Seems like to me the heavy use is going to use up any finish---poly being the hardest DIY applied finish on the market.

I think using an easily repaired finish might be the better choice. Varnish does not chip as easily as poly and a varnished surface can be simply sanded and recoated easily.

Sand the table top to get rid of the old poly, clean well-----a rag dampened with paint thinner will do-----and put on the first of three coats of varnish with a good brush. (I like Purdy brand brushes). Follow the varnish manufacturers directions for the subsequent coats.

Then, when the finish needs touching up, simply sand and add one coat of varnish.

I'm wondering what you're using to clean the table. Some common cleaning products -- 409 and Fantastic come to mind - can be awfully hard on many finishes if used frequently.

Thanks handymac, I will be following your directions for the refinish. Jon1270, I think you hit on the problem;I usually just grab the closest cleaner to spray on there; what's the best thing to use that won't soften the finish?

Go for something mild, for regular cleaning. You could make up a bottle of dilute Simple Green to keep nearby, or use a dot of dishsoap and a wet sponge. I'm no chemist so I can't say exactly which ingredients are problematic. I think 409 and Fantastic are both ammonia-based (they have warnings to avoid using them with chlorine bleach), so perhaps that's it. You'll probably do fine if you avoid cleaners that are overkill for the amount of dirt you need to remove.

I have a heavy use table, with poly and it stood up veryw ell to daily washings with 409. I think the fault lies in the table having a residue under the finish. You say the poly is easily scraped off? Sounds to me like there was a residue of something, either stripper or a bit of spray polish or something that wouldn't let the finish adhere.
I would get out the sander and get it down to bare wood and try again. My poly lasted easily 20 years with the table used for daily eating and home work, games etc. I used at least 3 coats and sanded between each.
Linda C

"Seems like to me the heavy use is going to use up any finish---poly being the hardest DIY applied finish on the market."

Behlan's Rock Hard Table Top Varnish is much harder than poly, but a real PITA to apply.
If you use it do not use any other solvent than the recommended.

Behlan's Rock Hard Varnish is a derivitive of old recipes and not as impervious to chemicals as is plasticized polyurethane. It is an old standard and very good, but not as hard as some polyurethanes.

A quote from the article listed below----"This oil based varnish contains natural gum resins that were commonly used to make varnishes in the 19th Century. It has been blended and modified to produce excellent protection while still retaining all the good qualities of varnish like ease of application by brushing and a beautiful amber color."

A quote from a book titled Understanding Wood Finishing written by Bob Flexner, a nationally recognized authority on finishes about polyurethane----Polyurethane was developed in the 1930's and is commonly used as a plastic. Polyurethane is very tough. There are several varieties of polyurethane finish. The polyurethane you see most often in stores is actually am alkyd varnish modified with polyurethane resin, a uralkyd. This type of varnish has become the ,ost popular of the three varnish types because it is the most scratch resistant.

Here is a link that might be useful: Behlans

Flexnor earns a living selling books, not finisheng amd making furniture.
He is very much geared to the mass market.

The nice thing about the Rock Hard varnish is that it can be rubbed out with oil and rottenstone, whereas _no_ poly can receive such treatment satisfactorally. The shape of polyurethane molecules apparently are so interlinked that they cannot shear off cleanly, which is needed to get a hand-rubbed finish.
Casey

Could be so about Bob, but it does not change the facts.

The OP was asking about a hard easily cleaned finish----a hand rubbed, fine furniture finish does not qualify, IMHO.

I personally do not like poly, would rather use varnish or shellac or lacquer. But poly is still the hardest, most scratch resistant easily applied finish ---for the masses.

Rock hard is a very hard finish, much better than any poly I have encountered.
This is not based on reading what it is made from, but by actually using the product in a number of commercial installations including bar surfaces.
It is hard, and takes significant work to rub out.
A rubbed out rock hard finish will easily stand up to residential use.
The drawback is the hardness and the curing time. Like any varnish it takes a while to be dust free, and even longer to finish hardeneing.
If you want the plastic lookl of poly, go for it.
It never looks as good as lacquer or varnish.