Customizing Size


Hi all… im looking to build a wilson 2 and have read places mentioning a spreadsheet that lets you plugin custom size bed etc and automatically change the size requirements for Aluminum extrusions, smooth rods etc…

does this mythical beast of a spreadsheet actually exist?
looking for a 300 x 300 x 300 x build.

Lastly the BOM mentions

is that correct?
ive read places that say there are only 2 pieces of 500mm extrusions not 4 as its listed.



It’s in the github repository:

It’s an OpenOffice spreadsheet, so you’ll either need OpenOffice or LibreOffice Calc to open it, or you can import it into Google drive and open it.


Yes there are only 2 of the 500mm extrusions. I must have fat-fingered that somewhere along the way.


Hi hasbridge
Thanks. I tried opening the “.ods” opendoc file in google docs and its saying its corrupted and wont open.
I also tried converting to excel and get the same error.
Can you please confirm if the doc is corrupted or if not maybe its me…

Thanks for the update mjrice… i noted the changes.


Hmm, it works for me in Google Drive. Here’s what I did:

  1. Download the raw .ods file from github:
  2. In Google Drive, click New > File Upload, and select the file
  3. The file should now show up in Google Drive. Double-click to open it, and it should show a preview
  4. At the top of the preview, click the Open button to open the spreadsheet in Google Sheets. This will create a google sheets format copy of the spreadsheet in your drive.


Hi Hasbridge

Thanks that worked perfectly!
I was trying to open directly with google sheets and that did not work.
Importing with Drive did the trick…

The only think i noticed was that the heat bed size did not change but i assume if i want 300x300 i will need a 300x300 bed


Speaking with no practical experience, I think it depends on what you are going to do for a heater and bed. I’m going to use a silicon heater under an aluminum plate topped by glass. The biggest heater I could reasonably get is 350x350, while my build size will be 430x400. The plate should distribute the heat reasonably, I hope. I didn’t want to run multiple smaller heaters, and am using a AC heater also.


How did this build go - how much power did the plate draw and how much space does the fully assembled printer use? What was the build’s total cost as may build this next year but have a strict £300 budget? Finally, how well does it print?


If you are on a tight budget (although £300 seems quite generous) I wouldn’t customise the size. I have a 430430 build area and just trial and error to get things right costs money, I have been using 4mk2 heated plates which draw a fair bit of juice. I have a 350*350mm silicon heated bed coming, and as per the above I trust that the aluminium is conductive enough.

But everything costs more when you go bigger - standard sized PEI sheet is < $20, custom > $60 and so on.


Is PEI much better than glass - in what ways? Please let me know how the silicon heater works with the aluminium as my plan was to use silicon heater + aluminium topped with glass for the heatbed.


You don’t need anything on PEI.

ABS : 90-95c bed and it stick well, lower to 40C and it pop out or easily unstick
PLA : Haven’t tried yet, but I think you don’t even need to warm it up, but anything close to 50c and it’s the same old ez stick/peel
PETG (God of materials) : 70c bed and I stick well (too well!), lower to 40c and it remove easily.
Flex(TPU?) : Stick f**** way too much with heated bed, careful with that one, almost ruined my bed, but cooled down it was removable.


I haven’t bought my PEI yet, I have been using PVA solution on bare aluminium, it works reasonable well but is a PITA. I am trying blue painters tape at the moment and the adhesion is 100 times easier/better than the PVA. I don’t like the rough surface you get on the parts tho!

If PEI is even better then I am sold, problem is that the only local supply I can get will be $130 when he gets it in stock (hopefully later this week)!


I’ve sourced all of the parts for a 300x300x400 build. I can link a google doc with my sources for all the parts, but it got pretty expensive, and I haven’t assembled it yet, so I can’t tell you if they all work together alright. I can post it if anyone is interested, though. If I can offer any advice, it’s to make sure you have plenty time and patience. Also, don’t buy parts until you’re sure you’ve got all the printed parts done, and don’t worry about shipping them quickly. Shipping gets expensive fast.


@babs I am near the end of my 300 x 300 x 250 build and I have found that you will need to make the X extrusions 15mm longer than the parametric parts list shows to get a clear 300mm build width. I think this is due to the rack & pinion, flip down, bed levelling probe design.


@dtbee, Rods too? Or just extrusions?


There is quite a lot of play in the rods but I would lengthen these as well. You can always cut them off but it’s a bummer if they are too short! What are you using for your rods?


@dtbee Um, really expensive ones. I’ll just take the small build area hit… As long as it will still fit together.

As you can see, I was planning on using a smoothieboard…
I’d be looking at over 70 bucks for replacements.
Maybe it would be easier to modify the printed parts with 7.5mm less depth on each side?


It went very well for me. The plate is 800W Alexis, heats up quicker than the hot end. Takes up about 25"x24", not counting the bed overhang when printing. I think the total cost was ~$600, I didn’t keep close track. Big expenses were the heater and aluminum plate. It prints a little slow to keep frame movement down, otherwise great.

My next chore is figure out how to widen the X and Y stance (expand the brackets) for better rigidity for the size, and allow for some bracing. Still need to make a honeycomb sandwich to support the aluminum bed better since it’s so big. My current bed support is sagging, although not quite hitting brackets yet.

I print directly on the aluminum (covered with Elmers glue stick) with no problems.


@dtbee Plugging in the numbers for a 300mm x 300mm x 250mm into the spreadsheet I get:

2020 Extrusions
Vertical frame pieces 450mm
Horizontal frame pieces 430mm
Y axis frame pieces 500mm

M10 Smooth Rods
X-Axis 470mm
Y-Axis 500mm
Z-Axis 370mm

8mm Lead screw 350mm

What were the lengths that you finally used for your build?

Was it 15mm plus on the X-Axis components?