How to Roll Your Own Fingerprints on an FD-258 Card

Rolling a clean fingerprint card is not complicated, but it is not obvious either. Most first-time cards come back smeared or under-inked, and both are fixable once the technique is named. This guide walks through the supplies, the hand prep, the rolling motion, and the slap impressions, using the same method the FBI publishes for law-enforcement booking in its guidance on Recording Legible Fingerprints. A local sheriff's office will do this for a small fee or for free if you prefer. The rest of the page is for the applicant who would rather take ten minutes at home.

What you need

Five items. All of them are widely available.

• An FD-258 card. Either a pre-printed card from a law-enforcement supply vendor or our free printable FD-258 template. You can print this template on normal printer paper. Using original cardstock or printing on heavier paper provides a slightly nicer experience, but functionally they are identical.
• A fingerprint ink pad. The cheap $5 ones on Amazon work just fine. If you're doing more than 10-20 cards, you should get a nicer pad from Porelon or Identicator. Rubber-stamp pads and water-based craft inks are the wrong product. Fingerprint ink is formulated to sit on the ridges without bleeding into the furrows.
• A flat, rigid surface at elbow height. Kitchen counter or dining table. The card should lie flat with nothing underneath that will flex when pressure goes on it.
• Paper towels and rubbing alcohol. For cleaning your fingers and wiping down the edge of the ink pad.
• A second person (optional). Rolling your own non-dominant hand is doable but awkward. A second person rolling both of your hands is faster and produces cleaner prints.

The FBI's CJIS guidance on recording legible fingerprints covers hand preparation first and at length. That is the next section here for the same reason.

Hand prep

Clean, dry, room-temperature hands. In that order.

Wash with soap and water and dry thoroughly. Skip hand lotion for at least an hour before rolling: lotion lifts the ridge detail off the skin and into the ink pad, which shows up as faint, washed-out prints. If your hands are cold, rub them together for a minute. Cold skin produces dry, low-contrast prints. If your hands are oily, wipe each finger with a rubbing-alcohol pad and let it evaporate for thirty seconds before inking.

People with dry, cracked skin often produce the worst prints despite having the cleanest hands. The FBI's guidance for that case is to apply a thin film of water, then blot the surface completely dry before inking. The skin needs to be hydrated underneath, but the surface needs to be dry.

The card layout

An FD-258 card has three zones.

• The demographic block at the top holds name, date of birth, signature, and other identifying fields. This block is irrelevant to the EFT file. SLAP & ROLL reads only the fingerprints, so leaving it blank is fine if the card is for an EFT conversion and nothing else.
• Ten numbered boxes in two rows of five hold the rolled prints. The top row is the right hand (1 = right thumb, 2 = right index, 3 = right middle, 4 = right ring, 5 = right little). The bottom row is the left hand in the same order (6 through 10).
• Four impression areas across the bottom hold the flat or "slap" impressions. Two wide strips for the four fingers of each hand pressed together, and two narrower boxes for each thumb pressed flat.

All fourteen positions are required. Eleven filled boxes and three blanks is not a usable card.

The rolling motion

A rolled fingerprint covers the finger from nail edge to nail edge - roughly 180 degrees of the finger's surface, not only the pad. That is the single detail most first-time rollers miss.

Three motions per finger:

The FBI's training direction is: roll a finger starting from the nail edge turned inward toward the palm, rolling outward. A thumb is rolled from the opposite side, outward toward the body. The easy rule is that every roll ends with the nail edge pointing away from where it started, and the pad of the finger has passed fully across the card.

If you have someone helping you roll, have them stand to your side. It is easiest if your helper holds your finger loosely at the second knuckle and handles the rolling motion while you relax your hand. If you watch your own fingers being rolled, your hand tends to tense up, which often leads to smudged prints.

The slap impressions

The four impression areas at the bottom of the card take flat impressions. No rolling.

• Right-hand four-finger strip: ink the four fingers of the right hand together, press them flat into the strip, lift straight up.
• Left-hand four-finger strip: same motion, left hand.
• Right thumb box: ink the right thumb, press it flat into its box, lift.
• Left thumb box: same, left thumb.

Slap impressions exist so that the matching system can verify the rolled prints above are in the correct order and belong to the claimed hand. In the EFT format generated for ATF eForm submissions, Type-4 files include all impressions (both the rolled prints and the flat slap impressions), whereas Type-14 files only include the plain impressions (a 10-print). SLAP & ROLL supports both formats. Roll all ten finger positions and flat impressions cleanly to keep both options available.

The slap strips are also the least error-prone part of the card. With the hand pressed flat and lifted straight up, there is nothing to smear.

What a good print looks like

Hold a finished card under a bright light and look at each print for three things.

1. Ridge separation. Individual ridges are clearly visible, with white furrows between them. A solid black blob is over-inked and unusable. A faint gray outline with no visible ridges is under-inked.
2. Full coverage. The print extends from one nail edge to the other, with no missing areas at the sides. A print that only covers the finger pad is incomplete. It still scores, but the matcher is working with half the information.
3. No double-printing. Ridges are single, not ghosted. A double-printed finger shows two prints overlaid slightly offset. It happens when the finger touches the card twice during rolling.

The better, fingerprint-level feedback is not visual. It is the NFIQ score SLAP & ROLL runs on every print after you scan the card. NFIQ is a NIST-published algorithm that predicts how reliably the FBI matcher will be able to work with each image. See Understanding NFIQ scores for what the numbers mean and How to tell if your fingerprint rolls are good enough for ATF for the full quality-review workflow.

Fixing a bad print

If a few prints are less than perfect, do not sweat it. As long as the prints are legible and the ridges are distinct, they should pass submission. However, if one or two prints are completely smeared or blotched, you can fix them:

• Cover the bad print with a small white office label (1" × 1" works). Press it down flat.
• Re-ink the finger and re-roll the print over the label, lining up inside the original box.

This is the standard correction method used on law-enforcement booking cards. SLAP & ROLL's image processor treats a label-covered re-roll the same as any other print.

If three or more prints are bad, start a fresh card. Labels stack poorly and add thickness the scanner has to deal with. Printing two or three cards at the start of the session is faster than trying to salvage a card mid-roll.

Do not attempt to scrape, erase, or solvent-clean a rolled print off a card. The card stock lifts with the ink and the result is worse than the original.

Common mistakes

Six failure modes account for almost every unusable card, in rough order of frequency:

• Too much ink. Prints come out as solid black blobs with no ridge detail. Remedy: after inking a finger, press it once lightly on a sheet of scrap paper as a blotter before going to the card. The blotter absorbs the excess; the card gets the clean second impression.
• Too little ink. Prints come out faint and patchy. Remedy: re-ink with firmer, even pressure across the whole finger, and confirm the ink pad itself is not dried out along its edge.
• Dragging the finger on lift. Produces a smeared ridge pattern trailing off to one side. Remedy: lift straight up. Let the card support the finger until release.
• Rolling too fast. Causes uneven ink distribution and skipped ridge detail. Remedy: one slow, continuous motion from nail edge to nail edge. Two to three seconds per roll.
• Incomplete roll. The print only covers the finger pad. Remedy: start with the nail turned fully inward and end with it turned fully outward. The pad of the finger is the midpoint of the roll, not the endpoint.
• Card moving during the roll. The card slides mid-roll and the ridges shear. Remedy: tape the card to the table at the corners, or have a second person hold it.

What happens next