drilling a hole 12inches deep???

   / drilling a hole 12inches deep???
  • Thread Starter
#21  
If you're interested, I have a spare 1-7/8" drill you can have. The flutes are right at 6" long, so you could get the majority of
your hole drilled, then use your boring bar.

View attachment 425686
View attachment 425687

Not sure of the taper, but you could possibly turn it to fit your tailstock...

Feel free to PM your address, and the USPS will be thrilled to deliver!

Tim

Tim, I tried to PM you, but for some reason every time I click send message, or preview message, I get redirected to a comcast site trying to sell me something. Maybe you can PM me and we'll see if we can communicate that way

Sent email
 
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   / drilling a hole 12inches deep??? #22  
Originally Posted by Brad_Blazer
Here's another vendor. They had the best shipped price I could find for a couple of pieces of DOM I recently ordered.
The Best Place To Buy Metals & Industrial Supplies Online | Buy Metals Online | Buy Industrial Supplies Online | Cut to Size | No Minimum Order | CNC Laser Cutting | CNC Machining
2 ft of 2.5in od x 2in id =$31.40 +shipping, I wasted more time than that trying to cut it. Should of just ordered it to start with

Been there, done that, got the tee shirt!
 
   / drilling a hole 12inches deep??? #23  
Originally Posted by Brad_Blazer
Here's another vendor. They had the best shipped price I could find for a couple of pieces of DOM I recently ordered.
The Best Place To Buy Metals & Industrial Supplies Online | Buy Metals Online | Buy Industrial Supplies Online | Cut to Size | No Minimum Order | CNC Laser Cutting | CNC Machining
2 ft of 2.5in od x 2in id =$31.40 +shipping, I wasted more time than that trying to cut it. Should of just ordered it to start with

Been there, done that, got the tee shirt!
Yes - but it is more satisfying to know you could do it. Still next time you order it because you have already proved it to yourself!
 
   / drilling a hole 12inches deep??? #24  
If you have already chewed a 1" hole from each end you are nearly there.

Instead of making a long boring bar to bore the work conventionally, think laterally: line bore.

Get a piece of 1" bar suitably long enough & centre drill each end. Cross drill this to take a HSS cutter ground as a normal boring cutter & secure with a set screw (grub screw in American?). Mount the 2 1/2 in stock on the cross slide, packing up to centre level & using milling type clamps to secure.
Mount the bar between centres & drive with a dog for a precision job, or just hold one end in the three jaw & use the tail centre the other end. DON'T Use the cross slide to apply cuts lock it to be safe, but use the self act for the boring. Increase boring diameter by extending the cutter after each pass (measure with mike/calipers)
 
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   / drilling a hole 12inches deep???
  • Thread Starter
#25  
If you have already chewed a 1" hole from each end you are nearly there.

Instead of making a long boring bar to bore the work conventionally, think laterally: line bore.

Get a piece of 1" bar suitably long enough & centre drill each end. Cross drill this to take a HSS cutter ground as a normal boring cutter & secure with a set screw (grub screw in American?). Mount the 2 1/2 in stock on the cross slide, packing up to centre level & using milling type clamps to secure.
Mount the bar between centres & drive with a dog for a precision job, or just hold one end in the three jaw & use the tail centre the other end. DON'T Use the cross slide to apply cuts lock it to be safe, but use the self act for the boring. Increase boring diameter by extending the cutter after each pass (measure with mike/calipers)

I would have to see that done to know what your talking about. I suppose I could clamp the stock in the cross slide and mount the boring bar in my 4jaw and off set the bar off center and line bore it that way, I could use the cross slide to feed the stock to the bar. Not exactly sure how I would center the stock up with the lathe centers to make that work. I am sure the set up time would take a while. Also not sure the boring bar wouldnt sling out of the chuck and dent my hard head. With my limited experience with machining, I think it might be safer if i didnt start trying to rig up something I aint sure about and havent seen done before.
 
   / drilling a hole 12inches deep??? #26  
If you have already chewed a 1" hole from each end you are nearly there.

Instead of making a long boring bar to bore the work conventionally, think laterally: line bore.

Get a piece of 1" bar suitably long enough & centre drill each end. Cross drill this to take a HSS cutter ground as a normal boring cutter & secure with a set screw (grub screw in American?). Mount the 2 1/2 in stock on the cross slide, packing up to centre level & using milling type clamps to secure.
Mount the bar between centres & drive with a dog for a precision job, or just hold one end in the three jaw & use the tail centre the other end. DON'T Use the cross slide to apply cuts lock it to be safe, but
use the self act for the boring. Increase boring diameter by extending the cutter after each pass (measure with mike/calipers)

Pycoed, do you have any pictures of doing this? Would like to see your set up.
 
   / drilling a hole 12inches deep??? #27  
You are using the carriage of the lathe as a milling table. You are using the rotating bar in the lathe as a cutter support. Moving the crossfeed positions the workpiece relative to the lathe centerline, so once the piece is set, don't move it. All your "milling" feeds will be done by moving the carriage.

The cutter bar needs to be long enough for the whole workpiece to be on either side of the cutter, so for a 1' long sleeve, you would need a bar at least 2' long, with the cutter centered, plus a little bit more to be able to access the bit to adjust the "stickout" and advance the cutter. The bar needs a hole for a piece of HSS to go through, and one perpendicular for a setscrew (or even one from each side) to hold it in place. The other thing to remember is that for every .001 you extend the cutting bit, your diameter increases by .002.

I have done this exactly once. It was just a "cleanup" cut to get a centered hole in a casting that had been worn out of round, and didn't need to be precise...which is good because it sure wasn't pretty. I have no pictures of the setup or results.
 
   / drilling a hole 12inches deep??? #28  
If you have already chewed a 1" hole from each end you are nearly there.

Instead of making a long boring bar to bore the work conventionally, think laterally: line bore.

Get a piece of 1" bar suitably long enough & centre drill each end. Cross drill this to take a HSS cutter ground as a normal boring cutter & secure with a set screw (grub screw in American?). Mount the 2 1/2 in stock on the cross slide, packing up to centre level & using milling type clamps to secure.
Mount the bar between centres & drive with a dog for a precision job, or just hold one end in the three jaw & use the tail centre the other end. DON'T Use the cross slide to apply cuts lock it to be safe, but
use the self act for the boring. Increase boring diameter by extending the cutter after each pass (measure with mike/calipers)

Pycoed, do you have any pictures of doing this? Would like to see your set up.

I don't have a picture of my setup - last time I did it I was boring the base of an old Redding shotgun reloading press I'd been given. This was only about 4" wide, but the principle is the same. I did find this set up, which gives the general idea, though a LOT newer (& smaller) than my lathe !

linebore.jpg
 
   / drilling a hole 12inches deep??? #29  
keith fenner on youtube had a good video of line boring on his lathe.
 
   / drilling a hole 12inches deep??? #30  
keith fenner on youtube had a good video of line boring on his lathe.

Ah! Of course I should have remembered that - he has loads of good stuff on his Youtube channel - hours of fun!
 
 
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