SBrown said:
Palladium said:
http://www.labx.com/v2/adsearch/detail3.cfm?adnumb=474837
Here's one in your area. It didn't sell on auction so their may be a deal to be had.
Thank you Sir, that is the exact one I saw on eBay awhile back. I'm going to contact them and see what I can work out.
It's not plastic, but it's better, ceramic.
Scott
One that size costs about $1000-$1500, or more, new. I've had several of those of the same size over the years. I notice it has a fixed plate, which is harder to clean than one with a removable plate, especially when filtering something like gold powder and some of the powder goes through the paper and gets trapped in the vac chamber - I used to clean mine out with AR every so often. However, one with a removable plate costs about $500 more and, if you're not very careful, the plates are easily chipped when removing or replacing them.
All in all, if you can get it cheap ($200, say), I would snap it up. Make sure the side-arm, where you attach the hose, is intact - they get broken easily. It looks like its OK, though - click on the photo.
The large plastic buchners I have owned were made by Bel-Art. An 18" costs about $800. The fixed plate (perforated type. I don't like the porous plate type - very hard to clean) seal better but, here again, they are not as easy to clean as the removable plates. Unlike the Coors removable plate, though, the Bel-Art plate goes all the way to the edge and this makes it very difficult to seal the paper. They do sell a special ring to help seal it but its not cheap.
http://www.belart.com/shop/146253518-buchner-funnel-wmedium-fixed-plate-p-146253518.html
Many years ago, a guy I worked for had an all stainless (about 11 guage - 1/8") buchner (about 30" dia) that was only used to filter large amounts of silver chloride that had been dropped out of nitric. It was made in 3 pieces. The bottom table top vac chamber was open top, about 6" high, with a side arm near the top for the vacuum hose. I also think there was a valve near the bottom to drain it. On top of that was placed a plate with about 3/4"-1" holes in it. The plate set on a lip inside the top of the vac chamber. On top of the plate was an oversize piece of very thick spongy filter paper cut from a roll. On top of the paper was a stainless ring for the solution to be filtered, the same diameter as the bottom and about 8-10" high. The whole thing was held together with a series of toggle clamps around the outside. Very easy to clean. The only problem was that, if a vacuum wasn't constantly maintained when there was liquid in the top chamber, the liquid would wick through to the edges of the paper and end up on the floor. That happened to me once (only) and that's what got me to thinking about my wick filter.
I always thought this could be fabricated from thick plastic, probably PP. If I get a chance, I'll make a drawing.
