Making a slot

[ddub]

I am looking at a project that I will be putting a 7/16 slot in Polyethylene plastic.

In my R & D piece I used the router. I am wondering if a Dado blade would be easier? The length will be about 4 feet on some pieces. I have never used a dado blade.

Or?

[rjent]

How accurate does it have to be? I would think a router would give you a "cleaner" slot.

[garys]

My experience tells me that the router should work better than the dado blade. I find that dado blades are more prone to chipping the material than the router would.

[wa2crk]

A router would be my choice as well. This may be one of those chores where the SS would be more advantageous. The high speed of the router might cause some melting but the router bit in the SS would provide a slower speed to reduce the chance of the plastic melting.
Bill V

[JPG]

Speed is your enemy here. Both cutter rotation and feed.

I have cut plexiglass with 9"(Mark 5) blade and it worked well. Plywood blade as I recall.

Now that required a straight cut referenced to a straight edge(rip fence used). Also 'cross cut'(miter gauge).

I was not cutting slots however.

I think the worst would be polystyrene.

[richardrouse]

For what its worth, I've used my jigsaw to cut slots in plastic. Slow speed and painters tape to reinforce the area being cut

[Gene Howe]

router, no doubt.

[reible]

I guess my question back at you is:

Did you have a problem using the router method?

If it worked then you are good to go. If not then what problem did you see?

If it were me I think I would make sure I had a plunge bit of the correct size and do it in one pass (this is assuming you need to plunge to start the cut). I would also make sure I had a guide that keeps the cut straight and true.

I've cut this material before and as I recall it seemed to machine quite well and provide a lot of "snow".

Ed

[ddub]

Accuracy. Not a big deal. Just has to look decent enough so as not to look like a total noobie did it! LOL

I am making light fixtures for my paint booth, and the plan is to install LED lights in the grooves which will be about 4 foot long.

Initially I had thought of using the plunge function of the Shopsmith router to do the slot, but the speed isn't quite up to par and it does leave a bit of a jagged edge and chattered a bit. Plus the table might end up being a bit on the small side. It will do it, but just thinking if there is a better way.

I actually thought that the Dado might do a nicer cut. I guess I am wrong. Running it across the table saw just seemed a little easier when I thought about cutting 4 foot lengths.

Yes I do have a hand held plunge router. Yes I do have a adjustable bars to clamp onto the material to give me a nice straight line. So, that is a method that I can also do. Just hadn't thought of it.

Here is a R & D piece. About 6 inches long.



Here it is above my work bench with no other light.



Doing calculations, 4 feet of this LED should put out about the same amount of light as a 4 foot fluorescent. Also should be fairly sunlight color correct. And will not take up the space of a fluorescent so I can keep the booth closer to the wall and add additional lights fairly easy as I see fit.

Thanks!