Page BottomThis lathe is the first one i started, in the cellar, on a 12ft x 4ft concrete pad i poured for it. Problem was the neighbor's rottwilers. They didn't want me in my cellar, they didn't want the cellar door open, and the local district attorney's office sided with the dogs, because i have trouble walking. It's my house, it's my land, there's no mortgage, no loans, no taxes due, nothing, it's all clearly titled in my name. The dogs control it. At least from ~2001 till perhaps 2009, we'll see.
So it's now 2010, the dogs have been off my property for a year now. I still plan on moving away, and don't see a 10ft lathe in the cellar, down the mountain, as moveable, or boat-able. So i cut it in half. I figure i can always put a bed extension on it later. The steel i am using for the rails now was to be the top and bottom of a box beam construction, the heavier 10" wide rails are now a car ramp.
Here lengthwise, shown with cat and chair for scale. The rails are 12.5 inches apart, inside measurement. It's flat from head to tail within a paint layer. The "anti-twist" tubing (not pipe) down the ~center is 1/4 wall 6.5 inch OD steel, the side rails are 8 inch channel, the two head bearing plates are 2 inches thick (so are the bearings) for 7 inch OD bearings.
The two head plates are 4 inches apart (inside measurement). It's currently sitting on scraps just to keep it off the ground. I have two 3inch plates to sit on the channel rails for the carriage to roll over, if you click on the image to open a new tab and bigger view, you can see the tops of those 50 year old channels look like some beast has clawed the devil out of them.
Preparing to weld 3/16 plate in as oil and swarf catcher. The plate is a friction fit, with one edge ground straight, and a few holes where it sits on the anti-twist tube. It's a friction fit, i used the car jack leaning against it to spread the channel a shade till i got it in place. The short 3" channel clamped across the top has measured spacers to hold the plate identically from the top of the side rails and level front to back.
There it is, welded all the way around, on top. I'll flip it over and do some work on it's undersides when it cools, tomorrow. And clean it up tomorrow. It's considerably stiffer now. Note the top of the front flange looks a lil wider? That's the 3 inch wide plate i laid up there for the moment. There will be a piece on the back rail too, to hang over the inside and give me a flange there to hold the carriage down.
Setup for making a couple spring-loaded arms. Those are bearings under the arms on the 1/4" split roll pins. This setup lets me weld the two arms at the same time, and know the rod is oriented squarely on both of them.
Here they are, cut apart, and set like they will work. That's the underside of the carriage. The bearings on the front are fixed in place, these will push the carriage against the front bearings and keep them firmly on the front rail. While i don't really care too much about the placement of the rear rail, if these move more than .02", something is dreadfully wrong.
The underside of the carriage.
The big H thing holds the bearings that ride under the rail top flanges, and hold the carriage down against vibration. The bolts in the center of the H don't do a lot, but they are snug in all dimensions, and i needed them during assembly, so i left them there. The bolts at the ends of the H near the bearings have springs under them, which i'll nearly collapse so there's very little play in the up direction. Ideally, there should be zero play, but real life can be complicated.
Those 3 inch long springs push the arms with bearings, to keep the carriage up against the front rail. Those two stationary bearings on the left are what guide the carriage there.
Front edge stationary bearing and the holddown bearing. All the bolts with bearings on them are grade 8, so they won't bend. There's a lot of rust, i'll get rid of that later. As you see thruout the carriage, all nuts are nylocks.
Rear hold down and the spring assembly (not yet tightened). That's a tough little spring out of a large truck torque convertor. I can crank each of these to 100lbs easily, but i don't think that much is needed. The bearings are good for a few hundred pounds.
Here's a great use for a overhead bridge crane in a shop: moving the braced and clamped rails for the big lathe. Most of that mass is for alignment and fixing in place the two 2x0.5 slivers of plate that table will slide/roll on. That's prolly a couple hundred pounds weight hanging there. I luuv my overhead traveling bridge crane!
And here's the contraption on the lathe body itself. I then put a few bolts in for alignment and snugged them down very lightly. This better be adequate alignment for a coarse brute force lathe built in a driveway. Tomorrow i can drill out the pin holes (they are full of goo right now) and drive in the roll pins. And the same for the rest of the bolt holes, and use nylock nuts on the bolts. And then make a mess of everything by using a "body grinder" to wirebrush excess bondo.
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Here's a mirror shot up under one end of the table. That whole assembly is old, it spent all winter outside. There's spring loading against the front rail (four bearings between the rails), and a hold-down bearing at each corner.
A view of the lathe so far. Not even got the head ground for the bearings yet, and it's covered in swarf. The grinder with the disk on it is in the pipe to be used to grind the bearing holes in line with the rails.
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A 4inch diameter heavy wall tube, held up on bearings, bolted to the bare table. The top and back bearings are adjustable to take out all play in the tube.
See how it is aimed at the lathe head plates. Those are torched undersized, and this jig will bore the spindle bearing seats aligned perfectly to the ways.
Grinder carrier mounted to tube.
Inserted into first 2" thick plate.
Turning the tube to swing the grinder around in the hole.
Moved to the back plate.
The distance from the A-frame holding the tube to the end of the grinder is so long because i didn't want to remount anything to reach the back of the back plate.
Some results of grinding. The front plate went from a very rough plasma-cut 6.75 diameter hole to a pretty good 7 inch hole. The bearing OD is 180.1mm, a lil over 7inches.
Click here for a 4 megabyte short avi of the grinding operation.
Note: i was turning it with one paw while holding the camera with the other paw, so it's shakey.
It's now as aligned to the tailstock as it can be.
insert spindle between head and tailstock.
On it's temporary wheels, moving into the house. This was originally supposed to be a lot longer, and in the cellar. Instead, i built it in the driveway, 1/2 length, and it lives in the livingroom.
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