Cost of rails

[kubotaman]

Okay I am thinking about raising my Z axis even higher. I presently have the 12" Z axis but can really only do a total of 13 inches on my 12 inch indexer. I want to do more which I feel the indexer is quite capable of doing. I know I will have to raise my bed so the axis can cut accurately but that is quite simple. I am thinking of purchasing two pieces of 1.5" by 6" by 14' of aluminum side rails and extending my top V rail so I can cut on the Y axis versus the X axis as I now do. The price quoted by ShopBot took me by surprise but was wondering if I have another company as a alternative. Not that I don't want to buy from ShopBot but am curious. Any suggestions out there?

[myxpykalix]

daryl,
instead of raising your rails and cariage i think it would be easier to lower your table. I don't know if you have a prt but here is the table i made.
What i could see you do is create a "trench" in the center of the table or reinforce it somehow so that you could put supports across the top to hold the table that then removes when you want to turn something large.
You could then make a adjustable height table for the indexer to allow you to turn varied diameter of turnings.

[Brady Watson]

I would leave the rails themselves alone. Not sure if you are running a PRT or PRS. The problem with raising the gantry is that you'll lose a lot of stiffness - so it really has to be well thought out with gussets etc.

You can lower the table with a 1.5 or 2 X 6" table side below the one you have now. Crossmembers will bolt to the underside of it.

You can raise the rails by a few inches by placing steel square tubing under the rails.

You can raise the X car with steel tubing (PRT) or taller side plates (PRS).

You can also mess around with mounting the indexer parallel to the Y and make the centerline of the indexer about 1/4" above your max Z depth. Of course this works well for full 3D rotary or unwrapped toolpaths, but it will limit how much -X travel you have in situations where you want to use the indexer to flip a part that may be rectangular etc.

Any way you slice it, it is work - and you have to make sure that your Z is long enough to get full travel. What works for gigantic turnings on the indexer might not work for general cutting, because you may not have enough Z to get all the way down to the table, and you'll lose a LOT of stiffness in the tool.

-B