Small rigid router - Design advise needed

[Clive S]

You could shorten the z belt by moving the motor and turning it the other way up so that the pulley if facing down. ..Clive

[mitchejc]

Thanks Clive, I'll give that a go then I can also move my Y stepper up a little bit to shorten that belt.

[Blackrat]

ja ja wat se jy :P

why even go with belts ? are you going to have a step down ratio ?

i wouldnt bother with the 3rd rail, i think it will just make it harder to clock up ...

what or how are the two bottom rectangle tubes fastened ?

looking good :D

[EddyCurrent]

Looks pretty good but to make life easier later I would draw in your energy chain, drag chain, whatever you call it because it could affect some aspects of the design such as , mounting brackets, length of travel in X direction. Also consider limit switches and homing switches locations.

[mitchejc]

Thanks for the advice EddyCurrent. I will start adding those as I can see it might be an issue with the design as it is now, especially the drag chain running on or behind the gantry.

Looks pretty good but to make life easier later I would draw in your energy chain, drag chain, whatever you call it because it could affect some aspects of the design such as , mounting brackets, length of travel in X direction. Also consider limit switches and homing switches locations.

[Blackrat]

belts aint gonna make it any smoother .... id run a coupler on the two axis' , so much easier and cheaper

im not quite with you on bolting it to a table ? you HAVE to join either sides , no ways you going to cut ally decently if they are seperate from each other, not to mention the nightmare of trying to get them parallel by clamping to a table

[Clive S]

I am no expert but if you follow this forum and take notice of the Master's on here, coupling with belts helps to eliminate resonance which can stop a motor dead in its tracks. Try running a stepper with a loose mounting to see the effect. ..Clive

[mitchejc]

Thanks for the feedback Blackrat. I also like the simplicity of direct drive but quite a few people here believe belt-drive is the better route. I don't know how much better?

The table/base will be a very sturdy steel frame so the two sides are build separately but when bolted down they are connected via the base or am I maybe misunderstanding your question. I guess I can also weld them to the table but that won't be much stronger than having several bolts on each side of both or will it? I thought bolting them would make the alignment easier.

belts aint gonna make it any smoother .... id run a coupler on the two axis' , so much easier and cheaper

im not quite with you on bolting it to a table ? you HAVE to join either sides , no ways you going to cut ally decently if they are seperate from each other, not to mention the nightmare of trying to get them parallel by clamping to a table

[JAZZCNC]

thats not going to work

no ways you gonna bolt it together so that the rails come out within a decent tolerance ....
have a read about epoxy leveling a frame if you havnt already ?

Depends how it's done. Epoxy leveling isn't the be all and end all solution. I've said this many many times but for a good DIY machine you need to build in as many oppertunity's for adjustment as possible and bolting allows plenty of scope for shimming etc to get machine accurate.
If done correctly then it's actually better than epoxy because you can fine tune to very high tolerence.! Only thing is it takes much more time and patience.

belts aint gonna make it any smoother .... id run a coupler on the two axis' , so much easier and cheaper

Actually can make a huge difference esp on all steel machine that's running analog drives with limited resonance handling. This is actually the main reason to use Belts and the ratio option and flexabilty is just a bonus.

Often folks running direct drive don't realise they have resonance problems and just accept that the speeds and performance they are getting is just the max level they can tune to or achive from there motor/drive setup. When often the reality is that the same motors/drives when run on belts and unaffected by resonance will achieve much higher and smoother performance.

[mitchejc]

:-)

No, its just 1:1 ratio. My understanding is that belt drive will make the machine a little smoother. X and Y would be possible to do direct drive but Z will be difficult as I'm trying to keep it as flat as possible.

Not sure but I'm thinking of welding on tabs or a piece of flat bar on both sides that will allow me to bolt it to the table.

ja ja wat se jy :P

why even go with belts ? are you going to have a step down ratio ?

i wouldnt bother with the 3rd rail, i think it will just make it harder to clock up ...

what or how are the two bottom rectangle tubes fastened ?

looking good :D