cutting perspex(?) washboards

I recently cut windows with an ocsilating saw (Multi-Master) and a guide and was very pleased with the cut. Obviously, you want to clean up the edge with light sanding.

Perspex is acrylic, which is UV resistant but not particularly impact resistant. Lexan (polycarbonate) is less UV resistant but more impact resistant. Which is better depends on how the closure may be struck. If the Perspex is thick enough it is a good material, but heavy. Down below can be a cave without both the light and the cockpit view that clear doors provide (IMO).
 
I did a lot of this a while back and found that nice sharp wood blades in a jig saw did the trick. Used a squeezy bottle and water with washing up liquid to lube it, also stopped the melting problem. Tidied up the edges with a belt sander. That was 10mm. Much easier to cut thicker perspex than thin, as less likely to crack. Don't remember getting any cracks in about 30 panels.
 
I did a lot of this a while back and found that nice sharp wood blades in a jig saw did the trick. Used a squeezy bottle and water with washing up liquid to lube it, also stopped the melting problem. Tidied up the edges with a belt sander. That was 10mm. Much easier to cut thicker perspex than thin, as less likely to crack. Don't remember getting any cracks in about 30 panels.

Good point on the water in a spray bottle. Like cutting oil, it is something we commonly forget.

I've found that I can cut VERY thin perspex with a MultiMaster, so long as I take light back-and-forth cuts, similar as one does with an abrasive wheel in steel if one wishes to neatly follow a line. Obviously, a guide helps (straight edge), which is easy with an oscillating saw.

If you don't have one, get one, You'll find many uses. Great for plunge cuts and places that are hard to reach. At home too. Every contractor has one and they use them a LOT during remodels. Many brands. Mine is actually by Dremel. The first tough problem will pay for it.
 
Depends on how much you like to bodge things i suppose.
This is PBO to be fair so it makes sense to lean towards a bodge rather than buy, even if I do agree with you.
Perspex is acrylic, which is UV resistant but not particularly impact resistant. Lexan (polycarbonate) is less UV resistant but more impact resistant
There’s a post on these forums somewhere from someone who worked at Lewmar (who make port lights etc. ) and I believe he said Acrylic is what they use and Polycarbonate scratches moments after you finish the job. I may be misremembering that but he was pretty clear on what Lewmar use and why.
 
Does nobody use a handsaw any more except me?

I had to replace an acrylic sliding hatch, so I cut the old acrylic (damaged at the edges only) down to make an acrylic washboard. Ordinary wood handsaw going carefully. I then used a block plane with a good sharp blade to get absolutely smooth edges - definitely better than I could achieve by filing - and put a subtle little bevel on the corners. It doesn't seem to have been too unkind to the plane blade (I was expecting to have to resharpen after, but it did a few more jobs OK first). Not sure if this is bodging, but the result doesn't feel like it.
 
Does nobody use a handsaw any more except me?

I had to replace an acrylic sliding hatch, so I cut the old acrylic (damaged at the edges only) down to make an acrylic washboard. Ordinary wood handsaw going carefully. I then used a block plane with a good sharp blade to get absolutely smooth edges - definitely better than I could achieve by filing - and put a subtle little bevel on the corners. It doesn't seem to have been too unkind to the plane blade (I was expecting to have to resharpen after, but it did a few more jobs OK first). Not sure if this is bodging, but the result doesn't feel like it.
From way back, cutting aircraft windshields to size, (think VERY expensive.. so a bit nerve shredding..) there is a real risk that a hand saw might start a crack because of the 'possibly' uneven application, whereas a power tool is more consistant.
Same with a plane, I found the belt sander, a small Bosch, did a very good job on the edges. Since they had to be polished, after the belt sander, with various grades of W&D paper.
That project was a spiral marble staircase with perspex panels between each marble upright, topped off by a brass handrail in 50mm tube. Same for the mezzanine over the living room. So the panels then had to be heat formed to the spiral shape. Got quite interesting, after I chatted to the arquitect who designed it, only to find he had no idea who might be able to make it... Since the builder had abandoned the project, I had to get quite inventive to get it all finished.
 
Sounds like a plan...

Buy a persepx cutting blade, carefully cut the old (probably scratched, clear, brittle persex at an angle Perfectly straight and parralel.

Assuming it didn't break.... Sand the cut edge with 60 grit, progressively coming down in grades to 600/800, then polish with cutting compound. Taking care to keep the edges perfectly straight and aligned, to it forms a seal.

Or, order a couple of pieces of nice new, bronze tint (gives a bit of privacy) perspex, cut to size, polished edges and ready to fit.

eeny meeny miny moe............... :unsure: 😉
Lot of assumptions there. No suggestion by the OP there is anything wrong with the one he has already given that it has been replaced by wood ones. one pass through a table saw, a bit of polishing and job done. Exactly what I did with the one on my Bavaria 37 which was then 8 years old in the Med sun. 10 euros to the workshop for use of the saw. Quick quotes for 2 500*600 10mm acrylic around £140 before cutting the angles and polishing.

Also worth considering cutting 70/30 so the bottom part can be left in when sailing.
 
Lot of assumptions there. No suggestion by the OP there is anything wrong with the one he has already given that it has been replaced by wood ones. one pass through a table saw, a bit of polishing and job done. Exactly what I did with the one on my Bavaria 37 which was then 8 years old in the Med sun. 10 euros to the workshop for use of the saw. Quick quotes for 2 500*600 10mm acrylic around £140 before cutting the angles and polishing.

Also worth considering cutting 70/30 so the bottom part can be left in when sailing.
Quite, the bloke is on his boat in Portimão, so likely limited options on tools.
 
Lot of assumptions there.
Indeed, see below. You don't know the condition, but it's very unlikely it's going to be "as new". He may not have a table saw, or access to one (good suggestion though).
No suggestion by the OP there is anything wrong with the one he has already given that it has been replaced by wood ones. one pass through a table saw, a bit of polishing and job done. Exactly what I did with the one on my Bavaria 37 which was then 8 years old in the Med sun. 10 euros to the workshop for use of the saw. Quick quotes for 2 500*600 10mm acrylic around £140 before cutting the angles and polishing.

Also worth considering cutting 70/30 so the bottom part can be left in when sailing.
On what do you base the assumption that the OP needs 2 500*600 panels ? Seems very, very unlikely he has a single washboard, 1000*600*10mm !! Besides, it's nothing like £140
 
Indeed, see below. You don't know the condition, but it's very unlikely it's going to be "as new". He may not have a table saw, or access to one (good suggestion though).

On what do you base the assumption that the OP needs 2 500*600 panels ? Seems very, very unlikely he has a single washboard, 1000*600*10mm !! Besides, it's nothing like £140
This is the OPs boat yachtsnet.co.uk/archives/sadler-290/sadler-290.htm 1000*600 for the companionway does not look far out. This is a sample quote for a single piece with no cut and no polishing perspexsheet.uk/clear-000-perspex/ so £150 for finished job of 2 pieces with a 45 degree cut and polished edges including delivery would not be far out. If his current unused one piece acrylic washboard is in good nick a few quid to a workshop and a bit of work to attach a batten would do it - just like I did.
 
Depends on how much you like to bodge things i suppose.

Goodness, I didn't know you were supposed to polish the cut edge.
Next thing you'll be telling me I wasn't supposed to use the piece of perspex I found in the marina skip!
I found a piece of perspex(?) in a telephone box.
Then I found a boat (AKA a marina skip) to go with it
I like to bodge things a lot.
 
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