WORKSHOP TABLES can be found HERE
| Providing Tables and Data. Still plenty to do, but it probably could end up being as big as the proverbial Engineers manual.........like heck!......my web page service provider wouldn't give me the space I'm sure, and I haven't got that much time! ..... so it will be selected bits |
Workshop Tips can be found HERE
Intended to provide some useful ideas .......
| Converting the Super X1 mill for CNC ....... a new project starting from scratch as a novice on the subject ....... follow the progress. |
| Band saw Vice ...... |
| Want a vice to go into the vice on a band saw so it will cut right up to small pieces......the test? It will cut a pound coin (that's UK currency) in half edge on..........the designer claims! See later down the page. |
| Tool Cutter/Grinder ..... Stent |
| Sooner or later that essential tool will be required ...... See later down the page |
| Four Facet drill sharpener ........ |
| Small drill sharpening a headache ?.......... make one of these ........ See later down the page |
| DRO ........ |
|
Radius turning tool......... J.A Radford's design ........ See later down the page ........... This tool is a must for turning any form of radius and of course balls. |
| DRO bits |
| As I have changed my mill/drill to a proper turret mill the DRO has changed. I still use the Ortec but the table travels are longer and new sensors had to be fitted. Ortec were willing to exchange these with the addition of a small sum for the extra long X table |
 |
This the X axis view. The DRO is an optical based system with the read head fixed and the sensor bar moving with the table. This keeps the cable in one place The sensor is stood away from the table to allow the electrical stops for the power feed to operate |
 |
The Y axis sensor bar is on a bracket off the underside of the X Table with the read head on a short bracket off the bracket forming the mechanical stops. Putting it below the X table allows the leadscrew bearing block ....that green blob in the top left of the picture......to clear the sensor and give full table travel. The whitish blob below the green blob is the X table power feed and gearbox which hangs below the table. |
DRO v Graduated Handle
|
I had an interesting e-mail from someone who had an interest in fitting a DRO and decided to check out their accuracy's at one of the exhibitions by winding the table over a few inches ..... and the full length.... and comparing the DRO with the table micrometer dial reading. Surprise, surprise....... there were inconsistencies. He claimed 0.002"per inch was noted over a few machines. That's up to 20 thou over full travel and maybe more on most model engineer sized machines. Now my DRO is an ORTEC with a resolution to 1 thou (three decimal places on the the display). ORTEC publish an error of 0.001/inch ( at least they specify it rather than saying nothing).... So I decided to check my mill/drill (as it was then) over the full movement. I had the same sort of cumulative error! Having two readings helps nowt as you can't fathom out which one is correct. So I placed a micrometer in the machine vice and moved the table against a DTI set up on a magnetic base to the vertical pillar. Sure enough the micrometer confirmed the DRO reading. So what's wrong? |
|
Now I put this down to inconsistency in the lead screw pitch. The popular Taiwanese sourced tools do not generally come with a certified accuracy as tested prior to dispatch and it is a probability that for the price we pay for such a machine we can expect such errors as the master machines may not be as high a standard as is necessary to achieve the accuracy and consistency in production to give better results. Who knows .... if its a metric master have the calculations to imperial been done with enough accuracy? Any other theories out there? However since replacing my mill/drill with a turret mill........also of Taiwanese origin .... my initial checks have only shown a 3 thou error over full X table travel of some 18" or so ........ not complaining about that.......... |
| Back to the top ...... |
| Building workshop equipment is part of every modellers life. One of the earlier projects was this Stent cutter/grinder. Its really an essential item...or something equivelent.....if you need to sharpen those mill cutters etc. | ||
|
Anyhow, here's a pic. of my version of the Stent. |
 |
| It was built from Blackgates drawings and castings. This one has a short horizontal base travel for the wheel post. Later castings have the option of a longer horizontal travel base and if it had been available when mine was built I would have chosen that version. | ||
| One modification I have introduced is the 180 degree table under the tool post holder. Having this graduated base makes set up that much easier. The motor is a 3000 rpm 1/8 hp.....just enough to drive the small wheels..largest 4" dia. without stalling on a cut . |
 |
How often do you need to put a radius on the end of a lever or link around a hole which usually takes a pin? ...... Well, I made this simple device to go on my Stent. It consists of a series of 1/8" holes around the periphery on an inward spiral so that each hole is further away from the edge than the last. 1/8" pins are a push fit into the holes and form the pivot around which the radius can be formed. Pins with larger or smaller diameters can be used depending on the required hole size in the lever or link. The reason the holes spiral away from the edge is so that the maximum amount of support is given under the lever or link being ground depending on the required radius |
 |
 |
|
| These two pictures show the set up used for regrinding saw blades. The knurled clamp screw allows the blade to be released and indexed around to the next cut set by the indexing finger. The index finger is rigidly clamped to the top of the 1 inch screwed mandrel over which the blades fit. The lower part of the mandrel is a smooth one inch diameter. The clamp having an internal relief of one inch diameter to be a close fit. The screwed part is 16 TPI to BSF form with the outer diameter 0.98" to allow the saw blades to easily slide over. The main body is two inch diameter with a slot cut half way through to accept the clamp screw. | ||
 |
Another addition is the three axis table shown here. This is a useful addon as square tooling and and other odd tools are more readily adaptable on such a table to present to the grinding wheel. The table has been made from odds and sods of materials as available in the scrap box. The table top is aluminum. The slide is cast iron. The axis on which the slide is mounted is mild steel. Another piece of aluminum forms the bottom axis which in turn is mounted on a mild steal base. The table is 100mm square to give some idea of scale
|
|
 |
A closer view of the 3 axis table with the slide rotated through 90 degrees for a better view. The slide only gives about 3/4" of movement which is plenty, the main alignment to the wheel being done with the main table. No slide is needed at 90 degrees to the existing slide as the wheel is moveable in this axis. In operation the table is rocked back and forth on the bottom axis with the tooling against the face of the wheel which ideally should be a cup wheel as grinding on the side of a disc wheel is not recommended. Another benefits is that the tool holder block seen on the adjacent post which is designed for round tooling will bolt onto the table. The brass packing and bolts can be seen hanging below the block. The brass packing is required to lift the block 40 thou. to give clearance to the knurled ring that tightens the tool holder in position. |
| Back to the top ...... |
|
I mentioned the new vice at the top of the page. Its for a band saw and allows cuts on very short metal pieces ........ which, as those of you with a band saw will know, can't be done without risky packing arrangements to get the vice jaws extended to nearer the blade. This vice clamps into the existing vice but its jaws span the blade ..... i.e. the blade cuts through the jaws of the vice. A nifty idea and the vice design is the subject of a granted patent to the designer. As the design is copyright protected I cannot publish it without consent. |
However, here are some pictures of the vice I have made. It is not 100% complete as it has to have what are termed 'flipper bars' fitted which are two bars rotating on a pin between the two lugs on the right hand side of the body. These bars flip over to sit on the vice base between the jaws and under the work to be cut The benefit of these is that small pieces which otherwise would fall in the gap can be supported.....However using scrap metal underneath is just as effective and practical as the saw blade cuts into this. Scrap metal can be discarded.......the flippers are an attachment and would have to be replaced as well........some time........its easier with scrap ......as long as its parallel bar round or flat. |
 |
The block on the left of the vice fits into the band saw vice jaws as can be seen in the lower two pictures The handle is on a dog so that it can be moved to clear the band saw base |
 |
 |
Here the vice is in the band saw with the blade posed between the jaws to illustrate the workings. The lug on the bottom of the vice base is matched by one on the other side so if required it can be removed from its mounting block and used as a normal bolt down vice (except mine are not drilled!) |
 |
There are a couple of points to note ....... firstly the vice is now higher than the normal band saw vice and the auto stop lever will not operate unless lengthened. Perhaps a right angled stop lever could be used with a leg long enough on each to suit whether the vice was in or out.
Secondly, to get the saw blade right down to the base the left hand roller guide needs to be adjusted right back to clear the vice body. (Its not shown like that in the picture)
And thirdly, the vice handle may catch the saw table if the vertical bit is too long (mine does!) Its not too bad as its on a dog but it would be better if full rotation could be achieved.
| Back to the top ...... |
A useful device for the workshop is the small drill sharpener. Even more useful is one that will put on our facets.
This particular design is by D.A.G.Brown although I have modified it a little to provide for a magnetic base onto which diamond plates will fit and can thus be moved about to avoid wear in one spot all the time due to the sharpening process. It also allows different grades of diamond plate to be used depending upon the amount of metal removal required. To break the magnetic circuit around the tool the slides are now made of brass rather than steel as in the photographs. This allows the tool holder to slide more easily due to it not being attracted so strongly to the base.
A second block was made for larger drills. The block is the same size but the collet holder is 3/8 square to allow drills up to 3/16 to be sharpened.
 |
 |
|
| Back to the top ...... |
Turning any sort of radius by hand is at best very skilled and at worst a disaster waiting to happen. There are a number of designs for turning radii and they fall into two basic camps.
Firstly there are those that cause a tool to swivel about a vertical axis i.e. the tool cutting edge is in the same plane as a normal lathe tool and it rotates about a vertical axis which is some way in front of the tool tip depending on the radius to be cut. The tool cutting forces tend to bend the tool down as in a conventional set up.
 |
This design is by Jay Tuckwood and may be found on the website; http//www.metalwebnews.com/howto/baltool
|
Secondly there are those which rotate about a horizontal axis i.e. the tool cutting edge is now set on a vertical centre line of the work rather than a horizontal one, usually at the top of the work. This arrangement causes a tool to rotate horizontally and the cutting edge of the tool tend to exert forces along the tool axis and is therefore that much stiffer.
Here is the one I chose and built:
| The design by J.A.Radford is of the horizontal axis type and the finished product is shown in the pictures here. |  |
|
 |
The complete tool from above and on its side. | |
 |
 |
|
| The head has two positions for the tool holder. As shown it cuts a normal radius or ball. With the tool holder in the other position it will cut concave radii. The tool holder is screwed into position. As the tool holder position is unique to its screw thread, each position has its own holder. |
The adjustment for the head is similar to most boring bar arrangements. There are 25 divisions at one thou per division. The lock screw tightens onto the slide via a piece of brass at the correct angle. |
|
| ........ and in use cutting a 3/8" dia half ball. The cutter is shown at its right hand end of travel. As it rotates to the left it rises to the top of the work. |  |
| Back to the top ...... |
That's all for this month ........ thanks
for calling ...... come back again.