Wasteboard that deals with different materials

(Stuart) #1

Hi all,

Just wondering how you guys and ladies deal with machining different materials on your Shapeokos? I have an XXL with a 1" ply base, with t-slots and MDF strips that have been trammed. This is absolutely ideal for timber jobs, very rigid with the ability to cut into the MDF and re-tram as required.

The issue is I’ve been doing some aluminium work recently which has resulted in wd40 in the MDF, which softens it and makes it expand a bit.
And an all metal wasteboard doesn’t allow for cutting through on the timber jobs…

Has anyone found a good solution to this?

(William Adams) #2

For a while I had an HDPE cutting board with threaded inserts in it which seemed a reasonable work-around.

For a metal bed, my solution for cutting anything on it would be to add a suitable spoilboard under my stock, hardboard or Masonite for wood, some inexpensive plastic for plastic, or a sheet of aluminum scrap for metal.

(Neil Ferreri) #3

I’m not convinced WD-40 does much more than make a mess. On my last aluminum job, I babysat it with a can of compressed air to evacuate chips and cool things down. My eventual solution will be a mister with denatured alcohol and air. The alcohol will evaporate quickly and take more heat with it.

(Stuart) #4

@WillAdams HDPE looks like a good option, I have looked at making a whole wasteboard out of it but the cost for something stable was quite prohibitive in Australia. Though if I am just putting strips between the T-slot that will reduce.

@neilferreri My recent experience kind of lines up with your comment, though in my last aluminium job i had a few times that I got a severe chatter/vibration, a squirt of wd40 stopped it immediately, though it was out of an aerosol can through a directed tube, which may have had the same effect as your can of compressed air… maybe some more research to be done for me…

Maybe 1/2" steel with 1" thick HDPE strips between the T-slots, with a recessed aluminium plate in the center to use for aluminium plate jobs that aren’t plate material

(Luke) #5

I just bought an almost XXL size of ali for this purpose yesterday. 880x1000x12mm cost me £150. I think wholesale was around £100 Ages back I upgraded my shapeoko 3 to full ali bed. I’m now doing this to my beaver pro for the reasons you mention above.

I plan to use my machine to mill the holes then had tap them this time. I’m also planning a number of jigs around this, such as a vice holder.

Using HPDP was my backup.

(Stuart) #6

Yeah I had an original SO3 with an aluminium plate and it was rock solid, until this week I couldn’t find Aly at a reasonable price, which put me off doing the XXL.

I like the idea of a vice, and/or an aluminium fixture plate. This is something I just drew up, which I think would allow doing timber jobs with a sacrificial wasteboard and flexible clamping options, but also have a rigid aluminium fixture plate mounted to the steel/aluminium baseboard. Blue is HDPE, red is T-slot.

maybe wouldn’t work, but i’m throwing ideas around haha

(Csaba Horváth) #7

I was using laminated fibreboard with threaded inserts for the same purpose. The laminated plastic layer was preventing the lubricants to penetrate and I also sealed the holes around the threaded inserts with silicon based rubber. It was OK for a while than I replaced the whole base structure with 40X80 aluminium extrusions which is way much better for both rigidity and work holding. Sometimes I use a layer of MDF or some laminated wood on top of the extrusions if the work requires but I am in the process of designing my own pallet system to add even more flexibility.
I am also against using WD-40 from a sprayer! I use alcohol mist instead which has numerous advantages.

(Stuart) #8

I like the idea of using aluminium extrusions to replace the base structure did you do anyting to get them as square to the gantry as possible? i.e shimming the extrusions or re-tramming the gantries? maybe bolting thin aluminium strips to the top of the extrusions the size of the cutting area, so they can be skimmed/machined flat would be a good way to go.

Yeah I think I will stop with the WD40 use and get a compressor and blower set up, and give the denatured alcohol a go if I have any issues

(Csaba Horváth) #9

First, I connected the extrusions with two piece of 40X80/3 U shaped hard aluminium extrusions on the bottom of the machine.
Secondly, instead of using the stock steel frame I made my own pieces to connect the extrusion bed with the rails. I used 60x20 flat bars and made them 130 long. I should have made these a bit longer IOT use a good quality precision vise later…:neutral_face:

Then I messed up enlarging the M5 threads to M6. (Yes I have predrilled :slight_smile:

Than I assembled the whole thing and ended up with a thing that was lacking the usual 3 things, parallel, square and perpendicular…

Unfortunately the rails were cut inaccurately. None of the four end were square and all were differently inaccurate.

Than I tried adjusting and shimming all corners. First I picked random points along the rails to lift and tap it to position but that did not work.

Than I started from one corner and work my way around with wedging the legs into the desired position with a piece of scrap MDF, which worked really well. I was checking the height and perpendicularity continuously.

Did the same process with my wife’s makeup mirror on the backside.

In the end I confirmed parallelism with “closing a circuit method” (see the red LED in the corner).

The machine is still not perfect but close enough for what I use it for at the moment. I usually make soft yaws anyway which solves most of the leftover inaccuracies. The next thing I am planning is to make a piece that helps tramming. I have already seen the CAD of that on the forum)

Extruded Aluminium Base (stock MDF base replacement)
(system) closed #10

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