|
|
This is made out of the remains from a home built driveway gate opener I made about 25 years ago. The drive for it was a cheap garage door opener which I converted. It only lasted 20 years, then the circuit board fried when a slug crawled across it. Highly conductive animals those slugs. I put the 40 to one gear reducer and the remains of the garage door opener under the bench five years ago and was very recently going to throw out at least the burned out garage door opener. Then I got thinking it would be nice to have a rotating table for doing circular or semi circular welds and also for cutting nice circles with the plasma cutter. I plan to make an adjustable arm that will hold the plasma cutter at a fixed point above the turntable on any radius up to about 8". That should produce nice smooth cuts and a perfect circle.Total cost was $1.83 cents for four 3/8" bolts. And maybe 75 cents worth of er70s-2The rest was a left overs from various projects.Speed is variable from about 1/4 rpm to about 15 rpm.Might add an on/off foot pedal, could be handy for gtting the puddle started when tig welding. My neighbour gave me an old but working one last week, so it won't run the cost up! Attached Images
Reply:Here's a little clip
Reply:I like it. Keep your eyes peeled for a dead MIG or wire feeder with a good drive motor and controls that you can reconfigure to drive it. I've got one that plans call for doing just that with it.Nice job. MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Not bad. It's always nice to make junk laying around useful. I can tell you from experience that you might have a little problem with speed control at the lower speeds. It sometimes tends to change. I ended up putting a second chain reduction in mine to help with that. But the real cure would be a true speed control on the driving motor. I should get some pics of my positioner and post them some day.Millermatic 252XMT 304'sDynasty 280DXHypertherm PowerMax 1250Miller Trailblazer 302 EFIOptima PulserXR feeder and XR Edge gun and more athttp://members.dslextreme.com/users/waynecook/index.htm
Reply:Originally Posted by duaneb55I like it. Keep your eyes peeled for a dead MIG or wire feeder with a good drive motor and controls that you can reconfigure to drive it. I've got one that plans call for doing just that with it.Nice job.
Reply:I'm going to be doing a pile of circular welds with it next week, I have five man gates to build, all with round tubing for the pickets. I'll report back if there is a problem with the feed speed. As near as I can tell it runs perfectly right down to an extremely slow table RPM. Total reduction is 160 to one so it doesn't take much torque from the drill to make it move.Things might be different with some weight on there though.
Reply:On mine I see the problem mostly when welding. It seems to slow down exactly when I strike a arc. I'm sure some of it is the bearing / ground. I used a bronze bushing on pipe for my bearing and my swivel for the ground.Millermatic 252XMT 304'sDynasty 280DXHypertherm PowerMax 1250Miller Trailblazer 302 EFIOptima PulserXR feeder and XR Edge gun and more athttp://members.dslextreme.com/users/waynecook/index.htm
Reply:I'll say that most positioners I've seen are always some hokey thing made from left over chucks, or plates some left over motor and a gear reducer.shoot, at a company I worked at we made a positioner made from an old lathe bed complete with chuck. We slapped on a digital tach so we could confirm the speed, and called it a day. It was used to weld $100K rocket components for NASA, mind you we had a complete automatic arc gap unit and about 40K in controllers wire feeders and weld machine hooked up to it, but you woulda thought it was murder if they had to pay more than $0 dollars to rotate 15 foot long rocket componentWelding EngineerCertified Scrap Producer
Reply:Tried it out last night, it works really well. It is a big improvement over my old method of circluar welding which was to have my brother slowly turn the object as I was welding.I like it better for stick, mig and plasma than for TIG. The first three are all processes that work well with a constant steady and smooth rate of travel. With TIG I have spent all of these hours learning to step and pause then dab the rod to get the dimes. Now with a constant steady motion of the weld positioner I have to unlearn the step and pause for these circular TIG welds.
Reply:Originally Posted by irish fixitOn mine I see the problem mostly when welding. It seems to slow down exactly when I strike a arc. I'm sure some of it is the bearing / ground. I used a bronze bushing on pipe for my bearing and my swivel for the ground.
Reply:worntorn, It's not a bit hokey if you don't have one, nice work. You'll keep updating and fiddling with it as you see fit.Matt
Reply:Thanks Matt
Reply:Originally Posted by worntornTried it out last night, it works really well. It is a big improvement over my old method of circluar welding which was to have my brother slowly turn the object as I was welding.I like it better for stick, mig and plasma than for TIG. The first three are all processes that work well with a constant steady and smooth rate of travel. With TIG I have spent all of these hours learning to step and pause then dab the rod to get the dimes. Now with a constant steady motion of the weld positioner I have to unlearn the step and pause for these circular TIG welds.
Reply:Hokey is downright upstanding in these parts. Sincerely, William McCormick
Reply:Originally Posted by Matt_MaguireI use one or the other of the below brushes (each good for 150A at 24V) depending on grounding to the spindle shaft or a shaft mounted ground plate. They only add about 2ohms to a ground setup.I always isolate any spindle bearings and the ground setup from the frame of any machine.I have seen bronze bushings used to ground the spindle and they seemed to work OK. I've also seen bronze brushes (isolated) against the faceplate (also isolated).
Reply:Originally Posted by irish fixitYeah I thought about that but wanted to keep it simple. I've got some brushes that I'm pretty sure are for a SA200 that would of worked. I've always read about people saying to not use bearings is one of the reasons I used the bushings. The truth is I've had pretty good luck with tapered roller bearings.
Reply:The high frequency and AC weld current, will create power between two separate conductors attached to the same terminal, if they are not both of the same material and length. Pretty wild stuff actually. Sincerely, William McCormick
Reply:Originally Posted by William McCormick JrThe high frequency and AC weld current, will create power between two separate conductors attached to the same terminal, if they are not both of the same material and length. Pretty wild stuff actually. Sincerely, William McCormick
Reply:Originally Posted by Matt_MaguireI don't do it to save the bearings. I do it to provide only one clean electrical path for the ground. A system with multiple ground paths usually works ok with mig (sometimes not) but can often cause arc-blow with SMAW and cold wire TIG.They now have special fluid compounds that are supposed to carry current in rotary couplings but I have no experience with that.Anyway when I set up the ground system or tune one up, I hook a scope up with a battery through a small resistor and I want to see a clean flat trace while it is rotating.Matt
Reply:That is a very simple and well thought out system that looks like it works very well! Thanks for the idea! It doesnt have to cost big bucks to make life easy!
Reply:I made an adjustable pivot arm for it so that I can positon the plasma cutter on there for circle cutting.I also added a 1/4" hole for a centre pin so that things can be positioned on the plate like an old record player. This way I have an exact centre on the cut piece to work from later.Here it is cutting two plates at once 3/16" x 14" dia for a piece of Bakery production equipment I'm building for a customer. Attached Images |
|
发表于 2021-8-31 23:36:32