Return-Path: Sender: (Marvin Kaye) To: lml Date: Mon, 03 Mar 2003 08:35:35 -0500 Message-ID: X-Original-Return-Path: Received: from imo-m04.mx.aol.com ([64.12.136.7] verified) by logan.com (CommuniGate Pro SMTP 4.0.6) with ESMTP id 2042052 for lml@lancaironline.net; Mon, 03 Mar 2003 04:07:51 -0500 Received: from Newlan2dl@aol.com by imo-m04.mx.aol.com (mail_out_v34.21.) id q.1e0.36f565f (3657) for ; Mon, 3 Mar 2003 04:07:44 -0500 (EST) From: Newlan2dl@aol.com X-Original-Message-ID: <1e0.36f565f.2b94755f@aol.com> X-Original-Date: Mon, 3 Mar 2003 04:07:43 EST Subject: composites workbench/ composite materials X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="part1_1e0.36f565f.2b94755f_boundary" X-Mailer: 7.0 for Windows sub 10637 --part1_1e0.36f565f.2b94755f_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Hi Bob I can't say as I have a great workbench design for you but I've built or worked on a lot of them. Basically the more space the better and access to both sides is important. Try and get 16' if you can Width ideally should be 55-60" (most rolls are commonly 50") with drop leaves to increase it to 65"-70" for the occasional odd roll at 60". For the surface, a cutting mat is good but ungodly expensive so what I've found that's reasonably cheap and ideal (i.e. it is self healing, resilient and doesn't dull knives), is industrial linoleum/rubber flooring. We have some grey stuff that's about 6' wide and fabric backed. Works great and can be cut to any length. Normal standing bench height is about 36" for most people. And while you're at it, if you make the flip side from melamine finished particle board, you have the beginning of an EXCELLENT vacuum table flat mold. Or just throw some 4 x 8 sheets on top when you are done cutting and ready to laminate. Melamine finished particle board is cheap, less than $20/sheet as I remember, and it always releases when waxed. Basically it's a Formica finish of particle board. Plus you can gel coat it and end up with a very pleasing texture (just like Formica). So you can laminate directly to it and make flat sheets OR use it for your seal. Just use your vacuum sealant tape and Voila'! You are there. Tempered glass display shelves are also cheap flat molds for smaller parts and when you want a glossy surface. By the way, if you plan on having a vacuum pump, place it in an enclosed area away from the work area. Maybe mount it on wheels so it can be taken outside. Anyway, This is so that you can hear vacuum leaks. You should have a valve and guage, too. Large heavy parts generally are OK with all the vacuum you can get but light laminates may become too dry if you don't back off on the vac. Some folks have also added a "Y" valve if they are doing large parts. This is to attach a shop vac to TEMPORARILY suck down a lot of excess air. Once down, turn off the shop vac and close the valve. This is to make up for the relatively small airflow but high vacuum of a typicall vane driven pump. Try and get a pump that can sustain 25" Hg but I know of some folks that are using old refrigerator pumps for their vacuum. Yet another tip, house insulation scraps (or even aircraft insulationwhich I use) makes for an excellent and cheap breather ply. Otherwise go to a fabric store and get the cheapest quilting batting you can. A great way to store and get your fabric where you need it is to make a rolling "A" frame dolly. What I did for mine was scrounge some old dolly wheels and some odd length exhaust tubing from a car muffler shop and weld an "A" frame dolly for moving fabric. It's got about a 30" wide base and is 64" wide but what made this great (and was affordable), I welded 4 sets of fixed dolly wheels FACING UP and about 1.5" apart. The tube supporting the rolls rested on the upturned dolly wheels and were a cheap bearing system. I put three sets of rollers on each side so that I could hold up to 6 rolls of fabric on the stand at a time. And by having the frame on rollers, you can put it away or where you need it in no time. The next thing is to get some polyethylene tubing from Grainger or a packaging company to cover your rolls of fabric. Slide the poly tube over the rolls and they will stay clean. Plus you can use it for one other thing. It makes a really neat vacuum bag for a lot of parts! I do a lot of boat parts and with one of these bags in the really large size, I could slide a whole mold into the bag, seal the ends and be done! Note this was for a small racing catamaran hull. And I'll give you ONE big suggestion: DO NOT EVER, EVER, EVER LET PEOPLE USE LUBRICANTS AROUND THE COMPOSITES AREA, PARTICULARLY SPRAY LUBES AND MOST ESPECIALLY SPRAY SILICONE!!!!! Needless to say, anyone that's been handling lubricants, sharpening knives with an oil stone, or waxing molds SHOULD NOT handle fabric. You will be fired from Boeing if you are ever caught with a can of spray silicone in the composite shop and for good reason. The stuff is pervasive. Once released, it gets EVERYWHERE! Sure, if somebody on the other end of the hanger sprays some stuff in small amounts on his bicycle chain are you going to throw away a whole part? Probably not but tests run by Boeing showed that it really gets around and should be avoided! There is only ONE way to get the strength values consistent and at the high end and that is to avoid contamination so keep your fabric clean and handle it with clean hands or better yet, with gloves. Last thing is if possible, build an oven. For wet layups, the post cure will give you some extra strength by getting a higher cross link density. And if you REALLY get clever and get a programable thermostat, you can do your own prepregs. As a guess, you can pick it up for about $15 per pound or so if you shop. I found some 250 gr. Hercules IM-7 carbon uni with RS-1 resin from YLA for about that by waiting until the end of a run and picking up an excess roll they had. Of course, if you do prepregs, you need a fridge. I would suggest you do a briefing with your people there and have a familiarization sheet with all the do's and don'ts so that you don't get people ruining some really expensive fabrics. By the way, I don't know if you need any carbon or "S" glass unidirectional but I do have some rolls to sell if you are interested. I worked for a composite company (and have my own boat company) The carbon is standard 33 million modulus material and 12" wide at 4.75 oz/yd^2 and the S glass is also 12". I may also have some intermediate modulus stuff from my racing sailboat but I'd have to check. It's nice stuff at 45 million modulus and 650 ksi tensile. I used about 450 pounds in my boat but I've used what's left of it on the various other projects so I'm not sure what's left. I also have a number of sources for composite supplyers if you need help. I have my own epoxy formulator and the guy is a wiz. Plus he's not even all that expensive and I can help you find excess inventory/odd weight/odd width materials Anyway, I hope this helps. Dan Newland ES #61 --part1_1e0.36f565f.2b94755f_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable Hi Bob

I can't say as I have a great workbench design for you but I've built or wor= ked on a lot of them.  Basically the more space the better and access t= o both sides is important. Try and get 16' if you can  Width ideally sh= ould be 55-60" (most rolls are commonly 50") with drop leaves to increase it= to 65"-70" for the occasional odd roll at 60".  For the surface, a cut= ting mat is good but ungodly expensive so what I've found that's reasonably=20= cheap and ideal (i.e. it is self healing, resilient and doesn't dull knives)= , is industrial linoleum/rubber flooring.  We have some grey stuff that= 's about 6' wide and fabric backed.  Works great and can be cut to any=20= length.

Normal standing bench height is about 36" for most people.  And while y= ou're at it, if you make the flip side from melamine finished particle board= , you have the beginning of an EXCELLENT vacuum table flat mold.  Or ju= st throw some 4 x 8 sheets on top when you are done cutting and ready to lam= inate.  Melamine finished particle board is cheap, less than $20/sheet=20= as I remember, and it always releases when waxed.  Basically it's a For= mica finish of particle board.  Plus you can gel coat it and end up wit= h a very pleasing texture (just like Formica).  So you can laminate dir= ectly to it and make flat sheets OR use it for your seal.  Just use you= r vacuum sealant tape and Voila'!  You are there.  Tempered glass=20= display shelves are also cheap flat molds for smaller parts and when you wan= t a glossy surface.

By the way, if you plan on having a vacuum pump, place it in an enclosed are= a away from the work area.  Maybe mount it on wheels so it can be taken= outside.     Anyway, This is so that you can hear vacuu= m leaks.  You should have a valve and guage, too.  Large heavy par= ts generally are OK with all the vacuum you can get but light laminates may=20= become too dry if you don't back off on the vac.  Some folks have also=20= added a "Y" valve if they are doing large parts.  This is to attach a s= hop vac to TEMPORARILY suck down a lot of excess air.  Once down, turn=20= off the shop vac and close the valve.  This is to make up for the relat= ively small airflow but high vacuum of a typicall vane driven pump.  Tr= y and get a pump that can sustain 25" Hg but I know of some folks that are u= sing old refrigerator pumps for their vacuum.

Yet another tip, house insulation scraps (or even aircraft insulationwhich I= use) makes for an excellent and cheap breather ply.  Otherwise go to a= fabric store and get the cheapest quilting batting you can.

A great way to store and get your fabric where you need it is to make a roll= ing "A" frame dolly.  What I did for mine was scrounge some old dolly w= heels and some odd length exhaust tubing from a car muffler shop and weld an= "A" frame dolly for moving fabric.  It's got about a 30" wide base and= is 64" wide but what made this great (and was affordable), I welded 4 sets=20= of fixed dolly wheels FACING UP and about 1.5" apart.  The tube support= ing the rolls rested on the upturned dolly wheels and were a cheap bearing s= ystem.  I put three sets of rollers on each side so that I could hold u= p to 6 rolls of fabric on the stand at a time.  And by having the frame= on rollers, you can put it away or where you need it in no time.

The next thing is to get some polyethylene tubing from Grainger or a packagi= ng company to cover your rolls of fabric.  Slide the poly tube over the= rolls and they will stay clean.  Plus you can use it for one other thi= ng.  It makes a really neat vacuum bag for a lot of parts!  I do a= lot of boat parts and with one of these bags in the really large size, I co= uld slide a whole mold into the bag, seal the ends and be done!  Note t= his was for a small racing catamaran hull.

And I'll give you ONE big suggestion:  DO NOT EVER, EVER, EVER LE= T PEOPLE USE LUBRICANTS AROUND THE COMPOSITES AREA, PARTICULARLY SPRAY LUBES= AND MOST ESPECIALLY SPRAY SILICONE!!!!!  Needless to say, anyo= ne that's been handling lubricants, sharpening knives with an oil stone, or=20= waxing molds SHOULD NOT handle fabric.

You will be fired from Boeing if you are ever caught with a can of spray sil= icone in the composite shop and for good reason.  The stuff is pervasiv= e.  Once released, it gets EVERYWHERE!  Sure, if somebody on the o= ther end of the hanger sprays some stuff in small amounts on his bicycle cha= in are you going to throw away a whole part?  Probably not but tests ru= n by Boeing showed that it really gets around and should be avoided! There i= s only ONE way to get the strength values consistent and at the high end and= that is to avoid contamination so keep your fabric clean and handle it with= clean hands or better yet, with gloves.

Last thing is if possible, build an oven.  For wet layups, the post cur= e will give you some extra strength by getting a higher cross link density.&= nbsp; And if you REALLY get clever and get a programable thermostat, you can= do your own prepregs.  As a guess, you can pick it up for about $15 pe= r pound or so if you shop.  I found some 250 gr. Hercules IM-7 carbon u= ni with RS-1 resin from YLA for about that by waiting until the end of a run= and picking up an excess roll they had.  Of course, if you do prepregs= , you need a fridge.

I would suggest you do a briefing with your people there and have a familiar= ization sheet with all the do's and don'ts so that you don't get people ruin= ing some really expensive fabrics.

By the way, I don't know if you need any carbon or "S" glass unidirectional=20= but I do have some rolls to sell if you are interested.  I worked for a= composite company (and have my own boat company) The carbon is standard 33=20= million modulus material and 12" wide at 4.75 oz/yd^2 and the S glass is als= o 12".  I may also have some intermediate modulus stuff from my racing=20= sailboat but I'd have to check.  It's nice stuff at 45 million modulus=20= and 650 ksi tensile.  I used about 450 pounds in my boat but I've used=20= what's left of it on the various other projects so I'm not sure what's left.=

I also have a number of sources for composite supplyers if you need help.&nb= sp; I have my own epoxy formulator and the guy is a wiz.  Plus he's not= even all that expensive and I can help you find excess inventory/odd weight= /odd width materials

Anyway, I hope this helps.

Dan Newland

ES #61 --part1_1e0.36f565f.2b94755f_boundary--