I suppose the first question is, are they
necessary enough to buy as opposed to just using a pristine, decent quality, glass lapping plate?
The latter are a lot cheaper and if for average hobbyist usage, they'd be flat enough, does a surface plate have some other characteristic that makes it, despite the extra spend, a worthwhile purchase?
I do have a spare, unused glass lapping plate, still in its packaging so that would mean not spending money.
But, eh, on the other hand, I quite
like spending a bit of money on my shop.
The second question is, what do we all think about the more 'budget' end of the granite surface plate market?
Dasqua do a reasonably priced selection. One of these: https://www.rdgtools.co.uk/acatalog/DASQUA-GRANITE-SURFACE-TABLE.html
I'm thinking the 300x300 or 400x400.
What about the unbranded types you see on eBay or AliExpress?
Finally, buying used. That seems to me to be a hell of a gamble; there don't ever seem to be that many available and even used they're not
that cheap and I fear a previous owner who may have used it to chop firewood on!
BTW, initial usage would be helping me get a better idea of the various critical surfaces whilst I'm improving my little 7x. After that, well, the usual metrology a hobbyist undertakes.
I would definitely consider used but would check at local equipment dealers rather than online. Several years ago, I purchased a 24" x 36" Challange brand cast iron surface plate. Buying locally gives you a chance to inspect the plate to be sure it's in good shape. Many times, surface plates get abused and an online seller has no idea what problems they might have. Before purchasing it, I looked on eBay to see what they were going for. There was a huge difference between the initial asking prices, and the actual selling prices.
Many of the original listings had asking prices between $900.00 and $1,300.00. Selling prices were generally in the range of $200.00 to $300.00. I found an exact copy of the one I was considering with an initial asking price of $900.00 and an actual selling price of $100.00. I took the listing to the seller and made the same offer. Luckily, he sold it to me for that price since he had no use for it. It was left as part of the building sale by the previous owner.
I normally wouldn't have purchased such a large plate. I already had a 12" x 18" one, but it wasn't quite big enough for some of the parts that needed inspection. This plate was originally purchased by the company I worked for. When the machine shop closed, it was sold to one of the employees. He used it in his commercial shop for several years along with a couple other cast iron and granite plates. When it came time for him to downsize, he kept a couple granite plates and sold several other plates with the building. Had he known I was looking for a plate I'm sure he would have sold it to me rather than sell it with the building. As it turned out the new owner just wanted to get rid of it so it turned out well for everyone
With used surface plates it seems the larger they are the less they go for. Anything over about 12" x 18" is so expensive to ship it generally appeals to the local market only. The plate I purchased weighs 475 lbs. The lifting handles weigh another 40 lbs. and the frame it sets on weighs 170 lbs., for a total of 685 lbs. I'm not sure what it would cost to ship today, but I can't imagine it would be cheap.
I suppose it comes down to what kind of projects you do and the accuracy required, or desired? I think many who do machining purely as a hobby pursue a much higher level of accuracy than is actually necessary to accomplish the task. There is nothing wrong with this, it is a bar of achievement, the payoff of gratification at setting a personal best. If making parts professionally, the goal is usually, to meet the required accuracy without wasting time/expense trying to exceed it.
I purchased my 18"x 24" granite plate, about 30 years ago and it has been a useful part of my shop ever since. Could I have done without it? Probably, as I rarely need to make super precision parts and when I do, I don't think the plate would be all that crucial. That being said, having the plate does make work go easier and with less worry.
So Yeah, buy the best plate you can afford!
I suppose the first question is, are they necessary enough to buy as opposed to just using a pristine, decent quality, glass lapping plate?
The latter are a lot cheaper and if for average hobbyist usage, they'd be flat enough, does a surface plate have some other characteristic that makes it, despite the extra spend, a worthwhile purchase?
I do have a spare, unused glass lapping plate, still in its packaging so that would mean not spending money.
But, eh, on the other hand, I quite like spending a bit of money on my shop.
The second question is, what do we all think about the more 'budget' end of the granite surface plate market?
Dasqua do a reasonably priced selection. One of these: https://www.rdgtools.co.uk/acatalog/DASQUA-GRANITE-SURFACE-TABLE.html
I'm thinking the 300x300 or 400x400.
What about the unbranded types you see on eBay or AliExpress?
Finally, buying used. That seems to me to be a hell of a gamble; there don't ever seem to be that many available and even used they're not that cheap and I fear a previous owner who may have used it to chop firewood on!
BTW, initial usage would be helping me get a better idea of the various critical surfaces whilst I'm improving my little 7x. After that, well, the usual metrology a hobbyist undertakes.
I ran across a Grade AA plate with a certificate that stated a max variation of 0." for an excellent price and bought it, looking back, I should have stuck with the smaller Grade A that I had (It was a crime of opportunity). Realistically a Grade B would have been fine, I think much depends on what you are doing.
I own many Dasqua Items and I like them all, I have been very satisfied with the quality of their equipment.
I suppose the first question is, are they necessary enough to buy as opposed to just using a pristine, decent quality, glass lapping plate?
The latter are a lot cheaper and if for average hobbyist usage, they'd be flat enough, does a surface plate have some other characteristic that makes it, despite the extra spend, a worthwhile purchase?
I do have a spare, unused glass lapping plate, still in its packaging so that would mean not spending money.
But, eh, on the other hand, I quite like spending a bit of money on my shop.
The second question is, what do we all think about the more 'budget' end of the granite surface plate market?
Dasqua do a reasonably priced selection. One of these: https://www.rdgtools.co.uk/acatalog/DASQUA-GRANITE-SURFACE-TABLE.html
I'm thinking the 300x300 or 400x400.
What about the unbranded types you see on eBay or AliExpress?
Finally, buying used. That seems to me to be a hell of a gamble; there don't ever seem to be that many available and even used they're not that cheap and I fear a previous owner who may have used it to chop firewood on!
BTW, initial usage would be helping me get a better idea of the various critical surfaces whilst I'm improving my little 7x. After that, well, the usual metrology a hobbyist undertakes.
I think granite surface plates are great.
I bought a 900x600 off of Ebay for £325 about 4 or 5 years ago, money very well spent, it is a Swedish manufacture - Johannson.
I bought a tall Tesa height gauge for £200 on Ebay and cleaned that up and it compliments the surface plate very well.
With a little bit of WD40 the Tesa height gauge glides across the plate.
Basically buying this gear is more like some kind of rental where you get the deposit back, look after the equipment and you will get your money back with no problem.
I think granite surface plates are great.
I bought a 900x600 off of Ebay for £325 about 4 or 5 years ago, money very well spent, it is a Swedish manufacture - Johannson.
I bought a tall Tesa height gauge for £200 on Ebay and cleaned that up and it compliments the surface plate very well.
With a little bit of WD40 the Tesa height gauge glides across the plate.
Basically buying this gear is more like some kind of rental where you get the deposit back, look after the equipment and you will get your money back with no problem.
I don't have the space for something that big, something around 400x400 is what I can sensibly store. The Dasqua 400x400 is well priced and it does seem their plates are reasonably well regarded.
Thanks for the headsup on the brand, I'll keep an eye out on eBay. Was your plate used?
Did I screw up? I went to an auction today that had a 24" square x 4" thick granite surface plate. It appeared to be in good condition with only a small chip on one corner. It went for $50.00. What should I expect to pay for one of these? Thanks in advance for the advice.
The plates are very nice to have and dont cost very much but the shipping is what kills the deal. A plate that size weighs in at about 200 pounds. I think you should have bid on it and let them load it for ya.
You should have picked it up. The plates are cheap enough for the ok quality ones. Usually it isn't the price of the plate that gets you, its the shipping. A nice big plate can get kind of heavy A high quality precision surface plate can cost some $$. The last shop I worked at had a pink granite surface plate so big I could drive my truck onto it. Thats if I would have put ramps up to it as it was about waist high
Surface plate prices really depend on the accuracy of the plate. Some are flat within a couple of Thousandth, these plates are very reasonably priced, others accurate within a couple of tenthousandth cost quite a bit more.
alright, so at an auction is there any easy way to tell the quality of the plate? I see on ebay that some are pink lab grade.