OpenBuilds Style Build

[WoodKnot]

Hello all -

So the main parts of my build are all arriving today -

C Beam Extrusions, Ball screws and Linear Rails, motors, power supply and some fittings.

The idea is to get all the rails onto the extrusion then fasten it together, so i can then make some templates from 6mm MR MDF for all of my plates.

A few questions in advance -

What is best product to remove all of the excess oil from the rails?

What is the best way to align the rails to the profiles to maintain exact parallel along the length?

My build has twin 20mm linear rails on each axis -

I have loads of squares and clamps to get it all square and true, but little in the way of precision engineering tools.

Thanks

WoodKnot

[A_Camera]

Good luck and enjoy the work.

Q1: I just use a rag, just wipe it off until it feels clean. Normally the carriages come uninstalled. Be careful when you slide them on, so that you don't lose any of the balls.

Q2: I don't think there is a universal "best and only" solution. Depends on the situation, place, distance between and some other things. Use your imagination, test and correct if necessary. Spend as much time as needed, don't hurry because you will regret it.

[WoodKnot]

Good luck and enjoy the work.

Q1: I just use a rag, just wipe it off until it feels clean. Normally the carriages come uninstalled. Be careful when you slide them on, so that you don't lose any of the balls.

Q2: I don't think there is a universal "best and only" solution. Depends on the situation, place, distance between and some other things. Use your imagination, test and correct if necessary. Spend as much time as needed, don't hurry because you will regret it.

Thanks A Camera,

Yes, i thought about cutting some sort of guide then using that as a reference to the width along the length.. I do have some digital callipers to test my self cut guide for accuracy.

Appreciate the comments - I know its going to take me some time!

I did purchase extra lengths of standard extrusion so i can play around with the base to make it more rigid, or perhaps create more height etc.

Like I have said before - the image is there but I am likely to change things as I go along

WoodKnot

[JAZZCNC]

You don't need to worry about aligning the rails to the profile, all you need to worry about is that the rails are parallel to each other and on the same Plane.
If you align the rails to the profiles and the frame or the profiles are not perfectly parallel or bent then you will get binding and other issues.

Likewise same with the Gantry, don't square the gantry to the frame or profiles, square it to the Master rail.

The way to approach it is to select one rail as the Master rail, fasten the master rail down roughly parallel to the profile, then using the most accurate straight edge available fasten it down making sure it's perfectly straight. Now you take all measurements and alignments for things like ball screws from this Master rail.

To parallel the other rail to the Master you rail you can do it several ways.
#1 Leave the rail loose and fit the gantry then using the gantry run the carriages up the rail and tighten down as you go feeling for any tight spots, if any tight spots tweak the rail in that spot.
#2 Use a dial indicator on a beam fixed to a carriage on the Master rail.
#3 Use a parallel bar set to the width you want the rails apart and run up the length of the rail tightening as you go, this is similar to using the gantry.

In all 3 cases, a little fine-tuning might be needed to eliminate any tight spots, but the Key is taking all measurements from the Master rail.

[WoodKnot]

You don't need to worry about aligning the rails to the profile, all you need to worry about is that the rails are parallel to each other and on the same Plane.
If you align the rails to the profiles and the frame or the profiles are not perfectly parallel or bent then you will get binding and other issues.

Likewise same with the Gantry, don't square the gantry to the frame or profiles, square it to the Master rail.

The way to approach it is to select one rail as the Master rail, fasten the master rail down roughly parallel to the profile, then using the most accurate straight edge available fasten it down making sure it's perfectly straight. Now you take all measurements and alignments for things like ball screws from this Master rail.

To parallel the other rail to the Master you rail you can do it several ways.
#1 Leave the rail loose and fit the gantry then using the gantry run the carriages up the rail and tighten down as you go feeling for any tight spots, if any tight spots tweak the rail in that spot.
#2 Use a dial indicator on a beam fixed to a carriage on the Master rail.
#3 Use a parallel bar set to the width you want the rails apart and run up the length of the rail tightening as you go, this is similar to using the gantry.

In all 3 cases, a little fine-tuning might be needed to eliminate any tight spots, but the Key is taking all measurements from the Master rail.

Thanks Jazz, I think I have that!

[WoodKnot]

OK, I think a hugely embarrassing start, everything from the outset seems to be wrong.

Maybe I had made far too many assumptions and that is my fault!

I assumed that the ball screws would be slightly longer than the rails

I assumed that the ballscrew fittings would sit within the C Beam?

It all looks wrong! I don't think I am being a numpty but mine looks nothing like the others, even before I start.

Having parted with the best part of £800.00 just to get started, it's not a good start.

Will post some images in the next post as they are on my phone

WoodKnot

[A_Camera]

OK, I think a hugely embarrassing start, everything from the outset seems to be wrong.

Maybe I had made far too many assumptions and that is my fault!

I assumed that the ball screws would be slightly longer than the rails

I assumed that the ballscrew fittings would sit within the C Beam?

It all looks wrong! I don't think I am being a numpty but mine looks nothing like the others, even before I start.

Having parted with the best part of £800.00 just to get started, it's not a good start.

Will post some images in the next post as they are on my phone

WoodKnot

This is really bad news, I am sorry. I thought you bought 45x90 extrusions, which was discussed elsewhere as far as I can remember. The BF/BK12 fits nicely on those, using 6mm T-nuts, even though the most optimal would be 46mm center distance but the 45mm is fine. Anyway, I missed somewhere in the debate that you did in the end go for something else than 45x90. Hopefully you can use the ones you have now to something else and can buy 45x90 for your project. I normally buy my extrusions from Germany, a company named DOLD Mechatronic. They have good prices and good quality.

Too bad you wasted some money but I guess the lesson learned is to look at technical specs and drawings. While I never spend time on designing a machine in a fancy 3D modelling software, I do spend a lot of time on looking at drawings and specifications before I order something to avoid mistakes like this. Anyway, this is the reality of DIY world. We make mistakes and we learn and hopefully never repeat the same mistakes. Mistakes are made by the professionals also even in the industry, but their DIY is called prototype. The difference is that the prototype never gets sold, so we only see the nice final product, believing that it always looked like that.

Yes, normally the screws are longer than the rails, but with some smart design you can still have the same movement length as the rails allow, assuming the differences in length are not that large.

Regarding the alignment, I assumed you meant parallel alignment between rails and rails, and between rails and screws, plus squaring. As Jazz says, that's what you should spend time on, not aligning the rails with the extrusions. Of course, it helps if the extrusions are also aligned and squared to each other, but the main thing is that all the rails and screws run aligned and are squared to each other.

[WoodKnot]

This is really bad news, I am sorry. I thought you bought 45x90 extrusions, which was discussed elsewhere as far as I can remember. The BF/BK12 fits nicely on those, using 6mm T-nuts, even though the most optimal would be 46mm center distance but the 45mm is fine. Anyway, I missed somewhere in the debate that you did in the end go for something else than 45x90. Hopefully you can use the ones you have now to something else and can buy 45x90 for your project. I normally buy my extrusions from Germany, a company named DOLD Mechatronic. They have good prices and good quality.

Too bad you wasted some money but I guess the lesson learned is to look at technical specs and drawings. While I never spend time on designing a machine in a fancy 3D modelling software, I do spend a lot of time on looking at drawings and specifications before I order something to avoid mistakes like this. Anyway, this is the reality of DIY world. We make mistakes and we learn and hopefully never repeat the same mistakes. Mistakes are made by the professionals also even in the industry, but their DIY is called prototype. The difference is that the prototype never gets sold, so we only see the nice final product, believing that it always looked like that.

Yes, normally the screws are longer than the rails, but with some smart design you can still have the same movement length as the rails allow, assuming the differences in length are not that large.

Regarding the alignment, I assumed you meant parallel alignment between rails and rails, and between rails and screws, plus squaring. As Jazz says, that's what you should spend time on, not aligning the rails with the extrusions. Of course, it helps if the extrusions are also aligned and squared to each other, but the main thing is that all the rails and screws run aligned and are squared to each other.

Thanks A Camera -

Now that i have had chance to get myself orientated this morning - i have checked what everyone else's has used and they are all running 4080!

If I go 45x90, that means all my support extrusions will not fit either!

Most are using much thinner ball screws and also running 12 or 15 rails, where i opted to go 20 to beef it up even more.

I have been looking at the 'carriage' (not sure if that is the correct terminology) that they use on the ball screw to connect to the side plates, this just seems to be a flat plate, nothing like the parts that have come with my ball screws

I need to take some time this evening and re-evaluate the situation.

Thanks

WoodKnot

[AndyUK]

I have been looking at the 'carriage' (not sure if that is the correct terminology) that they use on the ball screw to connect to the side plates, this just seems to be a flat plate, nothing like the parts that have come with my ball screws

Eurgh, the months I spent trying to remember the right terminologies. The moving piece on the ballscrew (a container for a series of ball bearings) is known as the nut. The moving bits on the linear rails are carriages.

[WoodKnot]

Eurgh, the months I spent trying to remember the right terminologies. The moving piece on the ballscrew (a container for a series of ball bearings) is known as the nut. The moving bits on the linear rails are carriages.

Thanks Andy -

Yes, just figured that out!!!!

So................... something has to give!

The least cost option is just to replace the ball screws by the look of it?

I am now trying to figure out which size of thread and flange nut will fit in the 40mm channel.

I intend to keep the 4080 profile and the 20mm linear rails.

I must be able to find something to run in that channel, as everyone else seems to as it is the most common C Beam profile

WoodKnot