Processing Wood

[II2None59]

Hi! This is my first post to the message board and I'm hoping someone can give me some ideas. I've spent some time online and searching through my various materials for information, but as I get conflicting methods I thought I'd see what might be a favorite among some of you.

I have a piece of wood that was collected at a scene I worked, one in which some suspects were alledgedly attempting to gain entry into someone's home. The stick measures about 26" in length so I'm thinking it might have been part of a table at some point. (Not the first time somebody has used an object for something it wasn't intended for! ) The wood is smooth/semi-polished in some areas, worn in others (as in having scratches).

I have read about using the super glue method, ninhydrin, DFO and physical developer. Any suggestions? I have access to all these chemicals as well as SPR, iodine, Rhodamine 6G, etc. and we have an alternate light source available as well. As far as lifting materials for "rougher" textures, we have Mikrosil and gel-lifts. I'm also wondering -- if ninhydrin or DFO is used, do you also use the other steps (iodine, ninhydrin, physical developer or ninhydrin, DFO, etc.). Or is there a simpler method I'm just not thinking about.

Thanks to everybody for your time!

[Danny L. Harness]

I would not use any chemical method on a non-absorbent surface such as finished wood. These processes are used for absorbent surfaces. I would use Super Glue followed possibly by photography and then a latent print powder. After powder has been applied (and possibly photography) I would use the casting material or possible simple lifting tape being careful to put the tape into the recessed areas if possible. Good Luck!
Danny

[Spartacus3131]

It sounds like you have two different types of substrates on the same object. IF you have one available or can take your evidence, safely, to one, I recommend use of a KrimeScope (sp?). It uses UV light with other technology to make prints fluoresce and it can be used during daylight conditions. The value of this approach is if you can locate the prints PRIOR to processing you can determine whether it's the polished portion or the rough portion and make an appropriate determination for processing based on your training and reading.

[Hillary Moses]

Hi! I have this problem all the time in Hayward, CA. Lots of juvenile perpetrated 459s in which baseball bats (wooden, worn, parts with finish and others raw wood) were used for gaining (not-so-subtle) entry to the home. I recently tried a deviation from my normal processing routine. I first lightly dusted the bat with a fluorescent powder. This was great, because it is such a light application, it does not hinder other processes. I then used ninhydrin on the porous, unfinished surfaces. I put the HFE7100 ninhydrin formulation in a small wash bottle so I had better control over the amount dispensed. Here's a summary of what has worked for me so far in this situation:

1. superglue, powder (magna/fluorescent), ninhydrin on unfinished spots

2. ALS, superglue, fluorescent dye (on the finished spots), ALS, powder

I guess it depends on the finish of the stick. If there is a lot of finish remaining, I'll use method #2. If it's mostly raw wood, I'll use #1. Good luck!

-Hillary Moses

[tseguin]

I've found that RTX (RuO4 in Novec) consistently gave me the best and most consistant results on wood, especially wood used in furniture and construction grade wood, e.g. studs. You will need a good digital camera and software such as Adobe Photoshop (or maybe GIMP) to separate the ridge detail from the wood grain. If on a heavily laquered surface cyanoacrylate should work well for you.

Tim Seguin
MOIA webmaster
webmaster@moia.org

[II2None59]

Thanks Danny, Spartacus, Hillary and Tim for all your suggestions. I'm going to go back through our chemical cabinet, double-check what all we have, and then take it from there.

I was sort of surprised when I read on one website about using physical developer or DFO and other such chemicals for processing wood. That had never occured to me as I normally use them in processing paper products, etc. But as I'm always on the lookout for new methods, I was curious. I'm hoping to work on the object this week if we don't get too busy on our shift, so when I process the wood, I'll be sure to get back to the Forum and let you all know the results.

Thanks again!

[Norberto Rivera]

One method that I didn't see mentioned is iodine fuming. (Pls forgive me if someone mentioned it already, I haven't had much coffee yet today ) I have had good results on unfinished wood before. As someone already mentioned I would go with the CA fuming on the finished portions afterwards coupled with the dye stain of your choice. I've had great results lately using RAY mixture (basic red #28, Ardrox, Yellow #40) and visualizing the developed prints using a 505nm light source (green) and 520 nm filter (red). Good luck!