Using perspex as ts sled runners?

[JWD]

Hi all, just hoping i could get some quick advice on using perspex as runners on a new table saw sled i'm making, my thinking is that they might wear a little slower, run smoother and not expand and contract as the wooden ones might.

I've got a piece of perspex 6mm lying around that i think i'll use, but if its not a good idea then i'll stick with oak.
cheers
joe

 

[andersonec]

Perspex is fine, remember your sled is not running on the perspex they are just there to guide your sled, the sled slides on the table but make sure there is no slop with your perspex in the slots, they must run smoothly but have no sideways movement.
Here is possibly one of the better table saw sleds on youtube.

https://www.youtube.com/watch?v=GZuyC7udVjs&t=152s

 

[woodbrains]

Hello,

Perspex in theory is fine, but I think you might have difficulty in fine tuning strips made from it, to give a smooth, sliding fit, with no play in the mitre slots. Wood has the advantage of being easy to plane a couple of thou off to sneak up on a good fit. Perspex, (acrylic) is very tough on planes and dulls the irons almost immediately, so planing for precision is out. I think it would be too hit or miss trying to cut the acrylic on the table saw for a perfect fit, the tolerance between it being just to big to fit the slots and being too sloppy is minute. I suppose you could use wet and dry abrasive stuck to a block, but it might be difficult to keep the strips straight and true.

Wood as narrow as that needed (3/4 inch or less) for this purpose is not going to give a lot of trouble with seasonal movement, especially if you use quarter sawn stuff.

Mike

 

[mindthatwhatouch]

I've just used some Corian, maybe an option.
I have no idea how it's going to wear, sure you can find a kitchen place locally​ that will give you an offcut.

 

[Hornbeam]

I am sure perspex will work but i think you would be better using tufnol or another engineering plastic
ian

 

[Steve Maskery]

Personally I wouldn't use perspex, I don't see any benefit and it is troublesome to work (from a blunting point of view).
Given the small size and likely only occasional use, I don't see what is wrong with a strip of maple or ash. I wouldn't use oak, if you leave the sled on the table overnight you might get some rusting, it doesn't take long.
On one of my sleds, I made the runners a bit loose and inserted small brass screws into the sides. These could be adjusted until I had the fit I wanted. They worked well.

 

[novocaine]

use 2 thin wedges instead of a single piece, leave one long so you can slide it in once on the saw, fit the other the same as you would a single piece slide.
slide the other in till there is no movement but the sled slides free, clamp it by sliding the sled till you can get a clamp on. flip it and screw it in place. perfect fit, every time. bit more complex to do than a single piece of wood though. I have 1 sled done this way, the rest are all a strip of whatever.

 

[lurker]

One of those 2 quid white plastic cutting boards from Tesco does this job really well.
Not sure what plastic it is, but it machines & hand planes very nicely

 

[novocaine]

that would be HDPE. same stuff as milk bottles.

 

[rafezetter]

One of those 2 quid white plastic cutting boards from Tesco does this job really well.
Not sure what plastic it is, but it machines & hand planes very nicely

99p from Ikea, they also work as mitre slot runners / blocks for featherboards etc.

 

[JWD]

Hi Guys, many thanks for your responses!
in the end i did go with the perspex, it works pretty well! I used another piece to re-do the mitre gauge, as the ts200 gauge is notoriously terrible, and did indeed do the brass screw idea and it works great with zero play!
HDPE is a fantastic idea i wish i'd thought of, i just had the perspex lying around.

Does anyone know where to get HDPE from in the uk, for T.S Fences etc? ive never been able to find it!

Cheers again fellas

 

[novocaine]

knowing it's actual name helps.

http://www.industrialsuppliesco.co.uk/s ... o_s=gplauk

it's used in a number of industries as a bearing surface.