Tony Vitler, an organiser with the ACT branch of the Construction, Forestry, Mining and Energy Union, rang assistant secretary Jason O'Mara at 7.15am on April 21 to tell him the pieces were in place.

"We're down at Brooklyn [Apartments], they're attempting to set up a [concrete] pump. We're going to have a bit of a fucking crack," he said in the secretly-recorded phone call.

Commission counsel assisting, Jeremy Stoljar, SC, put it to Mr O'Mara an intimidation campaign had been planned at a meeting with himself, the organisers and branch secretary Dean Hall on April 10.

Mr Stoljar said Mr Vitler was excited and speaking "like a man about to go into battle" on the tape.

Mr Stoljar put it to Mr O'Mara that Mr Hall was furious the contractor, Milin Builders, did not have a union enterprise agreement. He said the plan was to disrupt the concrete pour.

Mr O'Mara said the Turner visit was just a safety inspection. He denied the April 10 meeting was a council of war.

Mr Hall was concerned organisers were being slack with their workplace visits and gave them a "tune-up".

"We had a meeting, we got a dress down and we went home on a Friday afternoon with our tails between our legs," Mr O'Mara said.

The commission also heard a recording of a phone conversation between Mr O'Mara and a Sydney building company manager made on April 22 this year.

The company, which had not operated in Canberra before, was doing business with Fyshwick's Richard Crookes' Constructions.

Mr O'Mara told the manager, whose identity has been suppressed, the CFMEU had issues with Crookes.

"They've treated us with a little disrespect; we haven't shown them the attention we need to," he said.

Mr Stoljar put it to Mr O'Mara the conversation was about ensuring only union-approved contractors were used.

Mr O'Mara said: "I would like my members to be employed, if I could."

Mr Stoljar asked Mr O'Mara what "attention" meant.

"Do you mean interrupt the sites on which they are working?" he said.

Mr O'Mara said: "I don't know what we're talking about here."

In other developments Johnny Lomax and Dean Hall will now not testify until late September at the earliest.

Commissioner Heydon told Mr Stoljar, he would not be happy for Mr Lomax and Mr Hall to be called this week only to experience a prolonged adjournment.

Mr Lomax pleaded not guilty to blackmail after being arrested in July.

The commission has been trying to squeeze five days of scheduled hearings into four this week to accommodate hearings into the Queensland branch of the CFMEU scheduled for Brisbane from September 14 to September 25 and a CFMEU conference next week.

Harsh words were exchanged on Thursday when John Agius, representing the CFMEU, took umbrage at the way Adam Morison began his cross-examination of organiser Kenneth "Dusty" Miller

Mr Morison is representing Canberra builders Sam Delerenzo, Petar Josifoski and John Nikolic.

Mr Agius accused Mr Morison of demeaning the commission and giving lawyers a bad name.

"This has been the case every time Mr Morison has questioned a union official," Mr Agius said. "We get this sarcastic, pompous, arm-swinging cross-examination."

Mr Morison said if Mr Agius was objecting even before he started asking questions it was proof his questioning was having an impact.

Commissioner Heydon said Mr Agius had a point.

"[Mr Morison] it might be a good idea to avoid sarcasm and excessive volume," Commissioner Heydon said.

The hearing continues at 10am on Friday.