,some while ago
Having 20 ground ends if one is dulled it goes in the grind box and
The carbide tips that are ground similar to a CCMT shape only need regrinding
I silver soldered this 1/8 inch carbide shank into a suitable size square piece,the edge is milled out about half the diameter and the piece soldered in ,it seems to work best if left as a round shank.The round piece fits neatly between the clamp.
The one on the left is ground to conform the the square shank ,because carbide chips easily when ground to the acute angles of the diamond tool a shallower angle is needed at the top and both the sides need a little grinding for clearance.
Useful for harder materials and maybe cast iron.
|Thread: Occasional usage Sand blaster|
I built one of these sandblast cabinets 20 + years ago from
It looks as if the vent on the back of the bin blaster has a
My own cabinet is sealed and vented externally.
Rubber gloves 24 inch in length are avalable from J&L
|Thread: Small Milling/Drilling Spindle (again)|
Posted by ega 14/01/2019 10:58:45
In the introduction to his 1997 book Harprit Sandhu invites corrections.
I bought the book partly because, having faced the challenge of building
Edited By ega on 14/01/2019 10:59:05
The outer sleeve is bored through for a close fit for the bearings,in this way
The shaft is made with bearing seats this gets rid of the bearing spacer tube
The two sleeves seen in the photo, the shorter one is eventually loctited into
The two screwed end caps similar to the Quorn ,the front one traps the
Perhaps the biggest advantage of constructing in this way is that all
|Thread: Holding work on the cross slide|
I had a similar problem with my Warco lathe .I made an add on plate the full length of the crosslide just over an inch thick ,it is held with six 6mm cap head bolts ,holes for mounting parts are drilled as needed.If your lathe is similar to mine about the rear third of the crosslide is little more than a cast in cover and is quite thin in section so careful placement of the bolts is required.
The topslide mounting ring will most likely be too far from the centre line of the machine to be of any use in holding work in any event to fit longer tee bolts you will probably have to remove the crosslide.
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