[DomB]

Hi all,
When it comes to the day to day use of the hobby type cnc router, what type of machine table hold down arrangement would people prefer.

Here are some ideas.

Unidirectional T slots, leaves the maximum area of the table flat whilst giving areas to fit hold down devices but not always where you need them.

Crossed T slots, much more choices on where to mount clamps but much less flat table area, you always tend to put something right over a t slot, and it falls in so you end up moving it around. They also weaken the stiffness of the table.

If the t slots are precision machined keys can be used on vices for quick set ups for most normal jobs, instead of using a clock.

Grid of tapped holes. Can't slide along like t slots but with slotted clamps some adjustment is possible. Holes tend to get packed with junk and are hard to clean out as they are threaded, If you strip one then it is never going to be as good again even when helicoiled. There is never a hole right where you need it.

Hybrid; a few t slots and a less dense grid of holes between them.

Vacuum table; only useful on some parts.

A table split into sections with a different clamping mechanism on each quarter. Reduces overall clamping area per system, all tend to get in the way of each other.


Any better ideas??
Dom

[ger21]

Vacuum table; only useful on some parts.

You've apparently never used vacuum. No clamps to get in the way. Virtually anything can be clamped with vacuum. And especially with a hobby router, where most everything you cut will be flat to start with.

[DomB]

I'm aiming the machine to do a fair bit of small component ally machining too, blocks with fairly limited vacuum area.

Are vacuum tables popular here? How many of you use one at present. Are there problems using them?

many thanks
Dom

Also what about a coolant ditch around the edge of the table to stop liquids like cutting oil dripping off the edge? Would that waste table space or be a valuable addition.

Rember this post is not really what I am using a machine for, I want to get an idea of what you guys use it for.

Dom

[rustamd]

I think its safe to say that 99% of router users do not use any type flood coolant. no ditch would be needed. I have seen people use some spray coolant but never flood coolant on router. Air/vacuum is probably best option for wood router.

Also the most DIY type of table would be either tapped holes or t nuts under mdf sheet. T slot table can get really expensive. Vacuum table is possible DIY

[Madclicker]

I made my table with t-tracks running the length. It works well and I would do it that way again. Not that expensive. I later made a vacuum table.

There are two memorable cuts in the life of my machine. The first was the first cut under 3 axis power. The second was the first production panel I cut with the vacuum table.

[EKFER]

I checked the 8020 T-Slots and also thought about making a drilled plate but these alternatives are too expensive. Then, I found Rockler.com. They have a 3/4 x 3" x 36" T-Track which gives 3 choices for clamping at 3/4 intervals. At $24.99 for each section (I bought 5 to make a 15" x 36" bed), it turned out to be one third the cost of the other choices. When I received them, I was pleased with the craftmanship, the beautiful blue color and even the packaging. You won't be spending too much time clamping down stuff with these tracks. Note, I'm building my own sliding nuts for the tracks which I will be using by pairing them in the same track opening or by bridge accross track openings. Perhaps this helps.:idea:

[adprinter]

Take a look at the table design I went with, in building my first robot.
It has accommodated everything I have needed to do with it to date. Utilizes 1/2" bolts to secure clamping fixtures, guides, or even drill vises to the table. Not the cheapest option, but not too much more either, if you buy the raw materials and build it yourself. This was the closest construction design to a cast iron table I could come up with. There are very few limits in terms of positioning adjustability of anywhere you need to mount something onto the table surface, and it is very strong!
Hope this helps. -Michael