Parts baking oven for ~$200? - Page 1
Forum section: electronics / general

author: lukego
author_rank: Frequent Contributor
timestamp: November 02, 2020, 09:50:58 am
content: Can anyone recommend an oven for "baking" moisture out of e.g. moisture sensitive parts or complete PCBs that have had an ultrasonic bath?This is for use in a small home lab for the purpose of "by the book" production assembly, specifically to be able to comply with J-STD-033B.1 (https://www.surfacemountprocess.com/uploads/5/4/1/9/54196839/j-std-033b01.pdf). The oven could be quite small e.g. 20cm.I have separate solutions for PCB preheating (Hakko FR-830 hot air) and PCB reflow (Imdes Mini vapor oven) but I don't see either as viable for maintaining a fixed temp of up to 125C for a period of hours or days.I am hoping there is a simple solution for around US$200. Since this would run overnight in a home lab I'm keen on safety and would like to avoid DIY, mods, AliExpress, etc. I have been told that "lab gravity convection oven" is a good set of keywords to start with but they have only turned up larger and expensive options so far.

author: lukego
author_rank: Frequent Contributor
timestamp: November 02, 2020, 10:18:25 am
content: Quote from: blueskull on November 02, 2020, 10:07:34 amI like how you think but in practice the baking oven is far away and needed for other purposes, I don't want to leave a dumpster unit running unsupervised, and the cheap "mini ovens" on Amazon all seem to run on timers up to only one hour. So even being loose with requirements it's not completely obvious to me what unit to look at but maybe Amazon will have the answer.

author: fcb
author_rank: Super Contributor
timestamp: November 02, 2020, 07:29:12 pm
content: I'd be surprised if moisture ingress into the IC's was significant from a short bath.The normal reason to bake out IC's is to reduce moisture PRIOR to mounting and reflow (prevents them forming steam/bubbles which can 'explode' bits off the IC's.We bake our voltage references prior to encapsulation in many layers of silicone conformal coating to reduce/fix moisture level - we use a MEMMERT oven at typically 120-125C for 24hrs.

author: lukego
author_rank: Frequent Contributor
timestamp: November 02, 2020, 08:23:53 pm
content: Here is an interesting option:https://www.amazon.de/-/en/stainless-dehydrating-machine-adjustable-temperature/dp/B07M98P9MR/ref=sr_1_18That's nominally a food dehydrator but it can run 90C on a timer up to 24 hours with auto shutoff. That seems safe and convenient and practical for JSTD-compliant dehydrating of parts, curing of epoxy and soldermask, etc.

author: coppercone2
author_rank: Super Contributor
timestamp: November 15, 2020, 08:06:23 pm
content: keep in mind those dehydrators sold out this summer, people are buying them like crazy for prepping purposes. I just wanted to store some raspberries. Now would likely be a good time to buy unless covid ends this spring.

author: james_s
author_rank: Super Contributor
timestamp: November 15, 2020, 08:15:13 pm
content: I would probably just get a cheap toaster oven and add a PID controller to maintain the temperature, those are dirt cheap now. Personally I've never bothered to bake parts and haven't had any trouble yet. If I were doing a production run or working with an expensive part I'd bake it but for hobby projects I'm less cautious and it has been fine.

author: NiHaoMike
author_rank: Super Contributor
timestamp: November 16, 2020, 04:09:20 am
content: Quote from: james_s on November 15, 2020, 08:15:13 pmIf you're only going to use it for low temperature applications, rewire the heating elements to be in series, helps improve temperature regulation and reduce the peak current through the SSR.