Simple Rigid Steel Desktop Router 900x600x200

[Lachlan]

Well after perusing the idea of a fixed gantry style router, I just couldn't bring myself to build something that lost so much cutting area for its size. So this will have a moving gantry. Please comment on my design as constructive criticism is most welcome!

I just couldn't bear to wait any longer so I have already built the base I know this was risky and stupid but I just had to do something and I was sick of dithering. I am also still coming to terms with Solidworks so modeling is still painful for me at times (most times).

This router will be used for aluminium and mdf so needs to be rigid. I am building it out of 50x50x5 which after fabricating it, surely must be plenty strong enough for the job at hand. I note that many others on this forum use much, much larger steel box section but I need this to be movable and light enough to lift. The router design will be loosely built around Boyan Silyavski's excellent example though with a smaller cutting area and smaller box section.

This build will take a long time as I have only steel at the moment and I will need to save in order to buy all the necessary components.
So far i have settled on
425oz steppers
1605 z axis
1610 x, y axis
20mm linear profile rail x,y,z
htd 15mm belt and pulley (20 tooth)
drivers and BOB not sure

Base model


Base being built







Finished base


Some notes on building the base:
Absolutely need a straight edge for alignment
Tack in the middle and then weld both sides after confirming it is straight and level.
Even when welding short beads the welds have the potential to warp and move the steel members.
Only use F clamps and G clamps. Notice in one of the pictures i have a blue quick clamp. Don't use these! They have their place, but not with this project, must be rigidly held in place.
Building to be as precise as I can is slow! Its at least 3 times slower than gate building so take your time check weld check again, check in the other direction, find out its out by a 1mm, swear, grind the tack, reposition,clamp, tack again and so on. The beauty of a project like this is if you are not good at welding to start with you will be by the end because there are soo many welds to do.

The left front upright member was 2mm out, at the top rail, after the final weld, (this is before I added the flatbar bracing) even with constant checking, so I thought that I would use an old trick and got the thickest rope I could find and wound it around the top of the upright and then diagonally down to the base. then proceeded to twist the rope with a steel bar after all it was only 2mm that i needed. Well the rope SNAPPED!!! The steel had not moved.

Time to move it up a gear! Next,I got the tractor chain and did the same thing only with 100mm box section (1 metre long) rather than the 60cm long steel bar, but i couldn't apply enough force to move it. So finally I used a crowbar through the box section and only then was I able to attain the necessary leverage to pull the upright member into perfect alignment.This activity was all on the least braced section of the frame. Surely, the frame will be rigid enough.

My next installment will model the router's gantry, though this is far more complex to model so may take me a while. Thanks for dropping by!

[routercnc]

Looking good. You are going down a tried and trusted route with this design so far so should be ok.

p.s. As I write this it is a cold, dark, rainy morning - jealous of your views and weather!

[Lachlan]

Looking good. You are going down a tried and trusted route with this design so far so should be ok.

p.s. As I write this it is a cold, dark, rainy morning - jealous of your views and weather!

Thanks mate, I spent 12 months in England many years ago. The people were heaps of fun but I don't miss the constant drizzle and gloom.

I have 2 different ideas in mind. Can people please comment on which they think is better or if I have completely dropped the ball suggest a better design altogether.

Gantry Frame Design 1

Pros
Seems to be a more conventional design. Maybe better Braced then alternative
Cons
Heavier 23kg

• Spindle will be slightly in front of leading edge of front gantry y axis linear rail block. Could lengthen gantry from 250mm to 300mm to fix this or could reduce box section from 200x100x4 to 200x50x4 don't really like either option.
• More chance of warp due to more welding
• More complex to work with, holes and relief cuts needed to fit necessary components in back of gantry.

Gantry Frame Design 2

Pros

• simpler to build
• Spindle is within leading edge of linear guide maybe more stable (spindle not drawn just calculated)
• lighter (20kg) just frame as shown
• Easier to add componentry to back of gantry

Cons

• ? Maybe less rigid due to having no back bracing on the gantry.
• Fixing the 2 y axis linear guides to the back of the gantry will be more difficult

So which broad design do you think is better and why? Also is weight going to be a problem? Maybe another 30 ish kg to add to gantry with steppers, guides, z axis etc. Will 425oz steppers be too weak?
Thanks for any advice given!

[sinnsvak]

Hi, nice design, I think you are off to a great start. Will be following your progress :)


I would go with option 2, because it will be a little easier, but equal in strength. The center of gravity on the blocks will also be better.