Forced air powder application

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Kasey Wertheim
Posts: 161
Joined: Sun Jul 10, 2005 6:55 am

Forced air powder application

Post by Kasey Wertheim »

I have searched online as well as the Hamm index for an article or articles I remember from my LPE training days involving the application of black powder using a forced air technique. Imagine your keyboard forced air application canister only it delivers an aerosol application of powder across the surface. I remember discontinued use due to non-ideal development when compared to brush application. And I remember the article in a "historical" context rather than reading about it as a present-day technique. However, I can't find the reference. Ring a bell with anyone?
Ernie Hamm
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Location: Fleming Island, Florida
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Re: Forced air powder application

Post by Ernie Hamm »

Not sure if this qualifies as 'forced air technique', but a form of aerosol processing was mentioned in the early IAS training material. A applicator device was also sold through IAS by way of the FP&I Magazine. It was called "The De Vilbiss Powder Blower" and was an atomizer device for processing large areas. Such processing is illustrated in Lesson VII (Latent Finger Prints) of the IAS course.
Terry A. Smith
Posts: 34
Joined: Fri Jul 22, 2005 4:38 am
Location: Niagara, CANADA

Re: Forced air powder application

Post by Terry A. Smith »

Hi Guys.

Pictured are a couple of DeVilbiss powder blowers from our "Vault of Forensic Secrets". For grins I attempted to develop a test impression on my office window this morning. I will agree with Kasey's comment regarding "non-ideal development". My window looks like it was hit with a muzzle blast from some War of 1812 ( yeah, the one where Canada sent you boys packing ) firearms relic. Mind you, my application technique may have been a tad on the agressive side. I probably also should have been wearing self-contained breathing apparatus, judging by the amount of powder which seems to be all over my desk now !!

The DeVilbiss company is still manufacturing compressed air tools mostly, I think, for automotive paint applications.

Cheers from Niagara,
TAS
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josher89
Posts: 509
Joined: Mon Aug 21, 2006 10:32 pm
Location: NE USA

Re: Forced air powder application

Post by josher89 »

Henry Lee's book and Scott's Fingerprint Mechanics both mention the use of toner ink (from copiers) with the use of an atomizer as a form of latent print development. I haven't used it but I know from changing toner cartridges in our printers that the powder is superfine and gets all over everything.
"...he wrapped himself in quotations—as a beggar would enfold himself in the purple of emperors." - R. Kipling, 1893
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