Announcement
Collapse
No announcement yet.
What did you do today?
Collapse
X
-
“Maybe less Caffeine.“
Is this English? Can’t compute. LOL"Good judgment comes from experience, and often experience comes from bad judgment" R.M.Brown
My shop tour www.plastikosmd.com
Comment
-
-
Did the finishing touches on the lathe cross slide nut.Here it is all done with mounting holes,adjusting threads and split and the lubrication hole in the middle.
The channel in the saddle casting that the nut rides in was cast too shallow from the factory.The original nut they just milled the top off until it cleared the casting which had the threads showing and ultimately caused the original nut to fail.So I added 3/16" of material to the Z dimension of the nut to correct that issue,but what to do about the depth of the channel?It needed to be milled deeper to clear the nut,but it's a big casting and not an easy part to remove and replace.
The channel bottom had 1/16" clearance at the far end and was 3/16 too shallow in the near end.So I dug out my old woodworking router,a Bosch 1604,took the plastic subase off and chucked a 1/4" four flute carbide endmill in it.I started at the shallow end and took 1/16" deep passes working my way towards the far end.It took me about 45 minutes and three cutter changes,but I finally got there.
Not suprisingly all of the cutter damage occured due to sand embedded in the rough cast surface.With each cutter change I would start the new pass in a previously cleaned area to limit cutter wear.Now hat this hurdle is cleared I can hopefully go back together with it.
I just need one more tool,just one!
Comment
-
-
Originally posted by wierdscience View PostDid the finishing touches on the lathe cross slide nut.Here it is all done with mounting holes,adjusting threads and split and the lubrication hole in the middle.
The channel in the saddle casting that the nut rides in was cast too shallow from the factory.The original nut they just milled the top off until it cleared the casting which had the threads showing and ultimately caused the original nut to fail.So I added 3/16" of material to the Z dimension of the nut to correct that issue,but what to do about the depth of the channel?It needed to be milled deeper to clear the nut,but it's a big casting and not an easy part to remove and replace.
The channel bottom had 1/16" clearance at the far end and was 3/16 too shallow in the near end.So I dug out my old woodworking router,a Bosch 1604,took the plastic subase off and chucked a 1/4" four flute carbide endmill in it.I started at the shallow end and took 1/16" deep passes working my way towards the far end.It took me about 45 minutes and three cutter changes,but I finally got there.
Not suprisingly all of the cutter damage occured due to sand embedded in the rough cast surface.With each cutter change I would start the new pass in a previously cleaned area to limit cutter wear.Now hat this hurdle is cleared I can hopefully go back together with it.
http://bbs.homeshopmachinist.net/att...7&d=1550422611Location: Helsinki, Finland, Europe
Comment
-
-
Originally posted by RMinMN View PostMost routers would be able to cut metal but most run too fast so your cutter speeds are too high and wear out quickly. Putting a speed control on the router might work better.Last edited by 754; 02-17-2019, 01:14 PM.
Comment
-
-
Originally posted by 754 View PostWeird science m on a lot of machines the nut is split vertically. Then it allows a bit of backlash to get taken out later on, without excessive drag.
Comment
-
-
Originally posted by 754 View PostWeird science m on a lot of machines the nut is split vertically. Then it allows a bit of backlash to get taken out later on, without excessive drag.
The way this lathe was assembled was horrific.The centerline of the nut was supposed to be 31mm from the mounting face to the center exactly.The nut they had in there was 32mm,the only reason it ever worked is because the leadscrew assembly is made up of four parts all pinned together.It's about 30" overall length,so the screw assembly was having to flex for the thing to work at all.Surpirsing for an Italian built machine.I just need one more tool,just one!
Comment
-
-
Originally posted by RMinMN View PostMost routers would be able to cut metal but most run too fast so your cutter speeds are too high and wear out quickly. Putting a speed control on the router might work better.I just need one more tool,just one!
Comment
-
-
Originally posted by plunger View PostI would think the way it was cut would take no backlash out but would just cause drag.If it would have been slit the other way it would compensate for nut wear because you can pinch the nut to make up for wear.? Or am i missing something.?
The leadscrew has some wear,so this won't be a perfect fix,just one that's a lot better than what it was before.I just need one more tool,just one!
Comment
-
-
Sounds old fashioned but a cold chisel would have been suitable for this sort of non precision job and got below the sand at least to start it off.
On an Acme (sloping side) thread a longitudinal slit works using the whole nut length whereas the vertical slit means only half the nut length is in action for each direction.
Comment
-
Comment