I have just purchased a steel/aluminium frame in which I am about to start a build ...pictures attached.
I have just purchased a steel/aluminium frame in which I am about to start a build ...pictures attached.
Drakkn Custom Shop http://www.drakkncustomshop.co.uk
Did a little work on the project
The cost of the frame was £35
will keep adding costs and places where I get the parts.
This is a UK build
Drakkn Custom Shop http://www.drakkncustomshop.co.uk
I have a shopping list for parts
2 carbon steel rods 790mm long
2 carbon steel rods 600mm long
6 flange bearings
8 16mm linear bearings
1 lead screw 12mm o/d 900mm long
1 lead screw 12mm o/d 700mm long
1 lead screw 12mm o/d 350mm long
3 lead screw nuts with flange
3 oldham couplings (lovejoy if you are in USA)
M5 allen bolts cap head ,various lengths
Tin plate 600mm x 100mm
Silver steel for motor mounting rods
2 x 12.7mm x 125mm x 300mm aluminium plate
I must say that the guy who has designed this build (Thanks Harvey) is a really helpful guy.
He is going to do some of the machining for me as I do not have the tools or experience to do some of the jobs.But I think it is going to look like a really strong professional machine.
This is a picture of one of Harveys machines
Drakkn Custom Shop http://www.drakkncustomshop.co.uk
Forgive me if I have jumped in here too quick but this comment is about the design as shown in the pic.
You are going to have trouble driving your X or gantry from one side.
If this is a router or you are pushing any sort of a load at all then racking is going to give you problems for sure.
Also the bearings on the gantry bottom really could do with being spaced a little further apart.
However that is not as much of a concern as only driving the X from one side.
Please don't take this as criticism. Keep us posted with progress.
Greg
Hi
Thanks for your comments - I have seen one of these in action and it appears to perform very well - Having said that once I have it made I will know for sure .And if thats the case then at least I will have a cnc machine that is capable in priniciple of making another one with a better design.
All in all I am a guitar maker not an engineer so I am guided by others in this field . I hope actually it turns out ok.
Will keep you posted
Drakkn Custom Shop http://www.drakkncustomshop.co.uk
Hi Drakkin,
I hope this works out well for you as I know you have been after a cnc machine for quite some time now.
Don’t loose sleep over the fact that the x axis is driven from one side only. It looks like a simple enough mod to add another screw to the over side if needed. I would go with how it is for now you may well find that it works out ok. From your shopping list it looks like your gantry is going to be about 600mm wide so will be down to how hard you intend to push your machine.
About the couplers I use these which are the same as lovejoy and recommend them over Oldham as they are easier to use when it comes to aligning screw and stepper motor. http://rswww.com/cgi-bin/bv/rswww/se...ukie&Nr=avl:uk There not cheap but you only buy them once but they are high quality.
Do you have a supplier for lead screws and will you be machining them yourself?
John
Lead screws are coming from marchant dice (ebay) - he will machine the ends for you - but the guy I got the frame from is only 45 mins drive from home and he will do them for me and some of the other machining bits that I cannot do.
I think he will be selling bits on ebay soon
Regards
Tony
Drakkn Custom Shop http://www.drakkncustomshop.co.uk
I agree with the above poster, you'll almost certainly encounter racking problems driving it from one side. I know first hand, as I had the *exact* same setup on my first machine. Tried everything to get it to work - extra bracing, increasing the distance between the bearings on each side, and so on ... The only solution that worked for me was to add a ball screw to the other side and connect the two screws with a tensioned timing belt - after that, it worked great.
The aluminium for the Y axis gantry sides and back have turned up today - so at least starting to get the rest of the parts together
Drakkn Custom Shop http://www.drakkncustomshop.co.uk
I went to the Model Engineering show in Harrogate on sunday and picked up some silver steel rod 10mm dia x 300mm for the standoff for the stepper motors and some limit switches.
Pictures in the morning
Also dropped in on Harvey who designed the machine (took my aluminium side pieces and he machined the holes for the rods/lead screws etc - pictures in the morning.
Also we both put in a joint order to marchant dice for the leadscrews etc - just to save some carriage as I will be off to see Harvey in a week or so's time.
Drakkn Custom Shop http://www.drakkncustomshop.co.uk
Limit switches 6 for £2.00
6 silver steel rods @ £2.50 each
at the show - will put up suppliers details in the morning
Anyone want a spreadsheet with this info on - please PM me
Drakkn Custom Shop http://www.drakkncustomshop.co.uk
Anyone have any gcode i could use just to test the motors spining
Drakkn Custom Shop http://www.drakkncustomshop.co.uk
If you hit TAB in main screen pendant will pop up and let you jog all axis. To jog full speed hold Shift key. Also you can just hit Load G Code got to C:/Mach3/Gcode and load the famous Roadrunner.tap
I got a controller card and 3 stepper motors from ebay - and I puchased a psu to suit and connected it all up to a dedicated pc - with xp and demo of mach3 installed.
Got the config file for the card and then ran mach 3, 2 of the motors spin but the 3rd does not - no matter which axis it is fitted on - to me that means the motor has a fault - will update further as soon as I can .Unless its not the motor ?? If its not anyone have any ideas.
Drakkn Custom Shop http://www.drakkncustomshop.co.uk
Motor no 3 - I stripped it down and rebuilt it - funny it then worked but was a bit intermittent in movement - suspected a sticky bearing - seems ok for the moment.
Drakkn Custom Shop http://www.drakkncustomshop.co.uk
Hi
Thanks for the reply - It was not completely stripped down - one end of the motor was removed and the moving part was removed and inspected then put back in the casing.Which made it work afterwards - conclusion when turning both the bearings one of them felt a little sticky for a short time .Hope that clarifies things - if by doing this causes the motor to fail then its my inexperience with motors to blame.As they say you live and learn.
Drakkn Custom Shop http://www.drakkncustomshop.co.uk