comma or dash

Hi,

When you have sentences that have phrases like 'for example' or 'that is' as a part of your sentence, would you resort to using a comma or a dash (or a pair of dashes)? Normally, it seems to be recommended that a comma is to be used ,and I tried to find more examples of such comma usage online but very little information seem to be available. Help.

He has some tools he can use to build a dog house at home, for example a wrench and a plier.       

But if the underlined part is set in the middle of the sentence, I am not sure a comma would be all that perfect.

Some tools he has at home, for example, a wrench and a plier, can be used to build a dog house. 

For emphasis (for whatever reason), a pair of dashes can be used.

Some tools he has at home -- for example, a wrench and a plier, can be used to build a dog house.    

Can you give me some examples with 'that is'?

Thank you, Feebs11

Did you mean 'parentheses', not 'brackets'? Those punctuation marks you put around seem to be paretheses. 

Would you say this use of a comma, where you place a comma at the end of sentence, would be correct or good?

He has some tools he can use to build a dog house at home, for example a wrench and a plier.

I do seem to see this type of comma usage in dictionaries a lot.  

Hi,

Here's a vey small off-topic note.

Don't say a plier. Pliers are like scissors, eg a pair of pliers, some pliers.

Best wishes, Clive