# Granite Plate



## PeterT (Nov 17, 2022)

After years of dithering I decided to bite the bullet. Its a 12x18x3" Grade B (overall unilateral flatness tolerance: ±0.0001"). Sourced from Sowa in Edmonton procured through DMH in Calgary. 
So the journey begins. I have to make a proper protection lid, for now 1/8" hardboard.

Does anyone have some favorite suppliers of bluing goop? I have a small tube somewhere, I'm actually not even sure its the same stuff. I see people have these hard rubber rollers to evenly distribute on the granite, is that like an art supply item maybe?






						12"x18" Grade B Black Granite Surface Plate - Inspection Surface Plates
					

12"x18" Grade B Black Granite Surface Plate - • Brand: STM<br>• Color : Black<br>• Material : Granite<br>• Overall Unilateral Flatness Tol. (Decimal Inch) : ±0.0001<br>• <a href="/INTERSHOP/static/BOS/Sowa-Site/Webshop_CA/Sowa-Webshop_CA/en_US/Catalogue-Pages/F20.pdf">Download catalogue page</a>




					www.sowatool.com


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## PeterT (Nov 17, 2022)

I'm going to start a new post on indicator stand, but just related to above, I pulled out my 'scribey block thingy'. It came from KBC long time ago & has seen little use. It does not have a balled end on the rod accessory like @Mcgyver showed us for square setting. The clamp is not a wonderful fit on the vertical post. I would have to modify or remake it to hold an indicator stem assembly. It does have an integrated fine adjustment pivot. The base underside has 2 flats either side of a notch. Don't know how flat it is yet. I have have seen old school indicator bases which have a pocketed recess on the face so the plate contact is kind of a peripheral ring area. It has 2 vertical dowel pins which must be there for a reason, but its evading me.

Anyway, I'm considering making a surface gage assembly dedicated to dial gage holding. Partly as an exercise in making a nice tool & partly because many of the used offerings on Ebay in my range look like they need work & who knows the history. Haven't decided yet. Likely I could pull a favor & get the base ground, or maybe scrape? I like the looks of Doug Ross design for example. So I'll make a new post when the time comes. Meanwhile if you have seen any plans or desirable features, keep them in mind.






						Surface Gage - HomemadeTools.net
					

I built this gage to use as a primary height and square gage, not as a surface gage, I have dedicated surface gages but I wanted to have a dedicated



					www.homemadetools.net


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## DPittman (Nov 17, 2022)

PeterT said:


> It has 2 vertical dowel pins which must be there for a reason, but its evading me.


My Browneand Sharp "scribey block thingy" also has those two pins that I've never understood either.  When you figure that out let me know too. 
Also my version is clearly marked "Not hardened", is there any good reason (other than cost maybe) one would want the base not hardened?  Every picture I see of this model on the interweb seems to be 





a hardened model.


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## whydontu (Nov 17, 2022)

The pins can be pushed down to use against an edge to scribe a line parallel to the edge.

Hardened or not hardened? The cheaper component is sacrificial. Using a hardened steel surface gauge on a cast iron surface plate risks scratching the surface plate, so gauges are available un-hardened. Better to have wear on a softer $$ surface gauge than on the $$$$ surface plate.


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## Canadium (Nov 17, 2022)

over the past year I've acquired at auctions 2 height gauges, a dial gauge holder, and a surface gauge but still just have a puny 9X12 surface plate. Was seriously considering buying a bigger plate but the want list just seems to have no end! I'm still kicking myself for not taking the pink granite Starrett 18X24 at a local auction about 5 years back. It had no bids and would have almost been free. At the time I was just thinking about wood working and my car seemed too small for the surface plate.


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## jcdammeyer (Nov 17, 2022)

I used mine a lot during the building of my Gingery Lathe.  Since then, not so much.  Perhaps because I have a DRO on the mill so scribing lines just isn't needed.

For checking flatness and scraping I used the Permatex Blue.


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## Dan Dubeau (Nov 17, 2022)

The pins are for riding along an edge.  Handy when using a test indicator in the surface gauge, for making sure assemblies are parallel.  I use them like that a lot in fixture building.


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## DPittman (Nov 17, 2022)

jcdammeyer said:


> I used mine a lot during the building of my Gingery Lathe.  Since then, not so much.  Perhaps because I have a DRO on the mill so scribing lines just isn't needed.
> 
> For checking flatness and scraping I used the Permatex Blue.
> View attachment 28034


Hey I've got a blue scribe just like that one on the left.  No brand name on mine and pretty basic.  I use mine for setting lathe tool height.


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## Rauce (Nov 17, 2022)

The rubber rollers are called brayers and are indeed an art supply item. 

I have the permatex brand Prussian blue as well.


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## PeterT (Nov 17, 2022)

Rauce said:


> The rubber rollers are called brayers and are indeed an art supply item.


aha, perfect, thanks


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## Dabbler (Nov 18, 2022)

PeterT said:


> After years of dithering I decided to bite the bullet.


congrats!

If you get any surface gauge we can easily scrape it to flat.

Usually your indicator is held in an attachment on a height gauge.  I have extra.


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## Canadium (Nov 18, 2022)

Rauce said:


> The rubber rollers are called brayers and are indeed an art supply item.
> 
> I have the permatex brand Prussian blue as well.


Whats your favorite source for the Permatex blue? I was looking for some a couple years back and found a wide range of prices, mostly either ridiculously expensive or out of stock. Ended up getting Dykem from KBC instead.


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## Dabbler (Nov 18, 2022)

I got mine from Fastenal.  Refills will have come from the Internet, unfortunately.


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## thestelster (Nov 18, 2022)

Canadium said:


> Whats your favorite source for the Permatex blue? I was looking for some a couple years back and found a wide range of prices, mostly either ridiculously expensive or out of stock. Ended up getting Dykem from KBC instead.





			https://www.amazon.ca/Permatex-80038-Prussian-Blue-75-Tube/dp/B000HBM86Q/ref=asc_df_B000HBM86Q/?tag=googlemobshop-20&linkCode=df0&hvadid=293033552569&hvpos=&hvnetw=g&hvrand=15428435749641052851&hvpone=&hvptwo=&hvqmt=&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=1002306&hvtargid=pla-487116926566&psc=1


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## Rauce (Nov 18, 2022)

Canadium said:


> Whats your favorite source for the Permatex blue? I was looking for some a couple years back and found a wide range of prices, mostly either ridiculously expensive or out of stock. Ended up getting Dykem from KBC instead.


I’m pretty sure I got it from Amazon just because it was easy. I’ve seen it at auto parts places though. I’d suggest just buying one or two of the little tubes, a little goes a long way and you don’t go through it very quickly.


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## trlvn (Nov 18, 2022)

PeterT said:


> The clamp is not a wonderful fit on the vertical post. I would have to modify or remake it to hold an indicator stem assembly.



Harold Hall's web site has some ideas for home made indicator accessories:












						Dial Test Indicator Accessories, and with other uses 01
					

Accessories for use with the a Dial Test Indicator, or a Dial Indicator, but with other uses, typically, a machine gaurd holder.




					www.homews.co.uk
				




There is also a Youtube video that gives a short overview of some of the gizmos.  For example, the round 'base' in the top-centre of the picture, above, is sized to fit the T-slots of his Myford lathe which makes it useful for tasks like centering stuff in the 4-jaw.

As an aside, after looking at the interchangeable parts that Hall made, it made me realize that the magnetic bases and related arms I've accumulated are a hodgepodge of sizes.  Some metric, some imperial and others that aren't a whole number in either measuring system!  If I was smart, I'd unload a bunch of them and aim for a set that is 'less diverse'.  

Craig
(I could swear there was a sketch with suggested dimensions but I can't seem to locate it.)


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## Proxule (Nov 18, 2022)

Dan Dubeau said:


> The pins are for riding along an edge.  Handy when using a test indicator in the surface gauge, for making sure assemblies are parallel.  I use them like that a lot in fixture building.


That is assuming the granite plate is ground properly at 90 degrees, I went thorugh this before too.


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## PeterT (Nov 18, 2022)

It looks like Dykem (a manufacturer name) also makes a high spot / Prussian blue in addition to layout blue. Maybe that's the confusion.
Yes the Amazon price is one of those berzerk outliers that seems to come up for some strange reason.
I've also heard a certain brands or formulas of high spot blues are more difficult to remove. I'll have to dig mine out & experiment a bit


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## L98Fiero (Nov 18, 2022)

Dabbler said:


> I got mine from Fastenal.  Refills will have come from the Internet, unfortunately.


Not sure about your branch but you can't get into my local Fastenal, maybe requires a special pass or something, and they don't do one off sales, you need an account, frankly, it's easier to set up an account at McMaster-Carr and get it from there.


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## jcdammeyer (Nov 18, 2022)

Since my tube was almost empty I took the plunge and ordered another.  Should be here tomorrow.  Use this search string at Amazon.ca
Permatex 80038 Prussian Blue.75 fl oz Tube       ​Amazon.ca


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## Dabbler (Nov 18, 2022)

@L98Fiero Fastenal doesn't carry it any more.  I bought their last 2 tubes 4 years ago.

I have an account. but I won't be ordering from them ever again.  I have contact with the Western Canadian Sales manager, and the simply don't want to do business with accounts less than 10K$ per year.  I think they are supremely stupid for this decision.


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## Tom O (Nov 18, 2022)

I took it out of the box then I used the box to cover and protect it.


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## phaxtris (Nov 18, 2022)

You can often get it auto parts suppliers, as Prussian blue is also used for gear marking compound when setting up differentials


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## Tom O (Nov 18, 2022)

I see some people that are using the red coloured one for scraping is there a difference between the two or is it to make the hands look cleaner?


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## Dabbler (Nov 18, 2022)

@Tom O Red spotting paste is used the same a blue:  nowadays the particle size is similar.

This is opposed to the now-more-popular water based yellow, red and blue coatings.  They contain far less dye and are less opaque.  They are great for getting near the target - say 5 tenths (perhaps a little less?).  If you are going for sub-tenths, then Prussian Blue seems opaque enough to see the high spots.  

I haven't heard that anything else comes close, but with new technology, it is always possible.


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## phaxtris (Nov 18, 2022)

In regard to the opacity of the Prussian blue

I don't know if this trick works for scraping, but when using blue or the yellow gear marking compound for setting up diff's, a lot of guys thin it out with a touch of gear oil to make the pattern easier to read, maybe it would work for this purpose as well ?


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## Dabbler (Nov 18, 2022)

If you use a brayer on a surface plate, little or no thinning is required.

If you are thinning it out -on a surface plate, it is because it has been applied a little thickly.  The coating, to be optimal, should be about a half-tenth thick.  If thinned the imprint is very faint (my friend Bert showed me this with Prussian Blue and Varsol).

Gears are another matter - and I'm not that guy.


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## PeterT (Nov 18, 2022)

What is the recommended cleaning solvent for Prussian blue (that wont create issues for the granite surface)


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## DPittman (Nov 18, 2022)

PeterT said:


> What is the recommended cleaning solvent for Prussian blue (that wont create issues for the granite surface)


Is there any solvent that could damage a granite surface plate?


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## PeterT (Nov 18, 2022)

Not sure about damage, granite porosity & permeability must every low. Staining or partial penetration maybe? Or adversely affecting another application of blue? For example some thinners have more of a light oily content than others, lacquer thinner &  kerosene feel that way to me. Vs. methanol, acetone, alcohol... more light end stuff. From memory, Prussian blue has some kind of viscous oil base but I just remember it didn't come off my fingers very quick LOL. 

Sounds like the trick is don't leave the blue on for extended period to begin with.






						How I got old prussian blue out of surface plate
					

Well- I got most of it...  Have a pink surface plate and used prussian blue on one part- and with various interruptions ended up putting on several layers which sat for some time.    I went to wipe it off with lighter fluid- and got some- but not all.  I then tried laquer solvent and it got  a...



					www.practicalmachinist.com


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## Dabbler (Nov 18, 2022)

PeterT said:


> What is the recommended cleaning solvent for Prussian blue (that wont create issues for the granite surface)


*Never *use anything oil based near a surface plate, including petroleum distillates such as Varsol.

I use a big box of Clorox ammoniated wipes for all surface plate cleaning, and have for 40 years.


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## DPittman (Nov 18, 2022)

I have no experience with a surface plate but have had lots of Prussian blue over my hands and everywhere else it seems.  I have an ancient tube of it that always seems to leak a bit.

If I did have a surface plate and had to remove Prussian blue off that simpler methods did not work well with, I would use carb cleaner.  I see one of the posters in that practicalmachinist thread suggested using brake cleaner.  Brake cleaner works pretty good on a lot of stuff but when it doesn't come off with brake cleaner I am almost always successful with carb cleaner.


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## PeterT (Nov 18, 2022)

Dabbler said:


> *Never *use anything oil based near a surface plate, including petroleum distillates such as Varsol.
> 
> I use a big box of Clorox ammoniated wipes for all surface plate cleaning, and have for 40 years.



Those wipes remove prussian blue?


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## Tecnico (Nov 18, 2022)

DPittman said:


> Hey I've got a blue scribe just like that one on the left.  No brand name on mine and pretty basic.  I use mine for setting lathe tool height.


I could have written this ^ post word for word!

Mine came from Busy Bee.

D


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## DPittman (Nov 18, 2022)

Tecnico said:


> I could have written this ^ post word for word!
> 
> Mine came from Busy Bee.
> 
> D


I got mine second hand but if I recall correctly I think it had an old "craftsman" sticker/label on it? It is almost for sure older than Busy Bee?


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## Dabbler (Nov 19, 2022)

PeterT said:


> Those wipes remove prussian blue?


Unless they've removed the ammonia, it cuts the binder/carrier.

The prussian blue carrier seems like an oil or grease, but if it were, it would do 'bad things' to the granite.  I have been warned by more than one T&D maker to keep all oils and greases away from my surface plate.  It seems bad for the structure of the granite, somehow.

this is hearsay, It has worked well for me.

-- but I haven't 'blued up' anything in about 6 years now....


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## Susquatch (Nov 19, 2022)

PeterT said:


> It looks like Dykem (a manufacturer name) also makes a high spot / Prussian blue in addition to layout blue.



Finally! An answer to a riddle that has been pestering the daylights out of me. 

I've been using some old Dykem with no problems for a thousand years. Then I ran out. The last can I got was crap! Waaaaaay too thick for testing fits, clearances, and interferences, etc. Got some Prussian Blue on amazon that worked fine. 

Now I know why the Dykem was foobarred. Thanks @PeterT !


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## Susquatch (Nov 19, 2022)

Dabbler said:


> @L98Fiero Fastenal doesn't carry it any more.  I bought their last 2 tubes 4 years ago.
> 
> I have an account. but I won't be ordering from them ever again.  I have contact with the Western Canadian Sales manager, and the simply don't want to do business with accounts less than 10K$ per year.  I think they are supremely stupid for this decision.



I hope that doesn't happen here. The local Fastenal store is still good to me. They prefer to sell me a box of screws but will even sell me 1 screw if I am willing to wait for them to ship it in. Your outlets policy sounds like a path to bankruptcy if you ask me.


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## Susquatch (Nov 19, 2022)

Tecnico said:


> I could have written this ^ post word for word!
> 
> Mine came from Busy Bee.
> 
> D



@DPittman & @Tecnico

You two guys need to make yourself a lathe height standard. You will NEVER regret it.

I usually recommend making one as the first project for any new lathe owner. Both of you have been around a lathe for a while now so I'm surprised you don't already have one. It's time.....

Lots of different designs out there. I made mine from a 1" diameter bolt. Some guys like to put a magnet in the head. I never did that and don't miss it. KISS.

Lots of guys on here have made one. Just google "lathe height standard" and pick your favorite design.


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## DPittman (Nov 19, 2022)

Susquatch said:


> @DPittman & @Tecnico
> 
> You two guys need to make yourself a lathe height standard. You will NEVER regret it.
> 
> ...


I actually had made one but I prefer the height gauge stand.


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## Chicken lights (Nov 19, 2022)

Dabbler said:


> @L98Fiero
> I have an account. but I won't be ordering from them ever again.  I have contact with the Western Canadian Sales manager, and the simply don't want to do business with accounts less than 10K$ per year.  I think they are supremely stupid for this decision.


That’s odd, even this spring I could walk into any eastern Fastenal and purchase, with no account. The only stipulation was no retail, you had to be a registered business. They are NOT my preferred place to shop but sometimes on the road I have no choice 

They quoted me on a bunch of grade 8 fasteners that my regular bolt place couldn’t come close to matching- so either they’re selling cheap junk OR willing to sell at a loss to gain new customers, I never found out 

Brafasco lost my business when they started enforcing their minimum $10 sale rule. I’m with you, if you don’t want small business then say so, it must be an accounting or inventory hassle.


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## Susquatch (Nov 19, 2022)

DPittman said:


> I actually had made one but I prefer the height gauge stand.



This is REALLY hard to understand..... How can a height gauge equal the ease of use and convenience of a standard?

I can only think of two possibities. Either you have the most creative novel way of using your height gauge, or you have the worst least practical way of using your center height standard. 

My standard is cut exactly to center height. I keep it on the bench beside my lathe where it is always handy. I place it on the flat way in front of the tool I am adjusting. I bring the tool to the side of the standard and raise and lower the tool until my finger and then finger nail cannot detect a difference in height between the standard and the tool tip. This will always be within a few thou of center even if I rush the job.


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## DPittman (Nov 19, 2022)

Susquatch said:


> This is REALLY hard to understand..... How can a height gauge equal the ease of use and convenience of a standard?
> 
> I can only think of two possibities. Either you have the most creative novel way of using your height gauge, or you have the worst least practical way of using your center height standard.
> 
> My standard is cut exactly to center height. I keep it on the bench beside my lathe where it is always handy. I place it on the flat way in front of the tool I am adjusting. I bring the tool to the side of the standard and raise and lower the tool until my finger and then finger nail cannot detect a difference in height between the standard and the tool tip. This will always be within a few thou of center even if I rush the job.


Just amounts to preference only, I use it the same way and get the same results.  I do sometimes flip back and forth from having the compound slide on and off and so sometimes depending on what tool setup I have going on, it is easier to set the tool height using the ways as the base vs using the cross slide as the base.  I don't think it's necessarily better but I don't think it's worse either.


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## Tecnico (Nov 19, 2022)

Susquatch said:


> @DPittman & @Tecnico
> 
> You two guys need to make yourself a lathe height standard. You will NEVER regret it.


LOL!  One more thing for the (making shop tools for the shop tools) to do list.  I haven't been using the HG for anything else lately so it stays at tool height.

D


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## PeterT (Nov 19, 2022)

Just in time for Xmas 






						Accessories & Aids for Biax Power Scrapers | DAPRA Corporation
					






					www.dapra.com


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## Susquatch (Nov 19, 2022)

DPittman said:


> Just amounts to preference only, I use it the same way and get the same results.  I do sometimes flip back and forth from having the compound slide on and off and so sometimes depending on what tool setup I have going on, it is easier to set the tool height using the ways as the base vs using the cross slide as the base.  I don't think it's necessarily better but I don't think it's worse either.



That's one of the reasons why my standard is designed to sit on the ways, not the cross-slide. I don't want it to matter what tool setup I have. But besides that, it's not always easy to position a tool over the cross-slide. 

Here is mine in use. I plan to mill a flat into it when I have nothing better to do. In the meantime it works fine as is.


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## whydontu (Nov 19, 2022)

Susquatch said:


> That's one of the reasons why my standard is designed to sit on the ways, not the cross-slide. I don't want it to matter what tool setup I have. But besides that, it's not always easy to position a tool over the cross-slide.
> 
> Here is mine in use. I plan to mill a flat into it when I have nothing better to do. In the meantime it works fine as is.
> 
> View attachment 28090


my version has a disc on top, machined to two half circles. My lathe center is 2.935” above the cross slide. Half the disc is 2.936”, the other half 2.934”. Takes seconds to confirm if the bit touches one side but not the other.


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## Susquatch (Nov 19, 2022)

whydontu said:


> my version has a disc on top, machined to two half circles. My lathe center is 2.935” above the cross slide. Half the disc is 2.936”, the other half 2.934”. Takes seconds to confirm if the bit touches one side but not the other.



I like this concept. It beats questioning yourself about how well you feel the difference. 

When I took the photo I posted above, I took some additional time to check my "feel". I don't seem to have much trouble feeling a thou one way or the other. Maybe that depends on the temperature and how I'm feeling that day though......

I like your concept though. It's almost like a go/no-go gauge. 


Mine goes right beside my tool and I use my finger or finger nail to detect the difference in height. It's really surprising how sensitive that is. I can feel a thou pretty reliably.


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## Dabbler (Nov 19, 2022)

Ever since I made my height gauge for my lathe it is in regular use.  I always found the ruler method to be slower and less accurate.

I find it surprising that none of my mentors have ever used one.


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## jcdammeyer (Nov 19, 2022)

Arrived this morning.


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## Dabbler (Nov 19, 2022)

Arrived where from?


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## jcdammeyer (Nov 19, 2022)

Dabbler said:


> Arrived where from?


Message #22.  Ordered from Amazon yesterday at 8:59AM.


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## DPittman (Nov 19, 2022)

So I dug out my old leaky tube of blue and see that it is also DYKEM brand.  Another interesting fact is that it contains paraffin oil.  

And brake fluid worked so so for removing it from the hands but carb cleaner worked much better!  (I know, I know...)


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## Dabbler (Nov 19, 2022)

I cannot imagine what the disrepancy here (over petroleum oil on surface plates) --- Perhaps paraffin oil has some kind of different characteristic than common petroleum oil.  Gosh, I've been so careful over the years!  But ammonia wipes would make sense now.


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## DPittman (Nov 19, 2022)

Dabbler said:


> I cannot imagine what the disrepancy here (over petroleum oil on surface plates) --- Perhaps paraffin oil has some kind of different characteristic than common petroleum oil.  Gosh, I've been so careful over the years!  But ammonia wipes would make sense now.


Oh ya I also forgot to mention the first ingredient says some like "petroleum" but it is not clear it's definitely petro-something.


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## phaxtris (Nov 19, 2022)

What's the problem with oil and surface plates ? Other than the staining? Does it break down the surface over time or something ?


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## DPittman (Nov 19, 2022)

phaxtris said:


> What's the problem with oil and surface plates ? Other than the staining? Does it break down the surface over time or something ?


I have no experience with surface plates but I can't imagine the surface could be broken down by any oil.  I'd guess the problem with oil is the possibility of it hanging on to grit or dirt?


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## phaxtris (Nov 19, 2022)

DPittman said:


> I have no experience with surface plates but I can't imagine the surface could be broken down by any oil.  I'd guess the problem with oil is the possibility of it hanging on to grit or dirt?



That's why I was wondering, granite is pretty tough, other than it stains quite easily, just curious as to what the reasoning is behind the no oil thing


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## Dabbler (Nov 19, 2022)

What I was warned over 40 years ago was that oil on the surface plate will help "break it down".  Tool makers are usually not long on explanations. When I was in their shops learning, I kept everything free of oil and perfectly clean of other debris.  To not do what they said was to risk losing shop privileges.


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## PeterT (Nov 19, 2022)

Mitutoyo recommends denatured alcohol (a petroleum product)





Don Baily Suburban Tool recommends a household cleaner (ammonia base) mostly as a cheaper version to Starrett's cleaner. I won't link his video its rather silly
I've seen some other references to ammonia wipes but also a warning that many may also have mild dose of muriatic acid which is a no-no.



			https://www.starrett.com/docs/default-source/msds/starrett-granite-surface-plate-cleaner-sds.pdf?sfvrsn=15
		

Starrett cleaner. A quick look at their SDS... looks petroleum-ish to me













						Granite Surface Plate Maintenance Do's & Don'ts from the Michelli experts
					

Proper granite surface plate maintenance protects your equipment so you get the longest possible life out of your investment.




					www.michelli.com
				



_2. Clean the surface plate often & keep it covered. Clean often, and do so with granite surface plate cleaner. The wrong cleaner could leave behind residue that attracts dust, or worse, cause the plate to wear. After cleaning, allow the plate to normalize to ensure accuracy. The appropriate amount of time ranges from 1-5 hours depending on its size.
4. Do not use a water-based cleaner or a volatile solvent to clean the granite surface plate. Both will chill the plate. Volatile solvents could lead to wear, while water-based cleaners will cause the surface plate to retain the water, leading to rust on fasteners and other metal components._

Found a few links about 'blue' removal, but more forum type chit-chat where anything goes: WD-40, MEK...


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## PeterT (Nov 19, 2022)




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## Brent H (Nov 19, 2022)

I have only cleaned the surface plate with some acetone.  For a bluing I have a 1/2” plate of glass to do the initial bluing test. That is usually pretty good.  

Packing things up now so plate has gone into a drawer (left over from cabinetry) with a side of files 






There is about 1/8” on top of the surface plate so that will get some bubble wrap and then a piece of plywood screwed across the top.


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## PeterT (Nov 26, 2022)

After looking at used/new 'height' accessories I came to a few personal conclusions, maybe right, maybe wrong. In terms of scribing parts some vertical distance from the surface plate, I don't really see myself doing what is essentially layout work like that a ton, maybe occasionally. I have a scribe block & it just isn't super useful IMO. The scribe point needs to be registered to something, it doesn't readily accomodate DTI, no balled end main rod. So putting more effort modifying it doesn't seem as appealing.

Measuring type surface height gages. I guess you zero reference, move to desired height, scribe a line. Or within reason contact the anvil on a part & read height. Some (but not all) allow replacing the scribe with a holder accessory for DTI. But now the main readout becomes kind of redundant because the DTI needs some master gage to reference off of, so it becomes a glorified levitation device. The dual beam style (digital or dial/digit) can get very spendy. The digital vernier style I'm guessing might be similar to same class calipers. Vernier style is not for my eyesight. The accuracy (when referenced & believable) for all these is +/- 0.001". 















So for this particular purpose I took advantage of Black Friday & ordered a Shars 8" dial height gage. I'm not expecting a Mitutoyo but hopefully won't be shite & will serve this particular need. The scribe anvil is removable to accommodate included/shop made DTI/dial holder accessory. I'll keep you posted


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## PeterT (Nov 26, 2022)

For what I'll call surface height comparison when a DTI or plunger indicator is used, I'm considering this path. I already have a Noga arm (left), what they call a centering indicator which has a stem intended to be grasped in mill/lathe collet chuck. What about making a nice steel base which slides on surface plate, it has a hole to attach the holder. Noga also makes arms with threaded ends (right) which could go into a tapped hole, presumably the same kind of arm assembly that goes into a mag block. The head already accommodates DTI dovetail, dial stem & has micro-adjust thumbscrew all integrated in the head.









Fisso concept (gasp $$$$)





I'm not sure if these granite based stands are meant to slide on a granite surface plate or be standalone. Different kind of pillar post & arm, also available seperate.
Basically I'm suggesting a shop made base to this kind of assembly


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## Dabbler (Nov 26, 2022)

@PeterT The height gauge you purchased is intended to do comparison measurements as well.  If you order a DTI 'kit' instead of a bare  DTI, it will include a bar that is intended to replace the scraper tool in your height gauge.  This bar holds your DTI.

There is no need for an expensive additional base (unless you _really _want one).


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## PeterT (Nov 26, 2022)

Squareness indicating might be a different animal again, or maybe integrated into above idea. I need to noodle this some more. I found a presumably shop made device very similar to what I was envisioning. 
Base is turned on lathe so has circular profile, at least on one edge. He machined a contact ring profile. DTI is mounted, registered to a square, now ready to measure relative squareness. He removed material in the base & presumably lapped, something I was also wondering about.


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## Dabbler (Nov 26, 2022)

nice!


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## PeterT (Nov 26, 2022)

Dabbler said:


> There is no need for an expensive additional base (unless you _really _want one).


 The shop made base was being mentioned if I use the Noga arm which has no base. The Noga granite base + arm combo is $$$ out of the question, I'm just showing a comparative picture. Replace granite with Peter lapped steel, I buy the arm seperate. Make sense?


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## Dabbler (Nov 26, 2022)

I don't think I said what I meant very clearly.

I understand you are thinking about making a base.  I was trying to say that you might not need one at all - that you can use your height gauge instead.


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## Dabbler (Nov 26, 2022)

Of course it is always a great project to make your own scratch gauge or measuring base!


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## PeterT (Nov 26, 2022)

Dabbler said:


> I understand you are thinking about making a base.  I was trying to say that you might not need one at all - that you can use your height gauge instead.


Exactly, that was my plan with the Shars. Use it as-is for scribing mode. Or, replace scribe anvil with DTI fitting & use in comparator mode. I think it comes with DTI fitting but If not, easy enough to make an adapter.


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