Ready Steady Eddy

[EddyCurrent]

Now commited to current idea having ordered 2 of these; http://www.oxfordweldingsuppliesltd....sey-clamp-gh20

This will be accurate, repeatable, easy to work with, the corner being perpendicular to or at right angles to X,Y,Z planes.

[Blackrat]

Them bessey clamps are amazing !!! Never want to use any other clamp after using them ...

[EddyCurrent]

Them bessey clamps are amazing !!! Never want to use any other clamp after using them ...

Thanks, that confirms my thinking.

[Wobblycogs]

You'd be hard pressed to beat Bessey clamps. I've got got some K Body clamps and there's nothing else even close in terms of quality but the price makes your eyes water (although I notice they are doing a sale at the moment). I hope you are going to post a wide selection of pictures of the finished clamping jig. I must admit it crossed my mind to make a similar addition.

[EddyCurrent]

The completed project is here; http://www.mycncuk.com/threads/8243-...5028#post65028

[PAULRO]

Hi Eddy, i'm about to gather the electrics for my build and would like to use your electric schematics design ( or very close to it )if that's o.k with you. i have wired in the past but nothing on this scale. i have a a few queries you might help me with..........1. if the drives are rated for 80 V DC would i get away with an 80 or 70 V DC power supply?(i'm more than likely going to use a 60 V DC like your self. i'm just curious )
2. if i do use a bigger supply will i have to go with a bigger circuit breaker? ( what determines the size of circuit breaker required?)
i'm trying to get to grips with the safety relay because i never had the pleasure to wire one but i would like to have one after reading your blog a few times.

[EddyCurrent]

1. if the drives are rated for 80 V DC would i get away with an 80 or 70 V DC power supply?(i'm more than likely going to use a 60 V DC like your self. i'm just curious )

You could go higher that 60v but it can rise due to back emf from the stepper motors.

2. if i do use a bigger supply will i have to go with a bigger circuit breaker? ( what determines the size of circuit breaker required?)

The circuit breaker size is related to the current drawn by the system. You need to make sure it's the right type otherwise it will trip every time you power up, type C or D
http://www.neweysonline.co.uk/MCBs/Static.raction

i'm trying to get to grips with the safety relay because i never had the pleasure to wire one but i would like to have one after reading your blog a few times.

Ebay is the place to look but first you need to decide this;
1. operating voltage and AC or DC
2. how many contacts you need and are they NO or NC
3. Safety Category of device. If it's for home use then just about any of the devices will be okay.

[JoeHarris]

There's not a lot of progress to report, but thank you kindly for your support.

It took only a few minutes to remove the meniscus using a course file, because there was 10mm each side of the rail it meant there was no need to get it perfectly flat across the whole width. I did run a bead of liquid nails down each side of the epoxy just to give a nice transition onto the metal.
Got the rails on, one support beam painted, 20mm aluminium gantry support bracket fitted and ballnut bracket attached.
Ball screw temporarily installed just to show actual position. Tried to keep rail and ballscrew in same horizontal plane as much as possible.
I had to regrind some drills to make counter boring tools for the cap head screws.

Attachment 11588Attachment 11589Attachment 11590Attachment 11591Attachment 11592

Showing end of beam with rail, epoxy, 6mm internal flat bar to give extra thickness for rail mounting screws, glued it in with Gorilla Glue and worked great.
Attachment 11593

Eddy how did you ensure your x rails were parallel and x and y were 90 degrees to each other??

[Boyan Silyavski]

Eddy how did you ensure your x rails were parallel and x and y were 90 degrees to each other??

Hi Joe, if you remember i explained it here #151 in detail how i did it, if its of any help.

But basically in following order gravity and epoxy did the job in one plane for long rails/y/, gantry legs and using square between them, then for gantry rails/x/. Then 1 gantry rail was mounted and using hardstop/precision cut squared piece of sth/ fixed at same distance to gantry legs plane. Then using dial indicator or hard stop next rail was mounted in parallel.

Now the gantry rails were mounted in parallel to each other and square to legs, was time to square long rails. One rail was mounted within millimeter square to frame. It was straightened using straight edge while tightening. So result was first rail straight and on place. Then crossing with the long straight edge and 2 precision squares, checking every 25cm second rail was mounted. That was the most exhausting job as in my case distance was 1800 between them so very difficult to judge square or not. I started scraping the square against straight edge and unsquaring it left and right, so i wanted to get the feeling when in perfect center/square. Once i felt how it feels i used that feeling to square all.

Then gantry was mounted. Then time for Z. First gantry was squared to long rails. Then using clamps clamped on place. Again the long straight edge cross the long rails below in front of gantry. Using squares between it and z rails, ...


All ball screws were mounted 1 by 1 more or less, screw not tight just to hold a little , so when moved to end they will slide on place. Axis moved by hand to one end. ball screw slides on its place, tighten screws, then repeat at other end. That ensured ball screw alignment to be parallel to rails

[JoeHarris]

Thanks Boyan, and yes that description was useful. My issue like yours is a lack of specialist kit. I was asking eddy as he has built in aluminium. I am ok where the aluminium is being mounted in such a way as to make the most of the cast sides as these are nice and flat. But the edges are not and neither are they square. Also the ends of the extrusion I have is not quite flat/square so it makes squaring the x and y to each other hard to achieve. I think I have resigned myself to needing a surface plate and some blue and just scrape the parts square. It's the only way I can think of doing it without a mill... Getting the long axis rails parallel scares the crap out of me!