Flat Glass Surface

[massive propagator]

How do i go about making an ultra-flat glass sanding surface? I know i need float glass, but i dont really know where to go looking for this (im in the uk), or what type specifically i need.

Would buying a mirror be a good place to start? I assume even fairly thin glass will be ok mounted closely to a (very) flat piece of wood/metal?

Also are there any cheap alternatives i should consider?

I know its basic but i want to get it right.

[Woodenspoke]

"Float glass is more commonly known as window glass". I found this quote.

Any glass store will do, they cut glass to any size you need. I would assume a thicker piece will be easier to glue to a surface as they would be less likely to deform or crack. A 1/4 " thick piece is ideal, but probably a bit more expensive than the standard 1/8" size. Maybe you can find 3/16" thick glass if money is an issue. You can also have the edges ground down at the store so you don't cut yourself.

I remember Soapbar made leveling tools from glass.

[Prostheta]

I used a piece of glass from an award given to my wife as a levelling tool - around 1" thick, so it didn't flex although I wish it had been longer. Can't remember where it is now....

Not an award given to my wife on the basis of it being a levelling tool. I used the award. To be a levelling tool. She didn't want the award, if that makes me sound a little nicer, too. The flowers were nice though.

[RestorationAD]

I realize you were looking for glass in the UK but a surfaced piece of Granite would work. If you could find a local counter manufacturer they would have/be able to get surfaced granite

Here it is stateside.

Granite Block

[j. pierce]

Granted, It's probably not surface plate perfect, but I got a piece of polished ground granite/marble/some kind of stone from a local place that does stone works stuff - for free! I went in asking them if they had any surfaced stone they'd sell me, and they gave me a piece big enough to lap any plane sole I can think of for no cost. It was the cutoffs of a large piece, and not quite large enough to be worth their time. Now, I wouldn't trust this piece if I was a machinist or had really super tolerances in mind, but I can put straight edges across it any direction and can't fit feeler gauges under the edge anywhere, so that's good enough for me. And it was free. I used it when lapping my plane soles, and sharpening blades when I'm using the wet-dry paper method.

I don't know what applications you're looking for using the glass for, but thought I'd throw this out there.

[Woodenspoke]

I used a piece of glass from an award given to my wife as a levelling tool

You have a very understanding wife or you didnt tell her?

I can see it now "Honey have you seen my award"

[Racer X]

I actually have a glass chessboard that I use to sand the tops and back of bodies, and it works nicely for me. I adhere full pages of paper to it, and instead of drawing the paper across the body, I draw the body across the paper, using my handle I have mounted to the neck holes, with one hand, and applying necessary pressure to the body with the other hand. So far, so good, I'd say.