I disagree with Jaysen Medhurst. I have done exactly what you described and have had a great experience with it i'll give you the bullet points as to why I agree with your philosophy.
1.) You are paying down a significant amount of interest in terms of dollars over the life term of your loan. So if you're paying 64K against the principal and subtracting 30K in interest that's a significant savings when looking at it holistically.
2.) You are shortening the lifeterm of your primary mortgage which for most average Americans is the largest expense we pay for so you have a higher chance of fast tracking yourself to retirement or financial freedom.
3.) You are creating your own financial instrument by leveraging your home with a HELOC. Now it is true there are risks like a recession the bank could close a line of credit. However that's being stated by the writer above almost as an inevitability and for the rest of time. The reality is there are many banks offering HELOC's that you could switch to if this were to happen and in a worst case scenario wait it out a few years and then try again. After all there's no reason why you couldn't try again... it's your primary mortgage were talking about it's not going anywhere and neither are HELOC's.
4.) HELOC's generally speaking are a very cheap form of capital. Most HELOC's are around the 4-5% Variable rate (currently) and historically are below 8% with only a few points in the last 50 years going above that and with a coming recession generally speaking interest rates typically go down and if you're worth your salt as your investor literally one homes profit in a given year could pay for any interest accumulated.
5.) If you believe in Robert Kiyosaki's principals of converting liabilities into assets then simply put paying down your mortgages principal and converting that into your small businesses bank account with a HELOC is in theory converting a liability into an asset.
It's very easy for people to simply say no that's a terrible idea we for some reason have this terrible stygma associated with paying down principal and then leveraging that equity to your own advantage, personally i've never understood why I think it's a brilliant move one that I can tell you has worked extremely well for me.
I'll leave you with item to ponder on. Tell me, what risk do you have by paying down your principal (debt)?