Plexiglass Routing: RPM and Router Bit Question

OK folks, Referring to the photo, I did my first plexiglass routing yesterday. I made some foundry pattern letters .06" deep on .125" thick acryllic plexiglass. the routing seemed to work but I noticed I got a buildup of melted plastic on my router bit. I suspect I'm running the rpm too fast. I had the router set at 3 1/2 out of 5. I also used a spiral bit that I'm unsure what it's designed to cut. this bit came with the Openbuilds CNC machine I bought.

What I really am trying to do is route letters with a slight pattern draft angle: about 2 or 3 degrees. Interestingly enough, although the bit I used had no angle in it, it did pull from the sand in a test mold I made last night. But this is pure luck. Ideally I need a bit with a little angle to it.

So here's my questions:
1. what speeds are recommended for acryllic?
2. Can anyone recommend a good tapered bit with just a couple of degrees to it for what I'm doing.

 

Thanks! I'm going to order one of those and try it slower.

 

Brrain, That looks like it's be a good roughing bit for me. I did order the recommended tapered one last night and will report back to the group. Much, if not most, of my stuff needs to be pretty fine detail and tapered, hence the 1/32nd bit. But I will need to route larger surrounding areas of the pattern and the bit you recommended will be faster.

 

Well that expensive bit lasted just over 20 minutes at the lowest router speed and cutting at .03" deep.

 

No, it was the tapered bit. I had the router on the lowest speed and I think the problem was when I turned on the shop vac, the router quit spinning and it snapped the bit. They are both plugged into the same power strip. I haven't tried yours yet. the stuff I do it pretty detailed so I need the 1/32nd bit.