Trimming wet twill

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Trimming wet twill

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chriscnf	c chriscnf posted 3 Years Ago HOT Topic Details
c Group: Forum Members Posts: 34, Visits: 2.7K	Hi guys...I'm doing hand layup with a closed three part mold and compressing with a bladder. Trimming wet twill is difficult but it has advantages over waiting for the epoxy to tack up a bit (I use peel ply and breather cloth to remove excess epoxy). Is there a trick here I'm missing to make the job easier? I use small curved bladed scissors and sharpness is key but so is scissor quality, I opened two pair for the last layup and one trimmed pretty well while the other went in the bin. I don't mind spending money if someone can suggest a high quality curved blade set. All the best...Chris
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jeffrey bres	j jeffrey bres posted 3 Years Ago HOT Post Details
j Group: Forum Members Posts: 42, Visits: 469	+x chriscnf - 3/1/2021 6:24:03 PM Hi guys...I'm doing hand layup with a closed three part mold and compressing with a bladder. Trimming wet twill is difficult but it has advantages over waiting for the epoxy to tack up a bit (I use peel ply and breather cloth to remove excess epoxy). Is there a trick here I'm missing to make the job easier? I use small curved bladed scissors and sharpness is key but so is scissor quality, I opened two pair for the last layup and one trimmed pretty well while the other went in the bin. I don't mind spending money if someone can suggest a high quality curved blade set. All the best...Chris Im just in the learning curve here. But what ive been told.(rc boats..) with 2 part closed moulds. They use peelply on the edge they want to join if the mould is completely closed and they cant reach in. When its firm but still sticky enough to stick to each other with easy they trim it by running a new stanleyknife blade or razorblade along the edge of the mould. Then join it with a little bit of fresh epoxy with cottonflakes on the edge. Ive just made my first wet in wet layd boat. Did what they sayd. and its a nice fine seem thats super easy to trim after demoulding. Just ran a razor blade along the seem when it was demoulded. Offcourse. Cut the fiber in the direction of the mould to not prerelease the part. And i layd the knifes edge flat against the mould at all times.. Verry interested in what our pros and diehards have to comment on this topic.
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chriscnf	c chriscnf posted 3 Years Ago HOT Post Details
c Group: Forum Members Posts: 34, Visits: 2.7K	+x jeffrey bres - 3/4/2021 12:23:06 AM +x chriscnf - 3/1/2021 6:24:03 PM Hi guys...I'm doing hand layup with a closed three part mold and compressing with a bladder. Trimming wet twill is difficult but it has advantages over waiting for the epoxy to tack up a bit (I use peel ply and breather cloth to remove excess epoxy). Is there a trick here I'm missing to make the job easier? I use small curved bladed scissors and sharpness is key but so is scissor quality, I opened two pair for the last layup and one trimmed pretty well while the other went in the bin. I don't mind spending money if someone can suggest a high quality curved blade set. All the best...Chris Im just in the learning curve here. But what ive been told.(rc boats..) with 2 part closed moulds. They use peelply on the edge they want to join if the mould is completely closed and they cant reach in. When its firm but still sticky enough to stick to each other with easy they trim it by running a new stanleyknife blade or razorblade along the edge of the mould. Then join it with a little bit of fresh epoxy with cottonflakes on the edge. Ive just made my first wet in wet layd boat. Did what they sayd. and its a nice fine seem thats super easy to trim after demoulding. Just ran a razor blade along the seem when it was demoulded. Offcourse. Cut the fiber in the direction of the mould to not prerelease the part. And i layd the knifes edge flat against the mould at all times.. Verry interested in what our pros and diehards have to comment on this topic. So the peel ply helps with trimming and is then removed? Could you give me a link to the site you use...cheers for your help...Chris
	Reply Like 2
jeffrey bres	j jeffrey bres posted 3 Years Ago HOT Post Details
j Group: Forum Members Posts: 42, Visits: 469	+x chriscnf - 3/4/2021 5:04:55 AM +x jeffrey bres - 3/4/2021 12:23:06 AM +x chriscnf - 3/1/2021 6:24:03 PM Hi guys...I'm doing hand layup with a closed three part mold and compressing with a bladder. Trimming wet twill is difficult but it has advantages over waiting for the epoxy to tack up a bit (I use peel ply and breather cloth to remove excess epoxy). Is there a trick here I'm missing to make the job easier? I use small curved bladed scissors and sharpness is key but so is scissor quality, I opened two pair for the last layup and one trimmed pretty well while the other went in the bin. I don't mind spending money if someone can suggest a high quality curved blade set. All the best...Chris Im just in the learning curve here. But what ive been told.(rc boats..) with 2 part closed moulds. They use peelply on the edge they want to join if the mould is completely closed and they cant reach in. When its firm but still sticky enough to stick to each other with easy they trim it by running a new stanleyknife blade or razorblade along the edge of the mould. Then join it with a little bit of fresh epoxy with cottonflakes on the edge. Ive just made my first wet in wet layd boat. Did what they sayd. and its a nice fine seem thats super easy to trim after demoulding. Just ran a razor blade along the seem when it was demoulded. Offcourse. Cut the fiber in the direction of the mould to not prerelease the part. And i layd the knifes edge flat against the mould at all times.. Verry interested in what our pros and diehards have to comment on this topic. So the peel ply helps with trimming and is then removed? Could you give me a link to the site you use...cheers for your help...Chris No the peel doesnt help. What they told me.. put peel on the edge. When wet. Then wait till its firm enough to not delaminate when you cut it... and put some new mixed epoxy on the edge with a little bit of cotton flocks. So i did what they sayd.(just a little.. you dont want to much resin on the edge you join..) and after you joined them. And its cured. Remove the bladder. Pull the peelply off and lay a glasstape or carbon tape over the joined edge. Im just a noob. So. Onky can tell what they told me. i didnt use peelply in this foto. But this is my join on the inside when i closed the mould.(i dont use a bladder) but that seem needs to be tight. So it joins up then closed. I dont know if youre able to get in when the mould id closed.. but would be best if you can to lay a tape over it before you insert the bladder. Then its 1 piece. Biaxial carbon tape or glass or whatever. i can luckely reach in easy to join the tape but cant vacuum.. or use a bladder at home. Unfortunantly.
	Reply Like 2
Hanaldo	Hanaldo posted 3 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Yeh unfortunately what Jeffrey is saying won't really work for you, because you are wanting to get your bladder in place and squeezing the excess resin out while it is still wet, you can't wait for the resin to firm up as he is saying. Unfortunately there is no real trick here that will help, wet carbon just isn't going to trim easily or neatly. As you have discovered, sharp shears make it a bit easier, but even the best shears will make a bit of a mess of it. You certainly can't trim it as neatly as you could a pre-preg or a b-staged resin. You kind of have to choose what your priority is, do you want to get the excess resin out or do you want to have a neat seam. If the neat seam is more important, you could do similar to what Jeffrey is suggesting and let the resin firm up a bit, trim the edges with a razor, then before the epoxy cures too far you bolt your moulds together with an overlap and apply pressure via the bladder. If you get the timing right, the resin should still be liquid enough to squeeze out a bit of excess, but obviously not as much as if you had applied pressure straight away. You may also find this causes issues with trapping voids, as air won't escape as easily through the thicker resin. Alternatively, a 'wet-preg' may be a more suitable process for you, as it allows you to trim the material much more accurately than you could when it is dry, and then you can handle it almost like a proper pre-preg. This way you may be able to trim the material accurately enough to just have to position it into your mould, and not have any excess to trim off., and you can still get the consolidation on while the resin is quite wet.
	Reply Like 3
chriscnf	c chriscnf posted 3 Years Ago HOT Post Details
c Group: Forum Members Posts: 34, Visits: 2.7K	+x Hanaldo - 3/5/2021 2:38:53 AM Yeh unfortunately what Jeffrey is saying won't really work for you, because you are wanting to get your bladder in place and squeezing the excess resin out while it is still wet, you can't wait for the resin to firm up as he is saying. Unfortunately there is no real trick here that will help, wet carbon just isn't going to trim easily or neatly. As you have discovered, sharp shears make it a bit easier, but even the best shears will make a bit of a mess of it. You certainly can't trim it as neatly as you could a pre-preg or a b-staged resin. You kind of have to choose what your priority is, do you want to get the excess resin out or do you want to have a neat seam. If the neat seam is more important, you could do similar to what Jeffrey is suggesting and let the resin firm up a bit, trim the edges with a razor, then before the epoxy cures too far you bolt your moulds together with an overlap and apply pressure via the bladder. If you get the timing right, the resin should still be liquid enough to squeeze out a bit of excess, but obviously not as much as if you had applied pressure straight away. You may also find this causes issues with trapping voids, as air won't escape as easily through the thicker resin. Alternatively, a 'wet-preg' may be a more suitable process for you, as it allows you to trim the material much more accurately than you could when it is dry, and then you can handle it almost like a proper pre-preg. This way you may be able to trim the material accurately enough to just have to position it into your mould, and not have any excess to trim off., and you can still get the consolidation on while the resin is quite wet. That's pretty much the conclusion I had come to Hanaldo but lots of edges in a long three part mold. I haven't calculated my fiber/epoxy contents but I get the that pretty low wetting out the cloths in their stack between plastic sheets and working out excess resin so there isn't a desperate need to extract resin. The ultimate would be prepreg but I need a smarter mold and a supply to make that work. Appreciate yours and Jeffrey's input...now I know that it is what it is.
	Reply Like 3
chriscnf	c chriscnf posted 3 Years Ago HOT Post Details
c Group: Forum Members Posts: 34, Visits: 2.7K	+x jeffrey bres - 3/4/2021 12:06:56 PM +x chriscnf - 3/4/2021 5:04:55 AM +x jeffrey bres - 3/4/2021 12:23:06 AM +x chriscnf - 3/1/2021 6:24:03 PM Hi guys...I'm doing hand layup with a closed three part mold and compressing with a bladder. Trimming wet twill is difficult but it has advantages over waiting for the epoxy to tack up a bit (I use peel ply and breather cloth to remove excess epoxy). Is there a trick here I'm missing to make the job easier? I use small curved bladed scissors and sharpness is key but so is scissor quality, I opened two pair for the last layup and one trimmed pretty well while the other went in the bin. I don't mind spending money if someone can suggest a high quality curved blade set. All the best...Chris Im just in the learning curve here. But what ive been told.(rc boats..) with 2 part closed moulds. They use peelply on the edge they want to join if the mould is completely closed and they cant reach in. When its firm but still sticky enough to stick to each other with easy they trim it by running a new stanleyknife blade or razorblade along the edge of the mould. Then join it with a little bit of fresh epoxy with cottonflakes on the edge. Ive just made my first wet in wet layd boat. Did what they sayd. and its a nice fine seem thats super easy to trim after demoulding. Just ran a razor blade along the seem when it was demoulded. Offcourse. Cut the fiber in the direction of the mould to not prerelease the part. And i layd the knifes edge flat against the mould at all times.. Verry interested in what our pros and diehards have to comment on this topic. So the peel ply helps with trimming and is then removed? Could you give me a link to the site you use...cheers for your help...Chris No the peel doesnt help. What they told me.. put peel on the edge. When wet. Then wait till its firm enough to not delaminate when you cut it... and put some new mixed epoxy on the edge with a little bit of cotton flocks. So i did what they sayd.(just a little.. you dont want to much resin on the edge you join..) and after you joined them. And its cured. Remove the bladder. Pull the peelply off and lay a glasstape or carbon tape over the joined edge. Im just a noob. So. Onky can tell what they told me. i didnt use peelply in this foto. But this is my join on the inside when i closed the mould.(i dont use a bladder) but that seem needs to be tight. So it joins up then closed. I dont know if youre able to get in when the mould id closed.. but would be best if you can to lay a tape over it before you insert the bladder. Then its 1 piece. Biaxial carbon tape or glass or whatever. i can luckely reach in easy to join the tape but cant vacuum.. or use a bladder at home. Unfortunantly. I had a go with a sharp blade and it works well, and right up until its nearly cured. A useful technique indeed...cheers.
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