KR> Epoxy
Dan, I used Aeropoxy with both fiberglass and carbon fiber layups and it wets out easily now matter which type of cloth I was using. There's very little odor and using acetone to clean brushes it stops the cure in the brushes right away so I can use the brushes again. I would highly recommend the Aeropoxy. Others may have different results using other systems. Neal Hornung (lt1corvette at earthlink.net) -Original Message- >From: Dan Prichard >Sent: Oct 30, 2013 12:18 AM >To: KR List >Subject: KR> Epoxy > >T-88 appears to be the structural adhesive of choice but what about lay up >resins. System 3, west, aeropoxy or what? I can use a little help from >experience. Also I asked about Okome plywood usage. No responses. > >Sent from my iPhone >___ >Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. >To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org >please see other KRnet info at http://www.krnet.org/info.html >see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change >options
KR> .KR BAD REP?
If this aircraft has such a bad rep as the previous mentioned then why have so many been built and as a new owner should I be a bit concerned? I have previously owned and did the testing on a Sonerai 2 . The .KR 2 seems like a good step from there. Doran .kr2owner at gmail.com
KR> Michigan K R 2's
Just putting out a second enquiry here. After the first inquiry I met a person named Harold and went down to the Kalamazoo area to view his aircraft is under construction and it is a beautiful machine! And will be when it is finished! He and his wife are first rate people! Now I am wondering are there any other KR 2 aircraft in Michigan that are flying? Other than my 186 RC? Is there a specific search I can do to find this out mark I am Not all that computer savvy. Thank you! .kr2owner at gmail.com
KR> .KR BAD REP?
The plane really has no bad rep. It is usually the workmanship in the building and/or the flying skills of the pilots that come under question. Many of us often critique the KR but our remarks inadvertently come off as disparaging. Please do not lose sight of the fact that the KR is a great aircraft in the original form and again better with the many mods. -Original Message- From: Doran Jaffas Sent: Wednesday, October 30, 2013 5:59 AM To: krnet at list.krnet.org Subject: KR> .KR BAD REP? If this aircraft has such a bad rep as the previous mentioned then why have so many been built and as a new owner should I be a bit concerned? I have previously owned and did the testing on a Sonerai 2 . The .KR 2 seems like a good step from there. Doran .kr2owner at gmail.com ___ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options
KR> Epoxy
I will swear by West Systems Epoxies simply because I have suffered no physical problems with it. I have had severe skin rashes with other systems. Otherwise I cannot say if one brand is superior to another. I have used West system layups to make fuel tanks, layup on/over urethanes and Styrofoam and woods. I have never had the opportunity to revisit one of my projects the was more than 8 years old so I cannot vouch for longevity. -Original Message- From: Dan Prichard Sent: Wednesday, October 30, 2013 12:18 AM To: KR List Subject: KR> Epoxy T-88 appears to be the structural adhesive of choice but what about lay up resins. System 3, west, aeropoxy or what? I can use a little help from experience. Also I asked about Okome plywood usage. No responses. Sent from my iPhone ___ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options
KR> Epoxy
Dan Prichard wrote: >T-88 appears to be the structural adhesive of choice but what about lay up resins. System 3, west, aeropoxy or what? I second the Aeropoxy recommendation, but others are just as devoted to West, so apparently you can't go wrong with either one of those. Some folks like West for the pump system. I don't see how that could possibly be accurate for small batches (like an ounce or two), but to each his own. I prefer to weigh my Aeropoxy proportions to the gram, which is easy and accurate with a $10 digital scale that weighs up to 11 pounds (will send link tonight). And yes, T-88 is the structural epoxy of choice. Mark Langford, Harvest, AL ML at N56ML.com www.N56ML.com
KR> Epoxy
I honestly believe that structurally there is little difference whether it is T-88, West system, MAS, System3 etc.West system has been used for years in the Marine industry with complex layups of wood and plywood in a pretty brutal environment. I would think that if one were to do the analysis of structural loads on a sailboat with the Wind load, mast stay loads, and wave pounding for days on end Well you get the idea. West system was used by the Gudgeon Brothers in Michigan to make propellers for a NASA wind tunnel project. So I would not be concerned with using any of the previously mentioned to do structural work for a KR. If you want to do a detailed analysis of West properties you can look up the Gudgeon Brothers on boat construction. Regards, Michael On Wed, Oct 30, 2013 at 7:58 AM, Mark Langford wrote: > Dan Prichard wrote: > > >T-88 appears to be the structural adhesive of choice but what about lay up > resins. System 3, west, aeropoxy or what? > > I second the Aeropoxy recommendation, but others are just as devoted to > West, so apparently you can't go wrong with either one of those. Some > folks > like West for the pump system. I don't see how that could possibly be > accurate for small batches (like an ounce or two), but to each his own. I > prefer to weigh my Aeropoxy proportions to the gram, which is easy and > accurate with a $10 digital scale that weighs up to 11 pounds (will send > link tonight). > > And yes, T-88 is the structural epoxy of choice. > > Mark Langford, Harvest, AL > ML at N56ML.com > www.N56ML.com > > > > ___ > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org > please see other KRnet info at http://www.krnet.org/info.html > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options >
KR> Michigan K R 2's
At 06:00 AM 10/30/2013, you wrote: >Now I am wondering are there any other KR 2 aircraft in Michigan that >are flying? + http://registry.faa.gov/aircraftinquiry/AcftRef_Results.aspx?Mfrtxt=&Modeltxt=KR2&PageNo=1 then pick out Michigan
KR> Epoxy
I recommend EZPoxy although most people that have not tried it use West or Aeropoxy. If you check my name and epoxy in the archives you will find a comparison that I did a few years ago. Original Message Subject: KR> Epoxy From: Dan Prichard List-Post: krnet@list.krnet.org Date: Tue, October 29, 2013 9:18 pm To: KR List T-88 appears to be the structural adhesive of choice but what about lay up resins. System 3, west, aeropoxy or what? I can use a little help from experience. Also I asked about Okome plywood usage. No responses. Sent from my iPhone ___ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options
KR> .KR BAD REP?
Go for it, Virg On 10/30/2013 5:59 AM, Doran Jaffas wrote: > If this aircraft has such a bad rep as the previous mentioned then why have > so many been built and as a new owner should I be a bit concerned? I have > previously owned and did the testing on a Sonerai 2 . The .KR 2 seems like > a good step from there. >Doran >.kr2owner at gmail.com > ___ > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org > please see other KRnet info at http://www.krnet.org/info.html > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options >
KR> Epoxy
I have found and reprinted my epoxy comparison below. I think I did one with Aeropoxy also at some point, but could not find it. Surprising to me that nobody else has ever reported a comparison or commented on mine. I really would like to hear comments from others that have used different epoxies. I guess most people use what they use and don't see a need to try something different. from 5/31/08 post We have had a lot of discussions on this list in the past about which epoxy is best. 99% of the posts are usually from people that like the epoxy that they are using and they have not tried anything else. I had always used EZ Poxy in the past and was in that same boat. For the past few days I have been using West System epoxy and I can finally make a comparison between the two. They are both very low odor and pleasant to work with. Viscosity is pretty similar, they both seem to wet out the cloth about the same, and they both get real thin and wet out cloth better when heated with a heat gun. Mixing with micro or flox and sanding are about the same. They can both be used with different hardeners for faster or slower drying. I have used the EZ in cold and hot weather with great results, but have only used the West in fairly warm weather. EZ Poxy is $112 for a 1.5 gallon kit. West is about 23% more expensive at $122 for a 1.26 gallon kit. Looking at the specifications at: http://www.aircraftspruce.com/catalog/cmpages/ezpoxy.php http://westsystem.com/ under the physical properties tab EZ Poxy is about 4% lighter and has about 4% higher tensile strength not post cured. West does not show a tensile strength when post cured. I don't know if that means that they just don't publish it or if it does not get any stronger with post curing. From searching the net I am fairly certain that West is not able to be post cured. The EZ Poxy is nearly 20% stronger if post cured. EZ Poxy will handle heat better when not post cured and much better when post cured. As far as working with them, I like the EZ Poxy better for several reasons. The mix ratio for the EZ Poxy is about one part resin to a half part hardener. West is five parts resin to one part hardener. Weather mixing by volume or weight you can get more precision on your hardener ratio when there is more hardener used, especially on very small batches like I mix a lot of. West has the pumps, but I do it on a scale because you have much better control of how much you mix when you don't need to use full pumps and can do it by the gram. I often hit my layups with a heat gun to make the resin flow better and sometimes to dry them faster. I never had to worry about getting the EZ Poxy too hot, but the West could be overheated pretty easily. I have also a lot of times with the EZ fairly hard, but still a little tacky been able to heat an area some to get it a little soft, bend it as needed, and held it there a few minutes till it cooled and stayed in the new position. With the West it would not bend and would turn white and separate the resin from the fibers. When trimming cured layups I found that the West would tend to have the glass ends fray and come out of the matrix much easier than with the EZ, especially if you cut rapidly with a cutting wheel and got it hot. Some areas even delaminated a little when doing rough cuts and cutting fast. EZ poxy is a brown color and West is clear. A lot of times when I finish a layup with the EZ Poxy I will put it out in the sun and it will heat up and dry faster. I also put dried parts in the sun to post cure some. West would heat up with a carbon layup, but it never gets warm with just white fiberglass. So to sum it up, West is good, but I can't find anything about it that I like better than the EZ Poxy and there are a lot of things about the EZ that I like better. To be fair I guess there are two things about the West that are better, being clear if you wanted to do an unfinished carbon layup instrument panel it would be best, and it is available at local boating stores if you run out on a Saturday. Other's comments are certainly welcome. Brian Kraut Engineering Alternatives, Inc. www.engalt.com Original Message Subject: Re: KR> Epoxy From: List-Post: krnet@list.krnet.org Date: Wed, October 30, 2013 6:03 am To: "KRnet" I recommend EZPoxy although most people that have not tried it use West or Aeropoxy. If you check my name and epoxy in the archives you will find a comparison that I did a few years ago. change options
KR> Epoxy
You are correct. There isn't much difference between room temperature cured epoxy resins. The curing agents make a lot of difference in viscosity and pot life. The differences start to show up when you get into autoclaves and heated cures. There is difference between epoxy adhesives...mainly due to what the filler is...and there have been a lot of unsuccessful attempts to find a filler as good as asbestos. Basically, find a resin system you are comfortable using and stick with it. I am currently using a system from u.s. composites that I really like...it's their name brand but it is probably made by the same company that makes aeropoxy and/or west system. On Oct 30, 2013 7:36 AM, "Michael Lineback" wrote: > I honestly believe that structurally there is little difference whether it > is T-88, West system, MAS, System3 etc.West system has been used > for years in the Marine industry with complex layups of wood and plywood in > a pretty brutal environment. I would think that if one were to do the > analysis of structural loads on a sailboat with the Wind load, mast stay > loads, and wave pounding for days on end Well you get the idea. > West system was used by the Gudgeon Brothers in Michigan to make > propellers for a NASA wind tunnel project. So I would not be concerned > with using any of the previously mentioned to do structural work for a KR. > > > If you want to do a detailed analysis of West properties you can look up > the Gudgeon Brothers on boat construction. > > Regards, > > Michael > > > On Wed, Oct 30, 2013 at 7:58 AM, Mark Langford wrote: > > > Dan Prichard wrote: > > > > >T-88 appears to be the structural adhesive of choice but what about lay > up > > resins. System 3, west, aeropoxy or what? > > > > I second the Aeropoxy recommendation, but others are just as devoted to > > West, so apparently you can't go wrong with either one of those. Some > > folks > > like West for the pump system. I don't see how that could possibly be > > accurate for small batches (like an ounce or two), but to each his own. > I > > prefer to weigh my Aeropoxy proportions to the gram, which is easy and > > accurate with a $10 digital scale that weighs up to 11 pounds (will send > > link tonight). > > > > And yes, T-88 is the structural epoxy of choice. > > > > Mark Langford, Harvest, AL > > ML at N56ML.com > > www.N56ML.com > > > > > > > > ___ > > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org > > please see other KRnet info at http://www.krnet.org/info.html > > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to > change > > options > > > ___ > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org > please see other KRnet info at http://www.krnet.org/info.html > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options >
KR> Epoxy
Brian et al I use West System on most of my projects exclusively, as they are marine related and the boat store is a 1 mile away. However, what you state about the West is true and now that the Canadian Aircraft Spruce is only a 1/2 hour away I will try some EZ and T-88. How do you get around 'post curing' when the application is large - and you don't have hot outside weather to post cure? Is it still strong enough without the post cure for KR work? What would be the better choice for large lay-ups (KR wings etc) that can't be 'post cured'? Gary - Canada -Original Message- From: brian.kraut at eamanufacturing.com Sent: Wednesday, October 30, 2013 9:12 AM To: KRnet Subject: Re: KR> Epoxy I have found and reprinted my epoxy comparison below. I think I did one with Aeropoxy also at some point, but could not find it. Surprising to me that nobody else has ever reported a comparison or commented on mine. I really would like to hear comments from others that have used different epoxies. I guess most people use what they use and don't see a need to try something different.
KR> Post curing wings
It can be done with a few simple tools and some ingenuity. You'll need some 4x8 construction foam panels (the 1" pink stuff works well), a couple of heat guns and an oven thermometer. Build a box of the foam panels big enough to hold a wing section, suspend the wing section from the top and place a heat gun at each of the box (pointing well away from the wing section). I suspended each heat gun on a wire at the ends of the box with the nozzle pointing toward the middle of the box. I put the thermometer pickup in the middle, just below the bottom surface of the wing. With the foam box closed up, it took about 10 minutes for the temperature to register 150 degrees. I wanted to cure the wing at that temperature for at least an hour. If the temperature got over 150, I opened the end of the box to let in a little cool air. I seemed to work well. You can go on the KRSuper2 web site and look in section 5 of the manual to see some pictures of how Scott Watts did his wing. Dave McCauley
