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View Full Version : Re-aligning a good vice.



.RC.
01-02-2011, 01:29 AM
Thought some may like to see how I went about aligning a top quality vice that was just out a bit... I did it mainly to practice my scraping for alignment skills... I found it a very interesting and well worth adventure, not only the finished product but I found getting there was the most valuable part..

First up it is a 6" vice that came with my milling machine when I bought it... It has performed top my expectations and only had a few niggling things wrong with it... I had no need to re-align it other then, because I wanted to...

I did not actually take pictures when I was doing it mainly because for all I knew it may have turned out a complete fail... Which amazingly it didn't..

So here goes...

First up a I disassembled the vice, and scraped the base flat to about 5 SPI (spots per inch) I discovered 130mm radius blades are best kept for people who are experienced Biax users.. The ends are easy to dig in..

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment001Custom.jpg

I then did a breaking up scrape on the opposite side.. Then placed it on the surface plate and found the lowest point and highest point... I discovered one end was 0.04mm higher then the other.. I got the pen out and marked out different stages so I had some idea where to scrape.. thusly

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment004Custom.jpg

I then scraped only for alignment at this stage, at no point did I spot the surface for contact, I did measurements as I went to keep an eye on my progress..

When I had it coming in at mostly the same height all over I started spotting it in... Eventually working up to this point

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment006Custom.jpg

Upon measuring I have one end 0.01mm (0.0004") higher then the other... TO me this is good enough... I could bring it lower with a couple more scraping passes if I wanted

Here is an X test with my "straight edge" which is a gib off a scrapped milling machine...

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment008Custom.jpg

.RC.
01-02-2011, 01:37 AM
The X test is to check for twist...

I then put a parallel across the "ways" and measured it.... The measurement came up with very minimal movement of the dial gauge. (Mitutoyo 0.01mm)

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment007Custom.jpg

Upon moving to the fixed jaw which is also made of cast iron, I scraped the top surface flat. I ended up going a bit silly with the required SPI and ended up with a fine even splattering over the surface... Probably nearing 25-30SPI

I started with this

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment009Custom.jpg

And ended with this.

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment011Custom.jpg

I then flipped it upside down and with the dial indicator worked out where to scrape by finding the highest side and working from there.

I could keep an eye on parallelism between the two sides with my straight edge along with the dial indicator together to complement one another.

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment013Custom.jpg

.RC.
01-02-2011, 01:40 AM
That is as far as I have got to at this stage... To be continued...

PeteF
01-02-2011, 03:01 AM
Thanks for putting the photos up RC, nice job! I appreciate you did this as much as an exercise as for the end result but for my own interest I was wondering how you feel this process (scraping for alignment) would compare to first milling/fly cutting the faces to align and then scraping for bearing?

Also, I can't recall if you have a surface grinder? When I finally get a few moments I'll go pick up my grinder and this would probably be a good process to go through for me to try it out, but grinding instead of scraping.

Pete

djc
01-02-2011, 03:54 AM
...I discovered 130mm radius blades are best kept for people who are experienced Biax users..

Lovely job.

Could you just expand slightly on this. What range of blades are available and what size should the inexperienced user use (larger or smaller radius)?

Thanks.

.RC.
01-02-2011, 04:10 AM
I really don't know Pete. It probably all depends on how accurate your setup is.. I have no doubt you could get better then what I have done with a grinder, but a grinder capable of doing it might cost a lot..

I don't have a surface grinder, just two tool and cutter grinders.. The little Chevalier and the WW2 era Macson #2 which I have to rescrape.. It was rescraped by the previous owner but I think he did not own a straight edge going by the banana shaped ways..

Onto more pictures..

I do not own a granite or cast iron square, and the only square I have that I trust is a Brown and Sharpe one... I had to get the plane where the jaw bolts on square to the movable jaw, so I set it up thusly... I could slide a 0.04mm feeler gauge just into the top..

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment022Custom.jpg

I scraped it square and got what I believe a good enough bearing for the hardened jaw to bare against... The bearing coverage is not all over the surface but it is over enough of it for a non wearing side..

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment023Custom.jpg

PeteF
01-02-2011, 04:21 AM
I really don't know Pete. It probably all depends on how accurate your setup is.. I have no doubt you could get better then what I have done with a grinder, but a grinder capable of doing it might cost a lot..

Ok, I couldn't get an idea of scale from the photos, by grinder "capable" do you mean for the size of that vice?


It was rescraped by the previous owner but I think he did not own a straight edge going by the banana shaped ways..

Ha ha, maybe it was the same guy who built parts of my house. If he owned a level he sure as heck didn't want to wear it out! :eek:

.RC.
01-02-2011, 04:30 AM
Ok, I couldn't get an idea of scale from the photos, by grinder "capable" do you mean for the size of that vice?

No I meant one accurate enough.. As I understand there are surface grinders and there are surface grinders.. Most can work to one type of accuracy standards, but to work to better standards means you have to jump up a notch in quality of machine.. A bit like a standard South Bend can do work up to a certain standard, but to work to higher standards means you need a 10EE with the resultant extra cost that is to buy.. But then I have never done any surface grinding so am probably talking out my arse...

.RC.
01-02-2011, 04:38 AM
Could you just expand slightly on this. What range of blades are available and what size should the inexperienced user use (larger or smaller radius)?



Generally the larger the radius, the wider the cut, but tilt it just a bit and you will put a deep scratch in what you are scraping..

I have madeup blades with a 130mm, 90mm and 60mm radius.. I use the 90 for roughing and 60 for finishing... If I wanted a better SPI (say 40) then I would move down to a 40mm radius blade..

oldtiffie
01-02-2011, 05:18 AM
http://www.dapra.com/biax/scrapers/blades.htm

oldtiffie
01-02-2011, 05:20 AM
Very nice job indeed .RC.

You should be very pleased with and proud of that job - and yourself.

jackary
01-02-2011, 06:06 AM
Totally agree with oldtiffie beautiful precise work.
Alan

Mcgyver
01-02-2011, 12:52 PM
way to go RC, that is an excellent scraping project that will add a lot value - you end of with a perfect vise. It could be ground, but the value of scraping is a) lots of guys don't have grinders and to a less extent b) it might be the more accurate approach. Reasons for b) include quality/condition of the grinder and the difficulties of eliminating clamping forces affecting things....whereas the scraping gets it to the flatness of your surface plate. I'll admit point b) is slightly ivory tower for this project; a skilled grinder on a half decent machine would have no trouble doing an excellent job, but the power of scraping projects like this is that it lets one work the the highest levels of accuracy with but simple hand tools

Warren
01-02-2011, 03:15 PM
RC, looking pretty good. I started on my Sheldon Lathe compound today. I''ll have to take some snaps.

Paul Alciatore
01-02-2011, 04:01 PM
Generally the larger the radius, the wider the cut, but tilt it just a bit and you will put a deep scratch in what you are scraping..

I have madeup blades with a 130mm, 90mm and 60mm radius.. I use the 90 for roughing and 60 for finishing... If I wanted a better SPI (say 40) then I would move down to a 40mm radius blade..

Interesting. I am a scraping wanna-be with no experience, but I would have thought the opposite choices would be made. A smaller radius would tend to cut deeper and would be used for roughing. While the longer radius would spread the cutting out over a larger area but the cut would be less deep. This would be both a finer cut and also have a better smoothing effect. I know that pressure and angle has something to do with it, but where and why am I wrong?

As I said I have no experience and am not argueing, just trying to learn.

PeteF
01-02-2011, 06:11 PM
I'll admit point b) is slightly ivory tower for this project; a skilled grinder on a half decent machine would have no trouble doing an excellent job, but the power of scraping projects like this is that it lets one work the the highest levels of accuracy with but simple hand tools

Just to answer the question I posed to RC then, as I don't think either of us knew the answer, a normal schmuck 6 x 12 surface grinder like this one http://grizzly.com/products/G5963 would be capable of at least correcting the alignment to similar accuracy as RC did by scraping?

Obviously I'm not trying to detract anything from RC's efforts, just curious as to how surface grinding compares to scraping for this type of application. Not having used a surface grinder before, but having just bought one, I'm very keen to sort out in my own mind when it should be used, what I should be expecting/aiming for, and when to go for the good old Mk I Armstrong method. RC's machines are generally bigger than mine, but it's likely I will rebuild a similar version of this vice once I have the grinder set up.

Pete

.RC.
01-04-2011, 04:23 AM
I have done a bit more...

Have scraped all six sides of the moving jaw, flat and square to each other.. I then had my first go at flaking.. I did some practice first on some scrap cast iron... This is on a side that the jaw bolts against so will not be visible when in use...

The other design you can see there is my attempt at butterfly frosting.. It is quite hard to do...

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment004Custom-1.jpg

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment005Custom-1.jpg

.RC.
01-04-2011, 04:30 AM
Now I have turned my attention tot he fixed jaw.. I initially thought this was hardened steel but I have discovered it is cast iron as well, so it is starting to get the treatment..

It has to be the same height when completed as the moving jaw, as this is a clone of a Kurt it is quite versatile on where you can position the jaws.. Here is a picture comparing it to the already scraped moving jaw for height..

I also checked it for squareness and one side or badly out of squareness by 0.1mm.. I broke out the 130mm radius blade (I have improved in my use of the Biax now) and slowed the Biax down to do some heavy roughing... Here is a pic of a cycle where I took off 0.03mm in one pass... It looks a lot of swarf for such a small amount removed..

I am finding it getting a bit tricky now on working out where to scrape and how much to take off.. As the part has to end up being square and flat and as well end up at a specific height.. I am aiming for a 0.01mm total tolerance..

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment006Custom-1.jpg

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment008Custom-1.jpg

Ed P
01-04-2011, 09:09 AM
My vice knowledge is limited. Should both of the jaws be perfecly square or should one be angled slightly to help counter lift when tightening down the workpiece?

Ed P

.RC.
01-04-2011, 02:21 PM
The design of the vice is such that when you tighten the movable jaw is forced downwards...

.RC.
01-07-2011, 05:05 PM
Have finished this vice off.. I sillily did some flaking on top of the fixed jaw... I did a lot of practice on some old scrap cast iron before I did this but hand flaking certainly is hard to learn and master..

First up checking to make sure the slot in the fixed jaw is parallel with the side

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment007Custom-1.jpg

Next up measuring up for parallelism. This complemented running the dial indicator across the top to confirm the readings..

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment008Custom-2.jpg

Then it was just a simple procedure to finish scraping for flatness and squareness.. And we end up with the finished article

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment010Custom-1.jpg

.RC.
01-07-2011, 05:06 PM
http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment011Custom-1.jpg

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment012Custom-1.jpg

And the next project which turned up in the mail yesterday, with a 36" one hopefully to turn up next week..

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment014Custom-1.jpg

.RC.
01-07-2011, 05:08 PM
And a picture of some of my practice flake marks

http://img.photobucket.com/albums/v606/OzRinger/6%20inch%20vice/vicealignment002Custom-1.jpg

daryl bane
01-07-2011, 05:27 PM
Alot of scrapers use the heel of their hand to bump the scraper for flaking. I think this would be a good way to contract Carpal Tunnel. I use a rubber mallet and get good consistent results. Sometimes it is helpful to Dykem blue the surface and put down some diagonal layout lines, so that you can just follow the lines as you're bumping. I find a regular scraping blade radius works fine. I have a Anderson handle and hold the handle end against my shoulder, holding the tool a bit less than vertical,and the blade never leaves the work. Practice is key,and you'll find that elusive half moon is easy to accomplish. We went over a few years ago to a olde time machine tool repair place here in Dallas. The equally olde time owner pulled out his scraper and with a well gnarled hand did some bump flaking. His marks looked like a neat row of silhouettes of a Gov't eagle. It was just the special way he held and hit the scraper.