First Build - Yet Another Alu Profile Router - 900 x 800

[JAZZCNC]

Cheers for that Jazz

It's stuff like this where years of experience really show. It all looked good (to me) on my plan but the practicalities such as being able to access screws or adjust alignment etc just don't become apparent (again, to me) on a model. I would have been stuck into the build before having one of those "d'oh!" moments.

It's common for the little details to get overlooked and it's the little details that can make a big difference to how the machine performs and ease of maintenance etc.

I model all the major mechanical components individually in CAD right down to the exact mm and with every hole for bolts etc in their correct locations. Then I build sub-assemblies with the components ie: Z-axis, Gantry, Ballscrews with end bearings and ball-nut mount, this lets me check for clashes with bolts, etc.
Then finally I build a full working assembly with the sub-assemblies all mated together accurately. This way I can check every detail and catch if any interference or if access is restricted etc. You'll be surprised just how easy it is to miss quite obvious details that would be major problem after parts are made.

My personal opinion is that making mock-up parts from MDF etc is a waste of time and provided you are accurate with the cad models then it's not required and defeats the purpose of CAD. Every machine I build is done solely in CAD with each part machined straight from the model and they fit together perfectly every time. (Unless I screw up the machining which never happens.!. .Honest.!!)

However for those who don't have good CAD skills or use lower-level packages that don't allow mating and assemblies etc then I agree it's a good and safe way to work.

The best advice I can give is to build in as much adjustment as possible and pay close attention to bolt hole locations/access to prevent clashes. Think about the little details right at the start like Limit switch locations, Energy chain mounting and paths, Cable routing and access to grease nipples, etc.

Break the machine down into segments and think about how each segment interacts with the next. ie: Z-axis and how it mounts to moving axis on the gantry and how the Energy chain runs along gantry and mounts to moving access does it clash with ball-screws or motors or limit SW etc when moving.?
These little details can be a right ball-ache if left until the machine is built only to find out there is no way to avoid clashing. Often the difference between something fitting or not is only mm's and can completely screw the job up or cause major part remake or big compromises on design.

The extra time in CAD is well worth the time and frustration it can save, not to mention expense if screw up big.!

[Kitwn]

However for those who don't have good CAD skills or use lower-level packages that don't allow mating and assemblies etc then I agree it's a good and safe way to work.

This probably applies to most of your readers.

MDF can be the old man's CAD. Perhaps we need a new acronym? MAD..... Model Aided Design

Either method will help you avoid creating a TURD... Totally Unbuildable Router Design