Greetings All,
Just thought I'd share a little metal working "Fun" I recently experienced. But first, here's a web-site with a whole bunch of pictures taken during the project:
I'm interested, so I say "Sure what are we building?"
Shad: "You know that new roller coaster going in, well we got 14 days to fabricate and install the stainless load / unload handrail, gates, and pneumatic controls."
Me: "Uh, can we do that in 14 days?"
Shad: "The material arrives today, we start tonight, and money is no object"
Me: "I'm in! What do you need me to bring?"
Shad: "You got a TIG welder, bring it, and whatever else you can think of!"
And so it begins :0
(BTW, I should mention, I'm a computer geek by trade, metal worker by hobby..)
Some Fun Moments:
#1 The Lathe: (which will probably cause tears of laughter, and large amounts of concern from the audience)
Shad says "James, you can run a lathe, right?" I got a little metal lathe at the house, and I use it a lot, so I say "Sure."
Shad: "Good, go make these bushings" So, I need to make 48 bushings that are 2" OD, 1"ID, 2" Long, face the ends and chamfer the corners, then drill and tap them for set screws. I start cutting the 304 stainless 2" bar stock to length in the band saw, while I go have a look at his lathe.
Its a big lathe, with no name, covered in crud, has a bunch of knobs and levers, and a strange foot pedal near the floor. So I ask Shad "Hey, what do all these levers and knobs do?" Shad says "I don't know, I only use that thing to drill holes in round stuff, go figure it out..." "You got a manual?", I ask, "NOPE"
OH BOY.. so I move the carriage off to a safe distance, turn on the power and it spins up. First thing I do is step on the big foot pedal, NEAT it's turns off the power and works like a brake (until you take your foot off it). At this point, I realize I need to make a very big mental rule "NEVER muck around with the chuck unless both feet are firmly on the concrete and the power is off!"
Next I start playing with the levers on the head. I figure out the big one selects overall spindle speed, and the other two levers on each side work like Hi/Lo range selectors. BTW, did I mention all the lettering was worn off for these levers? After that I study the 4 knobs and an additional lever towards the bottom of the head. If figure this has got to do something with threading, so I ignore them for the moment.
Now I start studying the carriage, which has another variety of levers.. I recognize what all the hand wheels do, but there are a bunch of levers I have no idea about, and none are labeled..
On the right side of the carriage is a red lever, I pull it and the lath spins backwards. Hmm Don't need that lever, So I move on.
Towards the bottom right is a lever that has two positions, It's up, so I push it down, nothing happens, so I put it back in the up position. Below the cross feed handle is another lever, it has three positions, and is currently in the center. I push it to the top position, nothing, I put it in the bottom position, nothing, I put it back where I found it. I figure that the three position lever must control the power feeds somehow, and maybe the bottom lever turns the power feed on / off. So I put the three position lever in the up position, and push the bottom right lever down. HOT DAMN, I got the cross feed to move! I step on the brake, and put the three position lever in the bottom position, now the carriage is moving left, Oh YEA :)
Now I'm making progress, but I can tell that the power feed speed is ridiculously high, like it is trying to cut threads instead of doing a finish cut. SO back to the bottom set of knobs on the head. After wiping the grime off, I can actually see some labeling here. The big selector lever has 8 positions, One knob says "Inch / Metric", two knobs on the left are labeled A/B and C/D, and the fourth knob has some red symbols. So I flip the knob with the red symbols, and a new shaft of the bed start to turn, that's different.. Now when I engage the power feeds, I get decent cuts. (BTW, I never did figure out how to adjust between finish cuts and rough cuts on the power feed, but oh well)
All in all, it took about an hour to get the lathe setup to do what I wanted, and in the end I could Bore the 1" hole, face and chamfer one end, flip the part in the chuck, cut the other end to finish length, face and chamfer that end, all in about 10 minutes, using an insane amount of cutting oil, and lots of smoke while boring..
Now that was Fun! :) Towards the end of the job, I even got to turn some threads on the old girl, which came out fairly well after wiping the grime off the face plate that described how to setup for different thread pitches.... Cool stuff :)
#2 The Iron Worker This is a fun but short moment. Shad has an "IronWorker" which is a combination nibbler, shear, punch. We've got a bunch of
1/2" thick x 4" wide 304 stainless bar stock to cut to length, punch 2 holes in for concrete anchors, drill and tap two holes for a bearing block, and finally plasma cut out the opening for the shaft to go thru.The Ironworker makes quick work out of shearing the stock to length, next it is time to punch the 3/4" holes thru the 1/2" thick stainless flat stock. I ask Shad if the Ironworker is up to the task, he says "I don't know, but do you want to drill those holes instead?" I reply with an "ahhh NO!"
So I setup for punching, slide the first piece into place, which barely fits between the table, and the safety guard. I stand back and press the foot pedal, and the machine groans for a moment and "BANG" which sounded like a gun shot....
EVERYBODY stopped what they were doing and turned to look! The "I have no idea how many ton" Ironworker jumped, the floor shook, but it did punch the hole! I don't even want to think of the forces involved, but it punched all the holes and nobody, nor anything was hurt. Now that was almost as much fun as figuring out the Lathe.
#3 The death and resurrection of my NEW Tig welder.
SO, the team is rocking and rolling on handrail Fab.
Rich is running the band saw, cutting stainless tube to length
Ron is notching the ends of the tubing on the nifty coping sander
Shad is Assembling and tack welding the handrails using my 6 month old Miller 180SD tig machine.
Steve is in the TIG room finish welding what Shad has tack welded together.
I'm Machining, punching, plasma cutting, and fabricating bearing mounts and lever arms.
Now, its Saturday, just after lunch, and you know that feeling you get when your using someone else's expensive tool, and it stops working, and appears broken? We'll Shad walked up to me with that look in his eye. I asked him what's wrong, and he says "Your Tig welder isn't working." My first words are "Don't worry, its under warranty, so worse case we'll just be without a welder for a few days."
However, we don't have time to be without a welder, so I go have a look.
Here's the symptoms: In Tig mode, when you step on the pedal, the high freq starts up, and you get a 9 amp current flow according the to meter on the machine. It doesn't mater what you do with the pedal, or the amp setting on the welder, you get 9 amps, nothing more..
My fist thought is the rheostat in the pedal isn't working. To prove this, I switch over to Stick mode, and strike an arc at 180 amps DCEN, no problem, Then I try it in AC as well as DCEP. Good, looks like the machine is OK, just something odd with the foot pedal.
So I take the foot pedal apart, everything looks ok. I go to the truck and get an ohm meter, and the manual for the welder (which amazingly includes pinouts and schematics for both the machine and the foot pedal!)
I start by ohming out the foot pedal cable, and sure enough one wire is showing open, and two others are shorted together. So I start inspecting the cable, at first glance I don't see anything, but as I pull the cable thru my fingers, I feel a flat spot. I peel back the insulation at the flat spot, and yup I see bare wires inside.
Looks like something heavy either fell onto, or rolled over the cable and crushed the wires inside. Probably happened as we were cleaning up to goto lunch. No big deal I think, I'll just patch up these wires and were back in business. Well, It wasn't that simple...
After fixing the cable, the damn thing still didn't work, having the same symptoms it did before. I re-checked the cable with the ohm meter and everything was looking right.
Back to the schematics, where I see the foot pedal has two parts to it. The first part is a contact switch, which turns on the High Freq and enables the current to flow. The second part is just a simple rheostat attached between the foot pedal and the control circuit board. Well the contact switch appears to run off 25vdc, where the rheostat is running off some unknown and separate voltage. When the wire's were crushed, I guess it sent the 25vdc back down the line to the control board, where it wasn't welcomed!
Thinking maybe there is a fuse somewhere on the one and only circuit board inside the welder, I pulled the skins off the machine and removed the circuit board. (BTW, its Saturday, and we NEED a running TIG welder! The only other alternative was to goto the job site, pick up the Max 40 Diesel welder, bring it to the shop, attach the high freq box, and listen to that damn thing run all day.)
So there I was with my 6 month old TIG welder, all the covers off, and I've got the one and only circuit board pulled out sitting on a table, looking for fuses. There aren't any blown fuses.. So I start looking at components around where the foot pedal cable connects. When I'm troubleshooting electronics, I always start by checking diodes, and what do you know, I find one diode that is shorted out both ways, and that diode is connected between ground and the pin from the rheostat on the foot pedal.
I run over to Radio Shack, grab a soldier sucker, soldering iron, some soldier, and a new Diode. Back at the shop, I pull the suspect diode out, and yes indeed, it is shorted out internally. I replace the diode with the one from Radio shack, put everything back together, and I'll be damned, the TIG welder is back up and running again!
I think it's at this point that Shad made one of his more comical comments, which went something like this: "James, if you had just fixed a walkie talkie or some computer, I'd call you a MAJOR GEEK, but you fixed a WELDER, damn that's cool!" :)
Anyway, the job's done, it was a good way to spend two weeks vacation, the coaster is rolling, and if you ever find yourself in Tampa, waiting in line to ride the new roller coaster, right before you get on, check out the stainless handrails, I helped make them :)
OH, and in an odd sort of way, the members of R.C.M. helped as well. Had it not been for the time I spent over the years reading all the posts by the group members, there is no way in hell I'd have been able to figure out this stuff. So THANK YOU R.C.M !!!
Take Care, James Lerch
Press on: nothing in the world can take the place of perseverance. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent. Calvin Coolidge