building a repstrap
mechanically unsound but completed
just need the electronics, extuder, hot bed, etc

Looking good!

It's all metal except the white plastic board

Main issues I can think of are:
1. Z axis is driven only on one side and connected with 3mm aluminium
2. Z rails have no bracing support in the x direction, at least this is fixable
3. Backlash is probably excessive, as it is chain driven.
4. Stepper motors are NEMA24 31kg/cm, just dont crash it
5. None of the nuts have spring washer.
6. Can't see the Y stepper motor mount lasting too long
7. One of the z axis rails mounts is not square, fixed this with washers

Good points
1. It's all made from left over or scrap metal or salvaged from a previous machine. Meaning I had already paid for it.
2. Fix the above problems and itll cut aluminium.
3. All axis move freely

Now I need to buy a hotbed, limit switches, controller board, power supply and stepper drivers. I already have an extruder.
I was thinking an all-in-one board like the RUMBA,

Nice work.

chris... Wrote:
> Main issues I can think of are:
> 1. Z axis is driven only on one side and connected
> with 3mm aluminium

Do what the old Wades Mendel did and drive both sides using one motor and a belt (or chain in your case) between the Z rods.

> 2. Z rails have no bracing support in the x
> direction, at least this is fixable
> 3. Backlash is probably excessive, as it is chain
> driven.

Keep the chain tight and at least it should get you going. Probably enough to make any bits you might need.

> 4. Stepper motors are NEMA24 31kg/cm, just dont
> crash it
> 5. None of the nuts have spring washer.

If necessary, put a second nut on the back of the existing ones. and tighten the nuts to each other, at least till you get some spring washers.

> 6. Can't see the Y stepper motor mount lasting too
> long

Make another like it and mount it underneath perhaps? Most motors have screw mount holes on both ends.

> 7. One of the z axis rails mounts is not square,
> fixed this with washers
>
> Good points
> 1. It's all made from left over or scrap metal or
> salvaged from a previous machine. Meaning I had
> already paid for it.
> 2. Fix the above problems and itll cut aluminium.
> 3. All axis move freely
>
> Now I need to buy a hotbed, limit switches,
> controller board, power supply and stepper
> drivers. I already have an extruder.
> I was thinking an all-in-one board like the RUMBA,

Sounds like a reasonable choice.

Anyway, welcome! Hope to see you printing soon enough.

PS: What part of Melb/Vic are you in? I'm in Caulfield, and the local hackerspace (where we hold a 3D printing night, twice a month on the 1st and 3rd Monday of the month) is in Hawthorn. The hackerspace is called HackMelbourne. If you're ever nearby, feel free to drop in and say hello.

I'll need to construct a fair few things to drive both sides, adding a second stepper motor maybe easier. I might just counter balance it for the moment.

I'll check backlash once its running and see what its like

y motor has no mount holes at the bottom

The machine should be good enough to print plastic parts to build a better machine

I just assembled the Crap extruder I ordered.
Its a cheap garbage knock-off of the MK7 stepstruder