Windscreen and side window materials

[Bennie Vorster]

Did any of you ever did the experiment where you drop one drop of fuel on your window or windscreen and you see how the window looks like it is sand blasted and then in another second it cracks before your eyes all the way the fuel spilled.

Some were there must be some material other than the crap material my BB's windows is made of. Please advice.

[ZULU1]

Try contacting DEMS Springfield Park (Durban) or Maizey Plastics countrywide for some alternate materials. I have used some good kit in the past for machinery guards. Lexan polycarbonate is still the best for the purpose you require.

I import helmet visors made from Lexan (sourced from Mud Island) they withstand fuel and crop spayers chemicals..really top quality materials. For your screen they produce shaded also..I understand that a company somewhere in SA vac forms plexiglass Helicopter screens..maybe try Ampaglass also (countrywide). I used to run a Vac forming factory years ago and some interesting alternatives are available.

Bill on the forum will be able to give you some help as he made a forming mould for his Vagabond out of a gas fired Venter trailer turned into a oven..I will speak to him today.

Hope this helps.

eish

Zulu1

[Morph]

Bennie,

you don't really have much choice. THe material to use is Polycarbonate. There is the imported brand called Lexan or some local versions. Maiseys sell a local version called Nexal (Lexan backwards ) The difference is price and quality, Lexan the best and most expensive and the rest.

[Bennie Vorster]

Hi Morph

Does all of them crack when smelling fuel. and is there a way to heat it up before fitting it so it is not so stressed. Or is the only way to just bend it into shape ans rivit it.

Also will I find a template some ware or do I just use the old windscreen?

Another question. Can I fly a BB without its doors ?

[Morph]

Lexan marks with fuel, not sure about cracking.

Don't heat it. Just bend it and rivet it. If the rivet holes are 3.2mm then drill the lexan to 4mm to allow some movement to prevent cracking.

Use the old windscreen as a template.

The busbaby can be flown with doors open and without doors.

[Mogas]

Fuel drips on the windows are a problem. If I get any fuel on my windows I immediately clean it off with a damp soft cloth. So far no marks.
The side windows are particularly vulnerable if you use your tank fuel drains to check for water regularly. These drains are not the best and if they get a grain of sand in them they will drip forever no matter how hard you try to tighten them.
This is another good reason to fit the recommended header tank. I use this to check for water on preflight and have only ever opened my tank drains to defuel.
I often fly with my doors open but find it very windy above 60kts. I have put a 70kt limitation on this in my pilots operating manual.

[Bennie Vorster]

You will not believe the tempo that colouring and cracking takes place after fuel spilling. I had to drain wing tanks to transport the plane and on another incident when de installing the motor the main fuel supply hose were under pressure and sprayed the wind screen. The tensioned points were the bends is immediately cracked.

Special care should be taken when refilling the tanks to not spill and always have a cloth handy.

I wonder If you do not get some type of clear lack spray that you can laminate the windows with so it does not react with the window materials.

Don't know if it is just a BB problem.

[Morph]

No Bennie, all microlights use Polycarbonate as windscreen material and thus all will be suceptable to this sort of problem.
Replacing the windscreen is not a big job. Take the main cowl off (should have Dzus fastners or Rivnuts that screw out easily, remove the boot cowl, also with simple fastners. The windscreen is held on by two rows of rivets on either side and a row along the top by the roof. Very carefully drill these out using a 3.2mm drill. Be carefull not to scratch your paint.

Use the old windscreen as a template to cut the new one. Straight lines are easy to cut using a very sharp blade and a straight edge. Pull the blade along the straight edge a few times, I'd say about halfway through, then carefully bend it around a 90 bend and it will snap along this line.

I find a cutting blade on a grinder works very well and a sanding blade on a grinder is great for trimming edges and sanding around corners. Be aware it does scratch easily, so don't take of the protective cover until you have installed it.

Then as I have mentioned the holes for the rivets must be 4mm with 3.2mm rivets.

I estimate the cost of the Polycarb sheet to be less than R500. I have a very big piece of 2mm, (3.0m X 2.4m) which is twice what I need. You need about 1200 x 500 x 2mm for the standard size windscreen. If you are not in a big hurry we can talk about you buying a piece off me at a very reasonable price of course. Just got to figure about how to ship it to you without scratching it.

[Bennie Vorster]

A Ha Morph, it sound like we might be in for some bussines.Let me know and I'll take it off your hands. We can currier it over night. While there might be a chanse there will be a parsel on the way, you do not have some cloth lying around as well. I have some dope but need some cloth to cover the shall I call it the whish bones for the landing gear the wheels are fitted to.

[Morph]

I'm sure we can make a plan. Let me see how much is left over when I am finished the wings

[Bennie Vorster]

Thank you Morph, PM me when you are ready.