"Tip the scales at" is an idiom that simply means to have a particular weight. However, there are several common synonyms that can be used to replace this phrase. You could say someone "weighs in at" a certain amount, or "registers at" a particular weight. Another option is to use the phrase "come in at", as in "he came in at just over 200 pounds". Additionally, you can use the word "clock" to indicate a weight, as in "she clocked in at 155 pounds". Finally, you could simply use the verb "to weigh", as in "he weighs 180 pounds". Each of these synonyms can be used interchangeably with "tip the scales at".