Acrylester Frustration

[Chaz]

I'm really starting to hate this stuff. This stuff chips, breaks and tears out constantly. I hate it. I may never allow a single piece of this evil stuff to darken my shop door again. Ever. If an acrylester project goes well, it's looks great, but I don't see those as much as I throw fails away.

 

[KenB259]

You either have to use negative rake cutters or shear cut. Scraping not the way to go with these.

 

[eharri446]

I have turned a lot of Acrylester and I learned several things.

1. Use a wood rasp similar to this one Wood Rasp to round the corners.
2. Use a tool with a round cutter to turn the blank if you do not have one with a negative rake cutter.
3. Use medium speed
4. Take light cuts until you get close to your final dimensions, then use ABRANET to sand down the remainder.

 

[Chaz]

You either have to use negative rake cutters or shear cut. Scraping not the way to go with these.

Aren't negative rake "cutters" simply scrapers with a negative rake added?

I use those - both carbide and steel. A lot. Especially on acrylics. I also employ a skew with a shearing cut.

:-(

 

[KenB259]

Aren't negative rake "cutters" simply scrapers with a negative rake added?

I use those - both carbide and steel. A lot. Especially on acrylics. I also employ a skew with a shearing cut.

:-(

They are less aggressive, I prefer shear cutting.

 

[Hartwell85]

I rough turn the blank with a standard, round carbide tool using light cuts and slower feed. There is some chipping but I'm not concerned about it at this point. When the blank is about 5/16" larger than the bushings, I switch to a negative rake carbide tool. Light cuts and slow feed works best. Acrylester can be frustrating to turn but light cuts, final shaping with a NR cutter, and carefully finesse the ends adjacent to the bushings work well.

 

[Chaz]

I have turned a lot of Acrylester and I learned several things.

1. Use a wood rasp similar to this one Wood Rasp to round the corners.
2. Use a tool with a round cutter to turn the blank if you do not have one with a negative rake cutter.
3. Use medium speed
4. Take light cuts until you get close to your final dimensions, then use ABRANET to sand down the remainder.

Wow! The rasp made the difference!
It's cheating, of course. A game-changer for me, but still cheating.

I went and turned a couple more pieces. The rasp worked really well. Even at 2k rpm, it removed a lot of material with either face. The end results were very good.

That gave me the idea to try one of my power carving burrs (1/4" sphere medium) with my rotary tool. That worked well, too. That's really cheating.

If you have to cheat to win, just get the job done, dammit!

 

[Kenny Durrant]

There's no rules that I'm aware of in woodworking so there's no cheating just an easier or better way. If you try to pass off a piece as carved but used a CNC that would be lying and cheating.

 

[walshjp17]

Just like there's no crying in baseball, there's no such thing as cheating in woodturning.

 

[ZanderPommo]

Wow! The rasp made the difference!
It's cheating, of course. A game-changer for me, but still cheating.

I went and turned a couple more pieces. The rasp worked really well. Even at 2k rpm, it removed a lot of material with either face. The end results were very good.

That gave me the idea to try one of my power carving burrs (1/4" sphere medium) with my rotary tool. That worked well, too. That's really cheating.

If you have to cheat to win, just get the job done, dammit!

In the Army we lived by "if you ain't cheatin you ain't tryin". If you end up in a fair fight…you did something wrong.

I frequently bring down the size of fragile blanks on the belt sander before putting them on the lathe.

 

[jrista]

I'm really starting to hate this stuff. This stuff chips, breaks and tears out constantly. I hate it. I may never allow a single piece of this evil stuff to darken my shop door again. Ever. If an acrylester project goes well, it's looks great, but I don't see those as much as I throw fails away.

I'd recommend using a round carbide tipped tool, held at a fairly strong sheer angle. This greatly reduces the aggression of the tool, and shaves off the surface rather than chipping away at it. Once you get the blank rounder, you could switch to a slightly radiused square carbide tipped tool, again at a sheer angle, and continue.

You should be able to turn pretty much anything, no matter how hard or brittle, by sheer cutting like this. I've turned inlace acrylester, very hard and expensive trustone, some resin stabilized fossil. One substance I find very hard to turn is "aquapearl" which you can get from PSI. Its pretty amazing stuff, its very hard and extremely, extremely durable...but wow, it is HARD and hard to turn. Takes ages. However its faster with sheer cutting than scraping or turning with any other kind of tool, in my experience.