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Deep Hole .218 x 8"
taurokm3
Any one have any thoughts on the best way to go about a deep hole
without buying a deep hole rig? I am currently experimenting with a home made drill, .175 x 11" shank with a .218 x 1" head, and I want to mill it to a flat on top and bottom, then sharpen it like a twist drill. I know it will need cleared frequently, and a lot of lube. BTW, I am using oil hardening drill rod for the bit. Any one have any other ideas? |
Re: Ammeter
Marty N
Guys:
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HF Micro Mill motor, 1.8 amps 110 volts or 198 watts. Board is a 150 watt board current limit 1.4 amps, 76% Motor is billed as a 1/5th hp motor, 150 watts, that fits for full load current. Real output about advertised HF Mini Lathe motor 3.0 amps 110 volts 330 watts, 250 watt board, current limit 2.27 amps 76% Motor is billed as a 3/4 hp motor, 559 watts....yea? But not stalled or unregulated either, maybe ;( Real output closer to 1/3 hp. 559 watts at 110 volts would be about 5 amps (fuse) rating. Wilton Mini Wood Lathe motor, 2.3 amps 120 volts or 276 watts or about 3/8 hp, board unmarked but billed as a 2/5 hp motor or 298 watts, pretty close to theoretical input. As the other two motor/controller set ups seem to follow a rough 76% out put to input rule, sort of, kind of maybe...This motor is likely closer to 210 watts or about .281 hp. Advertised out put seems just a shade short of theoretical. Seems to be more ways to power factor a motor than there are manufactures (sales people). You should see the ratings some robot motor manufactures put out. Continuous power, power for 2 hours, 6 minutes, 30 seconds, momentary, stalled and on and on. Anybody got a scope and a motor dyno? ;-) Chris bills the F350 board as an "upgrade" to the small lathe motor which intuit suggest a 3.2 amp current limit as "extra capacity". Seems more in line with the motor name plate current anyway. Now I know why some fit tread mill motors to these things. If you can't get the truth then just Tim Allen the thing :) Marty ----- Original Message -----
From: Ed To: 7x12minilathe@... Sent: Sunday, April 08, 2007 9:26 PM Subject: [7x12minilathe] Re: Ammeter Thanks again, Ian. The motor is labeled DC120V, 3A, 400W. The wiring should be simple. The manual shows the #2 wire as + DC Out and it's a screw terminal. I'll order a meter (and a few other parts that have been on my list) and let you know later in the week how it goes. Ed |
Re: through bore
You'd actually be better off with a suitably large conventional
boring bar. A regular boring bar will ensure that the spindle bore is concentric with the axis of rotation. As a generality, the carriage is preferable to the TS for accurate, controllable tool holding. The virtue of the reamer is that it's quick & available for the cost of postage! Since the bore can be reamed, it's not a big enough cut to justify (to me) the nuisance of setting up a boring bar. Then again, I did mine a few years ago, when the community was smaller. Roy --- In 7x12minilathe@..., "andyf1108" <andyf1108@...> wrote: inside the spindle, then a length "B" of smaller diameter carrying thethe tailstock centre? |
Re: Not sure what to adjust...
In addition to setting the compound gib screws tight, position it so
it's full supported, use the cross slide to advance the tool. If you change to a "T" shaped parting tool, you'll get better results; they're markedly better than the other shapes. They also benefit from a little honing after grinding. If it's a really thin walled piece, you may have to cheat - mark the cut with the parting tool, take it out of the lathe & finish the cut with an abrasive wheel. Roy --- In 7x12minilathe@..., "NESTOR MONLLOR" <amaliomonllor@...> wrote: work, the cutter rides, I guess, downward then "pops" up. The bottom of the crosslide doesn't seem to be moving, but either the compound or the tool post does move. I checked and the toolpost seems to be tight to the compound. Which leads me to believe the compound is loose. Where do ZI tighten this? It turned into a major problem because I was making a ferrule for afly rod and the piece got all bent to heck and is now completely unusable. Thank you, |
Re: Ammeter
G'day Ed.
UNPLUG THE LATHE FROM THE POWER BEFORE WORKING ON THE CONTROL BOX! Putting the meter between the reversing switch and the motor means the current reverses and the meter needle will be against the stop when reversing, that's why I connected it between the board and the switch. Believe me, I'm not into hard work, just outcomes. Regarding the motor: Take the cover off (three screws at the back oh the lathe and look at the nameplate details. It will say 90V and then give a wattage eg 400W. This is the power of the lathe. The power figure (400W) divided by the voltage (90V) gives you the current at full load (flc). There are some losses, typically 10% for a motor of this size but they can be ignored for this exercise. Selecting a meter that can read to at least twice the flc, but not much more, will place the full load current at 40-50% of scale for a dc meter. This quite useable resolution. AC meters have a non linear scale at the low end and are even more critcal to get the right range. I used insulated male and female spade connector crimped to the wire such that the meter can be taken out of circuit and the normal connection rstored by connecting the respective spades. make sure you tape over the connections afterwards with a good quality electrical tape. The wire connects from the + terminal of the board to the centre terminal on the switch. I chose th cut the wire and put in the connectors but I could have just pulled the spade connector off the + terminal and with M & F terminals on the meter leads connected straight in. If your board has screw terminals it is even easier, you just need a floating screw connector (Blue Point or other) WHAT EVER YOU DO, UNPLUG THE LATHE FROM THE POWER BEFORE WORKING ON THE CONTROL BOX! UNPLUG THE LATHE FROM THE POWER BEFORE WORKING ON THE CONTROL BOX! UNPLUG THE LATHE FROM THE POWER BEFORE WORKING ON THE CONTROL BOX! UNPLUG THE LATHE FROM THE POWER BEFORE WORKING ON THE CONTROL BOX! One good turn deserves another. Regards, Ian --- In 7x12minilathe@..., "Ed" <edo@...> wrote: $12 each. I pulled my electronics and it looks like it'd be easy to adda meter to the DC side, especially if I can connect it between thethe + or - side?help me figure out what wire to use.just thinking the resolution of a 5A meter would be much better than a10A.
|
Re: Ammeter
Thanks, Ian, for the explanation. I get a catalog from
allectronics.com. They have AC and DC meters in various ranges for $12 each. I pulled my electronics and it looks like it'd be easy to add a meter to the DC side, especially if I can connect it between the direction switch and the motor. Does it matter if the meter is on the + or - side? If I have to put it between the board and the switch, it'll be more difficult, but there's a wiring diagram in the manual that should help me figure out what wire to use. I'm still a little confused on the amperage rating. Is the 400W for the lathe or the motor? The way I see it, if an appliance, i.e., the lathe is rated at 400W, then it'll only draw 3.3A regardless of what DC voltage is used. (And at 150% of that, a 5A meter would be OK.) That would mean that the motor in a '400W' lathe running at 90VDC would be rated at 300Watts (if we ignore the power used by the electronics.) Feel free to point out the flaws in my logic. I'm just thinking the resolution of a 5A meter would be much better than a 10A. Ed |
Re: Rotating Tailstock Chuck for my Cummins 5278 mini lathe
G'day Keith
"Did I leap before I looked when buying this brand???" From the other side of the world I'd say it depends on the colour! One good turn deserves another. Regards, Ian --- In 7x12minilathe@..., "John doe" <mrbigcox2000@...> wrote: I have gotten from you guys is great....What I am looking for is alathe are not the most helpful in the world....Did I leap before I looked |
Re: Not sure what to adjust...
G'day Ren.
I have looked at other's posts and what they say is true but may not have answered your problem. I read that you are seeing flexing of the compound and tool post structure. Having the gibs for the cross slide and compound firm is critical. Obviously you need to be able to move the cross slide so you can't lock up the gibs for that but you can make sure they are firm. For the compound you can set you tool at the right position and then tighten the gib screws so the compound doesn't move. I am assuming you have a saddle lock. If not you must stop the lead screw (gear in neutral) and engage the half nuts. This works if you use the carriage hand wheel to force the carrage back against the nuts taking out the slack. Make sure the tool has sufficient clearance and mount it a bee's whisker high so that flexing brings it to the right level. A FORGoTTEN FACTOR is flexing of the work piece. A fly rod ferule will be very thin and can deform under the tool load; you may be better off parting some other way or designing a thickened section with more strength to part through. I have to do this job myself sometime. My son borrowed one of my rods and jammed it in his car door so I need to make a new ferule; I have thought about it. Planning is half the job. One good turn deserves another. Regards, Ian --- In 7x12minilathe@..., "NESTOR MONLLOR" <amaliomonllor@...> wrote: work, the cutter rides, I guess, downward then "pops" up. The bottom of the crosslide doesn't seem to be moving, but either the compound or the tool post does move. I checked and the toolpost seems to be tight to the compound. Which leads me to believe the compound is loose. Where do ZI tighten this? It turned into a major problem because I was making a ferrule for afly rod and the piece got all bent to heck and is now completely unusable. Thank you, |
Re: Thanks...
Jeff Demand
John,
Still in the trade with 30+ years and counting, high end diamond custom to fashion on the resume. I was presented with the possibility of self employment 7 years ago when my last employer sold the company (but not me ;-) I had been doing some simple cad cam milling for models and decided to try what I then referred to as 'self unemployment'. Rough road, as all start ups are but it's paid off. Some older work on the site in my sig. Current work is usually for licensed products and I can't release... bad enough having to deal with the client, now I have to satisfy the licensing companies legal beagles. Can't ever get away from the commercial concerns but at least I only answer to myself now. Jeff - Demand Designs Analog/Digital Modelling & Goldsmithing jdemand@... - * REPLY SEPARATOR * On 4/8/2007 at 6:49 PM John doe wrote: I just wanted to say thanks for all the fast knowledgeable, responses10:57 PM |
Re: Not sure what to adjust...
Are you using a QCTP? If so, be sure it's locked down tight. If not, the tools will flex slightly, and they tend to flex down, in reaction to the turning workpiece.
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----- Original Message -----
From: Nestor A. To: 7x12minilathe@... Sent: Sunday, April 08, 2007 10:23 AM Subject: [7x12minilathe] Re: Not sure what to adjust... I just checked the tool height and it is dead on center. Ren |
Re: Ammeter
G'day Ed.
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I respect your wish to "stay away" from the motor wiring" but is no bigger issue than wiring into the ac side. I used a dc meter because that was available directly from an electronics retailer. I know ac instruments are available through the electrical trade houses, I specify then in switchboards. The manual for my control board expects that a dc meter will be used when setting up the drive but allows for using an ac meter by giving a compensation factor. If the meter is connected in the ac circuit the manual says set the ac current a 75% of motor flc, whereas for dc it is set to 150%. (As an experienced electrical engineer I am am uncertain of what their wording means, is the ac to dc meter conversion factor 0.75 or .5? Its too early in the morning to dig out my text books)). You may have noted from the above that the motor stall current is set 150% of full load current. The stall current can be up to 2 times but this must not be exceeded. KB electronics advised me that a 1.7 factor should be used. I have a 180V 400W motor with a full load current of 2.2 amps, my stall current setting will be 3.5 amps; thus I need a 0-5 amp meter. If you motor is 90 volts you will need a 0-10 amp meter. For 120Vac your motor will be a 90V unit with flc of 4.4 amps and could have a stall current of 7 amps. You conrol board may not be able to deliver this current. Jim Rabid may be able to advise you of what your board can do. As for fuse blowing, this should NEVER happen if the right size fuse is installed AND the motor is not left on stall; when it stalls you switch it off! Please note that fusss are a thermal device. They do not trip the instant the current through them exceeds their rating, this is a common misconception. The heating energy which melts the element is proportional to the square of the current multiplied by the time, higher currents require less time to melt the element. At the rated current the heating energy matches the heat the element can discipate to its surroundings so it never gets hot enough to melt. In their overload range circuit breakers have similar characteristics. Hope this helps One good gturn deserves another. Regards, Ian --- In 7x12minilathe@..., "Ed" <edo@...> wrote:
|
Re: Not sure what to adjust...
Have you got the compound set at 90 degrees? I find it works much
better if it's set 75 or more degrees. Normally I leave it at 60 (30 off 90) where one point on the dial equals 0.0005 inches in. That is, if you turn it forward 1 point, it'll remove 1 thousandths of the diameter of the workpiece you're turning. |
Re: Not sure what to adjust...
shafwood
Two more thoughts: Be sure the parting tool is set so the least
possible length (to do the job) extends out of the toolholder. If you were trying to part off brass, you must have zero to negative rake on the top edge of the parting tool (in other words completely opposite from parting steel). Jim |
Re: Thanks...
<<<"John doe" writes:
Does anyone ever showcase what they do?.... >>> Try NAMES in Toledo, Ohio, in a couple weeks or Cabin Fever in January in Pennsylvania. There are other model engineering shows on the west coast. There is lots to see and buy. Plus, you can meet some of the people from the list. Bill Moll NW Georgia (and far from all the shows) *** See what's free at . |
Re: Not sure what to adjust...
Two other thoughts: Make sure that the parting tool itself is set in the toolholder at a 90 degree to the axis of the lathe. Try to locate the parting tool as close as possible to the rotating chuck.
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Gregor Stransky, San Antonio, Texas ----- Original Message -----
From: "John" <John@...> To: <7x12minilathe@...> Sent: Sunday, April 08, 2007 1:09 PM Subject: [7x12minilathe] Re: Not sure what to adjust... Hi Ren, Is the tool point over the cross slide or is the compound advanced such that the tool point is left of the cross slide dovetail - this can cause "rocking" of the dovetail which may be what you're experiencing. What material are you parting, what is the diameter, is it hollow, and how far is the parting tool from the chuck when you have this problem? How wide is the parting tool and does it have top rake? Are you making a few pieces or will you be making many ferrules? A simple fixture might be worth trying if you're doing many of these. John --- In 7x12minilathe@..., "NESTOR MONLLOR" <amaliomonllor@...> wrote: the cutter rides, I guess, downward then "pops" up. The bottom of the crosslide doesn't seem to be moving, but either the compound or the tool post does move. I checked and the toolpost seems to be tight to the compound. Which leads me to believe the compound is loose. Where do ZI tighten this? It turned into a major problem because I was making a ferrule for afly rod and the piece got all bent to heck and is now completely unusable. Thank you, |
Thanks...
I just wanted to say thanks for all the fast knowledgeable, responses
and all the info that this group has supplied me.... They say the Internet is an endless highway of info.... The key word is endless...Always seeking and never finding.... But then I found you guys and can now exit the highway and relax with a cup of Joe.... Does anyone ever showcase what they do?.... Hobbyist???...Artist???...Machinist???.... Or maybe all of the above???..... I myself have a family (now retired) that was in the gem and jewelry biz for over 35 years.....Never sold anyone else's works, total custom...I always wanted the uniquely different so that's where the carving came in....TOI (Tools Of Impalement...knives) was the road I traveled for awhile along side body jewelry.... Cut and carved with blood, sweat, and tears.... To keep up with more modern ways, and a son (quality time, big bonus) that fell in love with the lathe at school, hence the cummins lathe...Not to mention that these hands are old and don't work as well anymore.... LOL.... Now I am able to go on with what I love with more definition and sharper lines....Sorry for all of the babbling, just wanted to say thank you!!!! |
Re: Ammeter/Parting
Marty N
Hi Marty,
The round shank is an interesting feature - they went to some trouble to grind that since they started with a square blank. My guess is that this is a threading tool rather than a cutoff tool; the round shank allows angling the tool as is needed when making square threads. <snip> John Pretty sure its parting John. This tip can be held at any angle you please and this wouldn't cut a tread of any form I know of. Included angle across the face looking from above can't be more than 3 or 4 degrees and that only because of the relief angle I'd guess. Marty |
Re: I snapped a Carriage Retainer
Marty N
Thanks Paul
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I just can't cover every possible browser (setting) out there so this kind of info is helpful. Marty ----- Original Message -----
From: Paul Moir To: 7x12minilathe@... Sent: Sunday, April 08, 2007 12:04 PM Subject: [7x12minilathe] Re: I snapped a Carriage Retainer > > Bill: > > I checked the site and it came up fine?!?!? I reloaded it anyway, try again. > This has happened once before as was corrected in this way. Sorry for the > trouble. If it still does it try the refresh button once on the site. > > Marty > Try it with a Gecko based browser like Firefox, Netscape 6.0+, Seamonkey, Konqueror, etc. Validator.w3.org mentions a few errors that may help you find the trouble. I get the same problem with both Firefox and Konqueror. It works normally in IE. I'm running Linux at 1600x1200 desktop resolution. |
Re: Not sure what to adjust...
Hi Ren,
Is the tool point over the cross slide or is the compound advanced such that the tool point is left of the cross slide dovetail - this can cause "rocking" of the dovetail which may be what you're experiencing. What material are you parting, what is the diameter, is it hollow, and how far is the parting tool from the chuck when you have this problem? How wide is the parting tool and does it have top rake? Are you making a few pieces or will you be making many ferrules? A simple fixture might be worth trying if you're doing many of these. John --- In 7x12minilathe@..., "NESTOR MONLLOR" <amaliomonllor@...> wrote: the cutter rides, I guess, downward then "pops" up. The bottom of the crosslide doesn't seem to be moving, but either the compound or the tool post does move. I checked and the toolpost seems to be tight to the compound. Which leads me to believe the compound is loose. Where do ZI tighten this? It turned into a major problem because I was making a ferrule for afly rod and the piece got all bent to heck and is now completely unusable. Thank you, |
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