Chipped brake drum Would you use it?

[Srt20]

I'd have no issues using that drum whatsoever.

I'd be pissed if I bought one like that though.

 

[Jetronic]

Yeah same here. In that location the beak doesn't bother me on a used drum. if i just paid for a new, I'd try to get another if it was worth my time and effort and I didn't do it

 

[mazdamonky]

I'd have no issues using that drum whatsoever.

I'd be pissed if I bought one like that though.

Yeah same here. In that location the beak doesn't bother me on a used drum. if i just paid for a new, I'd try to get another if it was worth my time and effort and I didn't do it

These were my sentiments exactly. I purchased a new rotor that was damaged. If I had dropped it myself, I would have just absorbed the responsibility myself and probably just used it. My main concern is that means either it was dropped which could have caused more damage than it appears or the casting could have been subpar in that area which may lead to even further issues.

 

[Jetronic]

it's common for drums to crack there, it truly is the most vulnerable spot. Trouble is you already painted them, but there's no paint on the cracked surface... I'd deny that claim based on those pictures to be honest... in any case the damage isn't functional and likely not visible once mounted with a wheel covering the drum

 

[PimTac]

Not blaming you mazdamonkey but the picture looks like the chip happened after painting. One possibility is that the drum was damaged but not visible. You painted it and set it down and the chip came out.

Take a look around where you painted the drum. That chip might be there.

 

[ABN_CBT_ENGR]

I purchased some brake drums from rockauto and one of them came in with a chip on the outer section. It does not appear to have occurred during shipping but there was a large cut/knock on the box where it appears the damage occurred. Sadly I did not notice the damage until after I had painted the Drum.

I must ask, how did you spray a drum and not get even a hint of mist in what appears to be a totally fresh and un-oxidized break with very crisp paint lines along the fracture zone as clearly shown in your picture # 836? (In addition to not noticing that missing piece "during" the painting process?

 

[ABN_CBT_ENGR]

My main concern is that means either it was dropped which could have caused more damage than it appears or the casting could have been subpar in that area which may lead to even further issues.

Hard to discern from a picture but the fracture pattern appears to be a typical reaction to an impact against a shear ledge and the mass of the casting is probably fine for design use. What little the grain can be enhanced before it blurs indicates a nice crisp "moment" type fracture.

Again, hard to determine from pictures but I don't see anything indicating any type of defect in the overall casting.

 

[nthach]

It’s your call. Chinese rotors tend to be hit or miss. Cast iron is a brittle material by its nature.

 

[ollie]

Not blaming you mazdamonkey but the picture looks like the chip happened after painting. One possibility is that the drum was damaged but not visible. You painted it and set it down and the chip came out.

Take a look around where you painted the drum. That chip might be there.

If you zoom in the picture you can see he is being honest. There is overspray under the missing chip.

 

[ABN_CBT_ENGR]

There is overspray under the missing chip.

Then explain how a spray completely missed the fracture zone but has a crisp line around the perimeter.

 

[ollie]

Then explain how a spray completely missed the fracture zone but has a crisp line around the perimeter.

He sprayed from the face of the drum. Doubters gonna' doubt. I have no reason to distrust this gentlemen.

 

[PimTac]

If you zoom in the picture you can see he is being honest. There is overspray under the missing chip.

His honesty is not being questioned by me. I don’t see the overspray unless it’s that faint shadow on the rim beyond the chip.

My guess is that it was a casting defect or the drum got dropped or mishandled before it was sent to him which resulted in a fracture. He painted it and then set it down and the fractured part came off. As the ENGR commented the paint line is clean around the fracture line.

I’m hoping the OP finds the chip on his workbench or wherever he did the painting.

 

[ollie]

His honesty is not being questioned by me. I don’t see the overspray unless it’s that faint shadow on the rim beyond the chip.

My guess is that it was a casting defect or the drum got dropped or mishandled before it was sent to him which resulted in a fracture. He painted it and then set it down and the fractured part came off. As the ENGR commented the paint line is clean around the fracture line.

I’m hoping the OP finds the chip on his workbench or wherever he did the painting.

It's possible. it looks like overspray to me but I'm not there. I'd just put them on and call it a day.

 

[atikovi]

I would use it and not worry about it unless it’s some kind of performance application.

^This. And I can't imagine any performance car made in the last 30 years that had drum brakes.

 

[hemitom]

^This. And I can't imagine any performance car made in the last 30 years that had drum brakes.

Nissan Micra baby !!!

 

[ABN_CBT_ENGR]

His honesty is not being questioned by me. I don’t see the overspray unless it’s that faint shadow on the rim beyond the chip.

My guess is that it was a casting defect or the drum got dropped or mishandled before it was sent to him which resulted in a fracture. He painted it and then set it down and the fractured part came off. As the ENGR commented the paint line is clean around the fracture line.

I’m hoping the OP finds the chip on his workbench or wherever he did the painting.

I blew it up in Corel and really looked at the color and pixels just to see if anything revealed itself. ( things we do in a hotels to pass time) Would be better for a higher res image but we work with what we have.

There is barely visible evidence on the left side of the break where the blue paint appears to have run into the grain from the top. ( not a spray, its following a grain)

I've seen this in counterfeit pipe fittings before across the pond.( those were usually too much porosity though and paint went in my capillary action)

So, based on that, I'm in the "pre paint" fracture cause unknown group and for reasons unknown it fully separated post painting.

 

[spasm3]

I would want another. But if i were going to use it, i'd use a die grinder and a stone and smooth it out, remove any heat stress risers first.

 

[PimTac]

I blew it up in Corel and really looked at the color and pixels just to see if anything revealed itself. ( things we do in a hotels to pass time) Would be better for a higher res image but we work with what we have.

There is barely visible evidence on the left side of the break where the blue paint appears to have run into the grain from the top. ( not a spray, its following a grain)

I've seen this in counterfeit pipe fittings before across the pond.( those were usually too much porosity though and paint went in my capillary action)

So, based on that, I'm in the "pre paint" fracture cause unknown group and for reasons unknown it fully separated post painting.

I’m on a iPhone but I zoomed in and I see what you mean.

 

[ollie]

I'm not analyzing it too much. It's only a chipped drum.

 

[JHZR2]

I must ask, how did you spray a drum and not get even a hint of mist in what appears to be a totally fresh and un-oxidized break with very crisp paint lines along the fracture zone as clearly shown in your picture # 836? (In addition to not noticing that missing piece "during" the painting process?

Take a look at my harmonic balancer thread. At first after I damaged the potmetal pulley, I didn’t even see the damage. It was still hanging on even after I messed with it. Only when I really messed with it, did I break the piece off in earnest.

it can happen, it might have been a very minor crack until OP was examining the paint job, saw, messed and broke it off. I’m willing to give the benefit of the doubt based upon how my pulley broke off. The truth is between OP and their creator, not us.