We have a lot of customers who want to pair their Spindle with an IKEA bed frame. As is, most IKEA frames will not offer enough support for a Spindle. Fortunately, the critical mass of IKEA customers has provided a robust hacker community and their DIY solutions can be found by exploring Google Images, YouTube or Pinterest.
This YouTube video highlights one of the shortfalls and demonstrates one way to fix it.
There are many other postings online with pointers on how to add support to your IKEA bed.