Making Lather Profile tools?

Metric system, car pool lanes on the freeway, lite beer, and instant coffee. Time to declare these experiments a failure and move on.

Reply to
Roger Shoaf
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Last american vehicle was a '90 Lumina APV. In Feb. '97 I needed the spare "donut" and when I tried to lower it on it's cable winch, it fell to the pavement (at least I still had it) - the end fell off the rusted cable. I recovered all the parts and in better weather, investigated the possibilities of repairing the remains of the donut hanging system, rather than going to my "friendly" parts department armed robbery station. The rusty heads of the attachment bolts were a perfect fit in a 5/16 wrench, but no reasonable torque would get them to move so I used the most reasonable solution - beat upon the other end of the wrench with a BFH. Wonder of wonders, they came loose instead of twisting off - the bolts attached to these 5/16 hex heads with attached washers, were 8M1.25. After cleaning the winch and re-terminating the cable, I re-installed the assembly with standard headed hardware, and, as of last Sept. it was still functional.

I have in front of me, a 3/8-16 bolt with 5/16 hex. head/washer combo threaded into a hex. nut which measures 11/16 across flats - standardize that, if you please. Gerry :-)} London, Canada

Reply to
Gerald Miller

"Andrew VK3BFA" wrote in message news: snipped-for-privacy@42g2000cwt.googlegroups.com...

That's likely a cluster diamond. Very good for dressing if you want a flat surface, and if it's made from slender pieces of diamond that can't get rounded off like a larger diamond does in use, it could very well yield a pretty decent face on the wheel.

The only way you could tell if dressing beyond the diamond would be helpful would be to try with a star dresser or dressing stick. The improvement you noticed could have easily been simply because the wheel was trued well. It's not uncommon for wheels on large pedestal grinders to be abused, often used for rough grinding of weldments and other objects. A grinder that is dedicated to sharpening should have a wheel suited to that purpose, which will usually be poorly suited to other applications. Hard steel requires a softly bonded wheel, so the

Here's a link to a page that somewhat describes what I'm talking about.

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I'm shocked at the increase in price-although they're still very affordable. One will last a person for years on end, so they're a very good investment. I can well remember when they cost only a few dollars-----but then I also recall when gasoline was only 22¢.

A single point works fine for rounding up a wheel, but it's difficult to get a flat surface. They also round off with use, eventually dulling the grains of a wheel instead of cutting them clean. To avoid that scenario when using them as originally intended, to dress wheels on precision grinding machines (think surface, cylindrical or internal grinders) the diamond is held at a slight angle, usually about 10°, then rotated occasionally to present a sharp edge of the diamond to the wheel. The diamond can be pretty well used before requiring replacement if diligence in rotating is maintained. Regardless of the application, a dull diamond is not good to use because of what it does to the wheel. The only exception is if you're trying to shape the wheel (get it running true), and will touch it up with a dressing stick afterwards.

Correct. They work great when in good condition, but the stars wear and then they like to chatter. When they chatter, it's hard to round up the wheel, although they remove it at a good rate. Having said that, with a bit of talent on behalf of the operator, they're a good tool. I prefer to not use one, if for no other reason, they put up so damned much dust that it gets everywhere. A dressing stick is a very good compromise and requires very little talent to use. In my case, where I don't use a tool rest for grinding, the use of a star dresser is pretty much out, anyway. One needs a rest in order to use one successfully.

Not exactly. Both aluminum oxide and silicon carbide are much harder than steel---with silicon carbide being far harder than aluminum oxide, the wheel of choice for steel and steel alloys. There are some minor variations to what I'm going to say next, grinding on cast iron being one of them. The wheel of choice for that material is silicon carbide.

The problem with grinding steel with silicon carbide is that steel has an affinity for both carbon and silicon. At heat, the steel absorbs the wheel, dulling it almost instantly. While aluminum oxide is far softer, it isn't soluble in steel, thus holds up far better when used for grinding. Silicon carbide is used for pretty much all non-ferrous grinding.

What you're alluding to is the bond of the wheel, and you have it correct. For grinding hard objects, a wheel must be bonded soft enough for the dulled grains to shed, exposing sharp, fresh grains below or beyond those that are no longer performing well. They must also not shed prematurely, to insure a useable life of the wheel. For that reason, wheels that are intended for use in grinding hard substances are generally very soft. For a good example, a green silicon carbide wheel, intended for use in grinding tungsten carbide, sloughs off a at an accelerated rate when anything is applied. That's by design. In sharp contrast, the cheap aluminum oxide wheels that are typically supplied with the cheap bench grinders are usually so damned hard that they don't grind HSS or other heat treated things well at all. The object in question gets hot almost instantly, although you've not removed metal of any consequence. Remember----wheels are not harder or softer---only their bond is. The small exception to that rule is that each company may have various methods of producing the grains. In the case of aluminum oxide, Norton has a few different designations, each of which is tailored to specific grinding. Included amongst their designations are the numbers 19A, 32A and 38A., all of which are aluminum oxide wheels. The slight difference in hardness, if any, would not be noticeable, although each wheel performs certain duties better than the others. They are, of course, bonded accordingly.

Heh! It's almost safe to say the vast majority of information published regards tool grinding is wrong, at least not nearly as good as it could (should) be. For one, chip breakers are rarely addressed. Until you can grind a suitable chip breaker and understand what it takes to get it to perform properly, you really can't grind tools. They are not a luxury, they are a requirement for decent machining. The other fly in the ointment is that the majority of the books have instructions for grinding tools to be used in rocker type toolposts, so the information presented is useless for the modern machinist. The tools do not interchange.

I bought my lathe new in '67------the rocker tool post has never been used, although I still have it. Long ago man graduated past the idea of making single items. Working with a rocker tool post is one of the most demoralizing experiences I've ever had, but I was shocked into reality when, during the Viet Nam war, I was hired as a tool, die and gage man at a defense installation (Tooele Army Depot, in Utah). The shop was still using rocker toolposts, and we were trying to maintain military equipment vital to saving lives in Viet Nam. I hated the job so badly that I left after two months. You could spend hours doing a chore that would have been dealt with in minutes with proper tooling.

No big deal. Talking about it helps to refresh the things I was taught years ago. I've been off the machines (officially) since '83, although I still have them and use them on occasion. I hope to improve on that in the future, when I start building a model steam loco. BUT----the house I'm building must be finished first.

Harold

Reply to
Harold and Susan Vordos

My drill sharpener has a great solution for using a a single-point diamond to true the grinding wheel's side.

It has the diamond attached to a pivoting arm, with a "feed" for the diamond - so the diamond is used by turning the arm by hand (about 30 degrees) and the diamond always goes in the same level, 90 degrees to the rotational axle of the wheel. When the wheel is used, and you need to take more off, just advance the diamond a bit, and turn the arm again to make another pass with the diamond.

It's not that difficult to make a similar setup for the single-point diamond for the hand-grinder as well.. Just a linear guide and a hole with some fixture to hold the stick with the diamond at end.. Similar to how the "real" tool grinding machines do it. Of course, often not really necessary, but then it would be _true_. :)

Kristian Ukkonen.

Reply to
Kristian Ukkonen

On Tue, 26 Dec 2006 06:20:11 GMT, with neither quill nor qualm, "Harold and Susan Vordos" quickly quoth:

--snip of interesting dressing wheel info--

Excellent discourse, 'Arry. I found that I knew far, far less about grinding than I had imagined. This is a great post. Thanks.

What's "modern"? My $4 eBay copy of Ramond's _Modern Shop Practice_ is dated 1916. By "rocker tool post", do you mean the type also used on wood lathes with handled hand tools?

Suckage! You can instantly tell when Susan's mad at you after she installs that rocker tool rest on your lathe while you sleep, eh? ;)

Right. You never know much of your information base is missing until you try to teach it. It can be humbling, can't it?

Indeed! How's that coming, BTW? We need an update with JPGs, sir!

-- Friends Don't Let Friends Eat Turkey and Drive --

Reply to
Larry Jaques

Sreach on "dressing stick" at mcmaster.com, it looks like they had some listed cheaper.

I've also found them at my local "big box" store from time to time...

--Glenn Lyford

Reply to
glyford

snip---

Welcome!

That would be a T type tool rest. Not exactly the same thing. Rocker tool posts are also called lantern tool posts, at least they are today. They were simply rocker tool posts when I was coming up in the trade.

Rake angle is determined by placement of the T rest, as well as the attitude of the hand held turning tool as it relates to the centerline of the lathe. Rocker toolposts for carbon or HSS have holders with a predetermined rake angle built in. There is minor adjustment beyond that by how far out one mounts the cutting tool, and how far the holder is rolled up or down on the rocker to achieve center. Tools ground for use in these holders have way too much front clearance for use in zero rake holders. The exception to that is if you have holders for rocker type toolposts that are intended to be used with brazed carbide. They have zero rake.

Chip breakers are the source of rake angle in cutting tools that are held in zero rake holders, although you can grind rake without a breaker. Why you would, I don't know. Chip breakers often improve machining characteristics tremendously, beyond just simple rake grinding. As you become familiar with tool grinding, you come to realize the relationship between rake and front/side clearance in controlling hogging and chatter, to say nothing of chip control.

Chuckle! You appear to know her well! Actually, she's pretty mild mannered and very supportive of my endeavors. How many guys here have a wife that would have no problems if a new machine was hauled home? I'm encouraged at every turn to buy a CNC if that be my choice. We shall see, when the house is finished.

I've experienced that very thing lately in running the refining process for precious metals through my head. It's surprising how much I've forgotten in ten years.

Heh! It's coming, but you have to drive stakes to see the progress. I'm the slowest guy I know when it comes to construction work, easily spending a week on an hour project. In defense, when it's finished it's usually pretty well done.

The place looks like a house now, and is getting close to having drywall installed. We'd like to have that done for us--otherwise we may never get finished.

Thanks for asking. If you'd like to see a pic, contact me on the side and I'll send one, under 100 kb. I hesitate to post it---can't imagine many would have an interest.

Harold

Reply to
Harold and Susan Vordos

On Wed, 27 Dec 2006 09:08:28 GMT, with neither quill nor qualm, "Harold and Susan Vordos" quickly quoth:

OK, I finally got off my duff and googled it.

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Chip breakers are the source of rake angle in cutting tools that are held in

Some day I'll own a lathe (other than wood) and mill. Then I'll learn those properly. BUT, I can hardly see the other side of my shop right now having just demoed a kitchen for a lady and retained the (cheap) cabinets for the shop. 2,000 tools, a metalshop, a woodshop, machinery for both, welding equipment, a cubic meter of Jarrah wood, +++, all in a 2-car shop.

Cool!

I seem to remember squat from my '88 Coleman College Computer Electronics Technology (computer repair) course, but I only worked in electronics test for 3 years afterward, so I didn't really fill all the holes in my knowledge base about electronics in that time. I did, however, retain enough to work with a friend in repairing a bone densitometer which had taken a lightning strike. The intuition remained, I guess. (That was Terry if you're reading this, Gunner.)

So YOU are the source of the "furlongs per fortnight" measurement standard, are you? Verily, Susan is a saintette.

Isn't that what it's all about?

It's an art. I may learn some of it with my half bath near the shop. Methinks they painted oil over latex and it's all peeling. It HAS to be easier to re-drywall the beast than scrape and repaint. Drywall doesn't scrap or sand too well.

Sacre bleu! Why would any of the folks here not want to see the new support center for the Vordos CNCless PNW Machining Center? ;)

Pinging away. I want to see pics of your old castle, too.

-- Friends Don't Let Friends Eat Turkey and Drive --

Reply to
Larry Jaques

Machinists don't tend to make great rough carpenters nor do they hang drywall very fast either.

Wes S

Reply to
clutch

You got that right! I had a kid (with experience---one that had been running his own business, but was going through a divorce) finish the shop after using the fork lift to hang the ceiling, using 12' 5/8" firecode board. He was impressed! Did it all the old fashioned way, cutting openings by layout and a coping saw, and no nails. None. Little bastard got some advance money and never came back, so I ended up finishing the job, and it shows. I don't claim to have skills in that department. He got away with a little money, but left behind his stainless knife and pan. Maybe I should start a new business!

Harold

Harold

Reply to
Harold and Susan Vordos

Here's a link to the castle.

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It looks a little different now than it would have had we kept it. It was originally a two bedroom playpen with five bathrooms, a lab for refining precious metals, my humble machine shop, and a large stereo room. Like the house we're building now, it was designed around our toys, primarily the stereo system. It is now a well known B&B with ten rooms.

Pic of the current "house from hell" will be send shortly. I'm suffering with a bitch of a cold and don't have much energy. Heavy, heavy sigh!

Harold

Reply to
Harold and Susan Vordos

On Thu, 28 Dec 2006 09:17:23 GMT, with neither quill nor qualm, "Harold and Susan Vordos" quickly quoth:

Got it. Pretty wild.

I won't ask, Your Kinkiness.

I had that for most of November. Ugh! What I found to give immediate relief was powdered (buffered) vitamin C; 3 to 5 grams several times per day melted in 1/2 oz. of hot water and topped with 3 oz. of diet Dr. Pepper to remove the taste.

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came through for me when Vitacost (the spammers) failed, so I'm a happy, repeat Iherb customer.

-- My future starts when I wake up every morning... Every day I find something creative to do with my life. -- Miles Davis

Reply to
Larry Jaques

Hi Harold,

Wow! That is a pretty impressive old house. I'll have to curtsey and bow to your Highness from now on. I didn't realize we were keeping company with royalty here :)

I would be interested in seeing how your new place is coming along too. If it isn't too much trouble send some pictures my way too.

Do you happen to have a good Lat/Long for your new place too? If so include that in the same email so I can see what the area looks like on a map. That is if you don't mind.

Many Bows to your Highness and I hope you get well soon!

Reply to
Leon Fisk

Thanks, Leon. Right now, I wish someone besides me had this damned cold, but I've lived through them before----and expect I will again.

I'd be happy to send a pic or two, Leon. Please contact me on the side so I have your email addy. Should be able to get something out tonight. I'm still just sitting around feeling sorry for myself between naps. Don't know that I'd be able to provide the Lat/Long stuff you requested (don't know how to go about finding it)----but I can provide our address when I send the pics-----if that would help. Let me know.

Harold

Reply to
Harold and Susan Vordos

On Thu, 28 Dec 2006 23:37:30 GMT, with neither quill nor qualm, "Harold and Susan Vordos" quickly quoth:

Mine lasted two weeks and came back for a week's reprise. Ugh!

Aren't you near Onalaska, WA? I googled "onalaska latitude" and got:

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is roughly (not to 50,000 digits, Ig) 46.5995/-122.6654

-- My future starts when I wake up every morning... Every day I find something creative to do with my life. -- Miles Davis

Reply to
Larry Jaques

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Reply to
Steve Ackman

Hi Harold,

I sent a quick message/email that has a good addy that you can just reply too. It has the same subject line that this thread is using (forgot to change it, oops...)

Thanks!

Reply to
Leon Fisk

On Thu, 28 Dec 2006 09:08:18 GMT, with neither quill nor qualm, "Harold and Susan Vordos" quickly quoth:

I picked up a polished 6" knife, carbon steel 10" knife, plastic pan, roll of mesh tape, and a rubber sanding block in a kit last month. It was $10 at Wally World. 'Murrican made, too.

We'll be RICH!

Reply to
Larry Jaques

I'm pretty good at counting money, so you run the field work and I'll collect the money.

When do we start? :-)

H
Reply to
Harold and Susan Vordos

On Thu, 04 Jan 2007 05:58:53 GMT, with neither quill nor qualm, "Harold and Susan Vordos" quickly quoth:

First I'll need your non-refundable $100k Franchise Fee (cheap at twice the price!), then, if you're approved...

Reply to
Larry Jaques

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