Hi guy's I had an Ox when Mark made those first 2 videos back in the day but unfortunately, my wife took it apart after I was in the hospital with my second heart attack and locked it away so I would live longer (or so she thought). But now I have a new lease of life after a by-pass op and wanted to get another hobby. I won't be exhuming the OX, but I was wondering if I had enough 'OX' parts to build a Mini Mill instead. I see the one on the 'Build' page uses 'C' channels, but is it possible to build one with 20X80 instead. I have everything else, Nemas, Scew rods, brackets, Base plates, wheels and a ton of fixings that I've accumulated over the years I'd be grateful if anyone has knocked up something similar to a 'Mini Mill' with the above assortment of parts to let me know how they put it together. All I want is something 'Desktop size' so I can mill some medals for my Grandkids under 11's football team. (That should keep 'She who must be obeyed happy). Thanks a lot.
If you have a decent stock of 20x40s you can easily knock out some C-beams for this. 20x80s would readily work for the vertical portion of the framing. It would be best though if you could provide us a generalized inventory of what you have to work with. Not all OXes were built the same.
Hi Rick Thanks for replying. I'll do a list of what I have in the cupboard over the weekend and paste it up here. Thanks.
I dug out the original list I had when I constructed the OX and I've amended it to list what I've accumulated over the years. It's a bit lengthy so I hope the mods don't mind me attaching it. Thanks.
While it is fairly easy to mock up C-beams using 20x40 members... I'm really not sure it's worth the effort in your case if you are trying to keep stress levels to a minimum. Getting a perfect match and having it perfectly square takes quite an effort and the 3 pieces of C-beam you need are such a minimal expense just buy what you need rather than fight with what you have. Beyond that, you have a substantial amount of what you need already but you will need a few more parts. The most significant are 3x C-Beam XL Gantry Plate and 6x C-Beam End Mount - Ooznest | Kits, Parts & Supplies. The C-beams you will need would be 250mm for the Z-axis, 400mm for the Y-axis, and whatever suits your needs for the X-axis (350-400mm makes for a pretty usable axis). If you don't already have a proper spindle mount you'll probably want to pick one up. I'll leave it to you to figure out what you have to work with and what you'll need beyond that. As for the remainder of the build you should be able to transfer most of the screws, nuts, wheels, clips, (etc.) you already have and which are typically the most expensive part of the build. Below is a basic concept. The main column is just (3) 250mm pieces of 20x80 epoxied together with another (3) epoxied 110mm pieces of 20x80 used as the spacer to hold the Z-azis actuator assembly. With the epoxied layers you'll want to drill and run some long screws through the layers just to make sure if the epoxy ever pops the system won't pull apart and crash down on you.
Hello Rick Are you sure its 3 C-Beam XL Gantry Plates and 6 C-Beam End Mounts seemed rath a lot? The idea of 3 epoxied 20x80 pieces to make up a C beam are somewhat daunting, to say the least, and better got from OOZnest instead. I've got 2 spindle mounts fitted with inserts to take a Makita RT0700C Router which makes it a snug fit. Thanks.
Here is another concept mounting the Ox Z-axis plate to a regular MiniMill framework. It reduces the XL gantry plates to 2 and the end mounts to 4 but that's about as far down as you can take it. You're converting the X and Y axes to screws and you need the receiver plates to accommodate it. The framing uses a 250mm C-beam for the column and 110mm pieces of C-beam and 20x80 as the spacers. Sketchup file attached.
You must think I'm an old miser, but 'She who must be obeyed' thinks I already squandered the grandkids inheritance on the first OX and all the bits and pieces that went with it. If you recomend 3 C-Beam XL Gantry Plates and 6 C-Beam End Mounts then I'll get those. By the way, I found a video 'Openbuilds MiniMill' with a young guy that would look more at home working out with Dwane 'The Rock' Johnson than building a MiniMill. Is that what my build will look like once it's completed. Thanks.
Hey Rick I've ordered what you suggested but noticed there are two 'Jog Knobs in the build and I've only ordered one so I will go back to Ooznest for the other. Also, they only had 4 Rick, In the MiniMill video build Hello Rick In mathew's 'MiniMill' build video he uses 27mm M5 bolts for the wheels on the gantry plates, but I haven't got any of them, but I've got 25mm do you think these will do instead. The ordered parts from OOZNEST will be here tomorrow (Wednesday), So I'll probably be back to pick your brains, 'for warned' and all that. Thanks.
The 25mm screws just aren't quite long enough for the nylock part of the locknuts to grip. Threads will grip but the locking part won't. (Give them a try but I doubt they will instill confidence.)
OK, I'll order those after the first delivery is here. They aren't listed in the Parts list by the way. Do you think OOZNest will stock them? Thanks.
Regarding the 27mm screws, I can't find them anywhere so I'll have to use 30mm instead and hope they don't catch the gantry below. If they do I'll just saw them off the access with a kids hacksaw. The feet for the mini-mill aren't in the parts list of either Openbuilds or OOzNest so where do people get them from.
No, its the set of 4 rubber feet that fit in those 'Cast Corner Bracket'. Its not a problem now as I've found them in the 'Part Store' though I'm wondering how long they will take to get to the UK if I order them on Monday. Thanks.
Interesting. As I haven't watched the video I didn't know those feet existed. They certainly didn't come with my kit... (Not a big deal as I intend to screw my system down to a board.)
That was my thought too. It makes more sense to anchor the mill to the baseboard instead of having it vibrate (because it has rubber feet that make it look nice) every time you turn it on. As I hadn't built one of these rigs before I'm just trying to follow Matt's video as precisely as possible But while I'm doing that I must keep in mind that some things just aren't right and go with my gut feeling if you know what I mean. (won't be ordering them on Monday now)
Rick, Those 27mm Low Profile Screws that Matt uses in the video you haven't seen yet, to connect the wheels to the gantry plate are a pain. As you say, the 25mm screws aren't long enough for the lock nut to grab hold and the 30mm screws are too long even if you include a 3mm spacer the lock nut sits just right, but the spacer makes the gantry plate 3mm higher than its suppose to be. Do you think it will make any difference to the build? I was going to order them from the parts store, but I don't know how long they will take to get to the UK... Any idea. Thanks a lot.
Adding the spacers is really not a good idea as it reduces the rigidity of the system and rigidity is the key component in the system when it comes to making clean cuts in harder materials. It is generally better just to let the screws stick the 3mm out the back side of the nut. And that's pretty much how everybody did it before the 27mm screws were added to the OpenBuilds system. The only place this becomes a problem is with the double wide gantries where the screw extensions on the inset wheels conflict with the interior of the C-beam. In those cases the screws need cut off. Bit of a pain with a hacksaw but if you have a Dremel it goes fairly quick. As for whether you should put everything on hold and wait for 27mm screws that's really up to you. I'm inherently cheap so a few minutes lopping off screws will win out over expensive shipping every time. But again if the screws are just extending out into dead space there's really no sense even worrying about them.
(; i'd take the shipping quote and compare it to the cost of a cheap benchtop belt sander... (; at least thats how I convince my wife I just saved us money heheh and yeah, then knock the 30s down a little
Ok, Rick, I'll stick with the 30mm and hackem off if they're in the way. Now, where did I put that Dremel?
