• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.
  • PLEASE: Read the FORUM RULES BEFORE registering!

4

Well I've gathered stuff to practice scraping.

3
Like what you see?
Click here to donate to this forum and upgrade your account!
10

expressline99

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Nov 29, 2015
Messages
402
Likes
159
#1
Well today I went around town and gathered some simple supplies to scrape... Prussian blue (at Napa), a decent file & handle from Home Depot to convert to a scraper, a rubber roller from a craft store.

I've got a small surface plate that I'm sure is out of cert if it ever was in. But it's free and was given to me from a job site where it was being a door stop for who knows how long... at least the working surface was face up!

The item to be worked on is an milling table for a drill press. It's missing the vise so the top is just an open dovetail. But that part is mounted on another dovetail that is complete with a gib. It's small and looks like it was just rough milled into the condition its in now. It's cast iron. End value of it being just an item to practice on.

I've been reading tons...watching all the videos. Reading the machine restoration book as recommended.

Should be fun....Doing this while I wait for parts on the Bridgeport full head rebuild.

Paul
 

Bob Korves

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Jul 2, 2014
Messages
4,032
Likes
4,181
#2
Paul, come on down and we will get a scraping session going, and get a couple others to come join in as well, perhaps talk Ulma Doctor into being the resident guru to keep us on the straight and narrow... Working with others helps one to see the different techniques that will work and gives a chance to talk about what we are doing and why it works for us. Also gives you a chance to try out different tools and techniques. None of us are by any means pros, just aficionados...
 

expressline99

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Nov 29, 2015
Messages
402
Likes
159
#3
Bob, I really need to make it over there. Gotta work on wife for next month. I need something for her and the two kids to do over there while I'm visiting.
 

4gsr

HM Chief Foreman
Staff member
H-M Supporter-Premium Member
Joined
Aug 8, 2011
Messages
4,404
Likes
2,665
#4
Before doing any scraping, get one of the guys check your "free" surface plate against theirs. If you don't, you could be chasing your tail on tyring to get something flat or even determining if something is flat. Both these guys would be a great mentor for you! Ken
 

Bob Korves

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Jul 2, 2014
Messages
4,032
Likes
4,181
#5
Paul, we could rub your surface plate against one of ours, which have recently been professionally calibrated by Precision Granite to AA and certified to A grade. If they match, great. If not, "Man with one watch knows what time it is..." None of us have an autocollimator, or a repeat-o-meter, or anything similar to actually calibrate them.

edit: Sacramento Zoo is a fun place to go, also the great railroad museum in Old Sac.
 

expressline99

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Nov 29, 2015
Messages
402
Likes
159
#10
Paul, we could rub your surface plate against one of ours, which have recently been professionally calibrated by Precision Granite to AA and certified to A grade. If they match, great. If not, "Man with one watch knows what time it is..." None of us have an autocollimator, or a repeat-o-meter, or anything similar to actually calibrate them.

edit: Sacramento Zoo is a fun place to go, also the great railroad museum in Old Sac.
Honestly I might be embarrassed to allow anyone to see this granite block. I have no idea where it's been other than it was found being a door stop at a house where I guy used to make knives. He was no longer around to explain... There are no identifying marks on it..it's a black granite? If it got close to other nicer plates it might upset them. :)
 

expressline99

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Nov 29, 2015
Messages
402
Likes
159
#11
Before doing any scraping, get one of the guys check your "free" surface plate against theirs. If you don't, you could be chasing your tail on tyring to get something flat or even determining if something is flat. Both these guys would be a great mentor for you! Ken
I need all the help I can get with learning! :)
 

expressline99

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Nov 29, 2015
Messages
402
Likes
159
#12
Paul, we can also show you the Canode water based inks. They are a LOT less messy than Prussian blue, which does work fine.
I should have done a multi-quote but anyhow. This is new to me all around. This blue is certainly messy. I just assumed that was part of the bit of doing this.
Paul
 

ghostdncr

Active Member
Active Member
Joined
Mar 5, 2017
Messages
123
Likes
84
#13
Honestly I might be embarrassed to allow anyone to see this granite block. I have no idea where it's been other than it was found being a door stop at a house where I guy used to make knives. He was no longer around to explain... There are no identifying marks on it..it's a black granite? If it got close to other nicer plates it might upset them. :)
Have you got anything you know to be relatively flat of some considerable size? If you do, put a thin skim of that Prussian blue on it and gently float it over that surface plate. Hardly NIST stuff, but under a strong backlight it will suggest what you're dealing with.
 

Bob Korves

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Jul 2, 2014
Messages
4,032
Likes
4,181
#14
Honestly I might be embarrassed to allow anyone to see this granite block. I have no idea where it's been other than it was found being a door stop at a house where I guy used to make knives. He was no longer around to explain... There are no identifying marks on it..it's a black granite? If it got close to other nicer plates it might upset them. :)
Surface plates have nothing to do with beauty contests. They just need to be flat, damned flat! Eyeballs are worthless at checking them. A single test is worth a lot of opinions... Bring it on! We can also put it on top of one of our calibrated surface plates and chase a tenths indicator around the top surface, then turn it over and check the other side. If done a few times on different parts of my plate, and we get the same results, I think you could keep the results in mind while you use it until you can get it calibrated properly or replaced.
 

expressline99

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Nov 29, 2015
Messages
402
Likes
159
#15
Surface plates have nothing to do with beauty contests. They just need to be flat, damned flat! Eyeballs are worthless at checking them. A single test is worth a lot of opinions... Bring it on! We can also put it on top of one of our calibrated surface plates and chase a tenths indicator around the top surface, then turn it over and check the other side. If done a few times on different parts of my plate, and we get the same results, I think you could keep the results in mind while you use it until you can get it calibrated properly or replaced.
Oddly the bottom side of the thing is rough cut and even has a big saw mark and is unfinished. I think it can certainly be looked at by you guys. It's portable enough. If nothing else I can be told it needs to go back to holding a door. Either way there would be a result and that's a start.
 

expressline99

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Nov 29, 2015
Messages
402
Likes
159
#16
Have you got anything you know to be relatively flat of some considerable size? If you do, put a thin skim of that Prussian blue on it and gently float it over that surface plate. Hardly NIST stuff, but under a strong backlight it will suggest what you're dealing with.
I honestly don't have anything else even close to flat. It would at least tell me if there was a huge dip through the center.
 

Bob Korves

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Jul 2, 2014
Messages
4,032
Likes
4,181
#18
I totally blew off the fact that the bottom of surface plates are rough cut, and useless for anything beyond holding up the top surface. Still, we can level the top surface with shims underneath and then indicate the top to look for dish or crown or other issues. What size is the plate? A lot of checking parts and comparing stuff is done with small plates like a comparator uses. I wish I had one...

Edit: Maybe we could put Ulma Doctor's .00005" (that is 50 millionths) DTI to work...
 

ghostdncr

Active Member
Active Member
Joined
Mar 5, 2017
Messages
123
Likes
84
#19
I honestly don't have anything else even close to flat. It would at least tell me if there was a huge dip through the center.
A good piece of plate glass would give you an idea of what you're working with. No clue what kind of tolerances modern glass is made to, but it's pretty flat. I used to have a 1/2" thick piece that I'd lay on a cast iron surface plate to serve as a backing plate for a sheet of wet or dry sandpaper. Real handy for cosmetic flattening and producing that matte swirled finish on material prior to engraving. Just a thought...
 

Bob Korves

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Jul 2, 2014
Messages
4,032
Likes
4,181
#20
Plate glass is ground and polished and it is pretty flat, but certainly not calibrated surface plate flat, it is not designed or made for that purpose. Float glass, less so, but not really bad. Same with granite counter tops. Ordinary window glass, you can see the ripples in it...
 

Ulma Doctor

Infinitely Curious
Active Member
Joined
Feb 2, 2013
Messages
4,296
Likes
3,495
#23
Very nice scraper!
maybe you could construct one too if you had the desire and braze a pre-sharpened blade insert to it, or create a blade lock similar to the Sandvik or the Anderson and use inserts as intended
then you need to be able to sharpen carbide.
... and then the rabbit hole has been entered.....:grin:
 

4gsr

HM Chief Foreman
Staff member
H-M Supporter-Premium Member
Joined
Aug 8, 2011
Messages
4,404
Likes
2,665
#24
......
... and then the rabbit hole has been entered.....:grin:
And it's a deeeeep hole at that, too!

Next will be a scraped cast iron straight edges. Not just one, at least three of them in lengths up to 48"
Like Mike mentioned a carbide grinder. Not just a grinder, it's actually a lapper with the correct blade.
And almost have to have, a Biax power scraper with the tool pouch. And the list goes on and on...
Did I mentioned a planer?:eek:
 

expressline99

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Nov 29, 2015
Messages
402
Likes
159
#25
Very nice scraper!
maybe you could construct one too if you had the desire and braze a pre-sharpened blade insert to it, or create a blade lock similar to the Sandvik or the Anderson and use inserts as intended
then you need to be able to sharpen carbide.
... and then the rabbit hole has been entered.....:grin:
Well I have an acetylene setup so I could probably figure out how to do that. I need a rosebud for it though. But there are several tips laying around. It's got a victor 100 head/mixer/handle?

A blade lock... that would be an interesting quick project. I need some simple ones to do with the mill once it's back together. Can I sharpen carbide with a green grinding wheel? I have one of those around I've never mounted....I think I bought it for messing with bronze.
 

Bob Korves

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Jul 2, 2014
Messages
4,032
Likes
4,181
#26
Paul, the second 20 in the part number is the width, in millimeters. That is slightly over 3/4" wide. That size would be good for finish scraping and for smaller work and large dovetails. For general work on larger surfaces, a 25mm or 1" width would probably be more generally useful. I have a pack of new 30mm Sandvik carbide scraper blades and you are welcome to one when you come visit. It is not difficult to make a scraping tool, and there are several common designs that you might copy to build yourself to fit you and your preferences. The 30 mm blade can be left as it is, or ground down to whatever size you desire. The Sandvik tools are nice, but are pretty cheap and easy to copy.
 

expressline99

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Nov 29, 2015
Messages
402
Likes
159
#27
And it's a deeeeep hole at that, too!

Next will be a scraped cast iron straight edges. Not just one, at least three of them in lengths up to 48"
Like Mike mentioned a carbide grinder. Not just a grinder, it's actually a lapper with the correct blade.
And almost have to have, a Biax power scraper with the tool pouch. And the list goes on and on...
Did I mentioned a planer?:eek:
Well I'm in process of getting those straight edges going already. I guess I have to look up what a carbide grinder is... The Biax scraper I'm already slobbering over and have been since I saw the first video that showed one!

Now on the planer thing....I've actually look for one of those. All I can find are very large machines! I was thinking a metal shaper until I figured out they made planers. Then then the size changed because I'd have to have a planer or a shaper with at least 24" probably 36" travel... those are a bit big for my garage. But I've yet to see a planer that was small or even medium sized.

oooh the excitement!
 

Bob Korves

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Jul 2, 2014
Messages
4,032
Likes
4,181
#28
Yes, a green wheel will grind carbide, but it will need to be honed to finish it sharp and true. I know a fellow near here who has a small planer, from the 1800's, that is hand operated. It is tiny... He also has at least 5 more planers, up to BIG, a couple are from the 1860's, in beautiful original condition, and a lot of other really cool stuff!
 

expressline99

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Nov 29, 2015
Messages
402
Likes
159
#29
I totally blew off the fact that the bottom of surface plates are rough cut, and useless for anything beyond holding up the top surface. Still, we can level the top surface with shims underneath and then indicate the top to look for dish or crown or other issues. What size is the plate? A lot of checking parts and comparing stuff is done with small plates like a comparator uses. I wish I had one...

Edit: Maybe we could put Ulma Doctor's .00005" (that is 50 millionths) DTI to work...
OK the size of the plate is: 12x9 3" thick.


Paul, the second 20 in the part number is the width, in millimeters. That is slightly over 3/4" wide. That size would be good for finish scraping and for smaller work and large dovetails. For general work on larger surfaces, a 25mm or 1" width would probably be more generally useful. I have a pack of new 30mm Sandvik carbide scraper blades and you are welcome to one when you come visit. It is not difficult to make a scraping tool, and there are several common designs that you might copy to build yourself to fit you and your preferences. The 30 mm blade can be left as it is, or ground down to whatever size you desire. The Sandvik tools are nice, but are pretty cheap and easy to copy.
Seems like making one might be the way to go? The plan is to scrape in my compound, cross slide and bed of my logan once I get going on it.
 
Last edited:

expressline99

H-M Supporter - Premium Member
H-M Supporter-Premium Member
Joined
Nov 29, 2015
Messages
402
Likes
159
#30
Yes, a green wheel will grind carbide, but it will need to be honed to finish it sharp and true. I know a fellow near here who has a small planer, from the 1800's, that is hand operated. It is tiny... He also has at least 5 more planers, up to BIG, a couple are from the 1860's, in beautiful original condition, and a lot of other really cool stuff!
I think I would pass out if I got to see all that in person. :excitement:
 
6
5 7