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Re: Tips on machining pulley grooves
Thanks both, good advice and sounds like a mix of steps would be the way forward. Roughing out, followed by left / right cuts before a final, slightly deeper forming cut.
I appreciate that the U3 probably isn’t quite up to the task. ?I’m making the motor pulley first and am hoping I can use the more powerful DC motor to make the other two. (Night here in the UK now, more tomorrow no doubt). |
Re: U3 carriage ‘yawing’
Hello:
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On Sat, Sep 16, 2023 at 05:48 PM, Charles Daldry wrote:
... same problem with my Emco Compact 5 ...Ahh ... I see a pattern becomes visible. Not only Unimat 3s. ... brass I made did not eliminate the play in the carriage, so I filed about about .004" from the part of the gib ...Yes, that's one way to do it albeit with a huge disadvantage: any further adjustments will always require partly dressing the brass gibs. Dressing the gibs' mating surfaces to the level where they should be is a permanent solution. And if and when further adjustment is needed you just turn over the gibs, evenly dress the whole side evenly or make new set. ... need to acquire the skill first.Same thing I said till I decided to jump in and be done with it. Just have to remember that Prudence, Patience and Constance will be your best friends while at it.? Best, JHM |
Re: Mensuration, was Re: [Unimat] What is the 'BEST' Unimat ?
开云体育[Even more off topic] My recollection of loading from a cassette is that it often took several
attempts, and even when successful, the programmes (using the archaic British spelling) did
very little of any practical value.
Bruce
On 14 Sep 2023 at 17:43, Andrei wrote:
>
> Damn, Bill. we had similar computers.
>
> My first PC was the Sinclair Z80, some 43 years ago. Has a whole 16kb
> of memory and had to load programs from a cassette tape.?
>
> https://en.wikipedia.org/wiki/ZX80
>
>
>
> ZX80 - Wikipedia
>
> en.wikipedia.org
>
>
>
>
>
>
>
>
>
> From: [email protected] <[email protected]> on behalf of Bill in OKC too
> via groups.io <wmrmeyers@...> Sent: Thursday,
> September 14, 2023 1:38 PM To: [email protected] <[email protected]>
> Subject: Mensuration, was Re: [Unimat] What is the 'BEST' Unimat ? ?
> Nope. Half an inch is 12.7mm. That two tenths of a millimeter is
> important! Sometimes! ;) I can use either system, but I'm
> math-challenged despite decades of study, so I use a calculator
> regardless. And the only time I needed to deal with 1/128" was back
> when I got my first Vernier caliper. What I hate is things that mix
> the two systems. Chevrolet vehicles, for example. BASTARDS! :) Had to
> change out the starter on my mini-van this week. Most everything on it
> is metric except the starter bolts.?
>
> Once upon a time, digital calculators were expensive. My first was a
> TI SR-51-II, and I paid $100 for it. That was about a third of my
> monthly paycheck then. When my teaching career ended, a bit over a
> decade ago, I could get a MUCH more powerful calculator for $1, with
> more scientific functions. And the TI-86 graphing calculator was going
> for about $100, then. It used a processor based on the Z-80 chip that
> ran my first appliance computer, the TRS-80 Model 1, and had the same
> graphics capability. Unlike the TRS-80, the TI-86 fit in the palm of
> my hand. Now I have a cheap Android phone, a MOTO G7 Supra. It has
> 32gigabytes of storage, and 2gigabytes of program memory. MUCH better
> graphics capability, too. I have a .5tb or 500gb micro-usb card in it
> for additional storage. And a scientific calculator app that will
> about everything BUT graphing. Including all the normal conversions.
> And another app that will display dwg files.?
>
> THERE IS NO EXCUSE FOR SUCH LACK OF PRECISION!? ;)
>
> Going through a set of drawings and trying to convert every dimension
> would be tough, though. Which means we need a means of converting on
> the fly. Digital calipers, anyone? ;)?
>
> Actually, I'll bet that if there is a method that can be used, someone
> is using it. I actually prefer to use the Imperial system, as modified
> in the USA, but can get along fine in Metric. Lived for a tad over 5
> years in Germany, and 3 in Turkey. I have bought gasoline in litres,
> and assorted foods in kilograms & grams, so I can get by.?
>
> Bill in OKC
> ?
> William R. Meyers, MSgt, USAF(Ret.)
>
> Aphorisms to live by:
> Good judgement comes from experience. Experience comes from bad
> judgement.?
> SEMPER GUMBY!
> Improvise, Adapt, and Overcome. Physics doesn't care about your
> schedule. The only reason I know anything is because I've done it
> wrong enough times to START to know better. Expect in one hand,
> expectorate in the other. See which one gets full first.
>
>
>
> On Thursday, September 14, 2023 at 09:14:11 AM CDT, Andrei
> <calciu1@...> wrote:
>
>
> I was too lazy to calculate so i just threw in the closest numbers:
> 9/16 is greater than half inch. Half inch is 12.5mm so the conclusion
> was that it is bigger than those two numbers the lazy way out Andrei
>
??
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Re: Tips on machining pulley grooves
All of what you say can be improvements.? The root problem is a lot of cutting surface all at once on a large diameter in a small minimally powered machine. Going in at two different X positions as you mentioned will help to mitigate this.? And, also, to an extent the chip formations from the left and right sides of the tool will, to some extent, both try to move into the same airspace above the tool bit.? They effectively collide there making things worse.? (The is the reason why single point thread cutting is ideally done at a 29 of 29.5 degree angle so most cutting is only on one edge.? Because for thread cutting this collision of the "left" and "right" chip can be severe.) You also mentioned what accounts to first roughing the shape.? This can be done with a narrow square end tool (such as a cut off tool because it takes a lot of grinding to make a narrow tool from a standard size tool bit) to make a number of cuts resulting in a stair step shape to approximate the final.? You still have the issue of a large diameter in a too small machine.? But will have the advantage of having a much smaller cross section of the cut.? Then finish with the forming tool.? Or it might even be possible to use a round file that is, or has a region that is, the correct diameter. Beyond that, it is important to have really sharp tool bits, a slow speed, and a lot of patience.? A cutting fluid for aluminum might help.? But with minimal removal rates, it might not make much difference.? And you probably aren't going to be able to get the part so hot that you have to worry about tool bit temperature.? But you never now. This is also an example where just because something fits the envelope of a machine, it is not necessarily comfortably within the machine's capability.? There are parts that might need a large swing to clear, but a small diameter is actually being worked on such as boring a hole or machining a smaller diameter feature.? That's different. Sometimes the easiest solution is to use a larger machine to make the part.? And if you don't have one, find somebody who does. Charles E. "Chuck" Kinzer
On Saturday, September 16, 2023 at 01:12:27 PM PDT, Peter Brooks <peter@...> wrote:
As part of my 24v re-motoring exercise I’m making new pulleys from aluminium. I’m not finding it easy to machine the groove for the belt and would appreciate any tips (apart from ‘buy them online’ and ‘do it on a bigger lathe’ - I just have the U3).
|
Re: U3 carriage ‘yawing’
开云体育I had the same problem with my Emco Compact 5, an overgrown U3.? I found that the brass I made did not eliminate the play in the carriage, so I filed about about .004" from the part of the gib that contacted the carriage. That raised the gib enough to eliminate the majority of the play.? I should probably finish the job by marking and scraping the gib to fit better, but I need to acquire the skill first. Charles Daldry On 9/16/23 13:28, Julius Henry Marx
wrote:
Hello: |
Re: Tips on machining pulley grooves
Use a hacksaw blade to remove some of the material before you use your tool, and that might help. Might also be "Interesting" trying to get just the right depth... ;) perhaps used a hacksaw blade, or piece of hacksaw blade, as a parting tool before cutting to depth with your profile cutter.? Bill in OKC William R. Meyers, MSgt, USAF(Ret.) Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY! Physics doesn't care about your schedule. The only reason I know anything is because I've done it wrong enough times to START to know better. Expect in one hand, expectorate in the other. See which one gets full first.
On Saturday, September 16, 2023 at 03:12:26 PM CDT, Peter Brooks <peter@...> wrote:
As part of my 24v re-motoring exercise I’m making new pulleys from aluminium. I’m not finding it easy to machine the groove for the belt and would appreciate any tips (apart from ‘buy them online’ and ‘do it on a bigger lathe’ - I just have the U3).
|
Tips on machining pulley grooves
As part of my 24v re-motoring exercise I’m making new pulleys from aluminium. I’m not finding it easy to machine the groove for the belt and would appreciate any tips (apart from ‘buy them online’ and ‘do it on a bigger lathe’ - I just have the U3).
|
Re: U3 carriage ‘yawing’
Hello:
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On Sat, Sep 16, 2023 at 03:42 PM, Peter Brooks wrote:
You're welcome, hope it was at least it gave you an idea as to where you stand. Make no mistake: everyone who comes across the problem notices it as it is a nightmare to try to turn even a small part properly. What was hard/impossible to find was the actual cause. Easily traced to the lack of QC + bad design decisions at Emco. But I digress. Like I mentioned, I searched all over the web for months looking to find references/solutions/modifications/etc. which would address the problem to no avail. While searching for a solution to making a new set of gibs, a member of that forum revealed the origin of the problem. The problem is actually twofold in origin: on one hand the plastic glass filled gibs (a contentious issue) and on the other the excess material present on the mating surface where the gibs sit. The new set of brass gibs was a start and the iterative process of dressing/adjusting their mating surfaces to get the right height made a world of difference. I was, as you can imagine, scared shitless (cue Stephen Stills/Woostock/1969) but reasoning it out in detail it quickly became clear to me that, even with a new set of gibs, if they did not run at the right height with respect to the guide rails there was no way I was ever going to be able to get it working properly. ie: the carriage would always have vertical movement. As the U3 carriage is made of Zamak, it has very little mass and the only way to keep it in place/down is via a properly adjusted set of gibs.? Best, JHM |
Re: U3 carriage ‘yawing’
Hello JHM, thanks for that and for the link to the post on ME. I’m glad I’m not the only one to notice the issue.
I did find some burring at the bolt holes and a bit of dressing with a hand countersink has helped a little I think. I’m still going to make more of a gib type arrangement (when I get round to it :-) with oilon replacement strips of the same dimensions as the originals, and brass strips above them threaded to take grub screws to apply pressure to the oilon ones below. I’m keen to use a non-destructive solution, and certainly wouldn’t be filing the saddle. My ham-fisted incompetence could make things considerably worse ! Cheers, Peter |
Re: Dial Calipers
I have a rolling tool cart from HF, and bought belts for the Unimat there, but otherwise do my best to avoid; they require a drivers license to return something, and I'm don't steal inventory from stores.? They are not getting my Drivers License and scanning it, it won't take long, and they will get hacked, like everyone else, (Banks, Hospitals, Governments, Insurance Companies, etc, etc.)
HF does have the third hands there and I have purchased for gifts for friends though and they are less expensive at HF then buying at Micromark. I bought a pair very similar to DIKAKO digital Calipers from Amazon, perhaps 6-7 years ago?? ? I think mine say AIKER on them, but they look like the exact same pair; mine takes a single battery and it easily unscrews with an included screw driver, the battery is the same one as my car remote starter / key fob.? I just replaced the battery yesterday. Tamra |
Re: Off Topic measuring units
开云体育Hello Dick: I invite you and all the Unimat folks to visit my shop and railroad. I really enjoy sharing. Carl. Here is the railroad and a glimpse of the shop: Charleston, South Carolina, USA On 9/16/2023 8:55 AM, OldToolmaker via
groups.io wrote:
Hello Carl, |
Re: Off Topic measuring units
The core imperial / standard units really are not that weird. Sure not as neat and tidy as metric with its base 10, but really not hard to work with.
Most of the really out there units are very industry specific, hogsheads, bushels, ffurlongs etc, and they are only weird out of context. If you were a 19th century winemaker then Horseheads would seem perfectly reasonable. Metric is less flexible resulting in its own need to adapt non-metric units in specific cases such as the French system for medical catheters or gauge system for needles. Don't even get me started on Celsius which in no way follows the rule of 10 of the metric system and is just as arbitrary as ferenheit only using other numbers. |
Re: Off Topic measuring units
I have a Mitutoyo dial caliper. School threw it out because someone left it in one of the CNC machines, and it froze.? I hosed it down with WD-40, let it sit for a week or so, with periodic dowsing in more WD-40. When I could get it to move again, I ran strips of paper under the head. Pulled out a bunch of rust. Resprayed, and repeated until no more rust was coming out on the paper. It is the most accurate and easiest to use of all my calipers. I did have to spend something like $7 to buy a new dial lock for it. :) Bill in OKC William R. Meyers, MSgt, USAF(Ret.) Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY! Physics doesn't care about your schedule. The only reason I know anything is because I've done it wrong enough times to START to know better. Expect in one hand, expectorate in the other. See which one gets full first.
On Saturday, September 16, 2023 at 08:25:36 AM CDT, Andrei <calciu1@...> wrote:
Calipers and micrometers are a dime a dozen. I have both metric and imperial. They are either dial or digital mechanical (no screwing around with batteries). I also have some conventional but seldom use them anymore.
I do have one of each in electronic digital. One is Starrett and one Mitutoyo and I got them second hand for less than 50 bucks each.
Don't let the perceived cost put you off. Calipers and micrometers do not hold value and can be sourced cheaply.
Get From: [email protected] <[email protected]> on behalf of OldToolmaker via groups.io <old_toolmaker@...>
Sent: Saturday, September 16, 2023 9:06:27 AM To: Carl <carl.blum@...>; [email protected] <[email protected]> Subject: Re: [Unimat] Off Topic measuring units ?
Hello Carl,
The only metric measuring tools ?I have are my 2 digital calipers. All my other measuring tools (micrometers etc are imperial. At 75 years old I am not about to invest in new tools for hobby use. Manual conversion is quick. Dick -- http://www.homemadetools.net/ forum/?OFF- SET-tailstock-center-65965#post105972 ?SMALL TURRET TOOL POST PLANS? ?LARGE TURRET TOOL POST PLANS ?MINI- LATHE CARRIAGE LOCK PLANS ?SMALL QC TOOL POST PLANS? ?QUICK CHANGE LATHE TURRET ?MINI LATHE COMPOUND PIVOT MODIFICATION |
Re: Off Topic measuring units
Andrei
开云体育Calipers and micrometers are a dime a dozen. I have both metric and imperial. They are either dial or digital mechanical (no screwing around with batteries). I also have some conventional but seldom use them anymore.
I do have one of each in electronic digital. One is Starrett and one Mitutoyo and I got them second hand for less than 50 bucks each.
Don't let the perceived cost put you off. Calipers and micrometers do not hold value and can be sourced cheaply.
Get From: [email protected] <[email protected]> on behalf of OldToolmaker via groups.io <old_toolmaker@...>
Sent: Saturday, September 16, 2023 9:06:27 AM To: Carl <carl.blum@...>; [email protected] <[email protected]> Subject: Re: [Unimat] Off Topic measuring units ?
Hello Carl,
The only metric measuring tools ?I have are my 2 digital calipers. All my other measuring tools (micrometers etc are imperial. At 75 years old I am not about to invest in new tools for hobby use. Manual conversion is quick. Dick -- http://www.homemadetools.net/ ?SMALL TURRET TOOL POST PLANS? ?LARGE TURRET TOOL POST PLANS ?MINI- ?SMALL QC TOOL POST PLANS? ?QUICK CHANGE LATHE TURRET ?MINI LATHE COMPOUND PIVOT MODIFICATION |
Re: Off Topic measuring units
Hello Carl,
The only metric measuring tools ?I have are my 2 digital calipers. All my other measuring tools (micrometers etc are imperial. At 75 years old I am not about to invest in new tools for hobby use. Manual conversion is quick. Dick -- http://www.homemadetools.net/ ?SMALL TURRET TOOL POST PLANS? ?LARGE TURRET TOOL POST PLANS ?MINI- ?SMALL QC TOOL POST PLANS? ?QUICK CHANGE LATHE TURRET ?MINI LATHE COMPOUND PIVOT MODIFICATION |
Re: Off Topic measuring units
Hello Carl,
I agree and that is how I operate in my home shop today. I am completely happy with that. Dick -- http://www.homemadetools.net/ ?SMALL TURRET TOOL POST PLANS? ?LARGE TURRET TOOL POST PLANS ?MINI- ?SMALL QC TOOL POST PLANS? ?QUICK CHANGE LATHE TURRET ?MINI LATHE COMPOUND PIVOT MODIFICATION |
Re: Dial Calipers
“ I generally have a pair on our Dining Room table so I can measure something quickly.”.
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“No pudding until you eat up all your greens!” “Half?, please”, “ok half”. “Can I have pudding now?” “That’s not half!” “Yes it is!” On 16 Sep 2023, at 04:09, Tamra <tamrabrogdon@...> wrote: |
Re: What is the 'BEST' Unimat ?
开云体育You’re welcome Pat.? As a science major I got used to the metric system in high school (early 1960s) as almost every class I had drilled us on using the metric system and doing conversions.? As calculators were rare (and expensive), they were not allowed in class so everything had to be done on a slide rule.? When students complained, one of my teachers used to tell them, “Come on now.? It’s as easy a falling off a log.”? Most in the class never got the pun. ? When I was a grad student in radiological sciences (which was health physics and some medical physics) I missed my chance to take the reactor operator class (we had a small Triga reactor in the basement of the physics building) .? Instead, the department chair dropped me and another student into the first two quarters of medical school, which likely did me more good as a health physicist..? ?? ? Jerry F. ?? ? From: [email protected] [mailto:[email protected]] On Behalf Of pat goodyear
Sent: Friday, September 15, 2023 10:49 AM To: Gerald Feldman; [email protected] Subject: Re: [Unimat] What is the 'BEST' Unimat ? ? Jerry; you popped a memory bubble.? ?Back in Naval Nuclear Power School (1974) in order to grasp unit conversions, we had all sorts of goofy conversions to do.? One was to convert furlongs per fortnight to inches per second, to mm per second .....? ?As? some of our calculations dealing with forces inside a reactor at power could be mind numbing.? ? Anyhow thanks for the blast from the past.? ? |
Re: Dial Calipers
My only digital caliper is a Harbor Freight unit that I've been fighting with for about 6 years.? It would reset to zero randomly due to bad battery connections.? I finally figured out how to make it reliable, and it's actually not that bad.? I do like using it convert units, sort drill bits, etc.? (I also have 5 or 6 "real" dial calipers like B&S, Tesa, etc, but my goto is an Enco I got in '86 that gets abused, but has never failed me) -Dave
On Friday, September 15, 2023 at 08:09:34 PM PDT, Tamra <tamrabrogdon@...> wrote:
I truly appreciate Dial Calipers... When I attend classes, I take a pair of dial calipers and the digital dial calipers that convert to mm at touch of a button, they are truly useful, and I generally have a pair on our Dining Room table so I can measure something quickly. In terms of doing projects on a metal lathe, I think it is very, very useful to have 2 pairs.? One pair measures the diameter, and 1 pair measures the length... this has been very helpful when I'm making duplicate parts.?? Tamra |