---------------------------------------------------------- Pietenpol-List Digest Archive --- Total Messages Posted Wed 05/05/04: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 11:51 AM - cutting carbon fiber layups (Michael D Cuy) 2. 04:51 PM - Re: Piet ride (hjarrett) 3. 06:50 PM - T-88 (Jake Nichols) 4. 07:03 PM - Re: cutting carbon fiber layups (Rcaprd@aol.com) 5. 07:23 PM - Re: T-88 (Jack Phillips) 6. 07:38 PM - Re: Piet ride (Rcaprd@aol.com) 7. 07:45 PM - Re: T-88 (Richard Navratil) 8. 10:03 PM - Re: T-88 (Clif Dawson) ________________________________ Message 1 _____________________________________ Time: 11:51:22 AM PST US From: Michael D Cuy Subject: Pietenpol-List: cutting carbon fiber layups <000c01c42f88$2c514d80$2cc5fea9@home> <010401c42f96$f6183d00$f6ddf6ce@hjarrett> <002d01c42fba$fdfff890$2cc5fea9@home> <001501c43074$00686e00$daddf6ce@hjarrett> --> Pietenpol-List message posted by: Michael D Cuy Dear Pieters, as Corky says.......do any of you guys know how difficult (or easy) it is to cut say a hole, rectangle, etc. into a piece of carbon fiber ? To drill ? This is all layed up and cured. It's under a 1/8" thick, more like a fat 1/16". thanks for helping a guy who tests materials all week on a materials-related question ! Mike C. ________________________________ Message 2 _____________________________________ Time: 04:51:19 PM PST US From: "hjarrett" Subject: Re: Pietenpol-List: Piet ride --> Pietenpol-List message posted by: "hjarrett" The reason you bounce when they don't is the slope of the lift curve. The steeper the slope the harder the bounce. Of course there is no reason to test the Piet airfoil since there is nothing to be learned about Pietenpols and no one should ever consider making any changes to an already "perfect" design. Hank (Running for cover) J ----- Original Message ----- From: "Michael D Cuy" Subject: Pietenpol-List: Piet ride > --> Pietenpol-List message posted by: Michael D Cuy > > Walt-- You are right on about the Piet flying better with another on > board. When I'm solo on a windy/turbulent day I can fly formation with a > Cub or Champ and those guys look like they are enjoying the ride with no > problems. In the mean time I'm bouncing away, all over the place. You > try to explain why you aren't flying on certain days and the other guys > poo-poo it.......but they are not the ones who have to endure the rough > ride. > > Mike C. > > ________________________________ Message 3 _____________________________________ Time: 06:50:00 PM PST US From: "Jake Nichols" Subject: Pietenpol-List: T-88 I am starting my practice project and was wondering a couple of things about T-88. First of all, what is the viscosity of the epoxy after it is mixed in the correct ratio. I was using some and it appeared to be thicker than honey. I was using a butter knife to spread it in a thin layer to laminate some stock together and it took a lot of force to spread into a thin layer. The temp was about 60 F so perhaps the cold had something to do with this. To mix in a 50/50 ratio I would lay beads of the epoxy next to one another and make sure they were the same length and volume. The other question has to do with quality control after joining the parts. During the lamination process, small amounts of the epoxy seeped from between the individual sticks. After 24 hours these seeps were still slightly tacky. When I used my block plane to begin rounding the leading edge, the epoxy was solid and did not cut like it had any elasticity in it. In other words it was not soft, just slightly sticky on the exposed surface. Is this normal or is this a sign of an incorrect mixture? If it is an incorrect mixture, any idea of which part had too great of a volume? If you are wondering about my little project, it is a TEAM/ISON/what ever they call themselves now MiniMax vertical stabilizer. They sell this as a starter kit to allow you to see their plans, constuction techniques and materials. It comes with the wood, T-88, plans and some hardware. Not bad for $30. I thought this would be a good way to get my feet wet before jumping in on a Piet. James Nichols ________________________________ Message 4 _____________________________________ Time: 07:03:19 PM PST US From: Rcaprd@aol.com Subject: Re: Pietenpol-List: cutting carbon fiber layups --> Pietenpol-List message posted by: Rcaprd@aol.com In a message dated 5/5/04 1:52:44 PM Central Daylight Time, Michael.D.Cuy@grc.nasa.gov writes: << Dear Pieters, as Corky says.......do any of you guys know how difficult (or easy) it is to cut say a hole, rectangle, etc. into a piece of carbon fiber ? To drill ? This is all layed up and cured. It's under a 1/8" thick, more like a fat 1/16". >> Mike, I have drilled, and cut, a lot of carbon fiber at work. The Hawker Horizon has a carbon fiber fuselage, and stabilizers. To drill, we use 'com cut' bits (composite cut). They have a small notch at the outer cutting edge of the bit. A regular bit seems to walk, even when you start with a #40 pilot hole. The relief of the bit is a little different, too. A regular bit only lasts about 6 or 7 holes, then it needs re-sharpened. I suggest you step drill it, from #40 bit. Carbon fiber is some Hard stuff !! Our hole saws don't have the normal teeth, but instead are diamond tipped, so they don't wear out so quick. The sabre saw blades are diamond tipped, too. Be very careful about the dust. The fibers it makes are so fine, that they easily get in the pores of your skin, or lungs. You could use normal cutting tools, if you only have one or two holes to do, but be careful not to walk the bit. If you're building a Carbon Fiber Pietenpol, I'm never going to speak to you again !! Chuck G. ________________________________ Message 5 _____________________________________ Time: 07:23:56 PM PST US From: "Jack Phillips" Subject: RE: Pietenpol-List: T-88 Sounds like your T-88 worked about like mine. It is pretty thick, but will flow quite a bit in the 12 hours or so it takes to cure. it is pretty good glue, and does not make the mess that Resorcinol does, but I still prefer resorcinol for structural joints. I used T-88 in places where I didn't have an exact fit, or where the squeezed out glue would show, such as in the cockpit area. Jack Phillips Raleigh, NC -----Original Message----- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of Jake Nichols Subject: Pietenpol-List: T-88 I am starting my practice project and was wondering a couple of things about T-88. First of all, what is the viscosity of the epoxy after it is mixed in the correct ratio. I was using some and it appeared to be thicker than honey. I was using a butter knife to spread it in a thin layer to laminate some stock together and it took a lot of force to spread into a thin layer. The temp was about 60 F so perhaps the cold had something to do with this. To mix in a 50/50 ratio I would lay beads of the epoxy next to one another and make sure they were the same length and volume. The other question has to do with quality control after joining the parts. During the lamination process, small amounts of the epoxy seeped from between the individual sticks. After 24 hours these seeps were still slightly tacky. When I used my block plane to begin rounding the leading edge, the epoxy was solid and did not cut like it had any elasticity in it. In other words it was not soft, just slightly sticky on the exposed surface. Is this normal or is this a sign of an incorrect mixture? If it is an incorrect mixture, any idea of which part had too great of a volume? If you are wondering about my little project, it is a TEAM/ISON/what ever they call themselves now MiniMax vertical stabilizer. They sell this as a starter kit to allow you to see their plans, constuction techniques and materials. It comes with the wood, T-88, plans and some hardware. Not bad for $30. I thought this would be a good way to get my feet wet before jumping in on a Piet. James Nichols ________________________________ Message 6 _____________________________________ Time: 07:38:20 PM PST US From: Rcaprd@aol.com Subject: Re: Pietenpol-List: Piet ride --> Pietenpol-List message posted by: Rcaprd@aol.com In a message dated 5/5/04 6:52:09 PM Central Daylight Time, hjarrett@hroads.net writes: << The reason you bounce when they don't is the slope of the lift curve. The steeper the slope the harder the bounce. >> Hank, Actually, I kind of like the bounce. Keeps me alert, and being at one with the wing, she lets me know about every little anomoliy in the wind, and thermals. I can predict the ride up ahead, by the color of the field. Chuck G. ________________________________ Message 7 _____________________________________ Time: 07:45:46 PM PST US From: "Richard Navratil" Subject: Re: Pietenpol-List: T-88 If you want to make it mix and spread easier, try putting it in the microwave for 10 sec or so. Abit of heat makes it quite thin. It will also reduce your pot life. Dick ----- Original Message ----- From: Jake Nichols To: pietenpol-list@matronics.com Sent: Wednesday, May 05, 2004 8:51 PM Subject: Pietenpol-List: T-88 I am starting my practice project and was wondering a couple of things about T-88. First of all, what is the viscosity of the epoxy after it is mixed in the correct ratio. I was using some and it appeared to be thicker than honey. I was using a butter knife to spread it in a thin layer to laminate some stock together and it took a lot of force to spread into a thin layer. The temp was about 60 F so perhaps the cold had something to do with this. To mix in a 50/50 ratio I would lay beads of the epoxy next to one another and make sure they were the same length and volume. The other question has to do with quality control after joining the parts. During the lamination process, small amounts of the epoxy seeped from between the individual sticks. After 24 hours these seeps were still slightly tacky. When I used my block plane to begin rounding the leading edge, the epoxy was solid and did not cut like it had any elasticity in it. In other words it was not soft, just slightly sticky on the exposed surface. Is this normal or is this a sign of an incorrect mixture? If it is an incorrect mixture, any idea of which part had too great of a volume? If you are wondering about my little project, it is a TEAM/ISON/what ever they call themselves now MiniMax vertical stabilizer. They sell this as a starter kit to allow you to see their plans, constuction techniques and materials. It comes with the wood, T-88, plans and some hardware. Not bad for $30. I thought this would be a good way to get my feet wet before jumping in on a Piet. James Nichols ________________________________ Message 8 _____________________________________ Time: 10:03:45 PM PST US From: Clif Dawson Subject: Re: Pietenpol-List: T-88 <002b01c43313$dba6e680$0600a8c0@laptop> http://www.leevalley.com/garden/page.asp?SID=&page=20009&category=2%2C2070%2C33135&ccurrency=1 The mixing cups shown here are what I use. One thing is that the graduations are on the inside so they disappear in the liquid. I place a strip of masking tape up the side and mark off the level for each component and then fill both in the same cup till the SURFACE level of each matches it's line. Popsicle sticks are used for mixing and spreading. I sand the end off at an angle with the disc sander then sand the face at a long shallow angle until the end is the thickness of fine cardboard. Once you have spread glue on both faces and pressed them together, squeezing out SOME of the glue, enough to know that the two glue surfaces have joined but you still have a film close to the thickness of a piece of paper, then use the fine, angled stick to scrape up the squeeze-out and use that in the next joint. You do not want to clamp this stuff tight! You have to have that film. I bought some 1 and 2 lb pyramid shaped fish weights which I sit on the joint if it is flat as in rib or fuselage side building. Rib gussets may "walk" a bit so go back and check after doing all on a rib and reposition as necessary. It won't be much, if any. You can use tiny brads or staples if you want. Just don't squeeze out too much glue. Glue 3 or 4 test pieces from each batch with the leftovers. When they have cured, break two in shear and examine the faces to see if the wood sheared. If you see glue with only some wood attached you have a problem. I use 3" long 1" X 1" cutoffs for this. Put glue on 1" of each and press together with 2" sticking out each end, one to go in the vice, the other to pull sideways with large pliers until the joint separates. Save and label the other two. Oh, what are you mixing on? Not cardboard or wood I hope. If the link above doesn't work try this one and put 56z82.02 in the left hand "item number" box www.leevalley.com Clif Subject: Re: Pietenpol-List: T-88 If you want to make it mix and spread easier, try putting it in the microwave for 10 sec or so. Abit of heat makes it quite thin. It will also reduce your pot life. Dick Sent: Wednesday, May 05, 2004 8:51 PM Subject: Pietenpol-List: T-88 I am starting my practice project and was wondering a couple of things about T-88. First of all, what is the viscosity of the epoxy after it is mixed in the correct ratio. I was using some and it appeared to be thicker than honey. I was using a butter knife to spread it in a thin layer to laminate some stock together and it took a lot of force to spread into a thin layer. The temp was about 60 F so perhaps the cold had something to do with this. To mix in a 50/50 ratio I would lay beads of the epoxy next to one another and make sure they were the same length and volume. The other question has to do with quality control after joining the parts. During the lamination process, small amounts of the epoxy seeped from between the individual sticks. After 24 hours these seeps were still slightly tacky. When I used my block plane to begin rounding the leading edge, the epoxy was solid and did not cut like it had any elasticity in it. In other words it was not soft, just slightly sticky on the exposed surface. Is this normal or is this a sign of an incorrect mixture? If it is an incorrect mixture, any idea of which part had too great of a volume? If you are wondering about my little project, it is a TEAM/ISON/what ever they call themselves now MiniMax vertical stabilizer. They sell this as a starter kit to allow you to see their plans, constuction techniques and materials. It comes with the wood, T-88, plans and some hardware. Not bad for $30. I thought this would be a good way to get my feet wet before jumping in on a Piet. James Nichols