Richard, maybe you did not see my first posting. I went to some effort to point out that there were several classes of devices that were referred to generically as "lab ovens" and I specifically pointed out issues with using devices with temperature ranges that are significantly higher then those that tapes should be baked at. Maybe I should have used "lab class" device in my terminology - and I did mention incubators as one type of device that were good to use specifically because the range of temperatures are in the band of those used for tape baking. As lab class devices they are precise, can produce repeatable results, and are designed for the type of duty cycle that a professional might require for doing work of this sort. I also specifically recommended using an external thermometer that is alarmed so that the variation of any temperature above or below the min/max would set off an alarm.
I do have to say that I am impressed that Richard went to the trouble of actually instrumenting a dehydrator, and that his particular dehydrator on that particular run looks like it did a pretty good job of not cycling too badly. I suspect however, that if I were to do a tape baking comparison where I wanted to bake at 2.5 degrees higher and hold it there for 2 days that it would be hard to do on this device. Typically the temperature range of devices of this sort routinely vary as much as 10 per cent and cycle in those ranges - far too much for this type of application.
And Shai - interesting spin on the headphone analogy. My point, which you missed, was that the same reason you use a quality device that has some precision and is designed for the application in other aspects of a migration process (like headphones), applies to using a lab grade device as well for baking. It is the same logic. I am also pleased to hear that you now finally state publicly that you are a professional, something you have clearly said you are not on other lists, and the basis for your refusal to give your affiliation. So which is it - are you a professional or not? Will you now finally give your affiliation? Who are you anyway? Is Shai a "nom de plume"?
I did clearly waste a large amount of time trying to provide information on different classes of devices that are suitable for doing this type of work to answer Joe Salelrno's question - and that was the only reason why I did it - to be helpful. I will not bother doing that again on this list.
For those who may STILL be interested in pursuing a professional class device that has the capacity and control that I would hope anyone who would want repeatable and controllable results would use - here is an example of a device that might fit the requirements. It is a Fisher Incubator that is used and appears to have been used in a bottle capping application and probably has a large enough cavity for what you may need. They are asking $600 and it likely would be worth while communicating with the seller to ask some questions. There are many more, this is just one I quickly picked to illustrate the kind of unit.
http://www.ebay.com/itm/Fisher-Isotemp-200-Series-Incubator-Model-230G-/380411134753?pt=LH_DefaultDomain_0&hash=item5892454321#ht_500wt_995
I should have also mentioned that new incubator or lab class devices suitable for baking are about $2000 US depending on features, which is pretty reasonable when compared to the prices of other things you use in this field.
Me giving oven advice is also somewhat ironic because as Richard and several of the rest of you know - I am not a big tape baking fan for reasons that have been posted here and elsewhere on several occasions. If you are interested in reading why, one could go through the archive and read about it. But to answer the question of another poster - YES I have baked tapes and YES I have a great deal of experience - if you are interested in my qualifications you need only google me or look at my linked-in page - it is public.
There is a difference between "lashing out" and making ones point in a hopefully persuasive and passionate fashion. This is a subtlety that is sometimes difficult to differentiate when not in person, and one of the disadvantages of a list-serve as a general communications device. There has been no "lashing out" on this email or any other. Passion and expertise yes, lashing out no.
So as they say in Australia - to those of you who love their food dehydrators for tape baking - "Good on Ya". To those who want another option - the information has been provided. Maybe I should buy some Nesco stock!
Jim Lindner
Email: [log in to unmask]
Media Matters LLC.
450 West 31st Street 4th Floor
New York, N.Y. 10001
eFax (646) 349-4475
Mobile: (917) 945-2662
www.media-matters.net
Media Matters LLC. is a technical consultancy specializing in archival audio and video material. We provide advice and analysis, to media archives that apply the beneficial advances in technology to collection management.
On Feb 19, 2012, at 9:51 PM, Richard L. Hess wrote:
> Hi, Tom,
>
> I actually have three American Harvest dehydrators. One is a "Mold Machine" the other is the main one which I have used for years and I bought a larger one last summer for the Mt. St. Helens 14" reel seismic tapes--though you must de-flange the reel to make it fit. Pity.
>
> Anyway, this picture is a sample that I saved, but I do run tests on my dehydrators with recording thermometers to see how they work.
>
> I've seen a lot of nasty eBay stuff (and lots of good stuff), but I'm not certain I'd trust a thermostat or controller in a lab oven that's meant to go to much higher temperatures any more than (or perhaps not as much as) the food dehydrator. I suspect that if the food dehydrator thermostat stuck on, there there is a fusible link in there some where to get its UL label, though I have not dissected one.
>
> http://www.richardhess.net/arsc/am_harvest_fd50.pdf
>
> I think staying within a 2.5 °C window (not plus/minus--that's plus/minus 1.25 °C) is pretty good and all you need for tape baking. That's about +/- 2% Celsius and I hate to think what it is in Kelvins...perhaps +/- 0.006%?
>
> Cheers,
>
> Richard
>
> On 2012-02-19 7:57 PM, Tom Fine wrote:
>> By the way, the American Harvester dehydrator is quite "repeatable" as far as producing playable tapes, many times over many years. Results speak for themselves. But again, horses for courses. There are more expensive and complex ways to skin the same cat.
>
> --
> Richard L. Hess email: [log in to unmask]
> Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
> http://www.richardhess.com/tape/contact.htm
> Quality tape transfers -- even from hard-to-play tapes.
>
|