My Rapide Lite 312

[clayton]

Hi All,

It's been a while since I've been around, but all my stuff came in and I finally got around to expanding the print size of my RL200.

It's now 312mm on the y-axis.

Total cost was about $100.

About an half hour of fabrication time, and 45 minutes of install. Mod to firmware to allow 312mm in config.

I could't get the photos to upload, so I tried them as attachments - will upload a video at some point too...



Steps Converting your Rapide Lite 200 to a 312mm bed

You could try any size. I think the 312 mm works well as there is a heated bed available at a reasonable price and the 8mm rails seem to hold up to the size.

It may be too detailed for you, but better safe than sorry :-) It seems like a lot of steps, but if you have the extrusion pre-cut to size and the some basic tools ( I used a drill, a hacksaw, a digital caliper and a belt sander), you should be able to get this done in an hour or so. I can't seem to post photos inline, but I will add them if I can figure it out.

Bill of Materials – cost +/- $100 USD

o 2 x 3030 T-Slot Extrusion (30mm per side and 395mm long)
o 1 x GT2 drive belt 1000mm
o 6 x M3 20mm hex bolts
o 2 x 8mm by 400MM Linear rail (ebay: $20)
o 2 x 320mm angle aluminum stock ($4ish)
o 1 x 200 X 300mm heated bed (actual dimensions 214X314mm) from reprap.me ($20ish)
o 1 x Aluminum plate cut to size (.125 in or similar)
o Some wire to extend the heated bed and thermo reach

Procedure:

1. Do all the safe stuff - Unplug all the things – discharge your static - you know the things
2. Remove your heated bed
3. Detach thermistor and keep for later
4. Undo bolt securing Y-belt bracket to bed carriage
5. Loosen linear rail collars
6. Remove belt idler pulley from front end plate
7. Remove front end plate
8. Pull out 8mm linear rails, keep rail collars for later
9. Slide bed carriage out
10. Remove belt from Y-belt bracket
11. Remove back end plates let the back side with stepper motor hang
12. Cut the T-slot extrusion to 395mm if not pre-cut, they have to be 5mm shorter than the rods so they will seat in the holes on the end caps
13. Tap the ends of the extrusion for M8 bolts – you will reuse the original bolts
14. Drill holes (1/8in – 3mm) in aluminum angle stock to match the bed bolt holes in the bed carriage
15. Drill holes in aluminum plate to match heated bed
16. Drill holes in aluminum angle stock match holes in heated bed and aluminum plate
17. Secure aluminum angle stock to bed carriage with M3 5mm bolts and thread locker (Loctite or similar)
18. Test to ensure heat bed, angle stock and aluminum plate align
19. Remove bottom cover of RL200
20. Remove one side of original t-slot extrusion by removing bolts from below and bolts from side of the z-bracket
21. Slide original extrusion out
22. Slide new 395mm extrusion in – I used silicon lubricant before as you will have to do some repositioning after you have the other side in to ensure it’s square
23. Ensure that the extrusion is centred by measuring both ends against the lower frame
24. Repeat steps 20-22 for the other side
25. Measure to ensure that both sides are equal and that the Z-Bracket is centred on them
26. Reattach the back plate with stepper motor
27. Slide 400 mm linear rails through and seat in holes
28. Slide bed carriage with aluminum extensions onto the rails
29. Reattach front aluminum plate
30. Slide carriage to the back to get it out of the way
31. Fit belt for size – I wrapped it around the stepper motor and over the front idle pulley - then pulled it tight – marked the spot and then cut it.
32. Loosen the bolts on the front idler puller to give the belt some slack
33. Attach the belt to the Y-belt bracket after threading through idler pulley
34. Slip it over the Stepper gear, put the tensioner on and then tighten the idler pulley
35. Attach the Y-belt holder to the bed carriage
36. Test it all moves smoothly – if it doesn’t your extruder rails may be out of square
37. Route your heat bed and thermistor cables - wire them up
38. Slide bed carriage to the front, use M3 20mm bolts from below into holes in aluminum angle stock, then secure from above with M3 locknut or thread locker – then add springs, then heat bed and aluminum plate – use M3 wingnut (not sure if this is a thing) or M3 bolt (as I’m using)
39. Go to your config file in Marlin and change the section for Y_Max_POS from 200 to 312.
40. Change your #define DEFAULT_AXIS_STEPS_PER_UNIT back to 160 for the GT2 belt if you set it to 157 for the MXL
41. Print all the things, but bigger!

[clayton]

Here is a quick youtube video -

[bolsoncerrado]

OMG that's fantastic! The degree of hacks we're coming up with is amazing

Can't wait to add this to the 200XL so it will turn up 20x31x40! wohoo!

[JonatanJacobsson]

Wow. Thats a fantastic mod. Doesnt seem that difficult either
Amazing work. Will look into it my self.

On this setup you could also counter warping in the Y-axis by installing another set of bedscrews at the center

[bolsoncerrado]

Wdy mean another set of bedscrews on the center Jonatan?

[milstream]

Nicely done Clayton!

Was that 20-2020 or 30-3030? 80/20 extrusion?

[JonatanJacobsson]

To counter warping of the alu-bed, Right now the setup is using one screw in each corner. You can with this setup that Clayton has - drill additional holes on the side between the two existing.

But from what i can tell from the images - he already has drilled those holes

[bolsoncerrado]

Time for a stepbystep instructable howto, clayton

[clayton]

I'll get around to the step-by-step in the next 48 hours or so - to answer a few questions now:

- Yes, I drilled the mid length holes, but so far I don't notice any warpage - I used 1/8" aluminum 6011T6 sheet - will consider it if I notice a warp.

- It is the 20/20 - that is just 20mm X 20mm square - it's the same as the link I posted to Amazon. you can find it locally as well and they will generally cut to suit. This would be easier than what I did, with a hacksaw and then sanding it with a beltsander to make it level.

- I tapped the metal rails with a M3 tap, but in V2 - I am going to invert the M3 bolts, use a lock-nut and use wing nuts on the top of the bed to help level it.

It prints noticably better now - the old rails were a little warped and it moves more smoothly. Also there is no slop now in the bolt holding the bed - I found they did not seat well on the original bed.

[bolsoncerrado]

I'll get around to the step-by-step in the next 48 hours or so - to answer a few questions now:
- I tapped the metal rails with a M3 tap, but in V2 - I am going to invert the M3 bolts, use a lock-nut and use wing nuts on the top of the bed to help level it.

-Also there is no slop now in the bolt holding the bed...I found they did not seat well on the original bed.

What are those two steps about? Not sure if I understood them well?