Hi everyone,
My last few posts have been about soft tops for the 40 and I thought I'd continue the tradition. I had a bit of an issue with the old vinyl top that came with my BJ40. I was driving in a windstorm and the top ripped. I took it in to get repaired and was told no can do because the top was so old and the vinyl had perished.
So there I was without a top on my DD at the tail end of winter - we have had some serious rain recently too which has kind of cramped my style.
I hadn't seen that ocdbeetle was manufacturing tops for sale, but I sent him a PM asking for some tech tips which he kindly replied to and gave me a start. I was going to post patterns and such, but seeing as there are quite a few Mudders who are making and retailing this sort of thing, out of respect I'll refrain and stick to a few more general issues I found during my bikini top build, which is a dress rehearsal for my OEM soft top build.
Being a neophyte stitch biatch, I had to first teach myself to sew and source a thread injecting assembly which could handle the materials. I settled on a 1940s vintage Singer (cost A$70 off ebay) which when used with the proper size needles, allowed me to sew 8 layers of perished soft top vinyl. I was impressed. I was using old Aussie milspec rot-proof thread - the stuff they used to use for canvas web gear and packs - which I scored for A$5 for a couple of thousand metres.
The bikini top was a prototype that I would use to make a pattern for the later canvas model, so the materials used are um... unconventional and will be rather short lived.
Materials:
A cheap poly tarp from Supercheap Auto
Some black shadecloth I had lying around the shed
Some nylon rope
A couple of ALICE pack shoulder straps
The rear tiedown straps salvaged from my old soft top.
Some square dowel
Some cheap brown marine vinyl
Firstly I made the basic top out of the poly tarp material. Took maybe an hour to cut and sew.
I test fitted it and took it for a test flight. The windshield frame interface was solid, but no matter how tight the rear adjustment straps were, it flapped against the roll bar. The top also blew up like a parachute, exacerbating the flapping problems and the noise was like I was driving inside a plastic bag in a windstorm.
I pondered and pondered, then hit upon the idea of lining the underside of the top with shadecloth. This would disrupt the airflow and maybe stop some of the flapping. I sewed it and it worked, although the back of the top still flapped against the top of the roll bar - very annoying.
Brainwave number two was to sew a length of square dowel tinto the back of the top which would hold it against the roll bar. I measured, I sewed, I re-fitted the top and took it for a run on the freeway. The flapping was much reduced, and had been replaced by an annoying banging as a small gap between the roll bar and the sewn-in dowel caused it to bash against the roll bar periodically while I was driving.
I ended up skinning the bikini top with marine vinyl which provided enough padding to fill the gap and stop the flapping/banging.
Now I have a drumskin-tight 3-layer bikini top that makes absolutely no noise while I'm driving at 100-110 km/h. I'm very happy with the result and nearly ready to move onto the canvas final product.
This will be a double layer top, having an olive drab canvas shell and an olive drab nomex or nylon rachel mesh (military vest mesh) lining to stop the top from flapping.
I'll continue using the dowel in the back of the top, but I'll glue a sheath of vinyl over the dowel before sewing it into the canvas to give some padding.
I'm all out of spare nylon webbing ALICE pack straps, so I'll use some surplus US 1" olive drab military cotton webbing for the rear straps. I'm using this stuff on the OEM soft top I'm designing as well - it'll look more utilitarian and vintage than commercial nylon or polyester webbing. I tracked down some metal buckles (2 types - modern black steel US military, and surplus WWII black oxidised brass) so it should have the complete vintage look. Wait until you see what I'm using instead of side and rear zippers for the full soft top LOL.
So hopefully, any of you folks who are having troubles with the bikini tops flapping can take some of these ideas and use them.
I know this thread is useless without pics, but I'm between cameras at the moment. I'll hopefully be able to take some pics later this week. The design and mods will make more sense.
I'm also halfway through building a windjammer to use with the bikini top made from the same prototype materials as the top. It should be ready to fit in a couple of days. It has been a design challenge, especially when it comes to coverage for the gap between the door and the attachment point on the roll bar, but I have solved the problem and can't wait to build it.
Cheers
My last few posts have been about soft tops for the 40 and I thought I'd continue the tradition. I had a bit of an issue with the old vinyl top that came with my BJ40. I was driving in a windstorm and the top ripped. I took it in to get repaired and was told no can do because the top was so old and the vinyl had perished.
So there I was without a top on my DD at the tail end of winter - we have had some serious rain recently too which has kind of cramped my style.
I hadn't seen that ocdbeetle was manufacturing tops for sale, but I sent him a PM asking for some tech tips which he kindly replied to and gave me a start. I was going to post patterns and such, but seeing as there are quite a few Mudders who are making and retailing this sort of thing, out of respect I'll refrain and stick to a few more general issues I found during my bikini top build, which is a dress rehearsal for my OEM soft top build.
Being a neophyte stitch biatch, I had to first teach myself to sew and source a thread injecting assembly which could handle the materials. I settled on a 1940s vintage Singer (cost A$70 off ebay) which when used with the proper size needles, allowed me to sew 8 layers of perished soft top vinyl. I was impressed. I was using old Aussie milspec rot-proof thread - the stuff they used to use for canvas web gear and packs - which I scored for A$5 for a couple of thousand metres.
The bikini top was a prototype that I would use to make a pattern for the later canvas model, so the materials used are um... unconventional and will be rather short lived.
Materials:
A cheap poly tarp from Supercheap Auto
Some black shadecloth I had lying around the shed
Some nylon rope
A couple of ALICE pack shoulder straps
The rear tiedown straps salvaged from my old soft top.
Some square dowel
Some cheap brown marine vinyl
Firstly I made the basic top out of the poly tarp material. Took maybe an hour to cut and sew.
I test fitted it and took it for a test flight. The windshield frame interface was solid, but no matter how tight the rear adjustment straps were, it flapped against the roll bar. The top also blew up like a parachute, exacerbating the flapping problems and the noise was like I was driving inside a plastic bag in a windstorm.
I pondered and pondered, then hit upon the idea of lining the underside of the top with shadecloth. This would disrupt the airflow and maybe stop some of the flapping. I sewed it and it worked, although the back of the top still flapped against the top of the roll bar - very annoying.
Brainwave number two was to sew a length of square dowel tinto the back of the top which would hold it against the roll bar. I measured, I sewed, I re-fitted the top and took it for a run on the freeway. The flapping was much reduced, and had been replaced by an annoying banging as a small gap between the roll bar and the sewn-in dowel caused it to bash against the roll bar periodically while I was driving.
I ended up skinning the bikini top with marine vinyl which provided enough padding to fill the gap and stop the flapping/banging.
Now I have a drumskin-tight 3-layer bikini top that makes absolutely no noise while I'm driving at 100-110 km/h. I'm very happy with the result and nearly ready to move onto the canvas final product.
This will be a double layer top, having an olive drab canvas shell and an olive drab nomex or nylon rachel mesh (military vest mesh) lining to stop the top from flapping.
I'll continue using the dowel in the back of the top, but I'll glue a sheath of vinyl over the dowel before sewing it into the canvas to give some padding.
I'm all out of spare nylon webbing ALICE pack straps, so I'll use some surplus US 1" olive drab military cotton webbing for the rear straps. I'm using this stuff on the OEM soft top I'm designing as well - it'll look more utilitarian and vintage than commercial nylon or polyester webbing. I tracked down some metal buckles (2 types - modern black steel US military, and surplus WWII black oxidised brass) so it should have the complete vintage look. Wait until you see what I'm using instead of side and rear zippers for the full soft top LOL.
So hopefully, any of you folks who are having troubles with the bikini tops flapping can take some of these ideas and use them.
I know this thread is useless without pics, but I'm between cameras at the moment. I'll hopefully be able to take some pics later this week. The design and mods will make more sense.
I'm also halfway through building a windjammer to use with the bikini top made from the same prototype materials as the top. It should be ready to fit in a couple of days. It has been a design challenge, especially when it comes to coverage for the gap between the door and the attachment point on the roll bar, but I have solved the problem and can't wait to build it.
Cheers
