radio box lids - rc

[colin]

what is the best clear lid to use for the wtc. acylic or perspex? does one work better than the other?
sorry if it seems to be a stupid question but all i can seem to get easily is acrylic.

[JWLaRue]

Hi Colin,

Perspex is the trade

Hi Colin,

Perspex is the trade name in the U.K. for polymethyl methacrylate. It's also known as Plexiglas, Perspex, Acrylite, Acrylplast, and Lucite and is perhaps more commonly called acrylic glass or simply acrylic.

So in this case you're really talking about the same material.

This is a good material to be used for WTCs. It's not nearly as brittle and prone to cracking as polycarbonate.

-Jeff

[Guest]

Jeff and others,
Polymethylmethacrylate is acrylic,

Jeff and others,
Polymethylmethacrylate is acrylic, and it is more prone to cracking than polycarbonate, which is the generic name for Lexan. Lexan is less prone to breakage and/or chemical deterioration.

[anonymous]

Hi Colin,

I take it you

Hi Colin,

I take it you are writing from the UK.

Polycarbonate sheet is IMHO better than Acrylic for all the reasons given. It is not cheap but you can get it from Glaziers etc. (It is commonly used for security glass etc)

Acrylic tubing (for WTCs) is available from Trylon in Northampton (Google it!)

David

[JWLaRue]

Art,

If I remember correctly, a

Art,

If I remember correctly, a polycarbonate would be preferred if the material needs holes drilled into it since acrylic propogates cracks much easier. On the otherhand, arcylic is more resistant to breaking.

For WTCs that use chemicals like Propel, a polycarbonate is the way to go.

So it would perhaps depend on how the material is to be used.

Have I got that difference correct?

-Jeff

[Guest]

Jeff,
Not quite right. Acrylic is

Jeff,
Not quite right. Acrylic is more brittle and subject to fracture under stress, than the stronger polycarbonate, (Lexan). The advantage of acrylic would be lower cost and slightly better rigidity. With no chemicals, (like Propel, which will cause crazing of acrylic), and using 1/4' thickness, it would be a good material for a radio box lid.
Personally, with the standard 1/8" wall thickness, I would not use an acrylic tube again for a WTC. One cracked on me when I was inserting the end cap. I will only use Lexan polycarbonate for a watertight cylinder, even though I don't use Propel.

[anonymous]

Jeff,

I built my first home

Jeff,

I built my first home made WTC from acrylic. Everything was fine for awhile and then every place I drilled a hole it started to fracture like automotive glass hit with a rock.

Ever since switching to poly carb this has stopped completely. In fact I put some scrap tubing in a large vice and was unable to break it. It cost more but you'll never be looking over your shoulder.

Hope that helps,

Steve

[JWLaRue]

....like I said]http://www.subcommittee.com/forum/icon_smile.gif

-Jeff

....like I said]http://www.subcommittee.com/forum/icon_smile.gif[/img]

-Jeff

[Guest]

I have a 35 year

I have a 35 year old 1/4" thick acrylic lid with holes carefully drilled around the edge about every 2". I use an electric drill to remove and replace the holddown screws to save time, and make it easier, every time I have to service the electronics or charge the batteries in "Flipper".
Acrylic serves well for this purpose, even with holes drilled through it, although Lexan would be stronger.
The 1/8" thick acrylic WTC, mentioned in my post above, cracked even though it had no holes drilled in it.
If you drop an acrylic WTC, it will probably break. If you drop a Lexan WTC it will probably bounce. Not very scientific, without giving the specs, but most people will get the idea.

[anonymous]

Jeff,

I hear you. No problem

Jeff,

I hear you. No problem here.

Art I tried to break it. Hit it with a hammer. Ran over it. Tried crushing it in a vice. It melts ok but it is nearly indestructible!

Steve

[chuck chesney]

Hi guys,
Log me in with

Hi guys,
Log me in with the Lexan group. I have used both acrylic and Lexan, and there is no comparison. It is'nt even close...Lexan costs about twice what acrylic costs, but is basicly bullet and bomb proof. No worries when the sub is in the water with Lexan components...constant worry in the back of your mind with acrylic.

Chuck

[stoene]

I know they use polycarbonate

I know they use polycarbonate (Lexan trade-name) in industrial applications where safey guards/partitions are needed. Very strong. You can get the specks at McMasterCarr Type in polycarbonate or acryllic, choose type, etc. Also, a good place to buy this stuff. They sell small quantities.

[Guest]

I've used acrylic for my

I've used acrylic for my cylinders- not a problem.

Lexan or polycarbonate tubing is very hard to find in the UK, whereas acrylic is relatively easy to source.

It is more prone to breakage than lexan, but I can easily sit on my cylinders (all 12 stone of me), so just how much strength do you need?

What the heck are you folks doing to it to make it break up?!

You need to use fine and very sharp tools for cutting acrylic, then it works just fine. Drills should be sharpened differently for acrylic, than for cutting metal.

I cut my cylinders use a metal cutting blade on my bandsaw, then I turn the ends up on my lathe. The lathe is set to about 450 RPM, and I make sure my cutting tool is very sharp, and centred accurately. I take light cuts, and the sprue comes off with the sound of hissing steam- almost singing.

Having said all that, if you can get polycarbonate easily, use it, it's just about the toughest plastic on the market (they use it for riot shields), but don't fret if you can only find acrylic- it's more than upto the job (OTW use it for their WTC's, I don't hear any complaints about their products).

Incidently, you can make very fine wtc's using PVC drainpipe or ABS tubing.

So what if it isn't clear, it's dirt cheap, and very easy to work with even crude tools.

Andy

[Guest]

For anyone in the uk

For anyone in the uk here's a link regarding polycarbonate.

http://www.gcip.co.uk/EP/lexan.htm

Also andy sub culture.

Just wondering i was offered some gas tubing 6mm thick. 120mm dia, & 2000mm in length

do you think this would this be suitable for a wtc?

Best regards


adam

[Guest]

More than strong enough, a

More than strong enough, a little bit on the thick side mind- so heavy.

Have you got a lathe?

If so, you could always turn it down- 3-4mm is more like it.

Andy