Gambled and Lost!

[btboone]

I tried to do a polyester pen with two different colored resins in an interlocking pattern. I wasn't thrilled with the results. I had tried the same technique on the Puzzle pen I had done and never got the resin to cure. That was done in wintertime, so I wondered if the temperature had a lot to do with that. I tried it again and got the resin to cure, but it still didn't fill the alternate areas like I would like. I had to laser the pattern pretty deep in order to fill above it, and the heat distorted the cut line slightly. I think that the residue left over from lasering must play a part in the resin not curing right in the dividing point.

I am still toying with the idea of doing it in two colored woods, but the laser beam gets wider as the wood gets thicker. I would need to compensate for the beam width and match the draft angles to make that work. I think I would also lose a lot of detail that way. Another thing to try is simply engraving a shallow distance and coloring the lasered stock in a contrasting color. The detail is much crisper that way. The top of the pen will have rotating dice to complete the theme.

 

[PenWorks]

I know the feeling [] [V] []

 

[ctEaglesc]

WHy not try with a scroll saw?

 

[btboone]

It would be really delicate with a scroll saw. The stalks that connect the different parts are only around .030" across. It could probably be done with the right equipment. I don't have one though. Another option with wood might be to burn out most of the material and only make a finish pass that touches the final parts. The heat of the laser would stay away from the finished parts and might make a better finished surface that way.

 

[woodscavenger]

Bruce your awesome to even think of that type of design. The closest thing I will ever have to a laser is a laser pointer. []

 

[btboone]

Hmm... another really strange option that should definitely work is to laser cut a bunch of very thin wood strips and glue them all together. The laser is awesomely sharp (about .007" kerf) when the part thickness is kept to around 1/16". I already compensated the lines of the designs for half the beam kerf, so I would just need to do the opposite part in a different color wood (or plastic). The parts should fit together pretty nicely then. The thin parts could all be glued up in a stack then the finish block turned. The only downside would be that the laminated grain might show. I have a stack of Popsicle sticks that I could experiment on. The problem is that all the experimenting takes TIME! Doh!

 

[wdcav1952]

Thanks Bruce, now my band saw is too depressed to cut any more blanks! [8D][][8D]

 

[btboone]

Don't be depressed William; I'm about to send all my casting supplies to Anthony or Alice to get lessons on how it's done! I haven't yet done any polyester that I'm real proud of. I've also tried at least 10 iterations of a project involving CA, rattlesnake skin, and a titanium ring. I have yet to get good results.

Maybe I should stick to titanium!

 

[alamocdc]

Bruce, Eagle beat me to it. The first thing I thought of was a scroll saw w/an omni-directional blade.

 

[btboone]

I think the ultimate way to make the pen would be to have a solid inner core of wood like a normal pen, and thin tubes of wood on the outside. The thin tubes would be cut by the laser in the interlocking pattern such that the pen would have 4 alternating colored quadrants; red, black, red, and black. They might be around .050" thick. The quadrants would have simple line contact opposite their interlocking sides. This would allow the parts to go together without locking problems. The parts would simply be glued to the inner core. It would be a lot of work making all the thin tubes of wood, along with their mandrels for laser cutting, but the resolution of the design would be unmatched by making it that way.

 

[ctEaglesc]

Actually my remark about the scroll saw was made partly in jest.Though I am sure using the principles of marketry a similar effect could be acieved by a good craftsman and a scroll saw a lot better than my cheapie.
Though I have no interest in casting my own plastic blanks I am wondering if I am missing something.
Wouldn't the simplest meathod to accomplish this be to cut one cast blank with one color as a a "master" and then recast the same blank with a contrasting color on the the half?
Wouldn't the second casting bond to the first and be a perfect match?
It sounds like the simplest method to me but as I said I have no interest in plastics.( other than CA[])

 

[pastorbill1952]

My ignorance in machinery etc, is probably about to show its ugly head again. What about the dovetail jig that uses all types of shapes? Someone did a regular dovetail blank from contrasting woods that was really nice. Also what about a rubber mold like they use to make plaster castings for molding in old houses? Make a negative mold for each piece. And another thought, can you laser etch the line enough to fill with inlace or other filler?

 

[Paul in OKC]

[quote I have a stack of Popsicle sticks that I could experiment on. [/quote]

I'd be glad to help in your research by taking care of the Popsicles to keep you in a supply of sticks[]

 

[btboone]

Cteaglesc and Pastorbill, the laser did fairly good job on cutting the one side. I did it very similar to the way you described, but the laser runs into trouble if it gets far enough down to reflect the beam off the brass tube. You get reflections of the beam cutting through the part in places you don't want it. The extra heat also remelts or ruins the plastic. For this reason, I didn't go through, but rather just cut the design and got rid of the extra material in between with a hatch pattern. I used low power and repeated the burn several times to get the depth I wanted. I went back and cast another color over the first and turned them both down. I just don't seem to ever get great results when trying to cast like that. It does look a lot better in person than the picture allows, but not the quality I had in mind. I imagine it would look a lot better if it were sent to someone more accomplished in casting. I think I could use tinted CA and get better results than I did with the second color of polyester.

 

[ctEaglesc]

Is it mandatory the blank be drilled and tubed?
No way to set it up"between centers" and "locked" for laser cutting?
Just wondering.
(BTW you gavce me an idea, thanks. results to follow)[]

 

[btboone]

The laser shouldn't need a mandrel, although that's the way I have it set up now. Still, the spreading of the beam burns quite a bit more wood when the focus isn't tight. Sometimes you will get an actual flame if the beam is too spread out. That does make a huge difference in the look of the part.

There are lots of cool possibilities with a scroll saw and different colored woods and interlocking blank parts. Looking forward to seeing what you come up with.