Kern uses epoxy granite with aluminium inserts for linear rails beds. They cool the aluminium and apparently use it due to good thermal conductivity.
well not a better choice, I believe it's a close call. I spoke about that because some genious out there referred alu+EG not being a good idea due to thermal expansion differences. anyway I work with what I can get, in the head it just had to be Alu.
lovers gonna love, haters gonna hate :P
Kern uses epoxy granite with aluminium inserts for linear rails beds. They cool the aluminium and apparently use it due to good thermal conductivity.
So what your saying is it's better too insert aluminium bars and have them milled for the linear rails than use steel. Just about to purchase supplies for mine
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No, its not "better" because Kern does it. Kern uses aluminium because its easier to cool, so thermal expansion is less of an issue in their machines. The actively cool the aluminium, which is probably not doable for a DIY machine. For hobby/home/semi-professional use, steel is the better choice, since material properties are more similar to epoxy granite than aluminium.
exactly.
however I don't even consider it a problem, I mean the amount of expansion I don't think it to be relevant at all, if it was an abrupt and wide temperature difference it might but in our case it's a low difference over long time and due to the aluminum great thermal condutivity I don't think it will really matter... maybe it does if you're chasing microns otherwise it's just kind of irrelevant I believe... for me I just use what I can get easier...
Well that’s something worth of looking after and taking notes for further builds! I really like the column ribbed design which will definetly add towards the overall ridgidity. And it’s great to see someone finally added a few mm more to the base width and mounted Y rails as wide as possible to avoid unnecessary X bed overhanging.
Truly, great build my friend!
I’m sure all this attention to machine structure will greatly reflect the end machining results.
By the way, the finish on column casting really looks great!
And I like the way you planed for self-machining the fixture plate. Definitely the best way in my opinion.
Few questions:
1.) What is the square opening on the column for?
2.) Which brand and accuracy grade of ballscrews & rail type did you use?
3.) How will you align the column towards the Y? Measuring it with granite angle surface plate or...?
Once again, congrats on everything you have achieved so far & I’m definitely looking forward and wishing for even more updates on everything you do!
Of course some vodeo inputs would be even more appreciated
Thank you once again for sharing all this with us & inspiring others to take a leap in such beautiful and valuable creations!
Wish you all the best and may all the $/€ gods be with you!
Aleksandar
How is the build going, any progress ?
What ballscrews did you use for this machine ?
These are some great tips! And you’ve got it right; it makes a massive difference. Choosing the right way to cleanEpoxy Floors can be pretty tricky, but this guide made it a lot simpler! Thank you so much for writing; this was helpful!
jesus I feel ashamed that as been more than a year since I mposted something, I've been very busy and most of the time out of country past year, I swear I'll post more pics, the machine is running already but not 100% finished yet.
Yes I took attention to the wider base, designed it in a way that no more than 50% of the table gets unsupported.
to answer your questions:
1- the square open allow me access to the screws for the head nut support.
2- I used Hiwin HGR30 rails HGW30HC cars and TBI ballscrews DFU2005 on xy and DFU2505 on Z, c3 precision
3- yes I bought a precision granite square for all the squaring in this machine
and I'm sorry about not finishing sharing the build but I took lots of pictures and I'll share them asap