Apparently yes… if you have access to a laser cutter!
Not prepared to spend upwards of £50 on a tyre system, Stravaging bought himself a roll of foam on ebay for 20 quid and used his school’s design equipment to see if he could do his own version for cheaper. Although in truth, he probably could have done it with a scalpel if he had the time.
He’s since tested the inserts and they seem to be doing the job. If you fancy a pair yourself, head over to his Facebook where he’ll be giving some away.
More info here: https://stravaigingmtb.com/2017/07/19/can-you-make-tyre-inserts/