Denford Lathe Retrofit

[DICKEYBIRD]

That's a great solution Jim...looks real sturdy and easy to adjust.

Thanks for the Motion Ind. tip, looks like they have a sheave.

[outback]

I got the spindle running with the variable frequency drive I bought on Ebay. Decided at the last minute to add a motor contactor with overloads for the variable frequency drive. A little added safey and insurance. later I will add buttons to to STOP and REVERSE the spindle. Sweet running machine. Very quiet.



VFD close up

Click for large pic

contactor and overload. Outlets for computer and cnc control

Next the controller build then it should be play time
Jim

[DICKEYBIRD]

Yer killin' me Jim; it's lookin' GOOD! I wish I was that far along. Are you going to put on a spindle speed sensor & disc? Does your control have the ability to control the VFD/motor speed?

Between work and pesky side jobs I got nothing done on mine other than getting a few more parts in. Your Motion Ind. tip really paid off. I just received a 10 groove J series 2.8" sheave and the matching 5/8" taper lock hub to fit my motor. That should give me close to 2000 rpm top speed if needed and I hope enough grunt at lower speeds. Dry runs with the Baldor DC motor & KB speed control sure feel powerful. We'll see later.

Keep the pics a-comin'...I need the motivation!

[John Stevenson]

Yer killin' me Jim; it's lookin' GOOD!

Keep the pics a-comin'...I need the motivation!

Too much motivation

Mine is well down the list of machines to do but just been down to Leicester today where the machine is stored and stared longingly at it sat 15 foot up in the air on racking.

Mine is complete but the controller is dead. Just realised today its the model fitted with an air chuck.

Where Jim's has the menu ? plate below the word ORAC on the headstock, mine has two push buttons marked open and close.

Only problem with this is you can't use long lengths because of the chuck mechanism so it's only a chucker but it does have a 3 jaw sat on the base plate.

[DICKEYBIRD]

John you need to root around in those dusty ol' shops you wander in & out of and find you, me & Jim a nice Denford toolchanger each to play with.

That's not much to ask for and I can wait 'til Christmas.

[John Stevenson]

Milton,
PM sent.

[outback]

I'm using a breakout board made by Bob Cambell designs. I think it will do speed control but I'm not going be concerned about spindle speed control by the controller for a while. I mounted the VFD in a convenient place so I can control the spindle RPMs myself.

The VFD has a speed control knob in the front. I'm going to add push buttons for forward and reverse near the VFD. However, I will start and stop the spindle from the control.

I'll start wiring the control this weekend. See how it goes.

I dawned on me why the Denford lathe is so smooth and quiet. The lathe
has no gears. Feeds, speeds and spindle is all controlled electricaly.
Jim

[John Stevenson]

I have never taken any pictures of my ORAC as it's never been here, bought then farmed out for storage. Came from a college in Oxford.

Was looking thru some folder last night for a drawing and found this.



Not a brilliant picture as it came off the auction site and has been blown up. I saved it and printed it out for when I went to collect it.

The guard is interesting in that it slides on a rear rail and you can put it where you want but you need the original base and back for it to work correctly.

[DICKEYBIRD]

That tinted plastic guard is pretty cool. I got the base/splash panel with mine but it didn't come with the guard. I'll probably make one later on if I can get a deal on some Lexan. It did come with a state of the art audio cassette player and stereo speakers though.

The base is a sturdy, well-built structure built out of heavy sheet metal. I removed the speakers and left the grilles for cooling air inlets. While removing them and the misc. brackets & electrical fittings, I was impressed with the high quality hardware & workmanship. Every socket head screw & nut was high grade and had its proper flat washer & star lock washer in place. Not a one missing in the pile of stuff I removed. Those Yorkies do good work.

I did notice a little weak spot (IMHO) in the design of the base though. The 2 spots where the lathe bolts to the base had the paint fretted off indicating some relative movement between the two. The top is heavy gauge but is unsupported between the hinged back panel and the front allowing it to flex. I've never seen or heard a "stock" one run but I'd bet it tends to resonate & jingle at certain speeds.

I'm going to bolt in a couple angle iron braces under the top, across the short direction near the mount pads with flat bar braces connected to a couple more angle iron braces across the floor. I may use a big chunk of the freebie 1/2" alum. plate I lucked into and bolt it to the floor as a heatsink to mount all of the electrical stuff onto. My Denford MicroMill is done that way and it works well. I'm fairly obsessive when it comes to keeping electrical widgets as cool as possible.

ps: I'll say it for you John: "Get yer bloody finger out and int' shop. Finish yer bleedin' girlie-man side work and get on with some real work!"

[Euph0ny]

With that shield, it does look like Orac!

Cool!! BBC - BBB7*




*BBC - Bring Back Blake's 7 :-)