shenion
Tool Pack Rat
- Messages
- 7,586
- Location
- Stone Mountain, GA USA
This was not supposed to be a welding job. Just a lathe project.
I am making an ER-40 Collet chuck for my lathe. Basically, it is a 2.25" 6063 aluminum bar bored and threaded to fit the lathe spindle. The opposite end has a taper to fit an ER-40 collet. Here's a pic:
As this is made on the lathe, it is real accurate. Will be nice as my 3-jaw chuck is sloppy.
I made a ring that attached with 3 screws to clamp the collet. It worked OK, but had some play. I decided to use a commercial ER-40 clamping nut. this has a 50mm x 1.5mm internal thread.
So grabbed my lathe manual, looked up a thread pitch of 1.5mm and started to cut the thread. I had checked the gears several times. The pitch was wrong. Turns out the entire table was wrong. The manual was written in 1937, so metric threads were few and far between
No now what?, I don't want to start over especially since I don't have any more stock.
I first tried TIG welding. That was a failure and all I have is 4043 wire. The 6063 takes a huge amount of heat. FInally get a small weld pool and the 4043 wire will melt long before you get near it.
So, plan B. Grabbed the MIG and some 5356 0.9mm wire. Some short tests worked, but longer welds ended up with a birdsnest. I had forgotten I had switched to a 0.9mm liner. I switched to the 1.2 liner and it worked well.
I set up the lathe as a weld positioner; heck the chuck was already mounted on it. This required making a plug to fit the far end of the spindle to allow the work lead to connect but still spin.
Set the lathe to about 6 RPM. Was hard to see and follow; maybe I should have clamped the torch in the carriage and set the gears to 4 TPI. Would have been full robotic weld.
Came out ok, had a few jitters and caused some small pits. Did have a 1/2 turn that I had moved too fast. So, cleaned up and touched it up manually. Since MIG starts cold, I would start on a high spot and then move to the low spots. That made it looked even lumpier.
Had just started cleaning it up and took a pic. I had a collet in the chuck to protect the taper and also prevent any chance of too much penetration.
Turned down to 50mm and the correct threads cut. I found a later manual. It had a different gear setup but was still wrong. Was easy to figure out though as it was off by a factor of 2.
All finished. Put in a test piece and could not measure any offset. The chuck will hold work from 3/16 to 1" (4-25mm).
The full details of how i mad ethe chuck are shown here.
I am making an ER-40 Collet chuck for my lathe. Basically, it is a 2.25" 6063 aluminum bar bored and threaded to fit the lathe spindle. The opposite end has a taper to fit an ER-40 collet. Here's a pic:
As this is made on the lathe, it is real accurate. Will be nice as my 3-jaw chuck is sloppy.
I made a ring that attached with 3 screws to clamp the collet. It worked OK, but had some play. I decided to use a commercial ER-40 clamping nut. this has a 50mm x 1.5mm internal thread.
So grabbed my lathe manual, looked up a thread pitch of 1.5mm and started to cut the thread. I had checked the gears several times. The pitch was wrong. Turns out the entire table was wrong. The manual was written in 1937, so metric threads were few and far between
No now what?, I don't want to start over especially since I don't have any more stock.
I first tried TIG welding. That was a failure and all I have is 4043 wire. The 6063 takes a huge amount of heat. FInally get a small weld pool and the 4043 wire will melt long before you get near it.
So, plan B. Grabbed the MIG and some 5356 0.9mm wire. Some short tests worked, but longer welds ended up with a birdsnest. I had forgotten I had switched to a 0.9mm liner. I switched to the 1.2 liner and it worked well.
I set up the lathe as a weld positioner; heck the chuck was already mounted on it. This required making a plug to fit the far end of the spindle to allow the work lead to connect but still spin.
Set the lathe to about 6 RPM. Was hard to see and follow; maybe I should have clamped the torch in the carriage and set the gears to 4 TPI. Would have been full robotic weld.
Came out ok, had a few jitters and caused some small pits. Did have a 1/2 turn that I had moved too fast. So, cleaned up and touched it up manually. Since MIG starts cold, I would start on a high spot and then move to the low spots. That made it looked even lumpier.
Had just started cleaning it up and took a pic. I had a collet in the chuck to protect the taper and also prevent any chance of too much penetration.
Turned down to 50mm and the correct threads cut. I found a later manual. It had a different gear setup but was still wrong. Was easy to figure out though as it was off by a factor of 2.
All finished. Put in a test piece and could not measure any offset. The chuck will hold work from 3/16 to 1" (4-25mm).
The full details of how i mad ethe chuck are shown here.