[Goemon]

I should have mentioned that I already bought a 1.5" x 10" x 36" "precision flat cast aluminum plate" for this, so any t-slot table could be mounted on top of that. The cast aluminum plates arrive with minimum flatness tolerances of better than .005" out of the box. All of my rails are mounted on them too.

I was going to just bolt my aluminum mold blanks directly to the cast plate but I am having second thoughts about that as a long term option. Having t-slot tracks seems like a good way to reduce set-up time.


There are other options for a little more money (but still affordable). E.g. I could bolt a bunch of t-tracks to my cast plate and fill in the gaps with resin. I could buy a an old 36" Bridgeport table (although I don't know how flat they are). An eBay seller is offering new Haas VF2 aluminum sub plates for less than $400.


Those aluminum CNC T-slot tables are just one of the cheaper off the shelf options but if they aren't good enough to use out of the box then I don't want one. If I have to spend time hand scraping then I would rather build my own out of the same carbon fiber epoxy granite mix as the gantry and base.


I was hoping that someone here might have one of these eBay CNC tables and be able to tell me if they are any good. Hard to tell much from the pics....

[Arjay]

I should have mentioned that I already bought a 1.5" x 10" x 36" "precision flat cast aluminum plate" for this, so any t-slot table could be mounted on top of that. The cast aluminum plates arrive with minimum flatness tolerances of better than .005" out of the box. All of my rails are mounted on them too.

I was going to just bolt my aluminum mold blanks directly to the cast plate but I am having second thoughts about that as a long term option. Having t-slot tracks seems like a good way to reduce set-up time.


There are other options for a little more money (but still affordable). E.g. I could bolt a bunch of t-tracks to my cast plate and fill in the gaps with resin. I could buy a an old 36" Bridgeport table (although I don't know how flat they are). An eBay seller is offering new Haas VF2 aluminum sub plates for less than $400.


Those aluminum CNC T-slot tables are just one of the cheaper off the shelf options but if they aren't good enough to use out of the box then I don't want one. If I have to spend time hand scraping then I would rather build my own out of the same carbon fiber epoxy granite mix as the gantry and base.


I was hoping that someone here might have one of these eBay CNC tables and be able to tell me if they are any good. Hard to tell much from the pics....

Instead of hand scraping, can you just bolt it up and mill it with the router?

[Goemon]

Instead of hand scraping, can you just bolt it up and mill it with the router?

No. Milling and routing doesn't produce a precision flat surface. Additional processing is required and hand scraping is the most common method for the diy metal worker. It's not the hardest thing in the world but..... after briefly testing my hand scraper, I found the process to be sufficiently upsetting that I want to avoid doing it ever again if possible. I've had arthritis in my hands since my early 20's so I hate jobs like that.

I went to the expense of buying precision flat cast plates for all of my mounting surfaces and investing in quality leveling resin for the epoxy granite portion of my base to avoid scraping. after going to that much expense, I want any moving table I buy to arrive ready to use or there is no point buying off the shelf.

Luckily for me (and everyone else here), there are plenty of options for low cost, off the shelf, precision flat surfaces. I just didn't know if those ebay CNC tables were in that category.