Taig lathe cabinet - drip trays and panel beating

This article covers the construction of the drip tray (first and second attempt) and touches on the panel beating methods I used

As mentioned in the article regarding the frame, the objective of the lathe base was to have a substantial piece of metal which was thick enough to support drilled and tapped holes, magnetic (for use of mag-based tool stands), and to help dampen noise. Thinking I could do this by building a drip tray out of 4mm steel, I made a tray by scoring and cutting the sheet, and then bending and welding it up.



Figure 1 - pieces of 4mm sheet scored and bent



Figure 2 - 4mm sheet welded up to form drip-tray #1



Figure 3 - resulting drip tray from 4mm sheet - distorted and not flat

BIG PROBLEM - the resulting tray buckled during welding and would not provide a flat base. no amount of cussin' or hammering would fix that. - on to Plan B.

Plan B was to use a thinner metal to make the drip tray, and then use a separate sheet to form the solid base floor. The frame was built to support this design, and the base sheet cut and fitted. From that sheet, all other measurements for the drip tray were derived.

The drip tray is made from colourbond "sign-white" - a thin sheet metal coated to prevent rust (some kind of zinc-aluminium coating) and coated in a bonded white paint - it's used by sign writers to make shop signs - hence the name. The other side is a pale grey colour, and this became the visible side since it was easier than trying to remove the old vinyl lettering from the white side.

My source of sign-white is a number of discarded signs which I obtained soon after moving to this town. The frames for the signs quickly became stock for building a myriad of doors, shelves, etc, and the panels have become door skins, guards, and a number of other tasks. This lathe drip tray commenced the use of the last full sheet.



Figure 4 - commencing the folding of the drip tray (#2) - forming the wired edge

Since I don't have a pan or finger brake (yet another project yet to start) , I improvised using tube and angle iron clamped together (often the tube was one side of an old table frame). The "mallet" was a piece of pine timber, and a piece of 2"x 1/4" flat bar was used as a flatter to help crisp up the edges. I formed up a wire edge for the edges of the tray where hands would touch by folding the sheetmetal around a strip of 3mm x 25mm (1/8" x 1") strip and hammering it flat with a mini sledge hammer.. after everything was folded up, this gap was then closed up to complete the wired edge.




Figure 5 - completed drip tray with wired edges for safety

This method of folding was used throughout this entire project - drip tray, drawers, trays, control cabinet - all fashioned with bits of tube or angle iron, 3 clamps, a piece of timber (with or without a flatter), and a pair of ear muffs to drown out the noise.



Figure 6 - completed drip tray and back board


Figure 7 - Rear view of back board showing overlap

Next article will cover the swarf gate and accompanying swarf drawer.
Still to come:
Drawers, electrical circuit, "home made" switches, control panel

Taig Lathe Cabinet - Motor Mount and unloader

I'll start documenting the build of the lathe cabinet using those photos still on the card in the camera (the other photos will have to wait until after the PC is rebuilt)

The Motor Mount
The original lathe stand used a jackshaft mounted on a wooden slide-way for a clutch, and speed control was limited to the cone pulleys on the motor/jackshaft - and then the standard Taig 6 speed cone pulley.

The new motor system would have the motor speed controlled by a VSD (Variable speed drive) giving infinite speed control over the range of 0-100%.
I still wanted a clutch (unloader) so I looked at various designs used by others and cobbled up a version of my own.

The belt tension aspect of the motor mount is loosely based on a design shown on Nick Carter's website. (www.cartertools.com)
His design uses rods for alignment, and a threaded rod for adjusting the position of the moving member. My design uses slots cut in the mount for alignment, and a threaded rod for adjustment.
The basic structure is made of two pieces of 50x50x3mm angle iron (2" x2" x1/8") welded together to make a channel 100mm wide and 50mm deep (4"W x 2"D). the length of the pieces is approx 200mm (8")

I then cut 2 pieces of 50x50x3mm angle iron at around 300mm (12") long and cut slots about 12mm (1/2") from one edge. The slots were a clearance fit on standard 6mm bolts. (Slots were cut using drills to mark the ends, then 1mm cutting disc in between)

Corresponding holes were drilled in the piece made earlier in the description, and 20mm (3/4") bolts were tacked into place so the threads extended out through the slots.
End pieces were measured and made up to close out the end of the longer pieces, as much for stability, but also to support the threaded rod used for the adjustment.
The moving part is driven by a nut which was threaded in, and then tack welded to the underside of the moving part.Nuts spun on to the threaded rod, and welded in place became the thrust surfaces for the rod's action, and one nut was welded in place out the front of the unit for adjustment purposes.



Figure 1 - base of motor mount - sliding parts.

The pieces already described do not actually mount the motor, instead they provide a base which can be adjusted. The part which actually supports the motor is a hinged channel (cut from the side of some 100x100x3mm square tubing) so it actually 100mmwide, and 15mm deep.
A corresponding piece is fabricated from 4mm plate to sit atop the moving motor mount part made earlier, and to support the channel piece just described. The channel piece supports the motor by means of 2 slots cut in the channel at right angles to it's long axis - these permit adjustment of the motor position along it's shaft axis.

The channel is hinged onto the mount plate, and a cam is placed near the mount hinge to change the angle of the channel. The cam was built by cutting an approximate shape from 4mm sheet, then  tack-welding a 15mm wide strip of sheet around the cam surface for wear reduction. The cam has a position where the "lifting effect" is stopped - this is the position where the motor is tilted back away from the headstock of the lathe.


Figure 2 - the built up cam which tilts the motor mount channel.


So the overall structure is:
the motor tilts forward and backward within a range of motion governed by a cam (35mm = 1 1/2")
which sits atop a sliding mechanism which adjusts belt tension over a range of 75mm (3")
The motor can also move along it's shaft axis by 25mm (1") via the slots its mounted in.

The cam is operated by a wire lever about 250mm (10") long located well out of the way on the LHS of the cabinet.


Figure 3 - completed motor mount assembly

A standard steel ruler pinched under one of the slide nuts was used to test the range of the tilt mechanism



Figure 4 - Motor mount system in the unloaded (belt tension released) position.

The recorded range of motion was approximately 35mm (1 1/2") between unloaded (no tension) to the loaded (tensioned) position.



Figure 5 - Motor Mount in the loaded (tensioned) position.

Why have the facility to drop belt tension via the lever?
#1 - ability to leave the lathe when not in use with the belt un-tensioned to prolong belt life
#2 - easier changing of positions of the belt on the 6 speed pulleys
#3 - less chance of driving the motor when moving the spindle by hand (new motor is a PM DC motor which would act like a generator if I spin the chuck by hand)

So based on this design whenever I change the belt, I would place the belt on the appropriate pulley range and push the lever up into the "loaded" position.
I would then use a 17mm socket to adjust the threaded rod and move the sliding part so the belt tension was where I wanted it.
Then I would use the lever to reduce the loading, and adjust speed ranges accordingly.

In testing, I have found the flat section on the cam is sufficient - I can "feel" it click in through the handle, and the tension stays constant during use.


Next couple of posts:
I have photos of the frame construction, basic sheet metal work, and the construction of the control panel i can access. It doesn't cover much of the control electrical system, but does cover the fabrication of the switches, and the panel-work itself.

Hose suspenders - Part 1

OK, I'll openly admit it, I'm not a tradesman... I'm a dabbler. If you haven't already noticed it, some of what I show in these pages are mistakes, errors, and substandard welding. It's not from a lack of wanting, just a lack of training. Half of what I put these pages up is to show what can be done, the other half is to show what shouldn't...
I was once told that a Wise man learns from the mistakes of others - learn from mine. (you won't have time to do them all yourself!!!)

I offered to make some "hose suspenders". These are used by firemen for securing hoses running up ladders during structural fires. The suspender comprises two main parts, the first being made of steel, and resembling a large fish-hook. A sketch of it is shown on the welding table below....
The one I saw (to take dimensions from) had been forged from 3/8' (10mm) rod, but since I haven't built my forge yet, I figured I'd built these from welded pieces of steel. The ring at the bottom would be made from small pieces of pipe, and the two "hooks" would be made from 3/8" rod.

I obtained some 3/8" rod from the workshop, but all that was available was square rod, not round. I decided to make the "round hook" first by bending the rod around one of the pipe offcuts left over from Bender's legs. I welded the offcut to a scrap of steel as a jig.

The above photo shows the steel in the jig (Mk1) - all chalked up for the photo, and the arrow pointing the direction of the bend.

Cold bending 3/8" square rod was fairly easy, but getting it to conform to that curve was not easy. Sure I could have threatened it with the hammer, or swore at it, but I needed a better plan.

Mk2 jig basically added a "slipper" to the bend - a 1/2" (13mm) rod was welded in the centre of the pipe via a hole and plug weld, and a pipe handle was made to hold a slipper against the rod being bent. The slipper was nothing special, just a 1" (25mm) piece of pipe dropped over a 1/2" (13mm) rod.

The slipper keeps the 3/8" rod against the former in the jig through the entire rotation of the slipper pipe. This forces the rod to bend just as tightly all the way around the 180 degree turn.
The photo below shows the Mk2 jig, with the pipe (and slipper) at the commencement of a bend

about 20 degrees through the bend, I would place the larger yellow pipe on the slipper pipe as a handle to increase leverage, and then complete the bend

I found it easier to place my body between the end of the rod, and the pipe handle, using my hip to guide the rod stock, and my hands to guide the pipe. Sounds awkward, but it was actually easy, and quite quick. Once the rod was bent, I aligned it with a mark on the jig, and cut it off with the grinder, and started again. All up, nine hooks were made in about two hours including making, and remaking the jigs.
Part 2 will cover why the same solution failed for the other hooks.

Foundry "Robot" - part 1

I built a furnace/ foundry for casting in Aluminium, Brass, and Bronze. (more details on that later) - to manipulate the crucible, I looked at a number of options, but this.. is what I ended up building and using.
It's all home construction - tools used was welder (arc), grinder (grind, and cutoff discs), and miscellaneous hand tools.

The "robot" is not a real robot (powered with a form of control), but rather more a mechanical machine which I control. (yes I won't split hairs over semantics - compared to the robots at work, THIS doesn't count)


The distance between the operator, and the gripper is 3.0m (10'), and there is no lifting required, except to assemble and relocate. All "lifting" is done on a counterweight system, and my own body weight is used to my advantage.
Following over the remainder of this page, and the next pages will be photos of the robot, and text explanations of the mechanisms. All steel sizes are as much a reflection of my stockpile, rather than calculated engineering recommendations - in fact everything I write should be taken with the usual legal indemnities/ waivers applied. - in other words, if you don't know what you're doing, and aren't prepared to wear the consequences, don't use anything I've done help you qualify for a Darwin award.

Overview of the "robot" - open gripper facing camera.
The crucible is on the ground in the shot above - the pipe is 2 1/2" OD for the main beam.
Now some detail - working from the bottom up...
The spigot joint (Slew)...

The spigot joint is made of three lengths of pipe, two the same diameter, and the third a slip fit inside the first two. The bottom pipe, and the central (internal) pipe are welded together, with a washer across the top of the internal pipe. A steel mouse ball is placed on top of the washer, and the third pipe is dropped over the top of the whole lot. Inside the third pipe is another ppe with a wisher, so the bearing surfaces are the two washers, with the mouse ball between them. The three bits of pipe form a spigot joint for rigidity, and the ball/ washer bearing for friction reduction. The legs on my robot fold up, but that's a personal choice.



The top joint is complex - please bear with me.
On the top is a "sleeve" joint, complete with bearing shells (made from pipe halves), to provide a rotational, and sliding joint. The photo below show the bearing opened on the LHS and the upper bearing shell moved to the left. Obviously the whole bearing assembly is greased up in use.

The shells are tightened via the wingnuts at the lower edge of the photo, and normally there is a dust cover over the entire sleeve joint.



The other major axis of movement is the tilt joint located under the sleeve joint. It's hard to photograph, but it's simply a short length of pipe mounted across the top of the spigot joint pipe, and a slip fit bar running inside the pipe, welded between two "cheek" pieces (shown as yellow in the photo below.


Part 2 will show more of the joint, and focus on the gripper