drieslaas
03-04-2008, 02:14 AM
Well, after three years I'm there. The little bee in my bonnet is eventually working. And as all works in progress, it will probably reach a more advanced stage of completion for the next three years!!!
I suppose that it was slightly obtuse to start with a fairly large machine as an initial build, but now when a lay down a full sheet of plywood, I'm actually happy that I was audacious enough.The best bit is that I have a full datapack to recreate the machine easily.
The concept is a simple gantry type machine, with a tubular steel structure, rack and pinion drives on X and Y, Geckodrives 203V.
I run the CAM part from Alibre, very happy with that so far, except for a few little niggles.
The only deviation from normal ( I think ) is that I drive both ends of the gantry and the y carriage with a master and slave stepper. This eliminates the need to make the structure as stiff, and so far it works. (it is now a simply laid up beam instead of a cantilever)
Another slight deviation is the fact that the rails are lengths of angle iron, nice thick wall section, on which a set of grooved rollers locate.
All steel plates are lasercut, there's actually very little work to do assembling the machine when you do it this way. Finish is a simple Hammertone paint spray-finish. I call this barecoating: barely coated on bare steel.... The next one will be much better.
Chronologically the project took three years, although a mate with a better memory tells me I've been faffing about this fifteen years ago.
Direct time was probably in the region of eight weeks, design and cad modeling included.
Initial mods include a reduction drive on X and Y to take the stepper to a more optimum power delivery speed range.
Spindle motor will need attention, at the moment it is an ELU router with 1/4" collet, which becomes a severe limitation.
Will post some pics.
One of the largest practical issues was finding stuff that would keep the machine in budget, which was practically non-existent. And some of the things in South Africa was hard to get. Necessity is the mother of invention, as they say, and there is luckily a streak of Viking perseverance which worked overtime on this job. Some would say stupidity, but I'm too busy playing with my new toy to worry about that......
I suppose that it was slightly obtuse to start with a fairly large machine as an initial build, but now when a lay down a full sheet of plywood, I'm actually happy that I was audacious enough.The best bit is that I have a full datapack to recreate the machine easily.
The concept is a simple gantry type machine, with a tubular steel structure, rack and pinion drives on X and Y, Geckodrives 203V.
I run the CAM part from Alibre, very happy with that so far, except for a few little niggles.
The only deviation from normal ( I think ) is that I drive both ends of the gantry and the y carriage with a master and slave stepper. This eliminates the need to make the structure as stiff, and so far it works. (it is now a simply laid up beam instead of a cantilever)
Another slight deviation is the fact that the rails are lengths of angle iron, nice thick wall section, on which a set of grooved rollers locate.
All steel plates are lasercut, there's actually very little work to do assembling the machine when you do it this way. Finish is a simple Hammertone paint spray-finish. I call this barecoating: barely coated on bare steel.... The next one will be much better.
Chronologically the project took three years, although a mate with a better memory tells me I've been faffing about this fifteen years ago.
Direct time was probably in the region of eight weeks, design and cad modeling included.
Initial mods include a reduction drive on X and Y to take the stepper to a more optimum power delivery speed range.
Spindle motor will need attention, at the moment it is an ELU router with 1/4" collet, which becomes a severe limitation.
Will post some pics.
One of the largest practical issues was finding stuff that would keep the machine in budget, which was practically non-existent. And some of the things in South Africa was hard to get. Necessity is the mother of invention, as they say, and there is luckily a streak of Viking perseverance which worked overtime on this job. Some would say stupidity, but I'm too busy playing with my new toy to worry about that......