Discussion
I've come to the conclusion that the MK1 splitter design needs a re-think. I much prefer the look with it on, and I can pretend I feel the difference at legal road speeds, however it scrapes on sleeping policemen, I hit in when parking into a kerb, it's fibreglass which chips and cracks and soon looks rubbish.
From my perspective (which I'm entitled to) there are two problems, the amount it protrudes and the material which is too brittle. Mine disappeared last week, whilst driving in a spirited manner (fortunately on a deserted back road)it cracked and disappeared under the car.
I could fork out £120 for a new one, which might last another year or so, but I decided to have a go at making something my own. The idea is an aluminium (note that spelling American cousins) and marine ply sandwich, with the aluminium folded over the front edge to provide some protection. It should be strong enough and have enough flex to stop cracking if it does get a knock, and at the same time I will preserve the shape and make it protrude less.
This could all go horribly wrong of course, but I have the materials and it makes an interesting project. So, shape cut out for the plywood filling and the first aluminium sheet, cut, filed, degreased and bonded. Once that"s set I'll add another sheet of aluminium with excess to fold over and ultimately I'll rivet it as well as I don't trust adhesives...... Not looking forward to folding on a curve, it's fiddly without a stretcher/shrinker.
Plywood cut and holes marked
|https://thumbsnap.com/Qpzc2mtm[/url]
First layer of Ali and wood bonded
From my perspective (which I'm entitled to) there are two problems, the amount it protrudes and the material which is too brittle. Mine disappeared last week, whilst driving in a spirited manner (fortunately on a deserted back road)it cracked and disappeared under the car.
I could fork out £120 for a new one, which might last another year or so, but I decided to have a go at making something my own. The idea is an aluminium (note that spelling American cousins) and marine ply sandwich, with the aluminium folded over the front edge to provide some protection. It should be strong enough and have enough flex to stop cracking if it does get a knock, and at the same time I will preserve the shape and make it protrude less.
This could all go horribly wrong of course, but I have the materials and it makes an interesting project. So, shape cut out for the plywood filling and the first aluminium sheet, cut, filed, degreased and bonded. Once that"s set I'll add another sheet of aluminium with excess to fold over and ultimately I'll rivet it as well as I don't trust adhesives...... Not looking forward to folding on a curve, it's fiddly without a stretcher/shrinker.
Plywood cut and holes marked
|https://thumbsnap.com/Qpzc2mtm[/url]First layer of Ali and wood bonded
I'm with you. Made mine from 2 pieces of dibond bonded together (its aluminum skinned plastic cored composite stuff). Worked a treat. Read its quite popular for automotive bodywork fabrication add-ons. I protected the front edge with push on plastic channel...I have bounced off it lightly when parking on several occasions and its survived unscathed
Spent some more time this evening trying to make progress. I think the idea is almost right but what I've ended up with is probably too rigid (albeit no heavier than the fibreglass original) and it needs more work.
The plywood and aluminium had bonded well overnight(s), so I could use the curve to create a) a former from a heavy bit of scrap wood (when I've finished with it, does it become a latter??) and b) the other aluminium panel, with flanges
Then the former was clamped to the panel and the edges dressed over to form a neat curve. The problem, as you can see, is that the folded edge crinkles - this is where a shrinker is needed but I don't have one.The solution is to cut a narrow 'V' where the crinkles are - in this case I cut 3
The next bit was tricky. I had a piece of 6mm ali rod which I cold formed (aka bent
) along the edge of the former so it had the same curve as the edge of the splitter. I clamped it all the panels together and held the rod in place whilst I used a light hammer (not the rubber mallet in the picture to fold the curved edge over the rod so that I had a thicker leading edge .
The problem I hit, which I expected, is the work hardening of the aluminium, the only solution is annealing, and with a wooden core it probably won't work. The effect is there but the leading edge is going to need a lot of dressing, and then probably a gentle kiss with a weld grinding wheel on an angle grinder and a file to smooth it all off.
Next step is to rivet the flanges, dress, prime and paint. If it looks good enough I might try something colour wise, if not it'll be black.
The plywood and aluminium had bonded well overnight(s), so I could use the curve to create a) a former from a heavy bit of scrap wood (when I've finished with it, does it become a latter??) and b) the other aluminium panel, with flanges
Then the former was clamped to the panel and the edges dressed over to form a neat curve. The problem, as you can see, is that the folded edge crinkles - this is where a shrinker is needed but I don't have one.The solution is to cut a narrow 'V' where the crinkles are - in this case I cut 3
The next bit was tricky. I had a piece of 6mm ali rod which I cold formed (aka bent
) along the edge of the former so it had the same curve as the edge of the splitter. I clamped it all the panels together and held the rod in place whilst I used a light hammer (not the rubber mallet in the picture to fold the curved edge over the rod so that I had a thicker leading edge .The problem I hit, which I expected, is the work hardening of the aluminium, the only solution is annealing, and with a wooden core it probably won't work. The effect is there but the leading edge is going to need a lot of dressing, and then probably a gentle kiss with a weld grinding wheel on an angle grinder and a file to smooth it all off.
Next step is to rivet the flanges, dress, prime and paint. If it looks good enough I might try something colour wise, if not it'll be black.
Yes, that was one of my thoughts when I started. The wood is marine ply, so is treated. I was hoping the ali would provide a pretty good seal but the wood is exposed at the corners and back edge. I have some rubber u-section for the back edge (also to cushion against the bottom of the car), but I think it will be black sealant on the corners.
I originally planned to put sealant under the flanges, but folding the leading edge was a pig and it would have got everywhere. I can always run a bead around them after painting.
I originally planned to put sealant under the flanges, but folding the leading edge was a pig and it would have got everywhere. I can always run a bead around them after painting.
Konrod said:
The wood is marine ply, so is treated.
I think it will be black sealant on the corners.
Well done you & keep posting pictures. Product development before our eyes I think it will be black sealant on the corners.
Just some useless information;
Marine ply isn't usually treated. In some applications it can be pressure treated, at vast expense. As a simple definition, the veneers used are defect free, the adhesive is external grade and is moisture resistant. It can be cut anywhere without the prospect of exposing a "void"
As a sealant I would highly recommend CT1
Hi, I've been reading your thread with interest. I experimented over 7 years with various splitters and areo when I was racing. Some guys used just the marine ply (5 mm thick) painted matt black. This was deemed sacrificial and a lot cheaper to replace than carbon.
However I used aluminium. The optimum arrangement I found was 2mm thick aluminium sheet extending forward past the vehicles front apron no more than 21/2" and extending back under the front of the car to attach to the front sub frame. Any longer at the front would bend at over 100mph. To increase the 21/2" to 3" or slightly longer required additional support from additional areo above the splitter, see attached.
If I went off in the gravel, the aluminium would give but the fibreglass front of the vehicle would survive. Which just required another weekend of cutting and shaping aluminium (not fibre glassing).
I only offer this information as I feel you could utilise one of the materials you are experimenting with.
Other guys I knew at the time also built good splitters using plastic honeycomb sheeting used for advertising boards, again sacrificial in the event of an accident.
However I used aluminium. The optimum arrangement I found was 2mm thick aluminium sheet extending forward past the vehicles front apron no more than 21/2" and extending back under the front of the car to attach to the front sub frame. Any longer at the front would bend at over 100mph. To increase the 21/2" to 3" or slightly longer required additional support from additional areo above the splitter, see attached.
If I went off in the gravel, the aluminium would give but the fibreglass front of the vehicle would survive. Which just required another weekend of cutting and shaping aluminium (not fibre glassing).
I only offer this information as I feel you could utilise one of the materials you are experimenting with.
Other guys I knew at the time also built good splitters using plastic honeycomb sheeting used for advertising boards, again sacrificial in the event of an accident.
Life got on the way, and then the immobiliser packed up which necessitated a week away at the TVR surgeon. Having got it back I fitted it this weekend. It sits further back so be less open to damage.
In truth, I'm not happy with the finish, the curved front isn't smooth, but I know what I did wrong and will correct it next time I need to change it. I can knock one up now in a couple of evenings as I have the templates. Weight wise it is the same as the fibreglass ones, let's see if it is more robust.
I took a photo but it was too dark (black car and black splitter). I'll try again tomorrow
In truth, I'm not happy with the finish, the curved front isn't smooth, but I know what I did wrong and will correct it next time I need to change it. I can knock one up now in a couple of evenings as I have the templates. Weight wise it is the same as the fibreglass ones, let's see if it is more robust.
I took a photo but it was too dark (black car and black splitter). I'll try again tomorrow
Konrod said:
Life got on the way, and then the immobiliser packed up which necessitated a week away at the TVR surgeon. Having got it back I fitted it this weekend. It sits further back so be less open to damage.
In truth, I'm not happy with the finish, the curved front isn't smooth, but I know what I did wrong and will correct it next time I need to change it. I can knock one up now in a couple of evenings as I have the templates. Weight wise it is the same as the fibreglass ones, let's see if it is more robust.
I took a photo but it was too dark (black car and black splitter). I'll try again tomorrow
Well done. I’m keen to see some pics of how it’s turned out. In truth, I'm not happy with the finish, the curved front isn't smooth, but I know what I did wrong and will correct it next time I need to change it. I can knock one up now in a couple of evenings as I have the templates. Weight wise it is the same as the fibreglass ones, let's see if it is more robust.
I took a photo but it was too dark (black car and black splitter). I'll try again tomorrow
Great to see guys taking on projects like this with their cars.
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