[RCSE] Wetting Carbon Tow.... Photos
Hi Guys ... I've done some trials and I'm nearly there. I decided that I've gone as far as I can without building a complete jig. So far I've made the frame, resin container, ladder guide, and a few of the guide/pinch rolls. I've taken four photos which shows the full assembly to date and some details of the tow wetting tube. I've sent the assembly photo to those that asked but I can send the other three to you if you want ... let me know. I still have to make a top roll, complete the top pinch rolls and make three more rolls for the bottom outlet section. I'm also going to make the air blast for blowing the tow on the way into the resin tube. I'm hoping to complete the jig this weekend. Eddie the Eagle in sunny South Australia RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
Re: [RCSE] Wetting Carbon Tow ....
That is probably the best you can do without going to high modulus carbon. From what I've seen on the net high modulus carbon really only tows made up of smaller diameter carbon fibres. The diameter of a 12 K HM carbon tow is about half that of the normal carbon tow. Physically this means that there can be about 5 X the number of carbon fibres / 1 mm2 of HM laid up carbon The reason for this is that the smaller fibres will be packed closer in the spar giving higher density and therefore higher strength for a spar made of this material. Quoted figures :- Normal carbon diameter of tow = 0.95 mm High Modulus tow = 0.41 mm The Eagle RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
[RCSE] Wetting carbon tow ... a solution ?
Hi Guys to add a little more to this thread I did a little more research on the net, talked to a number of suppliers here in Australia and have come up with a design for a machine to wet out the tows. It will consist of a vertical length of PVC tube of 35mm dia. closed at the bottom with a nylon plug that has been turned to have a taper in the top surface reducing down to a hole just big enough to pass the tow through it with some drag. This pot is filled with resin with the tow passing down through the hole. The tow with its small clearance to the hole will stop the resin running out. The tows would be fully wet out when they are squeezed through the hole in the bottom of the pot.Below this is a pair of rollers that are spring loaded together. The tow as it passes through these rollers has any excess resin wiped off the outside of the tow which drips into another container underneath. This assembly is mounted in a wooden frame and clamped to the bench so that lengths of tow can be pulled through and laid onto plastic on the bench. The tows would be covered with absorbent paper and rolled to get any excess resin out before being placed into the spar jig. It has been suggested that if there was a low pressure supply of air directed at the tow just before it enters the pot of resin the fibres within the tow would be separated a little and would pick up the resin better. I've started to construct this set up today and have made the resin container and part of the support frame. I'm going to try pulling the tow through the pot of resin tonight to see if the inside of the tow is fully wet out. The biggest problem that I see is the cleaning of all the machine after wetting the tows, Obviously the machine will have to be easily disassembled to do this Any comments or suggestions before I go too far ?? Eddie the Eagle in sunny South Australia RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
RE: [RCSE] Wetting carbon tow ... a solution ?
At 14:27 12/09/2005 -0500, you wrote: Eddie, this sounds very professional. I'd like to see a photo of it when you get through with the tool and I'd like to know if it worked as planned/ George Voss We can't send photos to the group but I can certainly send anyone who's interested a photo when it's completed I'll let you know when it's completed. The Eagle RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
Re: [RCSE] Wetting Carbon Tow ....
At 06:51 AM 9/7/05, you wrote: Eddie, I asked Mike Lachowski how they were getting their molded models so light. He did a very in depth write up for me about how he is building them starting with the method of wetting out the tow. Please see below: D Thanks guys, It might be helpful to describe what I had intended to do to make the spars for the model. The wing is foam cored that has been routed out to insert the spar. The spar is going to be pre-made and then inserted into the slot in the core. The spar is tapered from 17mm wide at the root to 8mm at the tip. I am going to make spar caps in a jig that I've constructed and then assemble them with the joiner box and shear webbing in another jig. This will ensure that the depth of the spar is correct to fit the wing. I was intending to make the spar caps with various lengths of tow so that the cap thickness also tapers to the tip. To try to get the tows as straight as possible in the spar cap I intend to use a steel roller to roll the tows into the jig all in one direction after they are laid into the jig. I was intending to wet out the carbon tows with a roller system that will hopefully wet the carbon and leave the carbon both straight and with the correct amount of resin in it. When the cap is all laid up I was going to use peel ply and vacuum bag it in the jig to get any excess resin out of it. It is this roller system that I was trying to find on the net. This is for the Majali model that the Club group is constructing and because we have to make a total of 22 spars we need to have a system of building the spars that will ensure some consistency in size and strength. I would appreciate any comments on both the construction method proposed and any ideas of how to make a carbon tow wetting system. I still can't find the photo that I saw on the net. Eddie the Eagle in sunny South Australia RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
Re: [RCSE] Wetting Carbon Tow ....
There may be a better way. I use precured carbon strips. Available from Avia Sport Composites. Their material is FAR superior to anything that you can make with tow, they are significantly stronger/stiffer/lighter for their relative size. I have several relevant articles on my club web site, under articles www.kcse.us Lee Estingoy Kansas Soaring and Electric Club - Original Message - From: Eddie Smith [EMAIL PROTECTED] To: soaring@airage.com Sent: Wednesday, September 07, 2005 4:14 AM Subject: Re: [RCSE] Wetting Carbon Tow At 06:51 AM 9/7/05, you wrote: Eddie, I asked Mike Lachowski how they were getting their molded models so light. He did a very in depth write up for me about how he is building them starting with the method of wetting out the tow. Please see below: D Thanks guys, It might be helpful to describe what I had intended to do to make the spars for the model. The wing is foam cored that has been routed out to insert the spar. The spar is going to be pre-made and then inserted into the slot in the core. The spar is tapered from 17mm wide at the root to 8mm at the tip. I am going to make spar caps in a jig that I've constructed and then assemble them with the joiner box and shear webbing in another jig. This will ensure that the depth of the spar is correct to fit the wing. I was intending to make the spar caps with various lengths of tow so that the cap thickness also tapers to the tip. To try to get the tows as straight as possible in the spar cap I intend to use a steel roller to roll the tows into the jig all in one direction after they are laid into the jig. I was intending to wet out the carbon tows with a roller system that will hopefully wet the carbon and leave the carbon both straight and with the correct amount of resin in it. When the cap is all laid up I was going to use peel ply and vacuum bag it in the jig to get any excess resin out of it. It is this roller system that I was trying to find on the net. This is for the Majali model that the Club group is constructing and because we have to make a total of 22 spars we need to have a system of building the spars that will ensure some consistency in size and strength. I would appreciate any comments on both the construction method proposed and any ideas of how to make a carbon tow wetting system. I still can't find the photo that I saw on the net. Eddie the Eagle in sunny South Australia RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
[RCSE] Wetting Carbon Tow ....
Guys ... I saw a photo quite some time ago of a jig for wetting out carbon tow for spar caps.I thought that I had saved the photo of the jig but I can't find it.Does anyone know where I might find photos of such a mechanism? Or .. has anyone made something to do this job that they can describe.. Eddie the Eagle in sunny South Australia RCSE-List facilities provided by Model Airplane News. Send subscribe and unsubscribe requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
