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loply
12-21-2012, 08:05 AM
Hi folks,

I have a small Eagle manual surface grinder, and last week decided to skim the vice jaws on my mill. Afterwards I checked them and discovered they were sloping from top to bottom by about a thou (and also bent, but that's another issue!).

I decided to skim the mag chuck as it was in bad condition from when I got the grinder, so I covered it in WD40 and using an alum wheel took half thou's off until it was clean. The surface finish came out immaculate and it was cold to the touch throughout.

Trouble is when I then attach an indicator to the spindle and move the table around I find the chuck is 2 thou higher on the left than the right, and 2 thou higher on the operator's side than the rear!

Any idea what could be causing this? As stated the surface finish was really good, the gibs on the knee are in my opinion 'about right' (much tighter and the knee jerks/jumps as it's cranked up), and I was only taking half thou cuts. The machine is pretty much level, not perfect but within a thou or so.

Cheers,
Rich

Mcgyver
12-21-2012, 08:59 AM
I feel like I'm grasping at straws to explain away 2 thou with this.....but....sounds like what's being ground, in this case the chuck, isn't being supported and is flexing away from the wheel.....or heat is distorting things temporarily. Did you completely spark out? Even if it doesn't feel warm, you are putting energy into it, cold to the touch doesn't mean it isn't much warmer than when you started. Furthermore, based on its construction/geometry, who knows how it will change shape as it grows from the energy added. flood would be best so you know its temperature is close to the same start to finish....if you don't have it you might consider adding it, makes a big difference imo especially for grinding.

how well does the chuck mate with the table? maybe slightly grasping at straws here, but if there is debris there, or one surface isn't flat (warped chuck for example), I could see how if the chuck was only contact in a couple a places with a large bridge between the chuck could forced away from the wheel slightly causing those areas to end up high

I seem to recall installing a chuck involves a skim of the table? I'd start there....take the chuck off and indicate the table, skim in needed. with blue check the fit to the chuck

Tony Pratt
12-21-2012, 09:14 AM
Totally agree with Mcgyver on this, seems very strange! Also we used to grind our surface tables with the magnet on. Also when you indicate the table is it in the same location back to front on the slides as when you ground it?
Tony

JoeLee
12-21-2012, 09:32 AM
Was the magnet chuck in the on position when you ground it??? It should be when you dress it.

JL.............

George Bulliss
12-21-2012, 09:40 AM
It doesn’t take much to heat up a chuck and once heated up, they grow a lot. A half thou cut is more than I used to do for cleaning them. I typically would shoot for 1-2 tenths for the cleanup pass and would dress the wheel between every pass. Use a very open wheel for this.

Also, mark up the chuck with a marker before the finish passes. If all the marks come off while making a .0001” pass, it’s flat. If not, you have some more cranking to do. Take your time and never try to get one more pass out of the wheel before dressing; you can be there all day if you try taking shortcuts.

bborr01
12-21-2012, 11:06 AM
Like George said, very small cuts to avoid heat. But also, use a VERY LARGE step feed. When I would grind a chuck in, I would take only 1 or 2 tenths with flood coolant and step feet about 3/4 of the width of the wheel. Hope this helps.

Brian

loply
12-21-2012, 11:33 AM
Hi folks,

The machine is a dry grinder so I don't have flood, but I did cover it in a good layer of WD40 each pass. I also left it for quite a long time to cool down between passes.

The increments on the hand wheel are only in half thous, I can try to get less but the machine isn't that accurate that I can dial in a tenth reliably.

I was stepping in about half a wheel width. The magnet was on.

One thing I'm curious about is the technique for indicating the chuck - The chuck pulls the tip of the indicator which I presume isn't a problem generally speaking, but I wonder if means depending on the strength of the magnet I'm getting different readings? I need to verify the indicator arm rigidity I think.

Will take another look at everything and let you know what I can find.

Cheers,
Rich

Mcgyver
12-21-2012, 11:56 AM
also, use a VERY LARGE step feed.

what's the reasons for that? less chance of heat build up per pass?

George Bulliss
12-21-2012, 12:24 PM
I also use large cross feed steps. Can’t remember if it was beaten in my head by a toolmaker while an apprentice or picked up with time.

I think the reason for doing so is that a larger step over will use more of the wheel and spread the build-up over a larger area. A small step means only the leading edge is doing any cutting and the build-up will be concentrated in a smaller area, causing more problems.

When grinding the chuck on a dry grinder, I’ve used both WD-40 and Crisco on the chuck, with Crisco being the winner in my opinion. I’ve also used a cold gun (cold air blast) and that helps a bit too. It doesn’t take much to make the chuck worse than what you started with. Keep at it, keep the cuts as light as you can, and keep the wheel dressed and when you dress, dress it deep.

Richard King
12-21-2012, 12:48 PM
You all are overlooking what maybe the problem. The machine is worn? There is a real simple test to see if it is your grinding procedure or your machine. Do you own a steel or granite parallel as long as the mag chuck? If you do lay it on the chuck and indicate the middle 2/3's zero or a close as you can get it by using feeler gage under the ends. Use a tenths (.0001") indicator.

If the machine is worn then when you feed to the rest of the 1/3 travel the ends will raise. The opposite of the chuck grind. If you think about it the majority of your grinding is probably short and the table and saddle top ends don't get worn, so when you go to dress the chuck or table top they grind low on the edges.

Remember when your machine shop instructor told you to move your part around on the chuck or even on your mill vise, he was telling you that because the machine will get even wear. If you don't have a long parallel put your precision level on the chuck and shim it level when the table is centered, then slowly move the table out to the ends and watch the bubble. You will have to stop the movement and let the table come to a rest, which usually is 10 seconds on precision .0005"/12 level.

There is also another possibility I have seen in my 40+ years of machine rebuilding and scraping. The spindle bearings are bad or lose and when you near the ends and fall off the end of the chuck the wheel grind deeper and as it rolls up on to the chuck it stabilizes and grinds flatter. When I rebuilt a machine that was a dry machine I either used a air coolant sprayer or a hand pump squirt bottle and dress the wheel very open or coarse. I would also mount a dial indicator on the column and feed down in .0001" to .0002". .0005" with no coolant is to much. Check things out and let us know. I also grind 5 blocks on the machine when I am finished and indicate them on a plate to verify flatness. More on that later if needed. You can write me directly at Richard@handscraping.com or get my phone number there and call me.
Merry Christmas. Rich

Jaakko Fagerlund
12-21-2012, 02:02 PM
I think the reason for doing so is that a larger step over will use more of the wheel and spread the build-up over a larger area. A small step means only the leading edge is doing any cutting and the build-up will be concentrated in a smaller area, causing more problems.

When grinding the chuck on a dry grinder, I’ve used both WD-40 and Crisco on the chuck, with Crisco being the winner in my opinion. I’ve also used a cold gun (cold air blast) and that helps a bit too. It doesn’t take much to make the chuck worse than what you started with. Keep at it, keep the cuts as light as you can, and keep the wheel dressed and when you dress, dress it deep.
You are still taking away the same amount of metal total, so the heat input is the same.

The only reason to teach taking wide cuts is speeding up grinding operations and using the whole wheel so that when it clogs, it is clogged full width instead of just the very edge of it.

Harvey Melvin Richards
12-21-2012, 02:51 PM
You are still taking away the same amount of metal total, so the heat input is the same.

The only reason to teach taking wide cuts is speeding up grinding operations and using the whole wheel so that when it clogs, it is clogged full width instead of just the very edge of it.

Maybe I'm visualizing this wrong. but isn't the amount of metal being removed the depth of cut X the width of cut, omitting the radius of the wheel?

outlawspeeder
12-21-2012, 04:21 PM
I hate to point out something simple, but is it a table lube problem. I don't have a table but if it uses a one shot, "floats" the table, and by the end of your cut it is tight?

Only something to look at.

bborr01
12-21-2012, 06:16 PM
what's the reasons for that? less chance of heat build up per pass?

The way it was explained to me is that when you take smaller steps, the wheels edge breaks down on each pass and you end up with a dull cutting edge on your wheel before you get all the way across the chuck. Not that the wheel will not cut then but it is just better to have the wheel as sharp as possible for something like this.

Another thing is dressing the wheel. Dress with a quick pass over the wheel. Don't dawdle. If you dress too slow it has the same effect as glazing the wheel. And have a sharp diamond dresser. It is amazing how much different a grinding wheel will perform when it is dresses with a sharp diamond instead of a diamond that is all rounded off.

Brian

JoeLee
12-21-2012, 07:23 PM
I see a lot of good points mentioned here. Table and colume lube was mentioned in my manual as a possible cause to your problem If the colume is dry it may be sticking when lowered and as you work your way across the chuck surface the head may be dropping slightly.
Taking too heavy a cut could result in faster wheel wear so by the time you've worked your way across the chuck the wheel has worn and dulled / loaded resulting in a + indicated surface towards the end of the job.
If you have trouble reading in between the half thou graduations of your down feed dial and I know what thats like try mounting a dial on the head and watch it as you feed down. Then let it sit with the machine running and see if any vibration causes the head to settle.
As other have said a finish pass shoould be no more than a couple tenths.

JL.......................

_Paul_
12-21-2012, 11:40 PM
My 1920's Norton grinder is worn and does lift around 0.005 at the very end of the table travel I wonder if you have a similar problem?

tdmidget
12-22-2012, 03:38 AM
]I also use large cross feed steps. Can’t remember if it was beaten in my head by a toolmaker while an apprentice or picked up with time.

Wrong. Take less feed if you want to change your routine


I think the reason for doing so is that a larger step over will use more of the wheel and spread the build-up over a larger area. A small step means only the leading edge is doing any cutting and the build-up will be concentrated in a smaller area, causing more problems.
"Build up"? What is that? Nothing is building up, the wheel is wearing. You want the wear confined to a narrow area so that unworn wheel cuts on the next pass. If you feed half the wheel width then by the time you are halfway across the chuck, the whole wheel is worn. Feed .100 per pass and a 1/2 inch wheel is cutting to size 5 times longer. Sure the edge has worn more, but the last .100 is near new and cutting to size.


When grinding the chuck on a dry grinder, I’ve used both WD-40 and Crisco on the chuck, with Crisco being the winner in my opinion. I’ve also used a cold gun (cold air blast) and that helps a bit too. It doesn’t take much to make the chuck worse than what you started with. Keep at it, keep the cuts as light as you can, and keep the wheel dressed and when you dress, dress it deep.[/QUOTE]
The cold air gun is too localized to help with accuracy in my opinion. The WD40 makes a good cut but carries away little heat. Try soluble oil in a spray bottle. You can keep the chuck quite wet with practice. I do suspect wear due to poor grinding practices such as failure to use the entire surface, even if a little at a time. It could be a oneshot oiler. Try a thinner oil.
How are you indicating it? If the indicator is mounted on the spindle then it should read "0" everywhere no matter how bad the machine is. You are indicating from the same features you ground from. The real proof is in the pudding. Gring a piece that is fairly large for the chuck and check flatness. If it's good then your indication is at fault. Checking the chuck from the spindle that ground it will never tell you anything. When you check flatness be sure that that is what you check. The part must be resting 3 points the same height and check the side on the points. You cannot check flatness by placing a part on the plate and indicating the top side.

Jaakko Fagerlund
12-22-2012, 05:42 AM
tdmidget, heat is building up.

bborr01
12-22-2012, 09:57 AM
The cold air gun is too localized to help with accuracy in my opinion. The WD40 makes a good cut but carries away little heat. Try soluble oil in a spray bottle. You can keep the chuck quite wet with practice. I do suspect wear due to poor grinding practices such as failure to use the entire surface, even if a little at a time. It could be a oneshot oiler. Try a thinner oil.
How are you indicating it? If the indicator is mounted on the spindle then it should read "0" everywhere no matter how bad the machine is. You are indicating from the same features you ground from. The real proof is in the pudding. Gring a piece that is fairly large for the chuck and check flatness. If it's good then your indication is at fault. Checking the chuck from the spindle that ground it will never tell you anything. When you check flatness be sure that that is what you check. The part must be resting 3 points the same height and check the side on the points. You cannot check flatness by placing a part on the plate and indicating the top side.

TD,

You have not spent much time grinding have you?

Brian

George Bulliss
12-22-2012, 10:57 AM
By build-up, I meant the wheel loading up or clogging with the soft material of the chuck and agree with Jaakko that spreading the clogged area out across a larger area of the wheel helps. Not saying this is the only way to do it, but it's the way I did it.

I think just about everyone struggles with grinding in a chuck for the first few times and results like yours are not uncommon. I'm sure you do have wear and perhaps some other things going on with your grinder, but I wouldn't use the results of your grinding as an indication of anything other than your grinding.

tdmidget
12-22-2012, 11:00 AM
Just about 5 years of 10-12 hours per day if you include surface (Includes Blanchard), jig, centerless, and cylindrical.

Tell us about your vast experience.

Rich Carlstedt
12-22-2012, 12:18 PM
In reading the post, I have to ask, is the mag chuck on or off when you are doing your readings ?
Should be off IMHO

Also, is the dial indicator at the exact point where the wheel touches the mag surface?
Sometimes, if not at the point of contact, you can see some wierd readings.

The above does not answer your question on the problem, but may help decipher the cause.

Rich

Mcgyver
12-22-2012, 12:45 PM
In reading the post, I have to ask, is the mag chuck on or off when you are doing your readings ?
Should be off IMHO



that is good point and suggests another test. Using an anti-magnetic indicator, map the chuck on and off and compare....might give a hint as to whether poor contact between table and mag chuck is in part to blame.


One thing I'm curious about is the technique for indicating the chuck - The chuck pulls the tip of the indicator which I presume isn't a problem generally speaking, but I wonder if means depending on the strength of the magnet I'm getting different readings? I need to verify the indicator arm rigidity I think.


as Rich suggests, test with chuck off...better yet get an anti magnetic indicator. Did you try as i suggested indicating the table and checking the fit between table and chuck? I still think heat is an issue, can't see wd40 doing that much....but you're in debugging process so tests that eliminate things are a good start.


My 1920's Norton grinder is worn and does lift around 0.005 at the very end of the table travel I wonder if you have a similar problem?

maybe last night was just too late a night...but wouldn't grinding in situ remove error like this? wouldn't wear result in a non-flat surface being ground on the chuck? Said non flat surface could indicate zero from a point close to the wheel that ground the irregular surface. I can see ways worn to a curve, skimming the chuck grinds that curve into the chuck - its a curved surface but indicators zero. I suppose then to know if things are good you need to both indicate the chuck and check it for flatness a- indicating zero and flatness are not the same thing when the indicator readings are based on the ways it rode in the first place

Jaakko Fagerlund
12-22-2012, 04:32 PM
Just about 5 years of 10-12 hours per day if you include surface (Includes Blanchard), jig, centerless, and cylindrical.

Tell us about your vast experience.
And? I know a 60 year old guy who has machined all his life and still can't use a lathe properly, eventhough he was the lathe operator for his career!

Mcgyver
12-22-2012, 05:06 PM
And? I know a 60 year old guy who has machined all his life and still can't use a lathe properly, eventhough he was the lathe operator for his career!

i'm with you, not direct at TD, but in general this 'listen to me because I've being doing it for so many years' leaves me cold. There are plenty of hacks making chips for a living, the commercial guys i know complain about them all the time.....while a poster might be the greatest chip maker ever, its the internet; our only way of judging that is how sound the logic and explanation is as to the why. Explain the rational/engineering behind it, full stop. Highly credible guys like Forrest and John S imo are credible because the do exactly that and pretty much only that.

Spin Doctor
12-22-2012, 06:45 PM
This my two cents. When ever I have to grind anything on a surface grinder and I want it as flat as the machine can be I always use magnetic parallels and grind them in place. The part to be ground is then placed on top of the parallels with out turning the magnet off. Grinding bearing spacers in this way I was always able to get them within zero to .00005" in terms of parallelism of the ends.

tdmidget
12-22-2012, 07:26 PM
And? I know a 60 year old guy who has machined all his life and still can't use a lathe properly, eventhough he was the lathe operator for his career!

Looking in the mirror? Still waiting on your vast grinding experience.

Jaakko Fagerlund
12-23-2012, 04:48 AM
Looking in the mirror? Still waiting on your vast grinding experience.
Sorry but no, I'm only 30. My experience has nothing to do with this and as said, it doesn't prove anything, as anyone can claim whatever they want about anything. It is just if your text seems credible and if your claims/ideas/experience has some explanations behind them as to the why's 'n but's.

MichaelP
12-23-2012, 02:35 PM
Actually, I think Tdmidget's advice and explanations here are quite sound. The form could've been better, but the substance is OK.

Mcgyver
12-23-2012, 02:47 PM
TD,

You have not spent much time grinding have you?

Brian

what exactly from the paragraph you quoted did you find fault with? TD's comments on indications are the same as what I posted about - ie zero reading does not mean flat....why do you think this is wrong?

loply
12-23-2012, 03:33 PM
Hi folks,

Just been out and spent some time inspecting the machine. Here are some of my findings-

1) With the table removed, the bottom surface of the rear slideway on the saddle is 2 thou lower than the front one, measured by placing the same parallel on each and indicating it from the head. This error isn't removable by lifting the front of the knee or by tightening the knee's gibs.

2) With the saddle locked tight and the knee gibs well adjusted, a precision level on the table reveals that the ends of the table rise and fall as the table is moved left and right. It seemed that adjusting the table gibs tighter didn't really stop this from occurring.

3) With the table mounted, indicating it from the head, the front of the table is 3.5 thou higher than the rear


I'm a little bit exasperated at present, as all of these problems don't seem to go away by mere tightening of gibs, which is what you'd hope for. I would like to know how to indicate the ways of the knee to see if the knee is not sitting parallel to the spindle axis, but I'm not sure how.

At the moment I'm trying to decide if all of these problems can be rectified with ease, or, if the machine is just worn out of shape! It doesn't look so, all the ways almost look newly ground, smooth and evenly finished with no sign of wear, albeit no scrape marks either.

http://www.1stmachineryauctions.com/media/lot/5ffce0d176151d5f4107d8ddca71a52c1ecbfe71.jpg

Cheers,
Rich

Jaakko Fagerlund
12-23-2012, 05:49 PM
At the moment I'm trying to decide if all of these problems can be rectified with ease, or, if the machine is just worn out of shape! It doesn't look so, all the ways almost look newly ground, smooth and evenly finished with no sign of wear, albeit no scrape marks either.
I have seen some worn out machines that don't look like the ways are worn, until you see that there should be frosting on the whole surface! For example, the horizontal milling machine at work has this on its Y-axis, the top and bottom show nice frosted surface, but the usually used middle area is worn so much that all the frosting has gone away, but the surface still looks good.

tdmidget
12-23-2012, 06:05 PM
Hi folks,

Just been out and spent some time inspecting the machine. Here are some of my findings-


1) With the table removed, the bottom surface of the rear slideway on the saddle is 2 thou lower than the front one, measured by placing the same parallel on each and indicating it from the head. This error isn't removable by lifting the front of the knee or by tightening the knee's gibs.

Lifting the front of the knee would make it worse, not better. Try tightening the gibs on the knee at the top ONLY to the point of binding or at least some resistance. Lower the knee enough to take some pressure off. Indicate again and see if there is any change.


2) With the saddle locked tight and the knee gibs well adjusted, a precision level on the table reveals that the ends of the table rise and fall as the table is moved left and right. It seemed that adjusting the table gibs tighter didn't really stop this from occurring.
This common and caused by not using the full travel of the table.


3) With the table mounted, indicating it from the head, the front of the table is 3.5 thou higher than the rear
Not conclusive but seems consistent with the indication of the ways on the saddle. Might mean that the table surface and ways are not parallel.



I'm a little bit exasperated at present, as all of these problems don't seem to go away by mere tightening of gibs, which is what you'd hope for. I would like to know how to indicate the ways of the knee to see if the knee is not sitting parallel to the spindle axis, but I'm not sure how.

Remove the saddle and check them to the column ways with a precision square.


At the moment I'm trying to decide if all of these problems can be rectified with ease, or, if the machine is just worn out of shape! It doesn't look so, all the ways almost look newly ground, smooth and evenly finished with no sign of wear, albeit no scrape marks either.

If the ways are as good as they appear then the wear is in the knee and table slideways. You will need a precision straight edge and surface plate to check them. They can be scraped in to match the ways, assuming the ways are good.

http://www.1stmachineryauctions.com/media/lot/5ffce0d176151d5f4107d8ddca71a52c1ecbfe71.jpg

Cheers,
Rich

It's got simplicity going for it. As a home project it is repairable. You would put more time into it than it is worth but then you have skills that could be applied to scraping elsewhere.

oldtiffie
12-23-2012, 07:13 PM
Being charitable (Festive Season and all) - it seems that will be quite a project.

If it were me and I wanted to keep it, I'd put it in corner on a "to do" and "think about" list and sort out what really needs doing and what time, space and tools (and money) are required to do it. Unless I had another, I would not have a surface grinder or the floor and bench space it needed for the period of the project.

Richard King
12-23-2012, 11:50 PM
Can you remove the table and take some more pictures. If this is your machine it looks pretty rough to me. If the scraping is gone or you can't see any, then the machine is worn and no matter how tight you adjust the gib's it won't get better. I've scraped hundreds of grinders and i'm not guessing at the problem or what it could be. This design does not lead me to believe you could get much better then .0003" even after it is scraped. If there is a local machine rebuilder in your area have him come over and give you a quote to rebuild it and read his mind. Get a professions opinion who can look at it first hand. I don't charge for giving quotes.

loply
12-24-2012, 06:39 AM
Hi folks,

Thanks for the replies, I've got a few more things to try before I conclude that it needs rebuilt/rescraped, I want to bolt the machine down as even tough it's quite heavy (>600lbs) I've noticed I can rock the precision level a bit by pushing on the head, and I also want to have another look at the gibs, as they're an unusual design and the procedure for adjustment isn't clear.

Richard - That isn't my machine. They are all quite old, I think mine is from the 60s, but it appears to have had a bit of a rebuild at some point as some parts are distinctly 'fresh' looking. No flaking/frosting visible anywhere though.

One of the problems is that, unlike the machine pictured, the column on mine is cast onto the base, meaning getting the thing horizontal for scraping the column ways would be interesting!

The gib strips are built as in the picture below, and on most of them, tightening screw 'B' (of which there are 2 or 3 on each gib) tightens the slide, as well as tightening screw 'A'. If you tighten B first, then A, then it's difficult to tighten A as the gib is locked... If you tighten A first, then B, then the gib locks up as B tightens. You'd think that the procedure would be to loosely tighten 'B' then tighten 'A' as required before nipping up 'B', but inevitably nipping up 'B' then locks everything! It's all a bit fiddly.

http://i46.tinypic.com/2d17cxy.jpg

Cheers,
Rich

Richard King
12-24-2012, 12:51 PM
Set the gibs with a max of .0005" lost motion so there is an oil film. To tight will gall up the ways. The picture is for a tapered gib, but the technique is the same. Push release, zero indicator, pull release and that's the error.When pushing and pulling you will bend or stretch the metal a little, that's why you release it. If the ways and gibs are worn you may not be able to get it that tight it might bind up when it gets close to the ends of the travel. Ooops...not easy to put a pic on here ..or for me anyway. Email me and I will send you the picture via E-Mail and maybe you can add it to the post. Richard@handscraping.com

metalmagpie
12-26-2012, 12:02 AM
Even on a machine with no coolant setup you can jury-rig one by using a pond pump, a plastic bucket and some plastic tubing. I did that to rig flood coolant on my KO Lee 6x12 grinder when I had to grind in a mag chuck. Start with the chuck upside down and take a cleanup grind across the bottom, then right side up and do the top. You *have* to use flood coolant.

metalmagpie

JoeLee
12-26-2012, 01:13 AM
It doesn't look like a very good design for a surface grinder.

JL...............

Jaakko Fagerlund
12-26-2012, 05:08 AM
It doesn't look like a very good design for a surface grinder.

JL...............
Yup, looks more like a T&C grinder or a drill press.

loply
12-26-2012, 07:47 PM
Hi guys,

Thanks for all the help so far.

Richard - Please find some more pics of the machine below. I'm resigned now to the fact that it's just worn. This still surprises me a bit as the ways are distinctly unlike my other machines which show patterns or bright patches where the wear occurs most, whereas this grinder looks uniform in every spot, with no obvious worn spots. Maybe it's just worn so much that it's worn all over!

In any case I was wondering what the best approach will be for rebuilding this thing. My scraping is approaching the speed where this will be practical now, though I'm still struggling to get good points per inch. I'm still meaning to order a copy of Richard's DVD to see if I can sort that issue out.

I've read Connelly's book and his chapter on the horizontal mill closely resembles this machine. I think the sequence of steps to ensure that I don't make one thing worse by scraping another is the bit I'll struggle with the most, but with the machine laid on it's back and the right tools I think I'll manage.

I really had intended for the first machine that got this treatment to be my RF45 clone, alas, that was when I was blisfully unaware my surface grinder was knocking out dog's back legs'!

Anyway, before I can commence I need to acquire a few things so it may be a while but I'll post a thread with the outcome when I do.

Cheers,
Rich

http://www.vanmildert.net/vm/rich/sg1.jpg

http://www.vanmildert.net/vm/rich/sg2.jpg

http://www.vanmildert.net/vm/rich/sg3.jpg

http://www.vanmildert.net/vm/rich/sg4.jpg

Richard King
12-26-2012, 09:22 PM
I wanted to be polite as the one guy said it was Christmas... You grinder looks more like a mill then a grinder. The short saddle that rides on the knee needs to be scraped really close as if it is loose and rocks the multiple of the error will be 2 or 3 to one up on the chuck, I would imagine. The ways look worn and I don't see any scraping at all. If you can get a copy of the Sleshinger Book "Testing Machine Tools" it shows the disadvantage of a short saddle over a long saddle. Send me you Email address and I'll scan that page.
We can also work together on your rebuild and you can post pictures here OK? To bad you can't organize a rebuilding / scraping seminar over there because we could scrape your machine as a class project. I will be selling the DVD over the internet to download in a couple of months. My email address is Richard@handscraping.com Happy New Year...Cheers :-)