If it is just going to be used for baking out moisture and curing conventional epoxies such as Loctite, Zymet, Armstrong C7, Eccobond, etc, then it is typically no problem to cure them in a standard vented oven.
For flammables such as solvent-bearing conformal coatings and some potting compounds, paints, etc, you should use a Class A (explosion-proof) oven. These ovens have an air-purge system where the exhaust comes on for a certain amount of time prior to the heating elements being activated. This purges the chamber of any potential flammable solvent fumes so the heating element cannot cause ignition inside the chamber. Class A ovens typically come with a blowout panel on the back side of the oven, so if there is an explosion the back panel blows out against a wall. Used Class A ovens are somewhat harder to find, but they are out there. The problem is that most used equipment dealers don't know the difference between a convention oven, a Class A oven, and a hole in the wall (where a Class A oven probably should have been used). :-)
But it is better to be safe than sorry. You don't want to end up with a new company swimming pool, parking lot, or "atrium" or "courtyard".
You might try googling "class A oven, explosion-proof" and see what you can find.
Otherwise, I can recommend Shel Labs if you wanted a nice, large regular oven for less than $5K new. http://shellab.com/product/smo5-shel-lab-forced-air-oven-4-9-cu-ft/
I have at least 14 Shel Labs ovens currently working here at GD and at a couple other client locations, and I have been using these ovens continuously for more than 15 years, with no issues whatsoever.
None have ever failed or gone out of tolerance during that entire time, to my knowledge. I have to characterize these ovens as part of their qualification, and I place a mass such as a scrap circuit board with a TC attached in all of the different locations inside the oven to validate the monitored temperature does not vary by more than +- 3 deg. C, loaded or empty. They pass every time, very uniform throughout. The models I use are the FX-28-2 and FX-14. I am very happy with them.
Contact Kris Meacham at [log in to unmask], he is the rep.
-----Original Message-----
From: Louis Hart [mailto:[log in to unmask]]
Sent: Thursday, December 08, 2016 1:35 PM
To: Stadem, Richard D.
Subject: RE: lab bench ovens
Good question. Only needed for baking PCB coupons and curing epoxy, so my guess is it's just regular oven. I haven't myself put a match to the uncured epoxy, however, or looked at the safety data sheet. Before I do, your experience tell you anything about need for a class A oven in this case? Louis
-----Original Message-----
From: Stadem, Richard D. [mailto:[log in to unmask]]
Sent: Thursday, December 08, 2016 11:19 AM
To: TechNet E-Mail Forum <[log in to unmask]>; Louis Hart <[log in to unmask]>
Subject: RE: lab bench ovens
Does it need to be a Class A oven for flammables (coating/solvents), or just a regular oven?
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Louis Hart
Sent: Thursday, December 08, 2016 9:28 AM
To: [log in to unmask]
Subject: [TN] lab bench ovens
TechNetters, anyone have a lab oven needing a new home? I'm looking for something with a chamber about 70 cm wide, 40 cm deep, and maybe 50 cm high. Temperature up to 200 C would be more than good enough. Thanks for any help. Louis Hart
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