Home Shop Made Tools

[EdK]

[randyc]

(08-11-2017, 12:35 AM)Highpower Wrote: Not much going on lately I'm afraid but I did manage to crank out a pair of "Wright Rollers" a couple of months ago.

Beautiful work - I'm envious !!!

[randyc]

Collet system for Emco-Maier 8 x 18 lathe.  Cast iron backplate, bored while mounted to the lathe spindle then permanently shrunk to an ER-40 collet holder with the rear part sawed off.  Takes standard ER-40 collets from 1/16 to 1 inch with no gaps in coverage.
 
   
 
Temporary collet system in Sheldon 11 x 36 lathe.  Another ER-40 collet holder with rear portion cut off.  Holder is dialed in to desired TIR (offset or centered) in four-jaw chuck.  (Shop-built carriage stop/indicator holder is below.)
 
   
 
Yet another mill vise stop - can be rotated and/or moved sideways without changing the relative position of the stop.  Stop rod obviously can be moved in/out.  Can be rotated out of the way and returned to position and maintain relative position.  Vise is slightly modified for the stop as shown below.
 
   
 
After indicating the vise parallel with mill travel, the front jaw is removed and a skim cut taken at the vise stop mounting surface so that the stop will always be perpendicular to the vise jaw, no matter to what position it has been adjusted.  (A ground washer adds enough spacing to clear the front vise jaw.)
 
   

There is a spot of spilled paint on the side - no idea where it came from 

[Jim1611]

Not sure what I'd call this but it has been handy. 3/4 thick 6061 12 x 17.5 plate that can he clamped into my Kurt vise for holding flat parts that don't require allot of rigidity.



Here I used it to machine all 4 edges of a 16.65 x 20.65 aluminum plate. I did not move it until the edges were all finished so that assures that it is square. Just moved the ram to allow reaching the front and back edges.

[Dr Stan]

General purpose tooling/fixture plate.  The name will vary according where you are.

BTW, nice job.  

[randyc]

A 6 inch long boring bar mounted in a QC tool holder.  The 3/4 diameter
steel boring bar accepts 1/2 shank C2/C6 brazed carbide boring tools or
1/4 square HSS tools in a 1/2 diameter adapter as shown.  The cutters are
secured by set screws.
   

The same boring bar in a shop-made holder that replaces the regular lathe
toolpost, using the same mounting stud.  This is a very rigid setup.
   
 
Tool holder and tools for the regular four way lathe tool post.
The cutting tools are ½ shank C2/C6 brazed carbide or ½ shank
home-made insert holder.  All tools with ½ shank fit in the ¾
boring bar above.  (Note that the aluminum tool holder was to be
temporary, made thirty years ago - somehow I keep finding uses for it.)
   

[Jim1611]

(08-17-2017, 06:35 PM)Dr Stan Wrote: General purpose tooling/fixture plate.  The name will vary according where you are.

BTW, nice job.  

Thanks! Used it last night to cut the holes in my Jeep dash for the clock and tach.

[randyc]

OK, this is probably one of the first projects for an apprentice and there are many variations, so here's mine.

I’ve not used carriage stops often, probably because I rarely make more than a couple of similar parts at any one time. Mainly I use a travel indicator when it’s necessary to adjust lathe carriage travel distances more precisely than a 6 inch scale. Withdrawing a single-point threading tool at a consistent runout location is one example.

I have an inexpensive H-F magnetic travel indicator holder for my small Emco lathe and it works OK for that machine.

   

But the larger (Sheldon) lathe configuration can’t accommodate it so I had to make a holder. I wanted the holder to function both as a travel stop and to clamp an indicator, as in this configuration:

   

Note that there is a stop screw at the top of the holder, with a threaded locking wheel. This is to prevent running the carriage past the indicator limit and ruining it. Although the photo shows a one inch indicator in the holder, a two inch indicator is usually installed.

Configured as a carriage stop:

   

The limit screw was threaded to 1/4-20 so that every revolution equals .050 inch. It is fairly easy to adjust within .010 by eyeballing the knob. More exacting measurement is needed when precision is required, of course.

Disassembled:

   

All parts are steel and just for looks, I used my hillbilly coloring process on the two main pieces. This consists of torch heating the parts to a dull red and tossing them into a can of used motor oil.

This leaves a black surface that is slightly harder than the bare metal – it’s close to a black oxide finish. Other than that, I didn’t spend much time making the thing look nicer.

[randyc]

WARNING:  This is a L-O-N-G post for a S-I-M-P-L-E tool !!!

For years, I used an old technique for chasing threads on an engine lathe. The method consists of running up the tailstock near the work to be threaded (with any tailstock tooling removed, of course). 

A standard die in a die-stock was then positioned so that the back of the die was seated squarely against the tailstock ram and the die-stock handle was supported by the lathe carriage to prevent rotation.

   

There were a couple of problems associated with the method. The obvious one is that the chasing die cannot thread short workpieces. This is because the carriage blocks the tailstock from nearing the chuck/collet at the headstock of the lathe, even when the tailstock ram is fully extended as in this photo.

   

Although on small lathes, it is possible to disassemble the tailstock and reassemble it in front of the carriage, avoiding the above problem, it’s not something than many would like to do on a regular basis.

A second disadvantage that exists, no matter where the tailstock is positioned, is that the tailstock taper ends up containing most of the chips from the chasing operation.  The incredibly loud whistle when blowing out the taper bore with compressed air gets everyone's attention !

Surely tens of thousands of variations on the following tool have been made, this is just the simplest way that I envisioned it. The die-holding tool shown below passes over the lathe carriage with adequate length to work all the way up to the headstock.

Short pieces of 1 inch and 2 inch rod salvaged from under the bandsaw, were welded to the ends of a length of 3/4 pipe (1.05 OD).

   

I performed a primitive stress relief in the kitchen oven after welding and before finish machining the tool (incidentally, all lathe work except the front bore was done between centers). Three cycles from room temperature to 400 degrees F, allowing time to stabilize at temperature and time to cool took the better part of a day.

One end of the composite assembly was turned to a MT-2 taper which suits the tailstocks on most small lathes. The other end was bored to accommodate inexpensive hex dies, available from any hardware store, as well as standard one inch diameter adjustable dies.

Incidentally, to date, I have never needed to chase threads larger than 5/8 inch (after which, my blistered left hand was sore for days) single-pointing would always be my choice for threads greater than 3/8 or ½ inch. This is not from lack of sturdiness, the Emco is stouter than the majority of 12 inch lathes, but the drive train leaves much to be desired – no back gears and the belts slip under high torque !

In fact, the limitations of the 8 x 18 lathe shown in the photos suggests that threading any diameter over about 3/8 or so should be done on a larger lathe, although before I obtained my Sheldon, everything had to be done on the little guy.

The headstock end of the die-holder was bored in the same set-up that the taper was turned so that the dies would be well-aligned with the lathe spindle (if the tailstock is properly aligned). The three adjustment screws that serve to prevent dies from spinning also allow slight centering adjustment to accommodate any dimensional variation.  I am long remiss in replacing the socket head cap screws with some large head diameter, home-made knurled screws.

Opposing slots are milled through the pipe just behind the die head for clearing chips.  They are visible in the above photo.

   

A crossbar near the tailstock end prevents the tool from spinning and damaging the tailstock taper. When the die-holding tool is inserted in the tailstock, the bar is oriented downward, between the ways. In either direction the lathe rotates, the bar is confined between the ways, preventing rotation of the die-holder.

As noted previously, adjustment screws were included for centering the hex dies but I mostly prefer to leave them loose for small size threads. This allows a little radial movement (like a floating reamer). But the die is still held perpendicular to the axis of the workpiece.

   

   

This is a simple tool for a simple task; I usually thread at 120 RPM for dies of 3/8 and under, using sulphur-based pipe threading oil and pushing the tailstock by hand, which is not a problem on small lathes like this one.  Normally this would be a smooth trouble-free operation.

BUT this particular small lathe is single-phase powered so there is no instant reversing. As I near the end of the threads, I power down, let the spindle coast to a stop and then complete the few remaining threads by hand-rotating a large pulley attached directly to the spindle, first removing the belt for safety and to reduce the amount of torque required to rotate the spindle.  This leads to the following ...

OK, prepare for diversions from the topic -

After the painful experience of chasing a dozen 5/8-11 studs (I didn't have a larger lathe at the time, nor the correct change gears to single-point 11 pitch) I had to come up with a better way - even if it took longer.  There was no convenient way to turn the spindle manually by gripping some exterior feature. The large spindle pulley could be modified to accommodate some form of spanner but I didn’t care for that idea.

   

Since the gripping option (at least to my limited reasoning) was to use the spindle bore, this is what I came up with.  Clearly this would be an impediment if one wanted to run long lengths of stock through the spindle.  Fortunately that is a requirement that I've never encountered.

The internal expanding wrench is made from one inch O-1, torch heat-treated.  Parts of the tool display the original finish from the torch treatment.  The smaller parts are also heat-treated drill rod.

   

I have modified the “Compact Eight” by removing the large steel end cover, and replacing it with plexiglass shields at the front and top.  This can be seen in a photo below.

Previously, checking the belt configuration to know the spindle RPM, required opening the unreasonably big end cover. That was inconvenient because a large compressor is located near the end of the lathe; the end cover could be only partially opened. Changing belts was also a PITA for that reason.

In the current configuration I can easily see what pulleys are engaged and therefore know the spindle speed. The top panel can be pivoted backward to provide access to the spindle pulley. The rear area of the lathe is left open for lubrication, fast belt changes and for application of the spindle wrench.  (The length of the spindle wrench was established so that it cleared the plexiglass covers.)

When using the spindle wrench shown, I slip off one of the belts for safety, as mentioned previously, and to lessen rotational resistance. If the lathe somehow was powered up in reverse while the ½ inch drive socket wrench was set for forward rotation ….. well need I say more ?

(If the lathe was powered up in the same rotation as the socket wrench was set, the wrench would just rachet.)

   

The spindle wrench slips easily into the lathe spindle hole but attempting to rotate the wrench in either direction locks it to the spindle so that a socket wrench with 7/8 socket can rotate the spindle as required.

Getting back to the chasing tool:

When retracting the die, if the retaining screws have been left slightly loose (as I prefer), withdrawing the tailstock will leave the die on the work, to be unthreaded by hand and this may be desirable.  It's very simple to grasp the die and power up the lathe in reverse, die ends up in your hands in a second or two.  If any resistance is encountered by the die, well my fingers are a pretty good clutch.

If it's desirable to retain the die in the holder, a finger lightly placed over the front of the die will prevent it from slipping out of the holder. The lathe can then be run in reverse and the tailstock pulled by hand to unthread the die and die holder from the work.  I don't see any particular advantage in doing it this way.

I would note that it’s much easier to chase with a die by first turning the OD to a smaller and more convenient diameter than the nominal diameter. There’s no need to expend the horsepower and the wear on dies by forcing them to cut off more material than is required to meet unified thread standards.

My personal rule of thumb is to turn the major diameter about 3% below the nominal diameter. In other words, multiply the nominal diameter by 0.97 to obtain the diameter to which the rod must first be turned.

For example using this simple practice, 1/2 - 20 UNF threads suggests that the nominal diameter be turned to .50 x .97 = .485 diameter before chasing the threads. For critical applications one should examine the unified standards for proper dimensions (refer to “Machinery’s Handbook”).
I made this die-holding tool about ten years ago and each time that I use it, I wonder why it took so long to think of it 

[f350ca]

Nice design on the expanding wrench Randy. Will have to keep that idea.