Eric Lien  have you thought about ditching the glass bed and using a proximity

@Eclsnowman have you thought about ditching the glass bed and using a proximity sensor attached to the XY carriage for bed auto tramming? I’ve never printed directly on aluminum but my initial research turns up that it’s not bad. Just curious.

I do print directly on aluminium heated bed (which does not stick at all) with hairspray on it. It works pretty good.

I have a 1/4 Steel plate on my Ultimaker origional with glass but I only print with PLA. the Sensor is about 4 times the trigger height as aluminum. The only thing is the printer is twice as heavy.

I haven’t leveled my bed in two months. I feel letting the bed come up to temp and reach equilibrium, and using a properly ridged system make auto tramming unnecessary. To be honest I feel auto tram is a bandaid for pour design.

As far as printing without glass, I feel glass is less prone to damage with a head crash, easier to clean, less prone to warping, and down right just plain better. Combine that with the fact it can be easily removed, easily and cheaply replaced I see no benifit to printing on aluminum.

Just my 2cents.

cool, I noticed that the bed was adjustable and I have a ton of issues with my Robo3D with leveling. I read that the Herculien/Ingentis/Eustathios beds were rock solid so I thought I’d ask. If you don’t have to level the bed more than once a month then I’d say it’s probably not worth adding the auto-tramming into it.

The big thing is to allow things to equalize. Also changes in bed or head temp may require adjustment due to the thermal expansion coefficient of the parts: http://www.engineeringtoolbox.com/linear-expansion-coefficients-d_95.html

My experience echoes @Eclsnowman 's. Once I upgraded my Printrbot+ v2’s bed to a machined aluminum plate (with glass on top) and manually trammed it (after heating everything up) I have not had to recalibrate it. And I’m fairly certain the Ingentis/Eustathios/HercuLien designs are all much more rigid, so they are even less likely to need it than my bot. In fact, this is why I have been so lazy about not implementing the induction sensor I bought for it months ago–it simply hasn’t needed it. That being said, I do think it is a nifty add-on for countering minor aberrations, so I still plan to put it on there eventually (or on my next build).