Are all polly brushes the same?

[wingnut]

I just bought a 6in Stiff polly brush and it feels more aggressive to the touch then a steel brush! The box sayes Rutland stiff polly. My question is do they make different degree's stiffness in the polly?? I have a 6in SS flex liner and I don't want to damage it. I just was surprised how stiff this thing is! The bristles are larger diameter than the still feel as aggressive.

 

[Mo Heat]

I only have one polly brush, and have never noticed grading of stiffness, so I can't really say, but...

I can't imagine it would damage your SS liner. It's just plastic, after all.

I do know what you mean, though. when i first got mine, i was shocked at how stiff it was. i really have to shove it into the chimney and reversing it takes a deliberate effort. No 'scrubbing' (up, down, up, down) for me. Just down once all the way to the bottom, and then back up all the way to the top.

 

[Shane]

I'm pretty sure they're all stiff. There are a few cleaning systems with softer bristles but the stiffness won't hurt in your situation. I usually don't use the scrubbing action either, typically though three times up and down does the trick.

 

[Corey]

My poly brush is "surprisingly" stiff as well. I actually had to sand it down a little on the belt sander to get it to even move in the flue. Still it is a one way trip.

Im not so sure the reason for the poly brush is purely physical damage. The reason stainless steel is stainless is that it builds up a tightly adhering oxide layer that protects the underlying steel from further corrosion. I suspect that the poly brush is not abrasive enough to damage this oxide layer, but the tips of a steel brush may be hard enough to scratch through it. In that instance, the underlying steel would oxidize to fill in the gap. Dozens upon dozens of steel brush cleanings later and the stainless liner may have a notable reduction in wall thickness which you would like to avoid with a wood burning appliance.

Anyway, JMHO - it could all be a great conspiracy by the poly brush manufacturers, too!

Corey

 

[BrotherBart]

My poly brush is "surprisingly" stiff as well. I actually had to sand it down a little on the belt sander to get it to even move in the flue. Still it is a one way trip.

Im not so sure the reason for the poly brush is purely physical damage. The reason stainless steel is stainless is that it builds up a tightly adhering oxide layer that protects the underlying steel from further corrosion. I suspect that the poly brush is not abrasive enough to damage this oxide layer, but the tips of a steel brush may be hard enough to scratch through it. In that instance, the underlying steel would oxidize to fill in the gap. Dozens upon dozens of steel brush cleanings later and the stainless liner may have a notable reduction in wall thickness which you would like to avoid with a wood burning appliance.

Anyway, JMHO - it could all be a great conspiracy by the poly brush manufacturers, too!

Corey

I think it was Craig that posted a while back that particles of the steel brushes break off and are left on the surface of the liner. Supposedly there is some corrosive reaction between the steel from the brush and the alloy breaking down the alloy.

 

[JAred]

absolutely correct

Anytime you scratch stainless with regular steel it makes it rust. I've seen it many a time in my welding days. Most welders go as far as labeling their stainless brushes for use only on stainless. Although I've only seen cosmetic rust in those instances I cannot say what the long term effects would be on a stainless liner.

 

[Shane]

I sweep many a chimney with the round wire brushes, I haven't replaced a single liner and there are some that our company has been sweeping for 15+ years.

 

[Mo Heat]

I sweep many a chimney with the round wire brushes, I haven't replaced a single liner and there are some that our company has been sweeping for 15+ years.

Shane,

I thought Stainless Steel chimney liner manufacturers explicitely specified poly brushes for sweeping. I thought metal brushes for SS chimneys was a no-no per the makers. Is that wrong? Is it simply annecdotal that poly is required for SS?

 

[Shane]

I'm just speaking from experience it is usually recommended that a poly brush be used as far as I know. But I also know that since I was trained I've always used a round wire brush on everything with no damage to any of the liners, and as stated many of these liners have been installed a good 15+ years. So when I sell a brush for a stainless liner it's always poly and when I make recommendations it's always poly. Now let me make it clear that it is my boss's policy or done with his go ahead when I clean stainless liners with the round wire brush so therefore he is assuming responsibility for any damage that is incurred due to use of said brush, but it hasn't bitten him yet. I would sure think if there was a problem it would have popped up by now.

 

[adrpga498]

I have used poly and found that to reverse motion you need to give it a "quick " pull rather then try to do an up & down brushing motion. This changes the bristles direction all at once. Just a small tip for those that find a 1st time use of polly doesn't reverse so easily.

 

[wingnut]

Thanks for your help everyone!! I know most of the SS liners out there you can cut off with a razor knife. I am just concerned that I might poke a hole through it with this stiff of a brush, Like I said this thing feels pretty mean. I guess I wont know till I try!

 

[Mo Heat]

I know most of the SS liners out there you can cut off with a razor knife.

A razor knife? Not my Elmer smooth SS liner. Or even the flex pipe I have through my damper area. I watched the installer struggle to even get a drill bit (with drill connected) through it. And I watched him beat the flex pipe with a 3.5 lb sledge for about 10 minutes just to flatten it another 1/2 inch. Tuff stuff!

Are you sure you have a Stainless Steel liner, or might it be one of those aluminum things? Big difference.

 

[Shane]

Even the lightest stainless liner I've ever used couldn't be cut with a razor knife. Aluminum no problem, a razor is my tool of choice. What brand of SS liner can you cut with a razor knife?

 

[wingnut]

Most of the liners are rolled with a heaver spiral, the small space in between the spiral rib is very thin! Check the specs. on all the manufactures the thickness is all about the same either .005 or .006 some use the 316 TI a better grade of SS I have seen a box cutter knife used to start the cut on the liners in the rib and a pair of tin snips or side cuts used to cut the rib. I think the main concern with wire brushes is the wire is a very small diameter and could put pin holes in the thinner part of the liner. The poly brush bristles are about 10 times the diameter of the wire brush so it is not as likely to penetrate the steel. Just my thought, not much to back it up other than it makes sense to me.

 

[Shane]

Always have to cut my liner with a sawzall. I'll stick a brush in a 6" chunk of liner tomorrow and stand on it and see if it penetrates, somehow I don't think it'll happen. I'll also try ot cut a chunk of ultrpro with a razor see if that works. (this is of course if I have time)

 

[wingnut]

I wouldn't recommend using the knife method to cut flex liners. All aim saying is it can be done, that is why I was wondering about the the brushes.. I would rather use a 4 1/2 in angle grinder with a metal cut off wheel. You can really bloody up you hand using a knife if your not careful. I have seen people use the knife method when they left there grinder of sawzall up on the roof and there in the basement having to cut a pipe. I think it was mostly about being to lazy the go get the right tool for the job. Definitely not the smartest why to do things. But I still cant hep but think that is why the bristle on the poly brush are so thick in diameter. If you made a wire brush with that diameter bristle it would be way to stiff to get into the pipe.

 

[Haston]

I just bought the same Rutland poly brush and was astonished at how difficult it was to push down the new ss liner on my Regency insert set-up. There is no way I could pull the brush back up, I thought, so I ended up running it down three times and unscrewing it from the pole in the firebox at the bottom of each run. I'm glad someone else brought this up. Initially I thought I had ordered the wrong size, or the wrong size had been put into the 6-inch brush box. Anyway, it was much harder to clean the liner than I expected. In the past, I'd used a sweep, but twice they did not remove the top baffle in the stove and the creosote dust just sat on top of the baffle. The last time, the "tech" decided to move the insert, and he ended up tearing the insert where it entered the stove collar. After that little incident, and the trouble of having my stove off-line this Jaunary while I was negotiating a replacement liner to be installed, I decided to do the sweeping myself. Bought the equipment for less than a singel sweep's visit-- and I can better keep tabs on how much creosote is building up. Note: it goes without saying that I wouldn't have had the confidence to do this without lurking on the board for a while. Thanks. H.

 

[berlin]

Stainless steel is only stainless because of a protective oxide layer of chromium oxide Cr2O3. this oxide layer is very good at protecting stainless steel from corrosion, and is so thin, it cannot be seen with the eye which is why many grades of stainless remain quite shiny. however, in oygen poor or CL rich environments pitting and corrosion can develop. Stainless can rust very quickly if it fails to create the protective oxide layer. This happens when things like high carbon steel chimney brushes are run over it thus scratching the oxide layer and forcing bits of carbon steel into the stainless. so if you want to ensure long life from your stainless liner, don't use a steel brush; pitts in stainless may only appear as a pinhole on one side, but the cancer can be as large as dime on the OPOSITE side that the corrosion began, this is expecially true in corrosive environments such as a chimney.

I personally hate polly brushes; perhaps they are out there, i haven't really looked, but i would like to see some stainless brushes made that would eliminate this problem.

 

[wingnut]

Do you think it is possible to scratch the ultra thin layer with the poly brush? If so wouldn't that cause problems with corrosion also? Or does it happen with a metal high carbon brush? You are right a SS brush seems to be the way to go.

 

[berlin]

I'm not sure if a poly brush would scratch the layer of oxide; however if it did, i'm sure it would scratch it much less than a steel brush would. Regardless of whether the liner is scratched or not, the most important reason not to use a steel brush is simply because that when it does scratch the oxide layer, it will at the same time leave bits of carbon steel which prevent the protective oxide layer from forming and which allow corrosion to begin and a pit to form.

 

[MountainStoveGuy]

I was always under the impression that a harder material can scratch somthing softer, but not vise versa. I faintly remember something about that from chemistry, and there were no exceptions to that rule. I could be wrong...

 

[berlin]

"I was always under the impression that a harder material can scratch somthing softer, but not vise versa"

well, that is true, however that tends to oversimplify things. a Softer material leads to scratching of a harder material if harder particles become embeded in the softer material. this is the idea that abrasive blades, diamond cutting blades etc. rely on.

 

[Metal]

The oxide layer on SS forms extremely quickly, so you will not see corrosion due to scratches. The only time that would be a problem is in marine conditions, where you are underwater and there is not enough oxygen available to form the protective oxide layer before corrosion begins.