Kev Williams
03-11-2015, 1:25 PM
I post this for anyone who may be contemplating something similar... ;)
One of my ongoing engraving jobs involves engraving aluminum boxes, cases and housings. Most must be rotary tool engraved, due to several reasons, such as the aluminum and engraving requires painting, but mostly because of their size. Many of these items are black anodized, but are typically too large (tall) to fit in most typical lasers. I have a NH 3400 cylinder engraver, and it's vertically adjustable clamp allows me to rotary engrave items up to about 16" tall. This works well for one of my steady customers. But I have one customer who custom builds aluminum aircraft component housings, which are black anodized but rather large, typcally 24" to 28" long x varying H&W's, the largest is usally 18" x 10". My job is to engrave the top of the LONG side. How I've been doing these for the past 15 or so years is with an old New Hermes IRX-IV manual pantograph, which is clamped to an old school desk, which has a large aluminum plate screwed to the back, which serves as the surface to rest the housings against. The housings are held in place against the desk with a ratchet strap that goes completely around the desk. It works okay. But the engraving is a slow and tedious process, involving several master moves and usually one housing move due to the limited engraving area of the pantograph. Engraving across the top of an 18" wide part requires an engraving master at least twice that long (at 2:1 ratio), the machine doesn't have that much 'reach'. So I just fit each "text unit" at short intervals, and move the master to line up each unit. I eventually run out of pantograph travel, then have to move the part. This text-shifting process is also necessary vertically as well as horizontally...
So, whenever these parts come in, I cringe... ;) Pure time-eating, white-knuckle, proprietary work.
If only I could laser engrave these things...
Enter my cheap Triumph laser, the one I bought without a movable table. It's paid for itself at least 3x over so far, and I have my work-arounds for the non-adjustable table. Since the day I got it I've thought about cutting out the bottom of the thing just so I could laser etch these tall boxes. But the inside walls are tapered, not vertical. The walls converge below to a rectangle shaped hole, with a steel drawer beneath, which cut pieces fall into. Don't have to pull the table to remove stuff, just pull out the drawer.
So last week SIX of these anodized housings come in. NOT looking forward to 6 of them. So I start thinking about cutting up the Triumph again. But the first thing I think of is cutting into the tapered sides, and that I'll need to cover the hole with something so the blower will work. But dummy me, one thing I've never done is take a simple tape measure to the catch drawer... Turns out the drawer opening is 19-1/4" x 12"-- and the largest box I've ever done is 18 x 10"... well DUH.. The hole is already larger than the table on my ULS laser! I swear, it doesn't look that big (but then a 51x32" laser does kinda dwarf it!
So yesterday, I took a deep breath, grabbed my trusty $6 HF air saw and started cutting. Had my BIL keep watch in case I started something on fire with the sparks. A half hour later, I now had a hole---
308846
where this now-scrap piece of steel was...
308847
-- I covered the cut edge with some wire covering. And what really worked out great, I left a 1/2" of lip at the bottom, so the drawer still works as normal, which takes care of plugging up the hole!
308848
The lower hole is larger than the upper hole even with the lip, so I lost no space. So now my dirt cheap laser is capable of accomodating parts 19-1/4" x 12" x up to 32" tall. NO MORE MANUAL ENGRAVING! And kudos to Triumph, the edges of the hole in the bottom is perfectly squared to the X and Y axis of the machine. I just put the part(s) in the upper-left corner of the hole, wedged it in place with some wood pieces, then all I had to do was level the top surface for focus.
This housing is 24" tall, still a long way from the floor.
308852
engraving came out nice--
308850308853
One issue to deal with, is the machine moving while rastering- since the part is resting on the ground, it doesn't move the same as the machine! The fix is to slow down the rastering a bit. But still have to be careful on short words, as it rasters fast and causes shake. The fix was to copy the same text 2" away- in this case "GND" was the issue, so I copied it of into the air space left of the box. If there's no air space, placing a metal plate where the dummy engraving would go works. (just don't forget!)
Setup time to do this box was about 3 minutes to level, another 3 minutes for text alignment, engraving time was around a minute. To pantograph this same box takes about 30 minutes. Most of these are more complicated.
my 'laser surgery' was well worth it, I should've done it LONG ago. I've been thinking about an "open" laser just for this reason, but this was a much cheaper alternative.
One of my ongoing engraving jobs involves engraving aluminum boxes, cases and housings. Most must be rotary tool engraved, due to several reasons, such as the aluminum and engraving requires painting, but mostly because of their size. Many of these items are black anodized, but are typically too large (tall) to fit in most typical lasers. I have a NH 3400 cylinder engraver, and it's vertically adjustable clamp allows me to rotary engrave items up to about 16" tall. This works well for one of my steady customers. But I have one customer who custom builds aluminum aircraft component housings, which are black anodized but rather large, typcally 24" to 28" long x varying H&W's, the largest is usally 18" x 10". My job is to engrave the top of the LONG side. How I've been doing these for the past 15 or so years is with an old New Hermes IRX-IV manual pantograph, which is clamped to an old school desk, which has a large aluminum plate screwed to the back, which serves as the surface to rest the housings against. The housings are held in place against the desk with a ratchet strap that goes completely around the desk. It works okay. But the engraving is a slow and tedious process, involving several master moves and usually one housing move due to the limited engraving area of the pantograph. Engraving across the top of an 18" wide part requires an engraving master at least twice that long (at 2:1 ratio), the machine doesn't have that much 'reach'. So I just fit each "text unit" at short intervals, and move the master to line up each unit. I eventually run out of pantograph travel, then have to move the part. This text-shifting process is also necessary vertically as well as horizontally...
So, whenever these parts come in, I cringe... ;) Pure time-eating, white-knuckle, proprietary work.
If only I could laser engrave these things...
Enter my cheap Triumph laser, the one I bought without a movable table. It's paid for itself at least 3x over so far, and I have my work-arounds for the non-adjustable table. Since the day I got it I've thought about cutting out the bottom of the thing just so I could laser etch these tall boxes. But the inside walls are tapered, not vertical. The walls converge below to a rectangle shaped hole, with a steel drawer beneath, which cut pieces fall into. Don't have to pull the table to remove stuff, just pull out the drawer.
So last week SIX of these anodized housings come in. NOT looking forward to 6 of them. So I start thinking about cutting up the Triumph again. But the first thing I think of is cutting into the tapered sides, and that I'll need to cover the hole with something so the blower will work. But dummy me, one thing I've never done is take a simple tape measure to the catch drawer... Turns out the drawer opening is 19-1/4" x 12"-- and the largest box I've ever done is 18 x 10"... well DUH.. The hole is already larger than the table on my ULS laser! I swear, it doesn't look that big (but then a 51x32" laser does kinda dwarf it!
So yesterday, I took a deep breath, grabbed my trusty $6 HF air saw and started cutting. Had my BIL keep watch in case I started something on fire with the sparks. A half hour later, I now had a hole---
308846
where this now-scrap piece of steel was...
308847
-- I covered the cut edge with some wire covering. And what really worked out great, I left a 1/2" of lip at the bottom, so the drawer still works as normal, which takes care of plugging up the hole!
308848
The lower hole is larger than the upper hole even with the lip, so I lost no space. So now my dirt cheap laser is capable of accomodating parts 19-1/4" x 12" x up to 32" tall. NO MORE MANUAL ENGRAVING! And kudos to Triumph, the edges of the hole in the bottom is perfectly squared to the X and Y axis of the machine. I just put the part(s) in the upper-left corner of the hole, wedged it in place with some wood pieces, then all I had to do was level the top surface for focus.
This housing is 24" tall, still a long way from the floor.
308852
engraving came out nice--
308850308853
One issue to deal with, is the machine moving while rastering- since the part is resting on the ground, it doesn't move the same as the machine! The fix is to slow down the rastering a bit. But still have to be careful on short words, as it rasters fast and causes shake. The fix was to copy the same text 2" away- in this case "GND" was the issue, so I copied it of into the air space left of the box. If there's no air space, placing a metal plate where the dummy engraving would go works. (just don't forget!)
Setup time to do this box was about 3 minutes to level, another 3 minutes for text alignment, engraving time was around a minute. To pantograph this same box takes about 30 minutes. Most of these are more complicated.
my 'laser surgery' was well worth it, I should've done it LONG ago. I've been thinking about an "open" laser just for this reason, but this was a much cheaper alternative.