Build starting in Huddersfield UK November 2012 **table alterations & long Z axis**
 

Hello everyone,

We are just finishing off adapting our garage to accommodate a CNC machine. We were going to invest in a GreenBull (larger version of Blackfoot plywood machine) but had a last minute change of plan and have decided to build a MechMate. :D

Part of the changes to the garage has been building a pit (2000 x 3600 x 900mm deep) which we hope will allow us to get a long Z axis travel by dropping down through the bed of the table, rather than raising the roof of the garage!

I am currently adapting the plans to suit 3050 x 1525 max sheet size (based on UK plywood availability) which is a 325mm reduction in width on the standard bed and also a reduction of 325mm on the overall machine width in our case. We intend to keep the standard length.

I am also trying to design the table in such a way that the whole table can be lowered into the pit, and so that the bed can be dropped out to the floor so when not in use so we can still get a car in and use the pit in the usual manner!:eek:

We only just switched on to the idea of building a MechMate 2 weeks ago and are hoping to get done by Christmas...

Any advice at this early stage much appreciated!!
Matt

Welcome!
Its amazing what people will come up to maximise real estate usage!
You caught my attention. :D:D
900mm pit is really tight for a MM + the lifting floor.
800mm tall MM is possible (remove the table legs) even 700~750 is possible depending how much Z-axis travel you are willing to sacrifice & how much Z-axis slide you are willing to chop-off.
Can't say much about 100~200mm tall retracted height Lifting floor. Not to say its impossible.

Good luck with your integration design.

Hello Matt,
A lot of design challenges and a tight deadline... sounds good,

Some Ideas.
make the table top just under the floor, 8 cm, and be able to "cover" the pit so you are able to create a flat garage floor.
your y and z are above the floor, but be able to move them to the end of the garage.
when you want to operate the machine, remove the covers and.. ready.
You can walk easily over the machine bed to fix the workpiece. not a bad idea with a large table
pay extra attention to rust protection, in a pit it will be sensitive for rust.
I placed a de humidifier to get the moisture down in my basement (80-90% humidity) place a blower in the pit to get air circulation
pay some attention to protect your guidings, they will be sensitive for damaging when you can walk over them.
I made some covers from wood during my building to protect the guidings

good luck and get some sleep when you get tired

long z axis.
I have a long z axis with linear guiding and ball screw. motor on top.
When my machine moves fast and stops, it's shakes, I can not see it in cutting quality, but when i place my hand on it I can feel it....
I am planning to make a shorter Z axis, travel 20 cm with linear guiding and ball bearings. My parts are already laying around. the weight which needs to be moved by the motor is 23 kg. I still doing this without compensation gas spring, but I had to slow down the speed, otherwise my motor is stolling