15 Jan. 2010|
Small rotary table plans free,pvc furniture plans pdf,cat litter furniture modern - PDF Review
The more usual form of rotary table comprises a round table rotated manually via a worm and wormwheel. The inclusion of a stop mechanism will enable, when set, for the table to be repeatedly stopped at the same position.
It is likely that you may need to make some thinner table clamps so that the stop assembly seen in photograph 2 can pass over them, the alternative would be to make a larger base, say 150mm x 125mm. With the surface faced, return the tool to the centre of the table and advance it a further 0.05mm and face the surface once more but this time stopping about 20mm from the outer diameter. From this point, to achieve concentricity between bores, the table must not be removed from the faceplate until all the main turning operations have been completed.
Turn the outer diameter to a close but free fit in the table bore, and then make the 12mm bore, again this diameter is not critical as the mating parts will be made to fit. If you are uncertain regarding making and using such a small boring tool look here and here.
If you are using a fixed steady to support the material as suggested above, then this would be a good time to make the rotary table positioning bush 7 whilst still set up and using the same size material. Place the part in the three jaw holding it on the 10mm diameter and face the available end. With the release paper still on the strip wrap the strip tightly around the table and cut through both where they overlap. With that done, and using a draughtsman’s square placed against it, set the angle of the rule to the strip of paper so that the square when at 360mm also lines up with the other end of the strip of paper. Of course there will be some minor errors along the length but with the spacing being 15 +mm any errors will be proportionally small and the result more than adequate for its purpose here. Put the table onto the spindle and place a length of M8 studding fully into the tapped hole in the temporary spindle. However, before drilling can commence it is essential that one of the holes about to be drilled is in line with one of the M8 holes that have been used previously to secure the table to the faceplate. Whilst still at the first hole it is essential to add some form of fiducial line so that it lines up with one of the division marks on the table.
With all 24 holes now drilled the paper strip can be removed as the tables own inbuilt divisions can be used for positioning the handle holes and the tee slots. Making the handle holes now, with the assembly still in the vice, rotate the table such that the axis between the two M8 holes is horizontal and engage the detent, also re-clamping the table. Set the rotary table with the 2 M8 holes in line with milling machine axis and engage the detent. With the first groove complete release the table, remove the detent, move the table through four holes, refit the detent and secure the table once more and machine the second groove. However, it would be a good idea first to move the table through four holes, mark the table, move through a further four holes, mark the table and repeating for all six slots.
Replace the end mill with a tee slot cutter and finally machine each slot, still using the same table stop position to set their lengths. Whilst in milling mood set the table upright on an angle plate and machine the 12mm entry into the vee slot for fitting the vee nuts. With the table removed from the milling machine, place the component carrier in the table bore and secure with an M6 screw, washers and nut through both carrier and table, then transfer the tapping size holes to the table. Place the base onto the lathe’s faceplate and centralise it using the tailstock centre in the 8mm hole and secure in place with screws through the two 9mm holes. Place the assembly onto the lathe’s faceplate, centralising it using the tailstock centre and secure using fixings into the two tapped holes in the table. We now have a chance to put the table to use and almost certainly with one of the most demanding tasks you are likely to use it for, but first of course, it has be be assembled.
Fix a toolmakers clamp to the left hand side of the locating plate such that when the material for the part being made is placed against it the right hand side is level with the right hand side of the locating plate.
Now place the material for the workpiece against the toolmaker’s clamp and position it such that the end just overlaps the edge of the table by about 3mm and secure using two toolmakers clamps, again do ensure that they are correctly closed. If you do not have sufficient clamps the first could be replaced with a fence, secured using tapped holes in the locating plate and screws through clearance holes in the fence. With the radius fully across the width, and a little less than tables radius, the curve can be completed by stepping the cutter down by 0.5mm at each pass (Photo 22). If you have a tilting vice, or angle plate, then this is obviously the method to use, machining sufficient for two and splitting them afterwards.
With the table now finished it seemed appropriate to make a link with radiused ends, being typical of the tasks it is likely to be called upon to perform.
In conclusion, I was very pleased with the end result with it performing better than I could have hoped and can see me using it in preference to my more usual tables for many applications. However, placing something as heavy as this, even approximately, can be a problem and using faceplate dogs as seen in Photo 4 would make the requirement very much easier to achieve. This ensures that in the final assembly that the table will only contact the base around the outer edge helping it to sit more accurately. This time, pack the table from the faceplate using a piece of hard card, also setting the material to run sufficiently true to permit it to be machined to the 120mm diameter. To set the 120° divisions, place a suitable length screw into a tee nut and these between one of the chucks jaws and the lathe bed. Turn the outer diameter to achieve a close sliding fit in the bore in the table, then, using a largish centre drill produce a centre of about 8mm diameter. Its purpose being to enable a screw to be fitted which can then be used to lift the bush out after the table has been positioned. You will now have a strip equal in length to the circumference of the table which will require dividing into 24 equal divisions.
Using a length of 12mm diameter steel, place this in the three jaw and turn the outer diameter to a close fit in the table bore and over a length of 18mm.
This ensuring that there is at least 10mm of free thread to be accessed from the other end. At this stage the table can still be rotated but to prevent this place a plate over the M8 stud and with a nut tightened onto this making the table captive.
The easy way of achieving this is to loosen the table and rotate it until one of the holes is at the top, as is also the stop post. The photograph shows that I used a piece of adhesive paper, suitably marked, on the base and against the table.
Move the assembly so that you are now in a position to drill the hole for the handle and once more secure the assembly to the drilling machine table.
Next, transfer the assembly to the milling machine table setting one of the edges of the base at right angles to the tables movement, secure the base but still leaving the table free to rotate.
Do not though rely on the detent to secure the table but add an overhead clamp as was shown in photograph 16. Take the plugs and distort the first two threads at the slotted end using a centre punch into the thread’s groove, doing it at a couple of places around the circumference.
Remove, tap the table M3 and drill and counterbore the carrier, return the carrier to the table securing it with cap head screws. Then, lightly resurface both the table and carrier so that the carrier surface is level with the table, remove and dismantle. Using the three jaw fitted with its reverse jaws would give a step onto which in can be placed, alternatively using soft jaws suitable machined.
As the depth of the tapped hole is now restricted by the plug that has been added, use a stud with nut and washer rather than a screw which may contact the plug before the table is fully secure. This is straight forward but if you think the table can lift too much then the table spindle can be reduced in height a very little. Not having used a rotary table in this way before I have to confess I started the machining with a degree of apprehension. DO take note that it is vitally important that the direction of rotation of the table is opposing that of the cutter. About 10mm in from the tables edge on the underside, drill four holes 6mm diameter and 6mm deep, approximately equally spaced on a PCD.
To overcome this, I have included two features that are not to be found on a conventional table, at least in the smaller sizes. The one making the table may though like to standardise on some other size which is being used in the workshop, in this case, the 30mm height may need changing. First drill and tap M4 hole, followed by turning the 10mm diameter, which should be a close running fit in the table, even slightly stiff would not be a problem. All these require the table to be divided into angles of rotation, being, 3, 6 and 24 divisions. With the rotary table positioning bush in the table, centralise the table below the machine spindle using a centre in the machine spindle as shown in Photo 16 and lock both the X and Y axis table movements.
Now, free the X axis (left-right) and using a 10mm slot drill, machine the centre section of the first tee slot.
Do make the 10mm bore a close fit on the table spindle else the table locking screw will be able to move the table sideways. Place this, then the table, over the spindle and the tables positioning bush in the tables bore.
Otherwise, there is little that may need attention other than to add a little lubrication in the obvious places. At this stage the curve should be just inside the tables periphery such that it has a very marginally smaller radius than the table itself.
For me this was a stern test for the table which it completed with flying colours proving therefore that it will quite easily cope with the simpler tasks that it will most often be called upon to undertake. Also, if you’re rotary table requires larger tee slots, having only four rather than six slots might be appropriate.
However, I have used the 24 holes to position the tee slots and the holes for the handles, but if omitted, the method used for positioning the 24 holes could be adopted for placing the tee slots and handle holes.
This ensures than when placed against the table it contacts it at the edges of the part rather than centrally when it may rock. Do ensure that the plug is very firm in its thread and that only a small amount has to be removed, say 0.2mm. Set the table stop to fix its length, thereby ensuring that all six grooves can easily be made without the need for further measuring.
Take it steady machining it as the rotation of the cutter will be attempting to unscrew the plug.
The purpose of the plug is to stop swarf entering the hole which would be difficult to remove and could effect the rotation of the table when in use.