Triumphrat

Curt955i · 05-08-2008

Patience, and practice. I think I may try my hand at this the next time I'm really bored. I have a pretty much unlimited supply of pieces to experiment with, It's been awhile since I played with the techniques so I'm sure I'll destroy some perfectly good material too

but on the bright side it won't cost me anything.

graeme · 05-16-2008

Just thought I'd pop an update in here as to how my screen reshaping went.

I bought some 5mm perspex from a plastic wholesaler and cut it to shape. I heated it for 15 minutes at 180 degrees C. The perspex is very workable at that temperature and forms readily.

I made myself a jig in the same shape as the Tiger Tall Screen and clamped the hot perspex into it to shape it:

I then cut the perspex to a more attactive shape and mounted it:

As this was just a protoype it is very rough around the edges, and the perspex is a bit rippled. It is very hard to work with and to keep looking neat and tidy, but with more practice I think it's possible.

The screen has made a massive improvement to the buffeting problem I had, so I'm pleased, even if it looks a bit "ugly".

Curt955i · 05-20-2008

Interesting project Graeme, I had a completely different picture in my head while I was reading through the thread and commenting. I was under the impression you were building a new windscreen from the fairing up. I can't say I love the way it looks, but if it's functional who really cares it's a prototype model anyways

With enough practice and experimentation you'll have a compound curved, full on custom screen on there in no time.

I just had a thought that may help with future models. If it were me I would cut the perspex to the desired shape before bending it. My reasoning for this is that it is much easier to achieve consistent edging on flat material than on curved material. Also if you do all the cutting and edging before heating you can leave the protective paper or plastic on the material and minimize scratching. At work I use a 1" wide belt sander to clean up rough cut edges on pretty much all types of glass and perspex. Like shaping the material, it takes practice to get a consistent edge. The easiest edge shape to make is a "flat grind" it's just a 1-2mm 45 degree chamfer on both sides of the material and a flat spot between them. A "pencil grind, or polish" is an evenly rounded edge that IMO looks better than a flat grind but takes much more practice to make look right.

As far as the how to goes, I would use a clamp or two to secure the material to my workbench with as much of the edge hanging off the table as possible. Using a 120 grit belt start by making the edge nice and flat, then finish with the 45 degree chamfers. There will be some melted material that sticks to the edge. To remove it simply take a fresh flat razor, hold it perpendicular on the edge and drag it along the edge. Always keep the sander moving back and forth so you can keep an eye on your progress, also use light pressure and a slow speed setting (if your belt sander has a variable speed setting). A conventional 3" wide belt sander will work if you don't have a 1", but it's a little bit clumsy, and hard to use moderate pressure with. The best tool for this job is an upright belt sander that lubricates with water, the one I have at work is a Bee metal sander most people don't have one kicking around in their backyard shop though. Another tip for using the 3" sander is to use a finer belt, it will plug up quicker but it won't chew through the material as quickly. If you want when your satisfied with the shape of the edge yo can make it glossy by heating it lightly with a small butane soldering torch. When doing this you'll want to keep the heat moving pretty quickly to avoid bubbling the material. Also the heating in the oven stage may have the same effect on the edges so this last little step may not be necessary.

graeme · 05-21-2008

Curt,

Some great tips there, especially the one about cutting it first before shaping it - Why didn't I think about doing that

I've seen a demo of people heating the edge with a blow torch to smooth it out, but didn't have the confidence to do it.

This stuff is quite cheap so - practice makes perfect

Thanks.

Curt955i · 05-21-2008

Graeme,

I'm happy to share my experience with the things I know in exchange for information about things I do not

I've learned quite a bit from this site in the short time that I've been visiting it so I'm glad I found a thread that I could contribute something useful to.

The blowtorch trick is actually pretty easy, try practicing the edging techniques on a piece of scrap and then finishing it with a a torch. To elaborate on my previous post use a small butane torch designed for electrical soldering as opposed to a larger one that uses propane designed for soldering plumbing. The large ones are harder to control, although if adjusted to a small flame they can be effective.

Feel free to pick my brain if you have any difficulties along the path of experimentation

Tbirdnz · 05-23-2008

Have you considered cutting the screen down to a more rounded level ? Similar if not lower than the 08 models ?

I think the 955 Tiger's screens direct the wind onto you giving a buffering effect that most Tiger riders complain of. It's obviously those with a certain height that are affected most.

Re-shaping the screen lower, whilst it doesn't offer the same protection at least disperses the concentrated wind buffering. I'm thinking more fly-screen design than the present fuller screen.

You don't have to destroy your original screen for that, make a mock-up with some bendable plastic or perspex and fit it. Experiment with height. Then if you're happy cut or get the original screen cut to the same shape.

On a looks basis I think it would also improve the 955 Tigers appearance.

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Ride on !

graeme · 06-01-2008

Hi All,

I finally got round to making the final version (I think) of my GRA(eme) VARIO Screen.

I'd like take this opportunity to say a BIG THANKS to Curt, and everyone else for their help.

This time I took Curt's advice and cut out the shape before shaping it and that did the trick, an accurate, well shaped edge. I left the protective film on until all the cuts were complete and therefore no scratches. I put it in the oven for 15 minutes and when nice and floppy I laid it directly over the MRA Vario spoiler and just held it in place until it hardened. No fancy jigs this time. Drilling the holes was nerve wracking as I was worried it would crack, but it was ok.

It's a slightly different shape to the prototype and slightly higher.

You can't really tell from the photos but there are no ripples, marks or bubbles in comparison to the prototype which was a mess:

I haven't had a chance to test it yet as the weather is crap. Hopefully will get a chance to test it before my trip to Europe on Wednesday. It wouldn't be very good if after all that hard work it didn't work !!!

EDIT: Had a chance to test it today and it works really well. All the noisey and painful buffet goes over the top of my helmet and all is calm beneath the screen.

Cheers.

Curt955i · 06-02-2008

Looks great graeme!

Nice job.

Now can you build one for my RS?

katblack · 06-07-2008

I found that the low pressure zone created by window on my 2002 (tall factory wind screen)
was due to the relieve opening at bottom of window, it was to small. I removed a total of 1/4 inch following same contour and the buffeting stopped. I have since put a cee bailey on and found it to be very similiar. Also removed a small bit 1/8 inch. Made a difference.