Getting My BOT!!

[bakerkr]

YES! Will drive down tomorrow to pickup my BOT! Can't wait. Need some advice here. I can handle getting the BOT setup (I hope
), but after that, do I cut the grid and holes for my vac table, then surface my spoilboard? Would love to hear your stories of what you did first, what you wish you would have done, etc. Just want to pick everyone's brain here.

Thanks!
Kevin

[richards]

Which comes first, the chicken or the egg? If your vacuum board sits on top of a layer of plywood like I have on my Alpha, I would level everything as best I could and then surface the vacuum board, and then, after surfacing the vacuum board, I would surface the spoil board (and then resurface the spoil board every time it needs to be resurfaced or whenever a new spoil board is put into service).

If the board beneath the vacuum board is particle board or MDF and if you are certain that you won't clip any bolts that hold the sub-vacuum board in place, then you can probably safely surface the sub-vacuum board.

I may be giving advice that is totally contrary to what others would give, but when I surfaced my table for the first time, I only had to remove 0.015 inch to get everything smooth and flat.

If it makes you feel any more confident, go to the HolzHer website and look as some of their CNC videos. On one of the videos, they state that it will probably be necessary to surface the spoil board several times each day! I thought that resurfacing the spoil board every few weeks was excessive.

-Mike

[gerald_d]

Good luck Kevin! For a first time starter, I would put a plain, cheap table top on first (no vacuum).....till I know that I can drive the moving parts with confidence. We are 5 years down the road and the full vacuum table hasn't happened yet.

[mikejohn]

Kevin
Have a look at this thread (http://www.talkshopbot.com/forum/cgi-bin/discus/show.cgi?tpc=7&post=23267#POST23267), and even the earlier ones on table assembly.
Lots of input there for the complete ignoramus who asked the first question in that link!
.......................Mike

[bob_lofthouse]

Kevin,

I think it depends on what your going to cut with your machine.

We are flat panel processing and cut approx 2mm into the spoil board for each piece.

As we have a vacuum suffiecient for our needs to hold the work down, we have never needed to surface the spoilboard.

We have dropped our spoilboard down from 9mm to 6mm and now to 4mm.

Our support board is 12mm Mdf and 18mm ply for the vacuum/plenum board.

If and when we will replace the plenum I will use 12mm ply for the support board and 12mm ply for the plenum.

Another thing I would change is the cut depth into the vacuum/plenum board. I would now cut the channels 10mm deep and 10mm wide. we have a 10x5 table on which we mainly cut 8x4 sheets, so we use a rubber cord placed in the channels of the plenum board to cut off the suction to unused parts of the vacuum grid.

I hope this all makes sense as its 6.30am here.

[bob_lofthouse]

Further to the above....

There is nothing more upsetting than seeing your Nice new varnished vacuum/plenum cut into by mistake.

I nearly cried the first time...
However I have now come to terms with the fact that it will happen at least once a month due to operator error.

[tuck]

I've been a successful BotHead for almost 4 years and have done so without a vacuum hold-down system. I screw everything down and use spiral down bits. These bits pack the cuttings into the cut groove and hold everything in place. If you're cutting through thin material (1/8" or less) you have to baby sit, but with the $$$ I'm making, I don't mind that. ;-)