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R.Keith
11-24-2010, 08:01 AM
Is there a post using pictures and hopefully small words
to describe a reliable procedure for heat treating 1095 using
a forge, McMaster-Carr 11 sec, and my wife's old toaster oven.

I am finding great information here on the forum but haven't
had it all sink in yet.

I think I let my last try set out of the quench too long.
It didn't seem to get very hard, at least with the file test.

And I may not have enough quench oil in the roasting pan.
Just deep enough to cover the blade when held horizontal.

Again, any and all help appreciated.

Kevin R. Cashen
11-24-2010, 09:22 AM
With quenchants volume is important, treat it like computer memory or hard drive space… you can’t have too much but you can have too little. You always want enough to get well below the surface with whatever you are quenching and room to vigorously move the blade if you are not moving the oil by some means.

You have probably heard people bemoan how tricky 1095 can be, this is not true… unless you are heat treating with a forge. 1095 will be a bit more picky about exact temperatures and times than 1075, 1080 or 1084 so to be honest you have your work cut out of you using the simple equipment you describe.

Unless special arrangements have been constructed using baffles and pyrometers, what you have with the forge is the same old routine anybody would use for any steel- heat to nonmagnetic or to where a well trained eye can spot the transformation and quench, hoping for the best.

There are many ways in which knifemakers handicap themselves with methods or material and tool selections but the toaster oven has to be close to the top of the list, it is probably one of the worst heat sources for tempering and yet is still one of the most popular. I remember my toaster oven days and if I recall correctly it was the price and the shop space taken that was most appealing to me about it. As time went on the product became more important than any of these considerations so as soon as I had means of measuring and accurately assessing the job the toaster oven was doing it got tossed behind the shop.

Good, reliable tempering comes from very steady thermal mass, for this a full sized kitchen oven is superior to the toaster oven, but I was there and did that as well and I understand the near fatal hazards of your wife finding her next batch of cookies tasting suspiciously like McMaster-Carr oil.

Home ovens (large kitchen or toaster) will work a little better with 5160 or 1084 but when you get above .8% carbon, and start really nailing the soak, tempering will get quite a bit more intense and may push these tools to their limits.

If you still wish to work with 1095, until you can get a tempering unit to really take on that steel you can put large pieces of steel in the toaster oven to help shield the blade from the heating elements and even out the thermal mass. Give it plenty of preheat time and never rely on the thermostat of the oven to judge the temperature, use a reliable thermometer or pyrometer.

Doug Lester
11-24-2010, 09:57 AM
Also be aware that there can be rather large differences in the manganese levels in different makers 1095. The lower the manganese level the tricker it will be to heat treat. I understand that Aldo Bruno, the New Jersey Steel Baron who advertises below, carries some 1095 with a higher manganese level. Kevin right when he says that heat control with a forge can be a bear but it has been done. I found that one mistake that I had been doing with my forge in heat treating is to run it too hot. Now I only run it wide open while I'm heating it up and then cut the gas and the air back until the inside is more of a bright red rather than orange-yellow. You can also add to the thermal mass of a toaster oven by putting a tray of sand into it and sticking the blade into the sand to temper. Make sure that you heat the sand fisrt and use a thermometer to measure the heat of the oven; don't rely on the dial setting, even with the kitchen oven. As far as introducing the odor and taste of quenchant oil to the kitchen oven, you can get around it by scrubbing the oil off in hot soapy water.

Doug Lester

R.Keith
11-24-2010, 09:04 PM
Ok, where to begin?

Kevin,
I've got plenty of quenchant so I'll fill up the roasting pan, and agitate back & forth or up & down but not side to side.

I got all geeked up after a workshop & wanted to get started so I ordered in the steel we used, and since my wife wasn't
comfortable with me building a forge or HT oven she wanted me to buy a forge, so I did. And I've already been informed
the stuff stays outside , so I'm stuck with the toaster oven until I find a better solution. Also limited space in the garage prohibits
a full size oven.

So, I've got 15 more feet of 1095, a neat Chileforge Tabasco, 5 gallons of McMaster-Carr 11 sec. and a Black & Decker toaster
oven.

Sounds like I need to get some large pieces of steel and/or use sand in the tray, and a good thermometer for the oven, and plenty
of preheat time.

Doug,
I will have to make due with this steel for now. At least till I learn enough to be able to make any kind of difference with my
technique. I can, however, learn how to adjust my temp in the forge and back it off quite a bit.
I'll call Aldo for the next batch of steel.

I appreciate the information gentlemen.

Keith

McClellan Made Blades
11-25-2010, 07:27 PM
Keith,
If you want to increase your chances of success and your knowledge, I would HIGHLY recommend ordering (at the very least) a stick or 2 of Aldo's 1084, if you can get any other 1084 that'll do, Aldo's is just the best that's all, he has Vanadium added to it, which gives the steel a bit more toughness, but the rest of the 1084 will work the way you need it to. Because 1084 is heat treatable with the set up you have, 1095 requires more specific temps and soak times, 1084 is the BEST beginner steel for any knife maker, while saying that. Many knife makers use 1084 for most of their bigger knives, because it is good steel, it doesn't cost a lot, and it makes some wicked sharp blades. A friend of mine uses Aldo's 1084 almost exclusively. He has tested it over and over, the sharpness, edge retention is amazing. Of course he has perfected his process with equipment a little better than yours, I do mean a little better, he built his HT oven, uses a pyrometer for the temperature, and quenches it in Houghtons (I think) Type K.

The bottom line is this, you can take a 1084 blade heat it above
non-magnetic, that means get it red hot check it against a magnet, once it stops attracting, heat it a little more and then quench, a temper in the toaster oven will work for this steel, when you get into the more finicky steels, the more specified equipment is necessary, I'm not saying it can't be done, I'm saying for a beginner it is better to start with a steel that is MORE forgiving, 1095 is not forgiving at all, it is a great steel and I use it all the time. But it gave me nightmares until I got my kiln, once I was capable of getting a consistent temp for a prescribed amount of time, I started getting better results. Save the 1095 you have for later on, 1084 is your best route right now.

Tell you what, you pay the shipping, and I'll send you a couple of pieces of Aldo's 1084. Let me know what size you need it, as in not shorter than XX". Depending on the length you need, it shouldn't be much more than 10 bucks, just let me know. And another thing, if you need to have a blade HT'd, I'd be glad to do it for you, no charge, just pay the shipping. My disclaimer is that I'm no professional, I get great results with my stuff, just make sure that the edge isn't super thin, if it's a stick tang make sure there are no sharp corners, like for the shoulders of the guard or any deep scratches. These can cause a stress fractures during HT, just let me know, Rex

R.Keith
11-26-2010, 10:17 AM
Keith,
If you want to increase your chances of success and your knowledge, I would HIGHLY recommend ordering (at the very least) a stick or 2 of Aldo's 1084, if you can get any other 1084 that'll do, Aldo's is just the best that's all, he has Vanadium added to it, which gives the steel a bit more toughness, but the rest of the 1084 will work the way you need it to. Because 1084 is heat treatable with the set up you have, 1095 requires more specific temps and soak times, 1084 is the BEST beginner steel for any knife maker, while saying that. Many knife makers use 1084 for most of their bigger knives, because it is good steel, it doesn't cost a lot, and it makes some wicked sharp blades. A friend of mine uses Aldo's 1084 almost exclusively. He has tested it over and over, the sharpness, edge retention is amazing. Of course he has perfected his process with equipment a little better than yours, I do mean a little better, he built his HT oven, uses a pyrometer for the temperature, and quenches it in Houghtons (I think) Type K.

The bottom line is this, you can take a 1084 blade heat it above
non-magnetic, that means get it red hot check it against a magnet, once it stops attracting, heat it a little more and then quench, a temper in the toaster oven will work for this steel, when you get into the more finicky steels, the more specified equipment is necessary, I'm not saying it can't be done, I'm saying for a beginner it is better to start with a steel that is MORE forgiving, 1095 is not forgiving at all, it is a great steel and I use it all the time. But it gave me nightmares until I got my kiln, once I was capable of getting a consistent temp for a prescribed amount of time, I started getting better results. Save the 1095 you have for later on, 1084 is your best route right now.

Tell you what, you pay the shipping, and I'll send you a couple of pieces of Aldo's 1084. Let me know what size you need it, as in not shorter than XX". Depending on the length you need, it shouldn't be much more than 10 bucks, just let me know. And another thing, if you need to have a blade HT'd, I'd be glad to do it for you, no charge, just pay the shipping. My disclaimer is that I'm no professional, I get great results with my stuff, just make sure that the edge isn't super thin, if it's a stick tang make sure there are no sharp corners, like for the shoulders of the guard or any deep scratches. These can cause a stress fractures during HT, just let me know, Rex

Rex,
Excellent idea, I'll take you up on it.
I'll PM my info.

Thanks,

KHKnives
12-19-2010, 05:39 PM
awesome stuff here, i use 1095 and love the stuff. i heard great things about 1084 but i have trouble finding it. i heat to non magnetic with a torch while using a laser thermometer on the opposite side, and quench in a horrible mixture of engine sludge/used diesel oil/fresh trans fluid, i know its a sin. i temper in a large oven and check it with my laser from time to time. my 1095 gets hard as a rock though, if i need to make a small filework change, you can bet one of my files will be destroyed. i like 1095 because i can treat it with normal tools, until i can buy better equiment.

McClellan Made Blades
12-19-2010, 06:22 PM
awesome stuff here, i use 1095 and love the stuff. i heard great things about 1084 but i have trouble finding it. i heat to non magnetic with a torch while using a laser thermometer on the opposite side, and quench in a horrible mixture of engine sludge/used diesel oil/fresh trans fluid, i know its a sin. i temper in a large oven and check it with my laser from time to time. my 1095 gets hard as a rock though, if i need to make a small filework change, you can bet one of my files will be destroyed. i like 1095 because i can treat it with normal tools, until i can buy better equiment.


KHKnives,
I'm curious, have you ever broken one of your 1095 blades? While steel of any kind is fairly easy to get hard, the part where you transform it to the fine line between hard enough to keep and edge and soft enough to not be brittle is a lot more difficult, I know an experienced maker can HT any of the steels they know how to work, but I found 1095 to be a huge PITA! I got an edge on my 1st 1095 blade, it was incredibly hard, and super sharp, but the brittleness was a problem, small chips along the blade after chopping seasoned oak left me very unhappy with it. If you do break one of your 1095, blades examine the grain structure, look for larger chunks of...sort of the grain, I know what I'm thinking but can't explain it, Kevin Cashen can explain it better. Bottom line is, if your blades perform well, and aren't brittle there isn't a problem, but what you might want to lookout for is the possibility you might have for the development of pearlite, just something to look out for. BUT if it aint broke don't fix it! Just keep that in mind.

As for 1084, you can get the very best 1084 from Aldo Bruno, THE New Jersey Steel Baron, http://njsteelbaron.com/, Aldo has the best steel there is, gives fantastic service and is all around one of the best guys you'll ever meet! His 1084fg, (the fg, stands for "fine grain"), has some vanadium added to it, which adds some toughness to the steel, really wonderful stuff! The web site is new, it list several of the steels he has available and you can order it straight from the site.

Another tip - for files, if you buy them from Sears, they are covered under their Craftsman warranty, dull it, break it, take it back and get another one FREE!

BTW, Spartanburg South Click!? Are you a Gamecock? If so, I just wanted to commend y'all, on a great season, I really expected the SEC Championship game to be a lot tougher than what it was, and one more thing....
WAR EAGLE!!!!!

Glad your enjoying the group, ask more questions, share more experiences, it's the way we all learn! Thanks Rex

KHKnives
12-19-2010, 08:45 PM
Haha, I'm not really into football but my girlfriend appreciates the comments and agrees. As for being brittle, the karambits I make are 3/16" thick and the blades are 2 1/2" long max. I put a chisel grind on them, I have one I use as a work knife and haven't had any problems, that's not to say my HT process is super solid, but it has served me well. I buy my tools from the MAC tools dealer because I'm a mechanic, I have a lifetime guarantee on my files, car bide burrs, its awesome. I have some craftsman though. Excellent thread

Sean Cochran
12-19-2010, 09:19 PM
Here is what I found about 1095. I used it with a forge as has been described in this thread and got good results, sharp edge good retention etc. So I always thought why is everyone talking about 1095 being unforgiving? But once I used a kiln and got a good HT I realized how bad my HT had been. Im not saying that its impossible, just for me it was to hard to get repeatable results with the forge.

1084 however, is much easier.

McClellan Made Blades
12-20-2010, 10:41 AM
Here is what I found about 1095. I used it with a forge as has been described in this thread and got good results, sharp edge good retention etc. So I always thought why is everyone talking about 1095 being unforgiving? But once I used a kiln and got a good HT I realized how bad my HT had been. Im not saying that its impossible, just for me it was to hard to get repeatable results with the forge.

1084 however, is much easier.

Sean,
That is exactley what I meant! In my attempst to be informative, without stepping on any toes or hurting any feelings, I tend to get long winded, sometimes without getting my point across. The thing I was really wanting KH Knives to understand is that a problem could arise with the process, and it's easily avoidable by using some of Aldo's 1084fg. I know I seem to push to Aldo's steel, and it's for a good reason, I've used Admiral's, and a couple of other (so callled) 1084, the results were not the same. Aldo breaks his back just to supply KNIFEMAKERS! That means a lot to me, I would hate to see the day we have to go back to relying on the scrapyard for steel, Besides, I will shamelessly push ALL Knife Dogs members products, because I feel like being apart of this forum does and should have that added benefit, especially from those that help others with problems. I've got a running list of people to buy something from should the need for their product arise (and I can afford it). Just to show a little gratitude, for their support of new and old makers. When any of us run into a problem and someone steps up with the answer we couldn't figure out or come up with, that is relief like freash air in a vacuum! That's just the way I am, while price is important, sometimes it's about principal! Rex

McClellan Made Blades
12-20-2010, 11:11 AM
Haha, I'm not really into football but my girlfriend appreciates the comments and agrees. As for being brittle, the karambits I make are 3/16" thick and the blades are 2 1/2" long max. I put a chisel grind on them, I have one I use as a work knife and haven't had any problems, that's not to say my HT process is super solid, but it has served me well. I buy my tools from the MAC tools dealer because I'm a mechanic, I have a lifetime guarantee on my files, car bide burrs, its awesome. I have some craftsman though. Excellent thread

The football thing I was kidding about...as much as a country boy from ALABAMA, who is an Auburn fan can kid, we treat NCAA Football like Northerns treat the pro's! It's been since 1957 since Aubrn has played for the title, so it;s kind of a big deal down here, sitting in the shadow of the Great, Paul "Bear" Bryant. But our time has finally come again, and it happened in MY life time, totally unexpected!
Back to knives, on short blades like a Karambit it might not be a problem, but if you progress into larger blades, you will want to get the HT a lot closer, or bettter yet use a steel like 1084 that is alot easier to nail the HT, too hard is as bad as too soft, doing the little things that can make your blades a little better each time you make one is our constant goals, and if you were to make a big chopper using the 1095, the results might, not saying will, you may have it dialed in and know exactley what you're doing, be less than desireable. I'm not saying 1095 makes bad choppers, they DO make great choppers, with the correct HT and temper. My experience is the only way I know of to get it dead on, is with the use of a kiln. So the temps can be controlled specifically where you want them to be and held there for the specific amount of time you want it held there. I know Kilns are expensive, but there is an alternative to the more expensive kilns like EvenHeat and Paragon, both are made for the specific purpose of knifemaking, there is a company called Sugar Creek Industries, they make kilns for pottery and glass, but they also have one for knifemakers, look them up under, Smart Kilns, they aren't priced like the others, mine is about a year and a half old, it's the large knifemakers model and cost me right at $500.00, I don't think that included shipping, but I believe they are in S. Carolina, if I'm not mistaken. As long as you won't need one to HT over 2000 degrees, it's a good choice, and great value for the money. Hope this helps, do keep in mind that if your getting satisfactory results the way you are doing things now, DO NOT take what I say as the gospel! I'm speaking of my own personal experience and that in no way means yours will be the same, it's the way we share info on here and in the process, hopefully we all learn something. Rex

rob45
12-20-2010, 02:28 PM
My experience is the only way I know of to get it dead on, is with the use of a kiln. So the temps can be controlled specifically where you want them to be and held there for the specific amount of time you want it held there. I know Kilns are expensive, but there is an alternative to the more expensive kilns like EvenHeat and Paragon, both are made for the specific purpose of knifemaking, there is a company called Sugar Creek Industries, they make kilns for pottery and glass, but they also have one for knifemakers, look them up under, Smart Kilns, they aren't priced like the others, mine is about a year and a half old, it's the large knifemakers model and cost me right at $500.00, I don't think that included shipping, but I believe they are in S. Carolina, if I'm not mistaken. As long as you won't need one to HT over 2000 degrees, it's a good choice, and great value for the money.

Sugar Creek Industries is located in Linden, IN.
The line of kilns they manufacture is called "Good Kilns".

Their phone number is (765)339-4641
Ask for Sue. A very nice lady who can steer you in the proper direction.

My ex was an art major and involved with ceramics; this is how I knew this company existed. I bought the "Big Knife Kiln" and picked it up in person; even met the man who actually built the kiln.
The kiln was purchased as a secondary unit for smaller ceramic projects, as the ex already had a larger "Fire Master" kiln.

During the divorce, she kept the Fire Master kiln, and I got the Big Knife kiln. It had never been plugged in, let alone used.
I never got around to wiring for 220 in the new house (will happen this spring), and am still new to the whole process of HT, so the kiln is still unused.
But it seems to be well-designed and well-built, and during pickup they were very eager to help with any questions plus instructions on use.

I cannot comment on shipping costs, but as far as weight is concerned, a middle-aged man with a weak back (me) can easily pick up the Big Knife kiln and move it to another location. The Fire Master kiln owned by my ex weighs well over 200#, maybe closer to 300. They make models both considerably smaller and considerably larger.

What I am saying is this: I cannot (yet) comment on the use of my Big Knife kiln, but I can most definitely vouch for the excellent service provided by Sugar Creek Industries.
I believe BossDog carries this line on his website; if it's good enough for the suppliers, it's certainly good enough for us.

Each kiln is built to order, so check out their line of kilns and research the options. If you don't see what you need, give them a call; they can set you up for any project you can dream up.

http://www.sugarcreekind.com/

http://www.usaknifemaker.com/heat-treat-ovens-and-accessories-sugar-creek-inst-kilns-c-57_116.html

McClellan Made Blades
12-20-2010, 04:00 PM
Sugar Creek Industries is located in Linden, IN.
The line of kilns they manufacture is called "Good Kilns".

Their phone number is (765)339-4641
Ask for Sue. A very nice lady who can steer you in the proper direction.

My ex was an art major and involved with ceramics; this is how I knew this company existed. I bought the "Big Knife Kiln" and picked it up in person; even met the man who actually built the kiln.
The kiln was purchased as a secondary unit for smaller ceramic projects, as the ex already had a larger "Fire Master" kiln.

During the divorce, she kept the Fire Master kiln, and I got the Big Knife kiln. It had never been plugged in, let alone used.
I never got around to wiring for 220 in the new house (will happen this spring), and am still new to the whole process of HT, so the kiln is still unused.
But it seems to be well-designed and well-built, and during pickup they were very eager to help with any questions plus instructions on use.

I cannot comment on shipping costs, but as far as weight is concerned, a middle-aged man with a weak back (me) can easily pick up the Big Knife kiln and move it to another location. The Fire Master kiln owned by my ex weighs well over 200#, maybe closer to 300. They make models both considerably smaller and considerably larger.

What I am saying is this: I cannot (yet) comment on the use of my Big Knife kiln, but I can most definitely vouch for the excellent service provided by Sugar Creek Industries.
I believe BossDog carries this line on his website; if it's good enough for the suppliers, it's certainly good enough for us.

Each kiln is built to order, so check out their line of kilns and research the options. If you don't see what you need, give them a call; they can set you up for any project you can dream up.

http://www.sugarcreekind.com/

http://www.usaknifemaker.com/heat-treat-ovens-and-accessories-sugar-creek-inst-kilns-c-57_116.html



Rob,
My bad with the locale of Sugar Creek, I can't remember why I was thinking they were in S.C., as far as the sizes of kilns, to my knowledge they only offer 2 sizes for knifemakers models, the regular size (about 12-14") and the larger, (around 24" size), I opted for the larger because I knew I would be making larger blades. In an effort to save money I really wanted to go with the smaller one, but I asked my fellow DAWGS on here about it and they said it WOULD save money by getting the bigger unit, because eventually I would either be buying the bigger one or have to send my blades out for HT. A side note about the options, it comes with a basic temp controller, you will have to sit with it, and "babysit" your blade the entire time it is in there, this wasn't a problem for me at first, the ability to be able to get the large kiln and then later buy the computer controller was an added benefit for me, it allowed me to get my kiln, and then save up for the computer control.
Sue is the BOMB!!!!! She is the sweetest customer service person in the world! The entire company is her, her husband and I think 1 maybe 2 other part time people. Her husband handles the kiln building and design, while she maintains the office, small company = personalized service, they are amazing, the controller went out on my kiln a few months back, I called and told them what it did, talked to Sue's husband about it, and he knew what the problem was. Told me what to do, and had me a new part in the mail the same day! Explained how to take it off and put it back on, it was pretty simple anyway, but it's nice to know that he was there in case I needed help! I did finally order the computer control for mine, if it is within your budget, GET IT! It makes all the difference in the world, it is the exact same computer control on the EvenHeat! You made out like a bandit, getting custody of the Big Knife Kiln! And while each kiln is built to order, he is pretty fast getting them built, I can't say enough good things about them, most people are eager to let you know about bad experiences, but with Sue, I don't know if anyone COULD have a bad experience, she is sweet as she can be, she makes everything easy. She'll even let you break up the cost into payments if you ask nicely.

They come prewired for 208, but you can have them wired for 115, I would recommend leaving it at 208, and have a 220 plug put in, on it's on line! I've used my since summer of last year, while electric is slower to get to heat, the control is much better. Do keep in mind that if you take the kiln over 2000 degrees, it will void the warranty, that is the info I got when I got mine, that is one of the reasons I got the computer control, ATS-34, CPM154 (all of these types steels) require a HT around 1950, if your trying to control that by hand, meaning turning the little oven knob back and forth trying to keep the temp right, it's next to impossible if not actually impossible to stay in the target area, with a soak time of 30 minutes, you's go crazy trying to keep it right, without going over 2000 degrees! But like I said, if money is tight you can wait on it, suffer the babysitting and still have a kiln that will get the job done very well, it's an easy compromise! Of course shipping isn't wonderfully priced it is better now since they came up with a safe way to ship them UPS, when you get it, there will be expandable foam all over it inside and out, very well packed, it's a bit of a pain getting it unpackaged, but no problem at all, a lot less of a problem than having a broken kiln!
Boss does carry them, matter of fact when I was ordering my computer control unit, I mentioned to Sue that I had been talking about them on KD, and she said that Tracy applied to become a distributer, I put in a good word for the BOSS (for what it was worth), told her that they couldn't go wrong for their Knifemaking kilns, he would get them more exposure than they've ever had, with his website alone. Because knifemakers use that website all the time, if for nothing other than looking and drooling over the things we...I mean they want. You really can't go wrong with a sugar Creek Kiln, for the money it is the best thing going, do keep in mind it isn't an Even Heat, or a Paragon, those were made for the specific purpose of Knifemaking, so there are some differences. At this point even if I could get a one of the others, I couldn't justify it, mine does the job very well, and I'm extremely happy with it, what else do you need? Rex

LRB
12-29-2010, 01:22 PM
awesome stuff here, i use 1095 and love the stuff. i heard great things about 1084 but i have trouble finding it. i heat to non magnetic with a torch while using a laser thermometer on the opposite side, and quench in a horrible mixture of engine sludge/used diesel oil/fresh trans fluid, i know its a sin. i temper in a large oven and check it with my laser from time to time. my 1095 gets hard as a rock though, if i need to make a small filework change, you can bet one of my files will be destroyed. i like 1095 because i can treat it with normal tools, until i can buy better equiment.

The problem with the file test for hardness, is that it really doesn't tell you anything about the acuall hardness. By your description of your heat treat, I can positively guarantee that you have a good bit of pearlite mixed in with the martensite in your finished blade. That quench mix will not harden 1095 well at all. You are experiencing the file skipping over the martensite, which prevents the file from cutting the pearlite, but you can safely bet that it's there. I can also guarantee that properly HTed 1084 will out cut your blades. To harden 1095 and get max coversion to martensite, requires a quench that brings the temp down from 1475/1500, to under 900 in less than one second, or you get a mix of pearlite with martensite. Only water, or brine will completely do the hardening, but you will lose some blades with it. The best available oil is going to be Parks #50, which does the cooling in just a tad over that one second. Maybe 1.2/1.5 seconds. With the mix you're using, you are maybe, I'm guessing, getting around a 10/12 second cooling at best.