Surface plate search

[Westline]

I have just started to try my hand at scraping and I need a surface plate.
I need some suggestion and some help.
Firstly what is better granite or cast iron.
Secondly can I make my own by getting 3 cast iron slabs and scrape A with B as a template then B with C as a template and then C with a template.
I heard this can be done but I need some expert advice.
And lastly if I have to buy who know of a place that will sell me a surface plate for less than a arm and a leg and ship it to the A$% end of the world (South Africa)
I tried Grizzly ($200 min order)
Enco (Can't ship so big outside of US.... Had great service from them.... Thumbs up guy's)
Busy Bee (does not ship so big outside US)

Anyone I missed.
My budget is max $70 for a 12x12 in SA it will cost me $400 for a 12X12.

Please help
Kobus

[SGW]

Granite or cast iron? Moore Special Tool Co., which probably represents the high-water mark of mechanical accuracy prior to electronics, lasers, etc. preferred cast iron surface plates.

For a home shop...I think I'd prefer granite as easier to maintain, but I doubt it matters much, as long as whatever you have is properly designed to be a surface plate. Moore's cast iron surface plates were heavily ribbed box structures.

You might try www.travers.com

[Duffy]

Surface Plate

If all else fails, try a monument works and see if they have a tombstone that had a corner knocked off, (was damaged,) on delivery.
I toured the Rock of Ages facility in Barre, Vermont. They supplied NASA, among others, with LARGE surface plates. When I asked, they admitted that they only have one set of grinding and polishing lines in the plant. Tombstones go for engraving and surface plates go for a test and a piece of paper that says "This is Flat" signed by an inspector. The "flatenning" process is identical for either product.

[Westline]

If all else fails, try a monument works and see if they have a tombstone that had a corner knocked off, (was damaged,) on delivery.
I toured the Rock of Ages facility in Barre, Vermont. They supplied NASA, among others, with LARGE surface plates. When I asked, they admitted that they only have one set of grinding and polishing lines in the plant. Tombstones go for engraving and surface plates go for a test and a piece of paper that says "This is Flat" signed by an inspector. The "flatenning" process is identical for either product.

Thats pretty intersting and a little scary.... How do you think counter top granite will hold up.
Just got a reply from Traverse seems like there may be hope.

[2ManyHobbies]

Around here, countertop granite is about 1" thick. That may work on a small scale. Small being 4x6 or so. Lots of people use cutoffs with paper for flattening small work.

If you've got access to thicker and can verify the flatness, I can't see why it wouldn't work. Use advertised plates to estimate how thick of a slab you need.

[SteveF]

That may be the case at Rock of Ages but I've watched the guys at Starrett. Once the gigantic Thompson grinder got it mostly flat it was then worked by hand to get it to a specific grade. One person measured the surface with an autocollimator and made a map. Then it went to another guy who used a piece of granite (IIRC maybe 4" wide and high by 18" long) and moved it around in a circular pattern with some abrasive compound to work down the high areas. Then back to the measuring guy and repeat. Kinda' doubt they did that with grave markers.

Steve

[Mcgyver]

Fedexing a low cost surface around the world just doesn't seem to make sense. Have you you've scoured the landscape? Before going to that extreme cost, I'd be looking hard for local vendors, you've probably done so, but man it just seems unbelievable that no one in the country carries the low cost import lines. South Africa is a big modern country you'd think with lots of machine shops servicing industry, mines etc, where do these guys get their stuff? There are tons of places in Canada selling the low cost surface plates and the countries are similar in size.....plus, given its prominence in the continent, probably is a major distribution area.... I'd even start phoning machine shops asking where they buy before making the international carriers rich

[saltmine]

See what you started, Mike? I also decided to try my hand at scraping (blame it on some guy's article in HSM). Fortunately, I live in the Southwest.
My first attempt was to order a reasonably sized granite from a tool supply in the Midwest. All fine & good....Except that the shipping costs were going to be about twice as much as the plate itself costs. Why? because the plate weighs 75 pounds, which, I'm told, exceeds the maximum weight UPS will accept (70 pounds) The supplier's shipping department claims that when they have attempted to ship these granites by UPS, they always get broken. So they want to ship by motor freight and want a "lift gate" and "forklift" charge....for 75 pounds of granite(??)

Fortunately, I only live a couple of hours drive from ACE Granite in Glendale, California, so I contacted them, and found that I can get a bigger granite for about the same price, if I pick it up myself. Shipping anything over 100 pounds must be murderous in terms of shipping costs.

Using a counter top? I don't think a counter top is thick enough to be dimensionally stable, first of all. And I'm pretty sure the surface flatness is nowhere near being useful for anything like scraping. Most people I know who use granite or marble counter tops are leather workers who don't really need laboratory grade AA granites to beat on with their leather working tools.

[Mcgyver]

hehe, thats me, causing havock at every turn

[jkilroy]

Counter tops will not do, tried that. I think I could make a flatter surface with a wood planer. Have you checked at local machine shops for possible second hand? Trade schools? I feel for ya, I don't like shipping costs inside the US, and overseas is crazy.

[saltmine]

Tried getting a second-hand plate from a trade school. Fortunately, I took along my 24" straight-edge. 0.10" deeper and the low spot in the middle would qualify one granite as a bowl. Another one was in six convenient pieces, what kind of glue do you use to bond black granite back together?

Almost bought one, but I didn't have a crane handy to pick it up.

The latest on my attempt to purchase a granite plate from Midwestern supplier....$75 +tax for the plate, $120 shipping, and I have to verify semi truck access and have a forklift available when it arrives (WTF??... The surface plate weighs 75 pounds...)

[Westline]

Fedexing a low cost surface around the world just doesn't seem to make sense. Have you you've scoured the landscape? Before going to that extreme cost, I'd be looking hard for local vendors, you've probably done so, but man it just seems unbelievable that no one in the country carries the low cost import lines. South Africa is a big modern country you'd think with lots of machine shops servicing industry, mines etc, where do these guys get their stuff? There are tons of places in Canada selling the low cost surface plates and the countries are similar in size.....plus, given its prominence in the continent, probably is a major distribution area.... I'd even start phoning machine shops asking where they buy before making the international carriers rich

I completly agree with you, I try and avoid import as far as possible but sometimes you just get stuck like now.
Yes SA is a great country trying climb out of the 3rd world image of the African continent but I think our supply problem is all about demand.
In SA we have a saying under the Afrikaans speaking people "n Boer maak n plan" translated it means a man makes a plan. ( it's like russian humour, looses alot in translation)
What I'm trying to say we are a Nation of fixers where function more than fashion counts.
We are in general good in trades but not craftsmen, in my neighbourhood you can't throw a spanner without hitting 2 mechanic's a panel beater and a plumber but say hand scraper and they say yes the thing you use to remove paint.
I even spoke to a friend of mine with his own wiring bussiness and most of his clients do cnc and water cutting but when I mentioned EDM and hand scraping he looked at me like I was making it up.
The hobby machinist market is not big at all in SA and thus tool suppliers don't. Stock what would not sell.
The advantage for me in doing scraping and EDM and even black oxide coating is it's a specialized field here and I have no competition to worry about.
We do have a few tool supplier that supply tools from China but again if they sell one a year they either don't stock it or they charge really high prices to make it worth there while.
Just to get back to my home machinst point we are a total of 2 South Africans on this site me and Plunger.
Any hoo enough complaining back to my search.
Wish me luck.

Kobus

[PeteF]

We are in the same situation in Australia, and this very topic has come up here many times before. With all due respect to our American friends, they don't seem to be able to comprehend there are virtually NO retailers in our countries who are setup to supply tooling to the home workshop market. Retailers would much prefer to sell to the business market, who won't blink at dropping a couple of $K on a surface plate for example if they can regain that outlay on a job(s). The hobbyists are very much viewed as "time wasters" for businesses in this area.

So far as your problem, having gone through the process myself I was finally able to find a retailer here who imports cheap Chinese tooling and was able to obtain a surface plate. It's still not as large as I'd prefer, but not too bad. I wouldn't waste my time trying to bodge something using a gravestone, what have you got at the end of it? You won't ever know how accurate it is, so what sort of reference is that! It's a bit like saying go get a strip of steel, tick off markings freehand along it, number them from 1 to 12 and say you now have a steel ruler!!!

I buy quite a lot from the US and warn that freight OUT of the US is very expensive. Just another kick to the US economy's goolies, but that's another story. If I were in SA I'd be making enquiries directly to Chinese manufacturers. However I'd respectfully suggest you simply won't get any form of plate landed in your country for US$70. To give you a comparison, the plate I bought (600 x 400 x 100) now sells for just under US$450 here!!! At the time I paid less than that, however that was before the retailer realised he had no competition and marked up all his prices 25%, despite the Australian dollar appreciating by a similar amount

Sorry that may not be a lot of help. I have been to South Africa many times and have a small understanding of what you're referring to with regards "making do". However in this instance a surface plate is either an accurate reference surface or it's not.

Pete

[saltmine]

Sounds a lot like my neighborhood, Kobus. I live in "the sticks" out in Northern Arizona and almost exactly like you described,"We are in general good in trades but not craftsmen, in my neighborhood you can't throw a spanner without hitting 2 mechanic's, a panel beater, and a plumber, but say hand scraper and they say yes the thing you use to remove paint."

Most of my neighbors believe paint is only good for graffiti. Which is why none of them have checking accounts (it's almost impossible to sign a check with an aerosol can of paint.)

I had to laugh. We have thousands of "mechanics" here, but nobody knows how to fix a car.
We have hundreds of builders, but they occupy their time stripping copper wire and plumbing out of empty houses, at night.
Almost every front yard has a disabled car rusting in it.(some have two or more)

BUT, on a positive note....I'm going to ACE Granite next week to pick up my first, brand new, factory fresh, black granite plate...Oh happy day. (and there's no dead guy's name chiseled into one side of it.)

[NzOldun]

Sounds a lot like my neighborhood, Kobus. I live in "the sticks" out in Northern Arizona and almost exactly like you described,"We are in general good in trades but not craftsmen, in my neighborhood you can't throw a spanner without hitting 2 mechanic's, a panel beater, and a plumber, but say hand scraper and they say yes the thing you use to remove paint."

Most of my neighbors believe paint is only good for graffiti. Which is why none of them have checking accounts (it's almost impossible to sign a check with an aerosol can of paint.)

I had to laugh. We have thousands of "mechanics" here, but nobody knows how to fix a car.
We have hundreds of builders, but they occupy their time stripping copper wire and plumbing out of empty houses, at night.
Almost every front yard has a disabled car rusting in it.(some have two or more)

BUT, on a positive note....I'm going to ACE Granite next week to pick up my first, brand new, factory fresh, black granite plate...Oh happy day. (and there's no dead guy's name chiseled into one side of it.)

You can do a rough check on the flatness with a just precision level

'Map' a layout for where you will place the level. on paper or in a spreadsheet. Place the level at at one corner, parallel to an edge and level the plate to the best that you can. Record the level (hopefully 0).
Shift the level along half it's length, allow to settle and record the reading. Repeat for the full length of the edge. Shift the level back to the first point but one 'width' over and repeat. Do this for the full width of the plate.

Repeat the entire process at right angles to the first traverses.

Lastly do the same for the two plate diagonals.

This should give you a map of highs and lows across the entire plate.

If you get less than .0005"/foot, all over, you have a very satisfactory plate for the home workshop. Anything a little higher is probably still OK, but then that will depend on what you want to use it for.

Alternatively, somewhere on this site there is a detailed example of using a laser to check the flatness of a surface plate. Sorry, but I can't track it down at the moment

Nzoldun