While surfing about on YouTube the other day I stumbled across this link: http://m.youtube.com/watch?v=T1_CmFuIKtM&desktop_uri=/watch?v=T1_CmFuIKtM It shows a fellow with a Warn 8000 winch with no line or load powering the drum in the "in" direction and taking temperature readings over the course of a few minutes.

His video showed that the slight dragging of his winches internal brake (even in the "power in" mode was causing that spot in his drum to reach up to +/-200'F.

This led me to wonder how common this was. My Dad has a few year old Warn 9.5XP that he is replacing the line on, so I asked him to take a look. His winch to the best of my knowledge has never been apart, and is seldom used.

I asked him to look at the video and do the same test as best he could. He reported that he started with a cold winch, (had not been used in weeks), free-spooled out the old cable. (did not power out) and unhooked it from the winch. Once the cable was off, he plugged in the remote and ran the winch in the power in (only) direction for a few minutes. He doesn't have the fancy fluke meter, but he reported that the drum (not the motor) did get quite hot. He did the test again a little while later once the winch had cooled, but powering out for about a minute. He said this generated substantial heat. The motor never got more than just warm. He said that he has never had a problem with the brake, and I have seen the winch power in smoothly before. (no odd sounds)

So, this brings me here. I'm trying to figure out how common this is, and if all warn (style?) winches generate at least some drag heat while in the power in mode. And if this is the case, is this something we have to really worry about when switching to the amsteel style winch ropes.

I'm looking for guys who are willing to give this a quick try and let me know. (it's been a while since you took a look at that drum anyway right?) When looking at the online pictures and description of the warn style brake, I'm not sure it *can* 100% eliminate contact with the drum to avoid generating heat in the line in direction.

So if you could, I'd love to hear about your results.

 

Update.

I spoke with one of my buddies and he said his M8000 generates some heat over the brake area while powering in as well. Enough that he couldn't hold his hand on the drum after 3 minutes or powering in. So, ether we have a fluke of 3 broken or mis-adjusted winches, or we may be a problem when using the Amsteel lines with standard/older planetary style Warn winches.

Something else to note is that Warn seems to be slowly changing its product line to accommodate the synthetic ropes. If you look at the drawings for each of their winches you will notice that on each of “-s” winches that the drum diameter has been increased from 2.5”od up to 2.625”od. I am not certain if this is to add strength to the inner drum wall (to prevent the synthetic from tightening and indenting the drum), or if it is a double wall drum to reduce brake heat being transferred to the rope. The new Zeon line seems to have a much larger drum diameter of 3.15”od across their line.

Warn Industries - Jeep, Truck & SUV Winches: M8000
Warn Industries - Jeep, Truck & SUV Winches: M8000-s

Samson Rope (the Manufactures of Amsteel Blue synthetic rope) state that the Critical Temperature of HMPE fiber is 150'F. However I have been unable to get any hard information about just how much damage the rope will suffer in the +/-200'F range and if it will be permanent, or if it is temporary and the rope will regain its strength once cooled.

This document seems to indicate that the Amsteel blue could lose as much as 75% to 80% of its strength at +/-200'F. (Figure 2) http://www.samsonrope.com/Documents/...PT2012_WEB.pdf But there may also be a time-at-temp component involved here as well. The document wasn't intended for our application and is a little hard to read in that respect. So we may not be dealing with an instantaneous loss of strength once temperature is applied. Which is encouraging. But method of testing could be making all the difference here.

I am waiting on a reply from both Warn and Samson Ropes. It will be this weekend before I can get over to my dads house with some calibrated temperature equipment to check his winch. In the mean time, if anyone has any info on the rope specifics, strength loss at temp or normal operating drum temps. I would certainly appreciate it.

 

Update # 2

Got a call from Warn this morning in reply to my email. Still have not had a reply from Samson Ropes.

He basically said that;

Yes, the internal brake in most planetary gear winches will generate some heat while powering in. But it will be nowhere near the heat generated while powering out. The good news is that he thinks, and I now agree that the test I was duplicating (the one from the video) was slightly flawed. (it edges more towards a worse case heat generation scenario) From what he said, in real life the winch will not normally be used the way the test was being run. Most people wont be running the line 100% out and then spooling it back up all at once like that under no load.

He also said that under a slow controlled winch-in that the drum will be running at a much slower pace. That there will likely be frequent pauses during winch-in operations. And that from his understanding from the test engineers, a winch under load is better able to disengage its internal brake vs an unloaded winch.

He also mentioned that if you suspect that your brake is mis-adjusted and is dragging excessively. That you should check the amperage while the empty winch is spooling in under no load. And that anything over about 100 amps (I believe) may indicate excessive drag in the brake assembly.

I think that I would be hard pressed to find a more stand up company to deal with. They are mighty proud of their products, and from what I can tell, they have every reason to be.

So, This is all good news. The only nit, is that we now know that the winch brakes are generating some heat while spooling in during normal operations. It's likely not enough to worry about if you are using the Warn heat resistant synthetic rope, steel, or another cable with a heat sleeve or some heat resistance.

But for the folks running a straight drum of the Amsteel blue it is a tentative concern until we can get some more information from Samson Ropes regarding the critical temp / time at temp issue.

I am planning on doing a bit more testing to see if I can get an idea what kind of temperatures we can expect between the drum and the rope during "normal" operations.