Ordinarily when I need to setup an accurate taper on the lathe I install a test bar and use an indicator and the rise over run method to bump in the compound. Sometimes that's way over kill. Plus or minus a degree is good enough. Okay half degree if single point threading, but still... Sometimes the protractor on the cross slide below the compound is plenty good enough.
A few weeks ago I was hacking out something, and I went to set the angle only to find all the markings were gone. There was a nice aluminum insert glued into a slot on the cross slide, but instead of being engraved it was printed. When I wiped the gook off so I could read there weren't any. I eyeballed it with a hand held angle gage and finished my part, but I had to go get that angle gage. Its a tool I keep in my desk. Not one I keep at the lathe.
In between other things i pulled the compound, measured up the various radii, and laid out a new scale.
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There is 2-3 degrees of adjustment in the slot. I probably should have made the screw slots shorter. Who knows. I might not even put screws in. I might just glue it in place with something a little stronger than the rubber gook that help in the old one.
Very nice, I wonder if you could add a vernier scale to the other part to aid accurate set-up in the future. I've done similar on a bender I made using a rotary table and a single point lathe tool held in the quill on my BP, for getting the numbers accurately aligned I used the DRO for the offsets and made a guide for my number stamps so the digits were where I wanted them and the results were really good, a mate asked if it was a bought tool. That guide I've mentioned before IIRC as one end was held by a collet and another rod went into the hole at the side of the BP quill housing so the guide was fixed.
The digits were done one at a time as the guide was intended for a single punch and the position changed for the next digit so I could get the digits centred around the line. I have subsequently acquired a set of Prior alphanumeric punches intended for making up multi letter/digit combinations as the punch widths vary with the letter/digit width so next time I do to do that sort of operation I'll use those.
The digits were done one at a time as the guide was intended for a single punch and the position changed for the next digit so I could get the digits centred around the line. I have subsequently acquired a set of Prior alphanumeric punches intended for making up multi letter/digit combinations as the punch widths vary with the letter/digit width so next time I do to do that sort of operation I'll use those.
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My Enco punches worked well enough on flat sheet stainless to make tags giving the working load of chain, but often the workpiece is rounded such as a dial and aligning the bottoms against a thin strip still leaves the text wobbly and unevenly spaced. I'm not skilled enough to engrave neatly, maybe I should practice.
Yep. CNC. I created the whole part in my CAM (not CAD) software which has decent 2D CAD capabilities. I used the XY plane origin for reference as an easy arc center for everything. When the Y coordinate was about right for the text, I aligned to center on the Y axis. Then it was a matter of copy, paste, change text, align, rotate ten degrees.
50 and 60 were moved a few degrees to leave more room for the screw slots. All of the markings were laid out much the same way, except I used a polar array copy function.
There are a couple videos on making letter number punch guides, but the basic concept is not dissimilar to a drill guide block or tap guide block. I am 100% certain you can make something adequate in an afternoon if you want to. I don't think that is all of the problem people experience though. As you noted a curved surface can be an issue, but if you made a guide with enough thickness to hold the punch straight up well enough, at the least your lettering would be uniformly stamped from one to the next even if it will be non uniform on an individual basis due to the curved work piece material. Often I think people actually do a fair job of positioning, but because its a non uniform width font on your standard block letter punch sets it looks off even when it is not. This is where CAD/CAM and CNC can shine. You can center your markings regardless of the size of the individual characters. Of course you can also map a curved surface, or if drag engraving use a spring loaded engraver.
Yep. CNC. I created the whole part in my CAM (not CAD) software which has decent 2D CAD capabilities. I used the XY plane origin for reference as an easy arc center for everything. When the Y coordinate was about right for the text, I aligned to center on the Y axis. Then it was a matter of copy, paste, change text, align, rotate ten degrees.
50 and 60 were moved a few degrees to leave more room for the screw slots. All of the markings were laid out much the same way, except I used a polar array copy function.
Bob La Londe
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I spent nearly a decade using CAD to design circuit boards and their milled RF-tight housings so I understand the concepts. I can't justify CNC for hobby use since most of what I do is cut-and-try fitting to existing parts, for example fabricating a new heat shield for a catalytic converter. I do draw new parts such as the gantry track splice with a trial version of the PCB program, whose line drawing functions cover every shape I can manually machine, or in that 16 foot long instance lay out, center punch and drill in the driveway.
The flange at the rear of my 2000 CRV's original catcon rusted away enough to loosen the joint to the muffler pipe, which then rattled although I couldn't detect the play, only the metallic clank when I hit that area with my hand. Suspecting internal breakage I bought and installed a new catcon and oxygen sensor, then saw that nothing was loose inside the original, although the flange holes had reduced to less than half circles and were barely holding the bolt heads. Originally they were studs, lost long ago to road salt. I suppose that at 80,000 miles it didn't owe me anything and may be partly clogged.
The new Magnaflow catcon didn't have a heat shield while the OEM one did. The apparently knowledgeable parts clerk said rotted-off heat shields haven't caused problems and many come without them. At idle after a trip my thermal imager shows 185F on the catcon body, and a max of 626F upstream of it where there never was a shield. I previously made a stainless louvered heat shield for the original which wasn't an ideal fit though it's better on the Magnaflow.
Do y'all think I should install the shield or only the top half if one wasn't provided?
Maybe you just can't justify those high dollar machines you were spoiled on in industry... I can do pretty good work with a lot less machine than that, and some of those old industrial machines weren't really as good as some people's memories of them are.
since most of what I do is cut-and-try fitting to > Do y'all think I should install the shield or only the top half if one
The floor of the vehicle cabin is an amazing heat shield, but getting it hot makes it more reactive chemically. You decide. Maybe think of an actual heat shield as a sacrificial anode.
Maybe you just can't justify those high dollar machines you were spoiled on in industry... I can do pretty good work with a lot less machine than that, and some of those old industrial machines weren't really as good as some people's memories of them are.
since most of what I do is cut-and-try fitting to > Do y'all think I should install the shield or only the top half if one
The floor of the vehicle cabin is an amazing heat shield, but getting it hot makes it more reactive chemically. You decide. Maybe think of an actual heat shield as a sacrificial anode.
--------------------- "Maybe you just can't justify those high dollar machines you were spoiled on in industry"
I wasn't exactly spoiled by a ProtoTRAK Bridgeport that I used mostly in jog mode, since the Segway chassis castings I was modifying or imitating weren't all that well specified on the print, some features were "see the pattern", notably the tapered battery pack locating posts. I got the jobs that needed old-fashioned scribe and punch layout experience.
At Mitre I designed parts to be milled on a Hurco though I never was allowed to run it. My only formal CNC training was writing G code for the Emco Compact 5 lathe.
"some of those old industrial machines weren't really as good as some people's memories of them are."
What do you think I'm using now? Instead of a '65 Mustang my Old American Iron is a '65 South Bend Heavy 10, much more use to me.
The conflicting consideration for the catcon is if it might run hotter than designed with airflow restricted. If I start smelling hot plastic I can stuff a thermocouple under the carpet to monitor the temperature. Since retirement I've timed my errands to avoid traffic jams.
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