Re: New Build - Bolt Together CNC
Originally Posted by
jaguar36
As I said before, The epoxy layer is thin enough the stiffness doesn't really matter. If 4Gpa is fine, 18 will be even better.
I was hoping the supplier would have some creep rate data, but they don't appear to (which is slightly worrying). However as long as you stay below about 1/3rd of the epoxy melt temp creep is pretty minimal/non-existent. For SC-15P that should be around 90F, and my shop usually runs a good bit colder than that so I should be fine. Even if it does aned up creeping a few tenths, it would do it consistently, and therefore shouldn't have any noticeable impact.
I'm not set on epoxy yet, but it does seem like the best solution. What other issues did you have with it?
Even/consistent creep is a big assumption. What about different loads on different areas?
I pulled my gantry apart after I found the rails were not flat. I can't remember the figures, but it was about half to one millimetre over 1.2 metres or so.
This was after years of use and with visible indents in the epoxy from the rails.
For a woodworking machine it's ok perhaps, but don't expect perfection.
I don't think the claims of surface plate flatness are true in this application.
I used West system with the super slow hardener (it is not advertised as achieving surface plate flatness. The epoxies claiming super flatness / levelling are not sold in Australia)
7xCNC.com - CNC info for the minilathe (7x10, 7x12, 7x14, 7x16)