Original Posted By: "Gordon Bowen"
Please, whoever it was, would you send that message with the instructions re using electrical clamps to hold wires while nicoing them. I had it and I accidently deleted it, and I want it.Thanks.Bill Weir ________________________________________________________________________________
Pietenpol-List: Re: Pietenpol-List Digest: 9 Msgs - 08/14/07
Re: Re: Pietenpol-List: Adhesives article
Original Posted By: AMsafetyC(at)aol.com
You guys are welcome. Been posting to the Rutanesque homebuilder webgroup for some time about these issues. Couple of handling tips about epoxies. 1) they never reach 100% full cure, but tend to max out when given time 30 days min., at 77F. The can be post cured up to about 150F to reach 100% crosslinking, therefore eliminate deformation on hot days on flightline. But the plane is an entire system, so the epoxy is only part of the solution and problem., 2) if you have problems with gap filling and/or runouts of the glue, use microballons to "bulk-up" and then a pinch of cotton flox or silica to eliminate sag of the glue before curing. The flox and silica are thixotropes, kinda like long fibers under a microscope, this gives thickening without much bulk, and some added bonding strength. The microballons are jus little round balls, they just give lighter bulkier bonds without thickening. The glue has to be runny enough to saturate the wood fibers but thickened enough to not run-out to much. T-88 is chemically thickened, that's why most people like it. But you can use a runny West System or Hexcel or mfgers stuff and thicken it yourself cheaply. Flox, ballons and silica are all available from Aspruce or Wicks. Lastly- keep the mix ratio required by the mfger right on the money. Don't guess or estimate. Any excess epoxy or curative is just a waste and lessens the overall physical properties of the mixed system. I use a cheap postal scale that has grams and oz's. If you decide to use the dispensing pumps available from some mfgers, make very sure the nozzles are clean. These pumps are only accurate when the nozzles are keep clean of residue. The hardener has a tendency to get plugged up due to the amines in the hardener reacting with the moisture in the air. Hope this helpful, and not preachy.Gordon ----- Original Message -----
You guys are welcome. Been posting to the Rutanesque homebuilder webgroup for some time about these issues. Couple of handling tips about epoxies. 1) they never reach 100% full cure, but tend to max out when given time 30 days min., at 77F. The can be post cured up to about 150F to reach 100% crosslinking, therefore eliminate deformation on hot days on flightline. But the plane is an entire system, so the epoxy is only part of the solution and problem., 2) if you have problems with gap filling and/or runouts of the glue, use microballons to "bulk-up" and then a pinch of cotton flox or silica to eliminate sag of the glue before curing. The flox and silica are thixotropes, kinda like long fibers under a microscope, this gives thickening without much bulk, and some added bonding strength. The microballons are jus little round balls, they just give lighter bulkier bonds without thickening. The glue has to be runny enough to saturate the wood fibers but thickened enough to not run-out to much. T-88 is chemically thickened, that's why most people like it. But you can use a runny West System or Hexcel or mfgers stuff and thicken it yourself cheaply. Flox, ballons and silica are all available from Aspruce or Wicks. Lastly- keep the mix ratio required by the mfger right on the money. Don't guess or estimate. Any excess epoxy or curative is just a waste and lessens the overall physical properties of the mixed system. I use a cheap postal scale that has grams and oz's. If you decide to use the dispensing pumps available from some mfgers, make very sure the nozzles are clean. These pumps are only accurate when the nozzles are keep clean of residue. The hardener has a tendency to get plugged up due to the amines in the hardener reacting with the moisture in the air. Hope this helpful, and not preachy.Gordon ----- Original Message -----
Re: *****SPAM***** Pietenpol-List: Adhesives article
Original Posted By: "Glenn W. Thomas"
Subject: Re: *****SPAM***** Pietenpol-List: Adhesives article
Subject: Re: *****SPAM***** Pietenpol-List: Adhesives article
RE: Pietenpol-List: Adhesives article
Original Posted By: owner-pietenpol-list-server(at)matronics.com
The only thing that throws me with the TiteBond type glues is joint slippageon a flat plane under tension. All these glues do have slippage and some areworse than others. The easiest way to get them to slip is put them undertension and let them get warm. A guitar neck is an excellent example. Overthe course of 30 years, neck warpage occurs as a result of 2200 lbs pressureat room temp causing the fingerboard joint to slip on the underlying neck.It's the primary reason that most guitar necks have a truss rod built in.I'll grant that all the glues tested are sensitive to strain and heat (andeven humidity in some cases) but it's a big problem for hide and whiteglues.The particular place on an airplane where this slippage seems most likely tooccur is on the scarf joint of a two piece spar.Opinions?Greg Chapmanhttp://www.mousetrax.comhttp://www.layer1wireless.com"Don't start with me or I'llreplace you with a small andefficient script!"
The only thing that throws me with the TiteBond type glues is joint slippageon a flat plane under tension. All these glues do have slippage and some areworse than others. The easiest way to get them to slip is put them undertension and let them get warm. A guitar neck is an excellent example. Overthe course of 30 years, neck warpage occurs as a result of 2200 lbs pressureat room temp causing the fingerboard joint to slip on the underlying neck.It's the primary reason that most guitar necks have a truss rod built in.I'll grant that all the glues tested are sensitive to strain and heat (andeven humidity in some cases) but it's a big problem for hide and whiteglues.The particular place on an airplane where this slippage seems most likely tooccur is on the scarf joint of a two piece spar.Opinions?Greg Chapmanhttp://www.mousetrax.comhttp://www.layer1wireless.com"Don't start with me or I'llreplace you with a small andefficient script!"
Re: Pietenpol-List: Adhesives article
Original Posted By: Greg Chapman
You have just perfectly decribed shear stress and thermoplastic flow of a apparent thermoset resin. The adhesive is very slowly flowing to relieve the strain and as the temp rises with the adhesive under shear strain the adhesive flows faster to relieve the strain, thus bond failure. A formlator chemist would change the formula to increase the amount of chemical cross-linking at room temp and then post cure the mixed resin laminate to a temp about 15F above the highest temp it would see in it's application. The laminate would still creep but not until the laminate saw a temp about 25F above the post temp. Below this post cure temp there would be no creep, the resin would truely be thermoset. The formula that gave higher amounts of crosslinking would also produce more exothermic reaction at room temp, therefore the laminate would creep less due to this increase of reaction temp. Problem with higher amount of crosslinking is also shorter pot life.GordonGordon ----- Original Message -----
You have just perfectly decribed shear stress and thermoplastic flow of a apparent thermoset resin. The adhesive is very slowly flowing to relieve the strain and as the temp rises with the adhesive under shear strain the adhesive flows faster to relieve the strain, thus bond failure. A formlator chemist would change the formula to increase the amount of chemical cross-linking at room temp and then post cure the mixed resin laminate to a temp about 15F above the highest temp it would see in it's application. The laminate would still creep but not until the laminate saw a temp about 25F above the post temp. Below this post cure temp there would be no creep, the resin would truely be thermoset. The formula that gave higher amounts of crosslinking would also produce more exothermic reaction at room temp, therefore the laminate would creep less due to this increase of reaction temp. Problem with higher amount of crosslinking is also shorter pot life.GordonGordon ----- Original Message -----
Re: Pietenpol-List: Re: Pietenpol-List Digest: 9 Msgs - 08/14/07
Original Posted By: "Bill Weir"
Bill,Wish I knew the correct name for the clamp. It is used by electricans, ususally when attaching a smaller wire to a larger wire and can be bought at any electrical supply store (about a buck). It is made of copper and is U shaped. It comes in a number of different sizes. The two legs of the U are threaded and has a nut that will force a wedge toward the bottom of the U which acts as a clamp. Being made of copper, it will not damage the cable. I used a 1/8" clamp for my 1/8th" cable.I put the nicopress sleeve on the cable, wrapped the cable around the thimble and back into the sleeve. I then placed the clamp directly behind the sleeve, pulled the cable tight around the thimble and closed the clamp. That way you can not only check your over all length of your made up cable but the clamp servers to hold the sleeve in place while you crush it.I just did what I should have done before I ever wrote the first msg. I called a supply store and found out the name. It's called a SPLIT BOLT. Duh.......Gene- Original Message -----
Bill,Wish I knew the correct name for the clamp. It is used by electricans, ususally when attaching a smaller wire to a larger wire and can be bought at any electrical supply store (about a buck). It is made of copper and is U shaped. It comes in a number of different sizes. The two legs of the U are threaded and has a nut that will force a wedge toward the bottom of the U which acts as a clamp. Being made of copper, it will not damage the cable. I used a 1/8" clamp for my 1/8th" cable.I put the nicopress sleeve on the cable, wrapped the cable around the thimble and back into the sleeve. I then placed the clamp directly behind the sleeve, pulled the cable tight around the thimble and closed the clamp. That way you can not only check your over all length of your made up cable but the clamp servers to hold the sleeve in place while you crush it.I just did what I should have done before I ever wrote the first msg. I called a supply store and found out the name. It's called a SPLIT BOLT. Duh.......Gene- Original Message -----
Re: Pietenpol-List: Re: Pietenpol-List Digest: 9 Msgs - 08/14/07
Original Posted By: "Gene & Tammy"
The name you are looking for is Split Bolt. Also is there is Piets around the LaCross, WI I will be there next week for a couple of days.Chet----- Original Message -----
The name you are looking for is Split Bolt. Also is there is Piets around the LaCross, WI I will be there next week for a couple of days.Chet----- Original Message -----
> Pietenpol-List: Re: Pietenpol-List Digest: 9 Msgs - 08/14/07
Original Posted By: "Albert Lowe"
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