NOTES FROM WORKING ON A WIEDEMANN R-2 TURRET PUNCH by Grant Erwin July 2017 In June/July 2017 I rebuilt one of these machines. At that time I could find no information on how to take the machine apart or reassemble it, so I had to use the "white cane" approach and figure it all out myself. I wrote this document for future reference. When it wasn't clear what to call a part I gave it a name which may or may not make sense, so I have included a nomenclature section at the end of this document. This is not an owner's manual per se but I do touch on lubrication inasmuch as it is possible to swap two nearly identical parts by mistake which would render some part of the machine unoilable. Assembly notes: If the lockout bar is installed before the upper platen, it will be very difficult to get in and screw in the upper platen retaining bolt and washer. If the indexing pin spring adjusting nuts are the same depth, then the lower pin will lag behind the upper when the indexing handle is rotated to allow the platens to turn. The indexing handle's eccentric starts out closer to the upper indexing pin, thus it wants to pull it out first. If the upper spring exerts more force than the lower, this should counteract this tendency and both pins should retract the same. Index pin installation: This goes easier if one of the small cotters in the transverse retaining pin is left installed. Start by carefully deburring the indexing pin's slot and retaining pin, until you can smoothly slide the pin through the hole in the indexing pin. You may need to deburr the retaining pin as well. If the index pin bar is out, stone off any burrs on it which would impede the bar sliding into the slot in the end of the indexing pin. Before the indexing pins are installed, it is possible to adjust the upper or lower spring retainer. Adjust these prior to installing the indexing pin assembly. If they are too loose the indexing action becomes erratic. If they are too tight it will be difficult to install the index pins. Tighten the upper spring as much as you can get away with. Tighten the lower spring quite a bit less. This should help with retracting the pins. Start by pushing the indexing pin into the hole, compressing the spring until the pin's shaft extends out far enough to slide the bar in. Before touching the bar, slide the retaining pin into the hole in the indexing pin far enough so the retaining pin will stay in place but not far enough to block the slot in the indexing pin. Now slide the bar into the notch while holding the indexing pin against the spring pressure and while you maintain light pressure on the retaining pin until the retaining pin slips through. Align the hole in the retaining pin so the hole's axis is vertical and drop in two cotter pins. Do not bend the cotter pins yet. Use the same procedure to install both indexing pins onto the bar. Then slide the indexing (platen locking) handle into the main casting of the machine, making sure its eccentric pin engages the slot in the indexing bar. Now test the action of the handle i.e. make sure both pins retract correctly. Slip a no. 10 washer over the eccentric pin and install a cotter pin. Bend the cotter pins on the indexing pin retaining pins. If the platen indexing pins bind during retraction, check these: the indexing pin's hole needs cleaning and/or lubrication the platen pinches on the indexing pin because its bolt is loose the eccentric pin on the punch handle shaft is bent Barrel bushing installation It is convenient to use a speed wrench to quickly thread in the rear set screws. While it is tempting to install the front set screws the same way, i.e. from the rear using the speed wrench and a T-handled hex wrench, that would make adjusting the chain tension difficult. So install the rear set screw from the rear and the front set screw from the front. The upper barrel bushing is installed with the machined flat side down and the beveled side up for oiling. The lower barrel goes in the other way, machined side up. Sprocket installation (rear sprockets, not the front ones on the platens) The two sprockets are not identical. The lower has has a cone-shaped oil hole near the bore. Fit the upper sprocket to the shaft, lightly pressing in the tapered pin. The boss on the sprocket must bear against the barrel bushing. Don't tighten the set screw at this point. Slip the sprocket shaft up into the upper barrel and lightly clamp the sprocket to the frame so the shaft doesn't drop. Slide the lower sprocket on, conical hole side up. Hold the sprocket up with one hand during installation of the lower barrel. Next, slip the lower barrel up from below and tighten the rear set screw to hold it in place. Then allow the sprocket to slide down the shaft into the right location. Line up the holes and install the taper pin lightly. If the taper pin won't go in, it is probably because one of the barrels is installed upside down. Thread the 4 jam nuts onto the outer ends of the set screws and tighten against the frame member light finger tight. After the chains are installed and tensioned, drive in the taper pins and tighten the sprocket set screws and their jam nuts. Platen installation Before installing or removing the upper platen, remove lockout bar and the punch handle assembly and its cover to access the retaining bolt from above. The lower platen has to be mounted first when assembling and last when disassembling. Remove all the die holders from the lower platen. Look carefully at the machined boss on the machine where the lower platen rotates. Clean it. Stone away any burrs. Grease the machined flat. Lightly grease the hole for ease of assembly - the platen axle is lubricated by a central oil hole on top. Lower the platen into the hole. Reach under the machine from the back and thread in the retaining bolt and thick washer. Note that this retaining bolt has no oil hole. Once the lower platen is in, place the upper platen (all punch holders removed) onto the lower platen. There is just enough clearance to allow the axle to fit under its boss. Look down from above to align the bolt and the hole. Rig both sides of the platen to an overhead lift point and lift the platen until it is off the lower platen but the axle has not yet engaged its hole. Thread some 1/2" allthread into the axle from above and lift the allthread with one hand while you slightly move the platen with the other until the axle starts into its hole. Raise the platen with the overhead lift, then pull the axle all the way up with the allthread. Remove the allthread and install the washer and 1" long retaining bolt with oil hole. Platen removal Remove both roller chains. Remove all punch holders, vee pins, springs and set screws from the upper platen. Remove all die holders and screws from the lower platen. Put a pair of rods into opposing vee pin holes (3 and 9 o'clock). Slip a sling over the protruding rod ends. Use an overhead hook to lower the platen. Once the upper platen is sitting on the lower, push the axle down until its top is free. Remove the platen and axle from the machine. Remove the bolt and washer from the lower platen. With the retaining bolt removed, lift out the lower platen. Die holder installation/removal When removing the die holders, notice the screws are different lengths for each size of die holder. Make sure they get reinstalled with the right length screws. Remove the chains. Remove at least one punch holder. Retract the indexing handle. Now the platens can move independently. Rotate the upper platen so the empty hole is out to the side. Now reach down through the hole with a hex wrench to access the socket head cap screws that hold down the die holders. On assembly, install the die holders first, then the chains. Punch holder removal Move the holder into position to punch a part. Check that the vertical set screw on top of the upper platen behind the punch holder is loose. Move the machine handle until you can access the small transverse hole. Push a tool through the hole until it bears on the vee pin. Push against the spring pressure to retract the vee pin. Holding pressure, turn the punch holder a little so that it is free from the vee pin. Remove your tool and pull the punch holder out the top. The vee pin will pop out, so be ready to catch it. Installation is the reverse of above. There are a couple of nuances about the vee pins and springs. All 12 vee pins are identical, but six of the springs are about 0.150" longer than the other six. The vee pin holes adjacent to the platen holes for the larger size punch holders are correspondingly deeper. So the longer six springs go into the deeper holes, which are next to the larger punch holder holes. Punch installation Some punches have one locking flat; some have two. Some punch holders have one set screw; some have two. Sort things out carefully before you start installing. If the punch does not slip into the holder, don't force it - stone off the burrs on the ID of the holder and (if necessary) the OD of the punch. It takes some work to clean everything up but it's worth it. If the set screw doesn't thread right in, chase the threads with a tap. Use shims to effect vertical adjustment on the punches. Measure all of the punches in their holders without shims, from the flat end to the tip of the center point. For each of the 11 holders that are shorter than the longest, calculate the needed shim thickness. Then fabricate the shims and install the shims and punches into the punch holders. After you install the punch clamping set screws, you must ensure that no part protrudes out of the holes they are threaded into. If they do, you can sand them shorter. A convenient way to hold a short set screw for belt sanding is to hold it on the end of a long hex wrench. At the same time as you are checking the set screw holes in the punch holders, check the outside of the holes for burrs. Remove any burrs by stoning or sanding. Punch holder installation All punches should be installed in their punch holders before the holders are installed in the upper platen. Rotate the platen so the target hole is out to the side for easy access. Apply lubricant to the outside of the holder. I used anti-sieze. Check that the vee pin is vertical. Use a tool to push the vee pin out of the hole and hold it there while you tighten the set screw to hold it. Slide the punch holder down into the hole, with its vee slot pointing in. Loosen the set screw so the vee pin snaps into place. Check by trying to rotate the pin. Adjust the punch holder height so it can slide into the slot in the ram. Punch/Die alignment After the punches and dies are installed, each pair must be carefully aligned. To align a particular pair, turn the platens until the desired punch holder engages the ram, then lock the platens by releasing the index pins. Check that the socket head cap screws that hold down the die holder are loose enough so you can move the die holder around. Lower the punch and move the die holder until the punch enters the die. Lower the punch handle fully and move the die holder with one hand to center it, then use the other hand to tighten the screws. Check afterwards that the punch does not touch the die anywhere as it is lowered into the die. Repeat the alignment for each of the 12 punch/die pairs. Chain installation Do not install the chains until the die holders are installed. Retract the index pins. Use a piece of wire with its end bent into a small hook to thread the lower chain in front of the platen sprocket. Then use the wire to fish both chain ends through the punch body and out the back. Put the chain on the front sprocket and then onto the rear sprocket. If it is tight, adjust the tension looser. Move the chain and platen until the gap between the chain ends is closest to the back. Insert the master link from below. Put the other piece of the master link over the master link pins and then install the spring clip. Next rotate the upper platen until its zero mark is directly above the zero mark on the lower platen. Release the index pins. Move both platens one way or the other until they lock solidly. Now they are correctly aligned with each other. Install the other roller chain the same way as you did the first, this time taking care that the platens move together. With both roller chains installed, tension the chains using the adjusters in the barrel nuts. Tension each chain until rotating the platens starts to bind, then back it off a little. Don't worry about the platens moving with respect to each other because the indexing pins will ensure they are accurately aligned. NOMENCLATURE Lockout bar This bar is viewed by looking down on top of the machine. When you turn the platen release handle to release the platens to move, the lockout bar engages the teeth in the punch handle shaft so that it is not possible to move the punch lever. Punch handle The 3/4" bar that the operator pulls on to punch a workpiece. Index pins The spring-loaded pins that engage the holes in the edge of both platens ensuring the platens are correctly aligned and preventing them from rotating. The front end of each index pin is machined to a bevel which matches that on the platens. The back of each index pin has a notch in it. The index pins are machined with a shoulder for a spring to bear on. Indexing handle The handle the operator turns to release the platen indexing pins, allowing the platens to rotate. Index pin spring retainers Each index pin's spring is prevented from coming out the back of the machine by a threaded bushing which is slotted as if for a large straight screwdriver blade. I call these spring retainers. Index pin retaining pin A small pin a bit longer than the indexing pin is wide. As mentioned above, the back end of each index pin has a notch machined in it. The part of the index pin on each side of that notch form 'ears'. These are drilled with a transverse hole the size of the retaining pin, so that the retaining pin can go through both ears. This is how the indexing bar is connected to each indexing pin. Indexing bar A piece of flat bar steel with a central slot and a hole at each end. Each end of the indexing bar is pinned to an indexing pin. The eccentric pin in the indexing handle's shaft rides in the slot. Rotating the indexing handle clockwise moves the indexing bar towards the rear of the machine, pulling the index pins out of their holes in the platens. Chains A pair of identical lengths of roller chain. Each is fastened around one of the platens and around a sprocket on the vertical sprocket axle. Sprocket axle A vertical round bar with a sprocket pinned to each end with taper pins. The sprocket bar rotates in the vertical holes in the barrel nuts. Barrel nuts Two barrel-shaped bushings which hold the sprocket bar in place but allow it to rotate. The barrel nuts have indents on their sides which engage long set screws. The chains can be tightened or loosened with these set screws. Ram The ram engages the punch holder and moves up and down as the machine handle is moved through its range.