That's what she said...
Congratulations! Looks awesome man. Glad you got it worked out-
:clapping: Hahahaha nice one!
Off-road teardrop scratch-build
- Thread starter rob cote
- Start date
:clapping: Hahahaha nice one!
Thank you for the kind words. Unfortunately, the curve didn't stick. I un-clamped the panel and it sprung back about halfway. There's a lot of variables to play with; make the panel hotter or wetter, keep it hot/wet for longer, let it "cure" for longer. I'm not really sure what to try. Might try getting the water hotter I suppose, and using that to get the panel hotter. Open to suggestions, and I need to try to do some research on my own as well.
ottsville
Observer
Mount it on the trailer and rebend it, then make the permanent attachments. It's going spring off of any mold unless your kerfs are almost through the board. I know Dan went through this is in his build, so he can give you better advice.
I forget what your exterior finish is going to be, but if I was laminating something to the outside I would bother bending major curves - I would do it in strips, fill the gaps with filler of some sort and sand it to shape.
Your build is beautiful though and I am enjoying following it.
I forget what your exterior finish is going to be, but if I was laminating something to the outside I would bother bending major curves - I would do it in strips, fill the gaps with filler of some sort and sand it to shape.
Your build is beautiful though and I am enjoying following it.
indiedog
Adventurer
Prob a little late to assist unless you've got the bits you cut off your formwork pieces, but the formwork I've seen from the composite panel guys and ply guys is usually on the outside of the bend, not the inside. That way you don't need clamps to keep it in place and you have the inside free of formwork to then place permanent ribs etc which hold the finished product in place. Also running some fibreglass over the kerfed section will assist a lot. On the bendy end make a lip on the formwork so the end of the bendy piece is held in place then either clamp or use another lip to stop the straight end from moving. May not help now but for future reference. 
Keep up the good work mate.
Keep up the good work mate.
Teardropper
Well-known member
Great build.
How'd you cut out your cabinet doors?
How'd you cut out your cabinet doors?
Prob a little late to assist unless you've got the bits you cut off your formwork pieces, but the formwork I've seen from the composite panel guys and ply guys is usually on the outside of the bend, not the inside. That way you don't need clamps to keep it in place and you have the inside free of formwork to then place permanent ribs etc which hold the finished product in place. Also running some fibreglass over the kerfed section will assist a lot. On the bendy end make a lip on the formwork so the end of the bendy piece is held in place then either clamp or use another lip to stop the straight end from moving. May not help now but for future reference.
Keep up the good work mate.
That actually might still have some nuggets of helpfulness in it. Thanks for that. I tried processing it again this time using hotter water (near boiling). I let it dry out for a day and a half, and it wanted to spring back to nearly-flat. I clamped it back to the form and I'm just leaving it there until I need it. Maybe it'll take on a little more bend on its own, maybe not. I have been thinking about what to do on the inside. I've thought about filling in all the grooves with epoxy, just to get some strength back in the panel, but I figure it'll probably tend to ooze out. But laying some glass sheets down in there might be a great solution for keeping everything in place.
Very carefully!
I setup a straightedge and plunge-cut with a circular saw for the straight cuts. Then I free-handed the corners with a jig saw and a fine tooth blade. The corners are the scariest part.
Titanpat57
Expedition Leader
Use to stuff called Whacky Wood...used in making curved cabinets. Try a local cabinet building shop/supplier.
Rob, I would first see if you can bend it back to the form and clamp it without it breaking or cracking. If it can do that, I would apply something like 3M 5200 fast cure adhesive along the ribs and clamp it down again, adding whatever additional fasteners you were going to originally use.
If it doesn't want to lay down to the curve without cracking, I would go through the hot water routine again with the clamps and leave it longer. The only adhesive I am aware of that you can use in a wet application that will hold like you want it to would be the Loctite Marine Epoxy. Remember that both of the adhesives I've written about here are permanent. As in, they won't come off.
I remember at one time I was contemplating doing the curve using wood strips like you do in wood strip canoe construction. I never got around to trying it, but that is certainly another option. It would be relatively easy for a guy with your skills to set up a jig to plane the strip edges to a chamfer that would be relatively snug. Then glue the edges and on the ribs with good old Elmers (or whatever will plane and sand easily). Use your pin nailer to pin the strips to the ribs, setting the nailer so the pins are under the surface if you want to leave them in after the glue sets, or just proud if you want to remove them. Fill and sand smooth when you are satisfied the adhesives have fully set. If you want to assure water integrity, you will need a weatherproof covering, but as I recall it's getting an aluminum cover, right?
Keep going, you are doing great.
If it doesn't want to lay down to the curve without cracking, I would go through the hot water routine again with the clamps and leave it longer. The only adhesive I am aware of that you can use in a wet application that will hold like you want it to would be the Loctite Marine Epoxy. Remember that both of the adhesives I've written about here are permanent. As in, they won't come off.
I remember at one time I was contemplating doing the curve using wood strips like you do in wood strip canoe construction. I never got around to trying it, but that is certainly another option. It would be relatively easy for a guy with your skills to set up a jig to plane the strip edges to a chamfer that would be relatively snug. Then glue the edges and on the ribs with good old Elmers (or whatever will plane and sand easily). Use your pin nailer to pin the strips to the ribs, setting the nailer so the pins are under the surface if you want to leave them in after the glue sets, or just proud if you want to remove them. Fill and sand smooth when you are satisfied the adhesives have fully set. If you want to assure water integrity, you will need a weatherproof covering, but as I recall it's getting an aluminum cover, right?
Keep going, you are doing great.
Really appreciate all the help and insight you guys. You've given me a lot to consider. My thoughts at present are as follows.
The kerf-cut panel has enough flexibility to be bent dry by hand onto the jig I made (which is the same curve as the end product. It doesn't want to crack or splinter. So I think this is an encouraging fact. It's currently, and will remain, clamped to the jig, until we're ready to assemble it to the trailer. We need walls up before that to support it, so that it's not just dangling out in free space. I'm thinking that we can just force it into submission with fasteners (and likely glue as well at final assembly). I don't think this will pose a significant problem or be overly challenging to execute. The main issue that I have with doing it this way is that it will put the fasteners in tension. IDEALLY, the panel would have the correct shape, and the fasteners would be there just to hold it in place, rather than holding it in form AND in place. Does that make sense? Will it be a problem? I don't think that it will, but I'm just thinking, it's not the best-case scenario. Then again, we don't live in an ideal world, so it's probably nothing.
The kerf-cut panel has enough flexibility to be bent dry by hand onto the jig I made (which is the same curve as the end product. It doesn't want to crack or splinter. So I think this is an encouraging fact. It's currently, and will remain, clamped to the jig, until we're ready to assemble it to the trailer. We need walls up before that to support it, so that it's not just dangling out in free space. I'm thinking that we can just force it into submission with fasteners (and likely glue as well at final assembly). I don't think this will pose a significant problem or be overly challenging to execute. The main issue that I have with doing it this way is that it will put the fasteners in tension. IDEALLY, the panel would have the correct shape, and the fasteners would be there just to hold it in place, rather than holding it in form AND in place. Does that make sense? Will it be a problem? I don't think that it will, but I'm just thinking, it's not the best-case scenario. Then again, we don't live in an ideal world, so it's probably nothing.
Factoid
Three criminal heroes
Just read the entire thread, great job executing your build!
A suggestion to help you address your curved sheathing challenge. Use an “outside” or concave bending jig to hold your bent plywood to the proper curve. Use a small Brad nailer to hold it in place. Once it dries, West System epoxy can be used to lock the curve. It has a thickener you can add to thicken it up just enough to trowel it on and force it into the kerf of the saw cuts. Clamp a piece of plywood covered in wax paper to the ends to it doesn’t run out. When properly thickened, it won’t pool up. Once cured, your curved plywood sheathing will be stronger than ever and will be locked in the proper form. Pry the forms off and grind the Brad stubs flush.
Best of luck and thank you for sharing the details of your build. Much appreciated!
A suggestion to help you address your curved sheathing challenge. Use an “outside” or concave bending jig to hold your bent plywood to the proper curve. Use a small Brad nailer to hold it in place. Once it dries, West System epoxy can be used to lock the curve. It has a thickener you can add to thicken it up just enough to trowel it on and force it into the kerf of the saw cuts. Clamp a piece of plywood covered in wax paper to the ends to it doesn’t run out. When properly thickened, it won’t pool up. Once cured, your curved plywood sheathing will be stronger than ever and will be locked in the proper form. Pry the forms off and grind the Brad stubs flush.
Best of luck and thank you for sharing the details of your build. Much appreciated!
indiedog
Adventurer
Rob, there's no way that just wetting it down and letting it dry in the shape you want will get that piece to stay that way without some external forces holding it there. If it can bend while dry to the shape you want then there's really no need to wet it down. You will have to add some gussets internally which will hold it in place. Adding glass inside and out will also help but as with all structures the deeper the overall structure is the stronger it will be.
I gather this is part of the roof and curve going down to the front wall? Any reason you can't just glue it in place? And yes, continuous glue will be a lot better than just screws at the end, another reason for fixing it dry. Can you add a few internal gussets that can stay in place when you fix it to the trailer? Sorry if that's too may suggestions. Probably if you showed where it will be fixed and what there is to hold it in place we may have more focused suggestions.
I gather this is part of the roof and curve going down to the front wall? Any reason you can't just glue it in place? And yes, continuous glue will be a lot better than just screws at the end, another reason for fixing it dry. Can you add a few internal gussets that can stay in place when you fix it to the trailer? Sorry if that's too may suggestions.
Probably if you showed where it will be fixed and what there is to hold it in place we may have more focused suggestions. My mistake you guys. I thought I had explained why I'm trying to bend this piece, and where it's going. But apparently I didn't. Anyway.
In this picture, the front wall is shown in place:
We've since cut ~8" off the top of it, which exposes the full extent of the curve. We realized trying to scarf two pieces together mid-curve was just trying way too hard and totally unnecessary.
So without the front wall in place, you can see where the inner walls are, and most notably, the curve on top:
So the bent panel will meet the front wall panel (shown above) and it will curve from vertical to horizontal to form the roof.
Does that make sense? It's hard to describe something 3D in words without showing, which I'm finding I struggle with quite a lot when trying to explain my ideas to the wife. Anyway, thank you all so much for the kind words and input. It's immensely helpful. It's been a little overwhelming lately just feeling like there's a million small tasks left to do. Just gotta keep chipping away at it one thing at a time.
So last night we got a gasket/stop feature installed for the fridge drawer and the water heater door. I completely forgot to grab pictures. I will tonight. I'm very pleased with how it came out, the openings look much more "finished" with the seal in place.
In this picture, the front wall is shown in place:
We've since cut ~8" off the top of it, which exposes the full extent of the curve. We realized trying to scarf two pieces together mid-curve was just trying way too hard and totally unnecessary.
So without the front wall in place, you can see where the inner walls are, and most notably, the curve on top:
So the bent panel will meet the front wall panel (shown above) and it will curve from vertical to horizontal to form the roof.
Does that make sense? It's hard to describe something 3D in words without showing, which I'm finding I struggle with quite a lot when trying to explain my ideas to the wife. Anyway, thank you all so much for the kind words and input. It's immensely helpful. It's been a little overwhelming lately just feeling like there's a million small tasks left to do. Just gotta keep chipping away at it one thing at a time.
So last night we got a gasket/stop feature installed for the fridge drawer and the water heater door. I completely forgot to grab pictures. I will tonight. I'm very pleased with how it came out, the openings look much more "finished" with the seal in place.
ottsville
Observer
You won't get the wall piece to bend on the form and hold the final shape without doing something more to it - glass, glue, screwed blocks, etc.
Are you trying to install the end wall in place on just the two curved vertical wall dividers? I think you need to do it with either the side walls installed or, at least, curved ribs installed to hold the correct shape of the curve.
How are you planning on attaching the wall - screws or glue? Is your curved wall coming up and attaching to the plywood wall running right to left? Have you considered adding a rib at the top of that right to left wall to give you a more secure attachment point?
Are you trying to install the end wall in place on just the two curved vertical wall dividers? I think you need to do it with either the side walls installed or, at least, curved ribs installed to hold the correct shape of the curve.
How are you planning on attaching the wall - screws or glue? Is your curved wall coming up and attaching to the plywood wall running right to left? Have you considered adding a rib at the top of that right to left wall to give you a more secure attachment point?