Wasn’t sure what forum I should post this in, so Mods please move if needed…
As much as I would dearly LOVE to have a proper milling machine, current finances won’t allow that to happen for at least another year . So, my next best option was to buy or make a milling attachment for my little Craftex 7x12. I looked at the one Busy Bee sells specifically for this lathe http://www.busybeetools.com/products/milling-attachment-for-lathe-cx704.html , but wasn’t overly impressed with it for the price, not to mention the geometry was wrong for a couple specific jobs I needed it for. Well that settles that then…guess I’ll be making one.
Searched around the ‘net looking at different designs, but most (if not all) had the vice/material hanging wayyyy out over the cross-slide and in mid-air…not the most rigid configuration and uses up a lot of space - 2 commodities the 7x12 doesn’t have a lot (or enough) of to begin with. So I took a bunch of measurements of the lathe, sat down at the computer and proceeded to draw up a set of plans that would work for what I wanted to do. Once I was satisfied with the design (after numerous tweaks) I picked up some metal from Metal Supermarket in Ottawa and it was finally time to “git-r-done”.
Like most designs I have seen, I am using the lathe’s compound mounted to a ½” thick angle plate for the Z axis, and a small, used milling vice I picked up attached to the compound via an adapter plate. Right off the bat I needed to mill a pocket in the bottom part of angle plate and another pocket on backside of adapter plate to fit the tool post section of compound, but how does a guy with no milling capabilities yet go about this? Now, normally I would try to jerry-rig some sort of contraption together, hack my way through it and just try to deal with what would undoubtedly be a sub-par job…sounds stupid I know, but I would prefer to struggle (to a point, mind you) with an inadequate tool I built myself rather than bother other folks with my piddly projects or problems. This time around though, I wanted/needed the job done right and accurately if I wanted any hope of it being accurate once done. Sometimes a fella has no choice but to ask for help. Thankfully and luckily (for me anyways), forum member Greg (a.k.a. f350ca) only lives about 30 minutes from me and said he could help me out. I am SO glad he did! Actually, he did ALL the major machine work for me seeing as he already had it set up, squared, etc - all I did was supply the drawings and the metal. Very nice work, VERY fair price and a helluva nice guy as well! Thank you once again, sir!
Once I had all the pieces back home, I drilled/tapped my compound 10-32 (6 in total) to hold adapter plate and started assembling. The low profile SHCS’s you see are just to keep swarf out of holes while working on the rest.
All pieces finished and ready to assemble. Angle plate, adapter plate and clamp nuts all made from ½” thick CR 1018 flat bar:
I kinda figured there would be a hiccup somewhere along the line (seems there always is...), and true to form there was, albeit a minor one - the 2 holes in vertical section of angle plate to attach compound are tapped ¼”-28 and wouldn’t ya know it, all I have left here is 20 TPI…not a single 28 TPI to be found anywhere…. Will get a bunch later today. Anyways, here it is all assembled and (mock) mounted to lathe:
Centerline of mounting bolts on cross-slide for compound lines up with center of vice mounting plate…just enough room to allow vice to fit in pocket. FYI, I needed that pocket in order to lower vice far enough to use my ½” dovetail cutter on a 1” thick breech…leaves a whole 0.060” to spare!!
I still have a few little things to do like mount a dial indicator for precise Z axis measurements (learned the hard way not to trust the graduated dials on a cheap, Chinese lathe - sometimes they work, sometimes not so much…on mine anyways) and maybe paint or most likely blue the pieces to slow down the rusting process. I admit that for a 7x12 she’s a fairly bulky unit (just a hair over 11lbs) and might be a bit cumbersome at times depending on what I’m doing, but nevertheless it should prove to be a useful addition for what I want to do until I can afford a proper mill.
Now, to just find the time to use it…
Thanks for looking, hopefully it’ll give some ideas to someone else in the same boat as me!
As much as I would dearly LOVE to have a proper milling machine, current finances won’t allow that to happen for at least another year . So, my next best option was to buy or make a milling attachment for my little Craftex 7x12. I looked at the one Busy Bee sells specifically for this lathe http://www.busybeetools.com/products/milling-attachment-for-lathe-cx704.html , but wasn’t overly impressed with it for the price, not to mention the geometry was wrong for a couple specific jobs I needed it for. Well that settles that then…guess I’ll be making one.
Searched around the ‘net looking at different designs, but most (if not all) had the vice/material hanging wayyyy out over the cross-slide and in mid-air…not the most rigid configuration and uses up a lot of space - 2 commodities the 7x12 doesn’t have a lot (or enough) of to begin with. So I took a bunch of measurements of the lathe, sat down at the computer and proceeded to draw up a set of plans that would work for what I wanted to do. Once I was satisfied with the design (after numerous tweaks) I picked up some metal from Metal Supermarket in Ottawa and it was finally time to “git-r-done”.
Like most designs I have seen, I am using the lathe’s compound mounted to a ½” thick angle plate for the Z axis, and a small, used milling vice I picked up attached to the compound via an adapter plate. Right off the bat I needed to mill a pocket in the bottom part of angle plate and another pocket on backside of adapter plate to fit the tool post section of compound, but how does a guy with no milling capabilities yet go about this? Now, normally I would try to jerry-rig some sort of contraption together, hack my way through it and just try to deal with what would undoubtedly be a sub-par job…sounds stupid I know, but I would prefer to struggle (to a point, mind you) with an inadequate tool I built myself rather than bother other folks with my piddly projects or problems. This time around though, I wanted/needed the job done right and accurately if I wanted any hope of it being accurate once done. Sometimes a fella has no choice but to ask for help. Thankfully and luckily (for me anyways), forum member Greg (a.k.a. f350ca) only lives about 30 minutes from me and said he could help me out. I am SO glad he did! Actually, he did ALL the major machine work for me seeing as he already had it set up, squared, etc - all I did was supply the drawings and the metal. Very nice work, VERY fair price and a helluva nice guy as well! Thank you once again, sir!
Once I had all the pieces back home, I drilled/tapped my compound 10-32 (6 in total) to hold adapter plate and started assembling. The low profile SHCS’s you see are just to keep swarf out of holes while working on the rest.
All pieces finished and ready to assemble. Angle plate, adapter plate and clamp nuts all made from ½” thick CR 1018 flat bar:
I kinda figured there would be a hiccup somewhere along the line (seems there always is...), and true to form there was, albeit a minor one - the 2 holes in vertical section of angle plate to attach compound are tapped ¼”-28 and wouldn’t ya know it, all I have left here is 20 TPI…not a single 28 TPI to be found anywhere…. Will get a bunch later today. Anyways, here it is all assembled and (mock) mounted to lathe:
Centerline of mounting bolts on cross-slide for compound lines up with center of vice mounting plate…just enough room to allow vice to fit in pocket. FYI, I needed that pocket in order to lower vice far enough to use my ½” dovetail cutter on a 1” thick breech…leaves a whole 0.060” to spare!!
I still have a few little things to do like mount a dial indicator for precise Z axis measurements (learned the hard way not to trust the graduated dials on a cheap, Chinese lathe - sometimes they work, sometimes not so much…on mine anyways) and maybe paint or most likely blue the pieces to slow down the rusting process. I admit that for a 7x12 she’s a fairly bulky unit (just a hair over 11lbs) and might be a bit cumbersome at times depending on what I’m doing, but nevertheless it should prove to be a useful addition for what I want to do until I can afford a proper mill.
Now, to just find the time to use it…
Thanks for looking, hopefully it’ll give some ideas to someone else in the same boat as me!