I'm making a tail section
- Thread starter billyp
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Re: I'm building a tail section
Imwould make a seat pan at the same time. Much easier and you won't have to worry about attaching your fiberglass to a seat pan later.
With your shape, you couldn't use a mold if you wanted to. It would never come out unless it was a 2 piece. I don't know if that florist foam would dissolve in acetone, but try a small piece. If it does, you can melt the foam out when done. If it does, you need to make sure that you cover the foam with tin foil or clear packing tape to make sure it dosnt dissolve when applying the resin.
Imwould make a seat pan at the same time. Much easier and you won't have to worry about attaching your fiberglass to a seat pan later.
With your shape, you couldn't use a mold if you wanted to. It would never come out unless it was a 2 piece. I don't know if that florist foam would dissolve in acetone, but try a small piece. If it does, you can melt the foam out when done. If it does, you need to make sure that you cover the foam with tin foil or clear packing tape to make sure it dosnt dissolve when applying the resin.
billyp
Been Around the Block
Re: I'm building a tail section
Bikes not going to have a seat pan
I was just stating the no mold part because J-rod is laying INSIDE a mold, I'm not using one, so I'll be laying around the OUTSIDE of the foam and I just wanted to see if his process of lay up would work the same. Acetone doesn't melt floral foam so I'll be chipping it out...no biggie. I'll double check with the epoxy and foam interaction but I'm pretty sure it won't melt it
Bikes not going to have a seat pan
I was just stating the no mold part because J-rod is laying INSIDE a mold, I'm not using one, so I'll be laying around the OUTSIDE of the foam and I just wanted to see if his process of lay up would work the same. Acetone doesn't melt floral foam so I'll be chipping it out...no biggie. I'll double check with the epoxy and foam interaction but I'm pretty sure it won't melt it
Re: I'm building a tail section
just use tha lamintaing resin it is like trying to hold onto a greased pig other wise when laying up an outside deal like you have
and the laminating resin allows you to pretty easily fit outside corners esp if you lay some light rabric
100% mat is a cheapo quick way to make a weak heavy part
just use tha lamintaing resin it is like trying to hold onto a greased pig other wise when laying up an outside deal like you have
and the laminating resin allows you to pretty easily fit outside corners esp if you lay some light rabric
100% mat is a cheapo quick way to make a weak heavy part
billyp
Been Around the Block
Re: I'm building a tail section
Thanks for the input everyone. Sometimes there's no other way to do it than to just do it!
I'm not 100% happy with the shape so I'll spend the next couple of days staring at it and refining it, definitely need to get the tank on to see if it flows. Then plan to glass it on Friday!
More pics to come
Thanks for the input everyone. Sometimes there's no other way to do it than to just do it!
I'm not 100% happy with the shape so I'll spend the next couple of days staring at it and refining it, definitely need to get the tank on to see if it flows. Then plan to glass it on Friday!
More pics to come
Re: I'm building a tail section
do some practice with the laminating resin on some odd shaped pieces you will learn yourself the process done RIGHT
but do not try to lay it wet that is terrible advice and TOTALLY the backwards way to lay up an outside form
and using only mat is the same as if it were chopper-gunned( a shitty weak part)
start out by painting on a layer of resin,let it cure then a single cloth layer,after the lay fill with another coast of resin,let it cure repeat until you have a few layers,you can even add a layer of mat to gain some thicknes and distance between lays which increases rigidity but this will tend to make your final be wavy looking needing filler
do some practice with the laminating resin on some odd shaped pieces you will learn yourself the process done RIGHT
but do not try to lay it wet that is terrible advice and TOTALLY the backwards way to lay up an outside form
and using only mat is the same as if it were chopper-gunned( a shitty weak part)
start out by painting on a layer of resin,let it cure then a single cloth layer,after the lay fill with another coast of resin,let it cure repeat until you have a few layers,you can even add a layer of mat to gain some thicknes and distance between lays which increases rigidity but this will tend to make your final be wavy looking needing filler
Re: I'm building a tail section
Could you clarify please? No seat pan. Does that mean you are only making tail section architecture? Even so, consider constructing the base or mounting structure - whatever that is in your design - first. I have done rather a lot of this sort of thing, and always build the structural part - the part that actually has to work - first. Usually (invariably?) takes vastly longer and is far more complex than the cosmetic element. Once the foundation is sorted out, the rest is almost trivially simple. It is certainly possible to spend a lot of time agonizing over the aesthetics, but the actual execution is usually straight forward. The mechanics - mountings -hinging - vibration dampening-etc-etc very often are not. Even worse, if you do the body work first, you will likely have to make the mechanical elements work around what you have already built - not generally very good engineering, and usually means having to accept less than ideal design.
You can use any level of complexity in the moldless construction you are intending. Is there a reason you need to remove the interior foam? Regardless, you can easily scrape it out as long as you can pick at it with something. Florists foam is pretty light, so it isn't too dreadful to leave if you are not racing. I generally use urethane foam, but have used florists foam often enough and it is impervious to the epoxies I use. I doubt if polyester eats it ether. Virtually everything I build is one-off, and as there is sort of an intent to not make duplicates, molds are pretty uncommon for me, but for the record, I do have a mold or two for the really severely complex things (most recently a seat pan) because of the insane hours needed to create the original.
Could you clarify please? No seat pan. Does that mean you are only making tail section architecture? Even so, consider constructing the base or mounting structure - whatever that is in your design - first. I have done rather a lot of this sort of thing, and always build the structural part - the part that actually has to work - first. Usually (invariably?) takes vastly longer and is far more complex than the cosmetic element. Once the foundation is sorted out, the rest is almost trivially simple. It is certainly possible to spend a lot of time agonizing over the aesthetics, but the actual execution is usually straight forward. The mechanics - mountings -hinging - vibration dampening-etc-etc very often are not. Even worse, if you do the body work first, you will likely have to make the mechanical elements work around what you have already built - not generally very good engineering, and usually means having to accept less than ideal design.
You can use any level of complexity in the moldless construction you are intending. Is there a reason you need to remove the interior foam? Regardless, you can easily scrape it out as long as you can pick at it with something. Florists foam is pretty light, so it isn't too dreadful to leave if you are not racing. I generally use urethane foam, but have used florists foam often enough and it is impervious to the epoxies I use. I doubt if polyester eats it ether. Virtually everything I build is one-off, and as there is sort of an intent to not make duplicates, molds are pretty uncommon for me, but for the record, I do have a mold or two for the really severely complex things (most recently a seat pan) because of the insane hours needed to create the original.
billyp
Been Around the Block
Re: I'm building a tail section
I digress, there IS a seat pan, there kind of has to be in order to have and mount a seat. I should have said I'm not using a traditional seat pan that attaches in the traditional way. All of the mounting and positioning have been worked out, a crude mock up has been made and a more reformed model that a mold will be taken from is in the works as we speak. The mold will be used to make a carbon fiber seat pan and mounting system. I'm keeping it close to the vest because if it works it'll be pretty cool, but also functional, if it doesn't work, back to the drawing board and a more traditional seat pan. Everything that you've said has been taken into account including first and foremost safety! No matter how cool it looks, I will not use it if it's not safe. In the end I will be riding this bike and it has to be safe. The seat pan that I plan will be solidly mounted to the frame both front and back. The main purpose of the tail section is to hide the mounting plate (steel) that will be welded to the frame and also to hide battery. All I can say is stay tuned, once I get it further along I would be happy to have you all examine and tear it apart if it's not safe. I value the input on this site, for the most part, there is a lot of knowledge and a lot of people with WAY more skill than me.
Mounting of the tail section and the "seat pan" have all been figured out, now it's just a matter of doing it and doing it safely...but bad assilly
Foam needs to be removed because my battery and electrics will be under the tail section. I have no problem picking it out, that was my original plan.
I digress, there IS a seat pan, there kind of has to be in order to have and mount a seat. I should have said I'm not using a traditional seat pan that attaches in the traditional way. All of the mounting and positioning have been worked out, a crude mock up has been made and a more reformed model that a mold will be taken from is in the works as we speak. The mold will be used to make a carbon fiber seat pan and mounting system. I'm keeping it close to the vest because if it works it'll be pretty cool, but also functional, if it doesn't work, back to the drawing board and a more traditional seat pan. Everything that you've said has been taken into account including first and foremost safety! No matter how cool it looks, I will not use it if it's not safe. In the end I will be riding this bike and it has to be safe. The seat pan that I plan will be solidly mounted to the frame both front and back. The main purpose of the tail section is to hide the mounting plate (steel) that will be welded to the frame and also to hide battery. All I can say is stay tuned, once I get it further along I would be happy to have you all examine and tear it apart if it's not safe. I value the input on this site, for the most part, there is a lot of knowledge and a lot of people with WAY more skill than me.
Mounting of the tail section and the "seat pan" have all been figured out, now it's just a matter of doing it and doing it safely...but bad assilly
Foam needs to be removed because my battery and electrics will be under the tail section. I have no problem picking it out, that was my original plan.
Re: I'm building a tail section
Well I'll be staying tuned to check it out then! FWIW, and since you are not laying up in a mold, I make a plan for everything I want to accomplish at a single effort when I start laying up glass. I cut up all the pieces of cloth quite carefully and trial fit them ( I mostly use cloth as opposed to mat), and then lay them all out in the order I will apply them. If the project is at all tricky I will spend a fair bit of time trying to imagine where the difficult areas are and how I will get done what I want. Epoxy is expensive and exotherms in a cup, so I want to have everything carefully thought out to avoid waste and re-do's. I know we are building street use motorcycle parts here, but I still make an effort to have a reasonably high glass to resin ratio for light weight and strength. I don't use carbon for this reason - without a lot more trouble, the carbon parts are very hard to make substantially lighter than the glass and for me it is not worth the expense. Plan your layups carefully, and avoid more resin than you need and you can make very light very strong parts for reasonable expense.
Well I'll be staying tuned to check it out then! FWIW, and since you are not laying up in a mold, I make a plan for everything I want to accomplish at a single effort when I start laying up glass. I cut up all the pieces of cloth quite carefully and trial fit them ( I mostly use cloth as opposed to mat), and then lay them all out in the order I will apply them. If the project is at all tricky I will spend a fair bit of time trying to imagine where the difficult areas are and how I will get done what I want. Epoxy is expensive and exotherms in a cup, so I want to have everything carefully thought out to avoid waste and re-do's. I know we are building street use motorcycle parts here, but I still make an effort to have a reasonably high glass to resin ratio for light weight and strength. I don't use carbon for this reason - without a lot more trouble, the carbon parts are very hard to make substantially lighter than the glass and for me it is not worth the expense. Plan your layups carefully, and avoid more resin than you need and you can make very light very strong parts for reasonable expense.
Re: I'm building a tail section
Yes. Same exact method, just exactly opposite. Essentially the way I build a mold off a plug minus the layer of gelcoat in between.billyp said:Bikes not going to have a seat pan
I was just stating the no mold part because J-rod is laying INSIDE a mold, I'm not using one, so I'll be laying around the OUTSIDE of the foam and I just wanted to see if his process of lay up would work the same. Acetone doesn't melt floral foam so I'll be chipping it out...no biggie. I'll double check with the epoxy and foam interaction but I'm pretty sure it won't melt it
billyp
Been Around the Block
Re: I'm building a tail section
Thank you for the advice jpmobius, I will definitely take it. I was going to cut some patterns out of some light paper or newsprint to see how it lays down to see were I may have problems and then cut glass accordingly. I'm thinking the only real problem area is going to be the vent, I'll probably for sure be making patterns of that
J-Rod, thanks man. Do you think if I draped the 3 oz cloth over the top perpendicular in layers like you said, up one side, across the top, down the other side that I could get the cloth to lay down in the vent area? Or would it have a better chance of laying down if I run the sides long ways, basically around, like you do? Or should I just plan on laying that area completely separate?
Thank you for the advice jpmobius, I will definitely take it. I was going to cut some patterns out of some light paper or newsprint to see how it lays down to see were I may have problems and then cut glass accordingly. I'm thinking the only real problem area is going to be the vent, I'll probably for sure be making patterns of that
J-Rod, thanks man. Do you think if I draped the 3 oz cloth over the top perpendicular in layers like you said, up one side, across the top, down the other side that I could get the cloth to lay down in the vent area? Or would it have a better chance of laying down if I run the sides long ways, basically around, like you do? Or should I just plan on laying that area completely separate?
Re: I'm building a tail section
I would go over those areas first with a fine mesh. Then lay it the way I posted. It'll give you multiple pieces through your recessed area. It's tough to get one piece in an area like that. The material wants to pop up around the edges.
I would go over those areas first with a fine mesh. Then lay it the way I posted. It'll give you multiple pieces through your recessed area. It's tough to get one piece in an area like that. The material wants to pop up around the edges.
Re: I'm building a tail section
I'll not get into semantics and insulting people's work. But, I know quite well what I am doing, and when, and why to use various mats/weaves.
Come to think of it, to the OP, you'll get your strongest part with the best surface if you go a couple layers of chopped strand, then a finish layer of your cloth. CSM is equally strong in every direction, while cloth is not.
I'll not get into semantics and insulting people's work. But, I know quite well what I am doing, and when, and why to use various mats/weaves.
Come to think of it, to the OP, you'll get your strongest part with the best surface if you go a couple layers of chopped strand, then a finish layer of your cloth. CSM is equally strong in every direction, while cloth is not.
