Re: DEC H9xx rack parts needed
> On Sep 16, 2017, at 7:44 PM, Chuck Guzis via cctalk > wrote: > > On 09/16/2017 03:21 PM, Steve Malikoff via cctalk wrote: > >> Yes I agree they both appear to be simple machining jobs. As a substitute >> for drill rod... > > I'm unclear why the recommendation has been for "drill rod" (i.e.tool > steel) for the parts that essentially hold the parts to a hinge together. > > It would seem that a plain 1018 cold-rolled steel would be strong > enough. For easy machining, even 12L14 would seem to be preferable, > although I don't know if that's legal in the EU, given the slight lead I just meant it in the sense of steel rod that's available in many sizes to good tolerances. You're right, for this application mild steel is certainly strong enough.
Re: DEC H9xx rack parts needed
On 09/16/2017 03:47 PM, Ethan Dicks via cctalk wrote: Worst case, if I can't resurrect the PC, I'll probably throw an Arduino on it and use modern Open Source tools for driving it (the LMC box has a DB25 with all the step and direction and endstop signals on it for Mach3 or Grbl or whatever). This sort of project would be perfect on this wee lathe. The pins would be trivial (just need to grind an HSS cutting bit with the profile you described), and the bushings not much harder (ordinary bit for the main diameters and the taper, then cutoff, then rechuck and cut down the face to get down to final length). -ethan There's also LinuxCNC for machine control. ( linuxcnc.org ) Jon
Re: DEC H9xx rack parts needed
On 09/16/2017 03:21 PM, Steve Malikoff via cctalk wrote: > Yes I agree they both appear to be simple machining jobs. As a substitute for > drill rod... I'm unclear why the recommendation has been for "drill rod" (i.e.tool steel) for the parts that essentially hold the parts to a hinge together. It would seem that a plain 1018 cold-rolled steel would be strong enough. For easy machining, even 12L14 would seem to be preferable, although I don't know if that's legal in the EU, given the slight lead content. Anyone care to shed some light on this? And if "Drill Rod' is the preferred material, what *kind* of steel? i.e. O1, S7, A2, D3, W1, M2? Just curious--unless the application is for a shaft subject to torsional loads or needing a cutting edge, I generally use cold-rolled mild steel--it's inexpensive and machines well. --Chuck
Re: DEC H9xx rack parts needed
Paul and others said >> On Sep 16, 2017, at 4:10 PM, Paul Koning via cctalk >> wrote: >> >> >>> On Sep 16, 2017, at 9:52 AM, Noel Chiappa via cctalk >>> wrote: >>> does anyone have any spare "pivot bushings" for the DEC H9xx series cabinets (H950, H960, etc)? (These are the short pieces with a conical top which fit over the hinge pins, at the bottom.) ... I could also use some more of the pins (particularly the kind with the hole drilled through them to take a roll pin) >>> >>> Someone asked for an image of these; here: >>> >>> http://ana-3.lcs.mit.edu/~jnc/tech/jpg/H9xxPinBushing.jpg >>> >>> is one. The pin in the picture is the kind without the hole at one end, but >>> they are otherwise identical. (Ignore the retaining ring on the pin; those >>> are easy to get, my local hardware store has them.) >> >> If you have a lathe, this looks like a very nice beginner's project. Start >> with a rod of the right diameter; a simple way to get such a rod is to buy a >> long bolt, because those are mostly not threaded. Failing that, get a >> length of "drill rod" from a metal supply outlet. Then all you need is to grind a tool bit (high speed steel) to form a narrow screwdriver-like tip to cut those grooves. Hold the rod in the lathe, cut the grooves in the right spots, cut the thing to length, done.> > Ok, I read that wrong. You were talking about the short thing. Still, > that's an easy project. Same idea. Start with a rod, grip in the chuck, > drill, cut bevel, cut the two diameters, then cut to length. Elementary > lathe operation books are easy to find; the South Bend Lathe manual that used to be reprinted by Lindsay Publications is very good. It's probably still available even though Lindsay unfortunately retired some years ago.> > paul Yes I agree they both appear to be simple machining jobs. As a substitute for drill rod (although not the same quality steel) you can use shafts out of old printers and photocopiers, I have a bunch of them I saved for just this sort of purpose. Often they have circlip grooves in them already, so some of the work is saved, but a fine tooth hacksaw will make a circlip groove whilst the lathe is spinning (frowned-upon workshop practice, I know). or just place it in a vice, saw, rotate the pin for the next few degrees and so on. Check the circlip for fir every so often. The bush looks pretty straghtforward. Between the one-off and the full CNC route is the form tool approach where the profile is ground in a piece of tool steel and then fed into the job. For very low runs a piece of drill rod can be cut then hardened, sure saves a lot of effort grinding. If some micrometer or digital caliper measurements of the pin and bush are available I'll draw it up for the list. :) Steve.
Re: DEC H9xx rack parts needed
On Sat, Sep 16, 2017 at 4:57 PM, Chuck Guzis via cctalk wrote: > On 09/16/2017 01:47 PM, Ethan Dicks via cctalk wrote: > >> This sort of project would be perfect on this wee lathe > You'll still need to center-bore the hole through the thing, which, > while not hard, does require some skill and a set of centering drills. Right. There's that part too. Easy on a "real" lathe, not easy on the specific CNC lathe I have (it has a simple tailstock and no chuck for drill bits). I do have access to a 12" x 36" manually-operated screw lathe that would be able to do all the steps, but I have to pay $15/hr to rent it (not terrible, but also not free and the tool time is much greater cost than the material cost). > Personally, I'd probably find a friend with a home machine shop and buy > him a suitable quantity of his beverage of choice to do the job. > machinists don't own a shop because they *hate* machining. Right. You want a couple, and it's no big deal. Some beer and company and conversation and a chance to show off the tools. A box of a bunch of the same thing though, that's work. -ethan
Re: DEC H9xx rack parts needed
On 09/16/2017 01:47 PM, Ethan Dicks via cctalk wrote: > This sort of project would be perfect on this wee lathe. The pins > would be trivial (just need to grind an HSS cutting bit with the > profile you described), and the bushings not much harder (ordinary bit > for the main diameters and the taper, then cutoff, then rechuck and > cut down the face to get down to final length). You'll still need to center-bore the hole through the thing, which, while not hard, does require some skill and a set of centering drills. Personally, I'd probably find a friend with a home machine shop and buy him a suitable quantity of his beverage of choice to do the job. Home machinists don't own a shop because they *hate* machining. --Chuck
Re: DEC H9xx rack parts needed
On Sat, Sep 16, 2017 at 4:16 PM, Paul Koning via cctalk wrote: does anyone have any spare "pivot bushings" for the DEC H9xx series cabinets (H950, H960, etc)? (These are the short pieces with a conical top which fit over the hinge pins, at the bottom.) >>> >>> http://ana-3.lcs.mit.edu/~jnc/tech/jpg/H9xxPinBushing.jpg >>> >> If you have a lathe, this looks like a very nice beginner's project. I was thinking much the same. I recently came into a 1990s vocational school CNC lathe (neighbor by my younger brother moved out and gave it to him on the way out), 3" x 6". Light Machines Corp made the control box and proprietary 8-bit ISA cards. This one came with an AT&T/Olivetti PC6300 that looks like it was an a car wreck (I needed a prybar to open the case). The disk was an ST251 on an 8-bit controller and, surprise, isn't readable. Worst case, if I can't resurrect the PC, I'll probably throw an Arduino on it and use modern Open Source tools for driving it (the LMC box has a DB25 with all the step and direction and endstop signals on it for Mach3 or Grbl or whatever). This sort of project would be perfect on this wee lathe. The pins would be trivial (just need to grind an HSS cutting bit with the profile you described), and the bushings not much harder (ordinary bit for the main diameters and the taper, then cutoff, then rechuck and cut down the face to get down to final length). -ethan
Re: DEC H9xx rack parts needed
> On Sep 16, 2017, at 4:10 PM, Paul Koning via cctalk > wrote: > > >> On Sep 16, 2017, at 9:52 AM, Noel Chiappa via cctalk >> wrote: >> >>> does anyone have any spare "pivot bushings" for the DEC H9xx series >>> cabinets (H950, H960, etc)? (These are the short pieces with a conical >>> top which fit over the hinge pins, at the bottom.) >>> ... >>> I could also use some more of the pins (particularly the kind with the >>> hole drilled through them to take a roll pin) >> >> Someone asked for an image of these; here: >> >> http://ana-3.lcs.mit.edu/~jnc/tech/jpg/H9xxPinBushing.jpg >> >> is one. The pin in the picture is the kind without the hole at one end, but >> they are otherwise identical. (Ignore the retaining ring on the pin; those >> are easy to get, my local hardware store has them.) > > If you have a lathe, this looks like a very nice beginner's project. Start > with a rod of the right diameter; a simple way to get such a rod is to buy a > long bolt, because those are mostly not threaded. Failing that, get a length > of "drill rod" from a metal supply outlet. Then all you need is to grind a > tool bit (high speed steel) to form a narrow screwdriver-like tip to cut > those grooves. Hold the rod in the lathe, cut the grooves in the right > spots, cut the thing to length, done. Ok, I read that wrong. You were talking about the short thing. Still, that's an easy project. Same idea. Start with a rod, grip in the chuck, drill, cut bevel, cut the two diameters, then cut to length. Elementary lathe operation books are easy to find; the South Bend Lathe manual that used to be reprinted by Lindsay Publications is very good. It's probably still available even though Lindsay unfortunately retired some years ago. paul
Re: DEC H9xx rack parts needed
> On Sep 16, 2017, at 9:52 AM, Noel Chiappa via cctalk > wrote: > >> does anyone have any spare "pivot bushings" for the DEC H9xx series >> cabinets (H950, H960, etc)? (These are the short pieces with a conical >> top which fit over the hinge pins, at the bottom.) >> ... >> I could also use some more of the pins (particularly the kind with the >> hole drilled through them to take a roll pin) > > Someone asked for an image of these; here: > > http://ana-3.lcs.mit.edu/~jnc/tech/jpg/H9xxPinBushing.jpg > > is one. The pin in the picture is the kind without the hole at one end, but > they are otherwise identical. (Ignore the retaining ring on the pin; those > are easy to get, my local hardware store has them.) If you have a lathe, this looks like a very nice beginner's project. Start with a rod of the right diameter; a simple way to get such a rod is to buy a long bolt, because those are mostly not threaded. Failing that, get a length of "drill rod" from a metal supply outlet. Then all you need is to grind a tool bit (high speed steel) to form a narrow screwdriver-like tip to cut those grooves. Hold the rod in the lathe, cut the grooves in the right spots, cut the thing to length, done. paul
RE: DEC H9xx rack parts needed
Van: Noel Chiappa via cctalk<mailto:cctalk@classiccmp.org> Verzonden: zaterdag 16 september 2017 15:52 Aan: cctalk@classiccmp.org<mailto:cctalk@classiccmp.org> CC: j...@mercury.lcs.mit.edu<mailto:j...@mercury.lcs.mit.edu> Onderwerp: Re: DEC H9xx rack parts needed > does anyone have any spare "pivot bushings" for the DEC H9xx series > cabinets (H950, H960, etc)? (These are the short pieces with a conical > top which fit over the hinge pins, at the bottom.) > ... > I could also use some more of the pins (particularly the kind with the > hole drilled through them to take a roll pin) Someone asked for an image of these; here: http://ana-3.lcs.mit.edu/~jnc/tech/jpg/H9xxPinBushing.jpg is one. The pin in the picture is the kind without the hole at one end, but they are otherwise identical. (Ignore the retaining ring on the pin; those are easy to get, my local hardware store has them.) Noel Got the pivot bushing here in front of me, it’s yours. I am pretty sure I have one or two pins *with* a hole at one end, but I remember they are not perfectly straight. You will have to hammer them a bit to straighten them. I will check whether I can find those two pins, and send them to you in a “bubble envelop” marked as “old metal pivot parts”. Greetz, Henk
Re: DEC H9xx rack parts needed
> does anyone have any spare "pivot bushings" for the DEC H9xx series > cabinets (H950, H960, etc)? (These are the short pieces with a conical > top which fit over the hinge pins, at the bottom.) > ... > I could also use some more of the pins (particularly the kind with the > hole drilled through them to take a roll pin) Someone asked for an image of these; here: http://ana-3.lcs.mit.edu/~jnc/tech/jpg/H9xxPinBushing.jpg is one. The pin in the picture is the kind without the hole at one end, but they are otherwise identical. (Ignore the retaining ring on the pin; those are easy to get, my local hardware store has them.) Noel
RE: DEC H9xx rack parts needed
Van: Noel Chiappa via cctalk<mailto:cctalk@classiccmp.org> Verzonden: zaterdag 16 september 2017 01:04 Aan: cctalk@classiccmp.org<mailto:cctalk@classiccmp.org> CC: j...@mercury.lcs.mit.edu<mailto:j...@mercury.lcs.mit.edu> Onderwerp: DEC H9xx rack parts needed Hi, does anyone have any spare "pivot bushings" for the DEC H9xx series cabinets (H950, H960, etc)? (These are the short pieces with a conical top which fit over the hinge pins, at the bottom.) I need at least one to hang a back door which I have. If nobody has any, they'd be easy to machine, so I might look into having a run made by some local machinists. (I do have a lathe, but have little lathe experience, so machining one of those myself is probably out of my range.) If it's someone with a CNC lathe/etc, I could probably get more made for little more than materials cost. If none turn up in response to this, I'll ask on the list about interest before I set off to find a machinist. I could also use some more of the pins (particularly the kind with the hole drilled through them to take a roll pin), if anyone has any of those spare. Thanks! Noel Hi Noel, I am going to my “museum” this afternoon, and will check. I am prety sure, I can help (and return a favor) 😊 Greetz, Henk
RE: DEC H9xx rack parts needed
or find some one with a brown and sharpe... screw machine... keep them employed! Sent from AOL Mobile Mail On Friday, September 15, 2017 Noel Chiappa via cctalk wrote: Hi, does anyone have any spare "pivot bushings" for the DEC H9xx series cabinets (H950, H960, etc)? (These are the short pieces with a conical top which fit over the hinge pins, at the bottom.) I need at least one to hang a back door which I have. If nobody has any, they'd be easy to machine, so I might look into having a run made by some local machinists. (I do have a lathe, but have little lathe experience, so machining one of those myself is probably out of my range.) If it's someone with a CNC lathe/etc, I could probably get more made for little more than materials cost. If none turn up in response to this, I'll ask on the list about interest before I set off to find a machinist. I could also use some more of the pins (particularly the kind with the hole drilled through them to take a roll pin), if anyone has any of those spare. Thanks! Noel
DEC H9xx rack parts needed
Hi, does anyone have any spare "pivot bushings" for the DEC H9xx series cabinets (H950, H960, etc)? (These are the short pieces with a conical top which fit over the hinge pins, at the bottom.) I need at least one to hang a back door which I have. If nobody has any, they'd be easy to machine, so I might look into having a run made by some local machinists. (I do have a lathe, but have little lathe experience, so machining one of those myself is probably out of my range.) If it's someone with a CNC lathe/etc, I could probably get more made for little more than materials cost. If none turn up in response to this, I'll ask on the list about interest before I set off to find a machinist. I could also use some more of the pins (particularly the kind with the hole drilled through them to take a roll pin), if anyone has any of those spare. Thanks! Noel