Making Progress

[btboone]

Here's a picture of my two pens side by side. They won't fit into the Image Dome, so I had to improvise. The middle ring gets glued to the base in such an orientation that the splines look to continue from one part to the other.

Next up is a total redesign. A bunch of little stuff. I'll add a lot more weight to the base to make sure it stays in place as the pen is removed. I'll try a slightly wider base and a large 1" diameter bronze insert. If that's still not heavy enough, I'll probably have to go with tungsten, which is a bit more than twice as heavy. Changing the curve of the base will affect the splines slightly, so they will need to be dialed in again. I'll look into adding some kind of funneling type of plastic sleeve at the bottom of the hole in the base before the pen gets to the o-ring. Every now and again, the pen can catch on the o-ring. The funnel should prevent that. I'll lighten the upper barrel by switching to a wider diameter thread. Doing this means that the lower barrel will also have to be remade so the threads fit. At least I have a good start, and redoing all 3 pieces shouldn't be as bad the second time around.

 

[woodscavenger]

All I can say is wow. You're to cool. I think I should have paid more attention in math class and gone into some engineering field instead of medicine. I can't wait to see your continued work. Hey, what did you do with those aluminum prototypes...?[]

 

[btboone]

I still have the aluminum ones. The splines and ends don't completely match up as they are tighened together. I essentially had to make one and see how "wrong" it was and compensate by that amount. Rather than trying to match the aluminum parts together, I tried to match the aluminum back to the titanium front part. Being that each pen has different threads, I needed to dial in the pack portion to a mark on the front part that corresponded to 0 degrees rotation when I cut the splines. I added a small dot in the land between the threads and the front barrel body. I screwed the parts together, and marked that same spot with a magic marker on the back part. I aligned that mark with zero rotation on the machine when I cut the splines in that part.

By seeing how much the aluminum back was off from the titanium front, I was able to nail the titanium back the first time I tried. The titanium is so tough to work with I decided to not risk it by trying both aluminum pieces together. I had the titanium front as the new "master" that I had to match the back to.

 

[scubaman]

I don't care what everybody else says - these pens really aren't bad! [][][]

Nice going. I must have missed the significance of the splines... are they little springs that keep the pen centered in the base?

If I had the second pen I ever made (probably a prototype slimline) I'd offer it up in trade for yours. Before you throw it out []

 

[JimGo]

Bruce, those are AMAZING! I can't wait to see the finished pens.

 

[btboone]

Rich, the splines orient the top and the bottom so that the splines line up when the pen is resting in the base. You pull the pen out of the base with a slight twist. It's really just a cool factor, make it different type of thing. The shape of the wood ring is somewhat like a funnel, so that keeps it centered on the matching contour on the front barrel.

Before throwing it out, I'll still probably try the wood spirals just to learn from them. It's hard to see, but I really screwed up the top of the pen. I'm going to go to larger internal drills to lighten some weight, and I tried to open up the upper hole with a larger drill. Well, duh! the drill walked because of the cut angle and just scooped out one side of the hole. I had to sand the tip down to keep it from being nasty and sharp. I was going to make a plug drill to make the wood plug in the end instead of turning it on the lathe like I did a few pics back. By doing that, I can bore in the side of some choice olivewood pieces where the grain is going across the part rather than in line with it as the lathe would cut it. I will then make a fixture for the lathe where I can mount the wood plug and turn an offcenter three dimensional hemispherical cut on the end. The lathe fixture then needs to become a laser fixture to lean the part over correctly to laser it perpendicular to the face. It's a lot of work for a 5/16" wood plug, but it will be pretty slick if I can pull it off. Needless to say, my plug drill and lathe fixture will have to wait until I make a new back barrel with the correct hole diameter. [xx(]

 

[PenWorks]

Sorry Bruce, I read nothing that you wrote, but had a blast looking at your pictures [] What a dynimite looking pen.

 

[btboone]

Anthony, I may have to lean on you or Rich (or both!) for your photography skills when the time comes.

My lathe was filled with super fine wood chips tonight. I don't push very hard on these thin parts. They reminded me of fall leaves. The colors were similar with the oranges and browns in thin leafy chips.

 

[scubaman]

Ah, only the spirals on the base are wood filled? I thought they all would be! I'm wondering how well these fingers will hold up. They are CA'ed down, are they? And even though they aren't angled the shape is such that they catch the spiral grooves in the lower body?

OK, I'm impressed. [8D][8D][8D] I mean <u><b>I'm impressed [8D][8D][8D]</b></u> (Is this really the biggest font available here?

I empathise with you on drilling into an angled surface... been there...

 

[btboone]

Rich, the outside parts of the pen, the upper barrel and base will both have wood. If done well, the wood should look like it continues from one part to the other. The lower barrel, the inside part toward the nib, has rounded bottom grooves with no wood. The spiral grooves there are just something fancy to grip onto. I do plan on CA gluing the whole middle ring including the splines right to the metal base. Hopefully they will be strong enough. I tried pulling hard on one of the prototypes and actually couldn't break the splines. The glue should add some backup support as well.

Yup, the shape is such that they catch the spiral grooves even though they aren't angled. That's where the new corner rounding/ trepanning tool came in. [] I'm impressed that you used your biggest font! []

 

[btboone]

I worked on the wood insert for the top of the pen last night. I decided to make a plug drill instead of turning the wood on the lathe for the plug because it would be easier to find a piece of wood with a nice grain that way. Of course, the size I needed was nowhere to be found in a commercially made plug drill, so I had to make my own. It worked OK, but the flutes clog up pretty easily with the oily olivewood, so I needed to stop the drill and clean out the flutes a lot. I made a lathe fixture where I can put two wood plugs in it, and it will bottom out on my chuck. I then turn the off axis spherical cut on the wood parts.

 

[btboone]

I used the lathe fixture in a new aluminum fixture to be used in the laser. The square corner of the block with the 0's stamped in it goes into the corner of measuring rulers on the laser table. The fixture tilts the holder of the wood plugs such that the face of the plugs is perpendicular to the laser beam. I just bought a finer focus lens for the laser to make an smaller beam. This one should give around .0015" resolution, whereas my other lens made a spot around .007". I lasered my logo "B" into the wood then rotated the fixture so that the next wood piece could be lasered.

 

[btboone]

Here's the result of the lasered plugs. Keep in mind that this is still the prototype pen, and the drilled hole at the end of this one got all messed up when I tried to drill it larger. I was able to hand fit the wood to fit OK on this one, but hopefully it should look a lot better on ones where the hole is made to the correct size beforehand. I'm still on the fence as whether to darken the engraving for more contrast or leave it raw and subtle. I like the fine textured hatching in the logo, so if I color it, it would have to be done with something very watery to preserve that look. I can experiment with dyes or a magic marker and see how it looks.

I'm in the midst of remaking all the tubes with larger bores to cut down on the weight. I'm also changing over the machining to do it on my big machining center rather than my tabletop machine. This allows the use of coolant, so I can run the parts faster. I had an issue on the small machine where the Z axis (up and down axis) was losing counts due to friction, so the slot accuracy was affected. It would ruin the part that took several hours to get to that point. My big machine was not set up to do long thin rotary axis parts, so I needed to change it over and take off a large perminently mounted pallet fixture to make room for a tailstock. I think the change will be worth the effort for productivity and repeatability for production.

The pen constantly amazes me at how much work it is. Hopefully all the work I'm doing now will make it easier for more to come.

 

[ashaw]

Bruce

Very Nice....Nooo Really Nice[8D]. You are taken pen making to the next level. I like what you have done.

Alan

 

[Randy_]

Bruce: On the final pen, will the wooden plugs be flush with the end of the pen or will they be inset slightly as shown in the picture??

 

[btboone]

Hi Randy, I planned on having the plug slightly inset. I have the side view on CAD way back on page 1 of this thread. As I mentioned, I think it will look better when the plug doesn't have to be refit for the hole. What's your opinion on that? Do you think it might look better flush?

I'm not sure why the plug looks so skewed in the side view shot; it is very slightly cocked to one side, but not nearly as much as the side view shot seems to show. Must be a trick of parallax and photography. It actually looks pretty straight in person.

 

[wdcav1952]

Hey, I thought this was a pen turning forum!! [][] Damn Bruce, like others have said, I don't understand a thing you are saying, but I like looking at the pictures. For Anthony and me, please keep posting lots of pictures.[8D]

 

[woodscavenger]

Make it flush. I think since the other wood inserts are flush it will look nicer.

 

[btboone]

I just made my final end plug tonight and darkened the engrave with dye. I tried doing the whole thing coated in CA, filling the engraved area, which actually looked good. It looks almost like a cabochon. I'll check both height positions when I finish cutting the titanium barrels on the machining center. I'm waiting on a special collet to hold the parts in my 4th axis.

I also laser fired ceramic engraving the bottom of the bronze base piece. I made a simple L shaped fixture to locate it in the laser. I applied some lacquer to the part when it was done. It looks good. The tighter focus on the laser makes a difference.

 

[rtjw]

very nicely done. I think it would look nice flush, but heck, I aint no where near your work.

 

[Randy_]

Bruce: I was kinda leaning towards flush; but the photos can be very deceptive. I'm sure you have a better feel for the best option since you have the pen in hand.

 

[btboone]

Well, Mr. Murphy made a visit to the shop last night. I was able to work on the pen all day yesterday, and I was machining the last spiral of the last part (the long barrel), and broke a tool. No big deal. Just replace it and continue, right? Wrong. The new tool immediately went to the land between the spirals and dug in there. It seems that I lost rotary feedback sometime during machining my part. The rotary axis is totally out of control, and machine doesn't know where it is. I stayed up half the night checking wires and the mechanical connector between the servo drive and the encoder and anything else I could think of. No go.

I need to remake that part from scratch, which takes several hours and rewrite the new code back for the little machine, so it can do the spirals again. The cost of getting someone out to fix the machine will negate any profit left from the pen, assuming it sells at all. To add insult to injury, I got 2 rings last night that need the rotary axis to complete them. [B)]

Mr. Murphy, go home!

 

[JimGo]

Sorry Bruce!

 

[btboone]

<br />

I worked half the night last night on the machine and finally get it working properly. I completed the back barrel. I had a tool break at the same location today! I checked the code and everything looks good. I think the tool just wears down and gives out at that spot. I was able to complete it with a sigh of relief. I just need to do the wood inlay and assemble it. Here are all the parts so far.

I still need to make a special screwdriver to mate with the brass nut to lock in the nib at the correct angle. These will be sent with the pen. I might do them in either brass or a stainless drill rod. I also am getting in some really nice sample boxes from Rocket Box. The one I have in mind has burled wood on the outside and has suede on the inside. It's around 7.5 x 7.5" x 1.75" and made for a necklace. It looks awesome. I'll see if I can laser out a custom insert to nest the parts in that.

 

[rtjw]

Looks like it is going really good. Cant wait to see the final product.

 

[JimGo]

Wow, that's going to be a beauty! So, should we all get in line to be testers for you? [] If so, the line forms behind me!

 

[btboone]

Thanks guys. Hopefully, I'll complete it tonight. I realized this morning that I'll need to make a special mandrel to hold the back barrel for remachining after the wood is glued in. I did it all by hand last time. It will have threads for the barrel to screw into and also have a long mandrel to hold the part and get supported by the tailstock.

It looks like I will do the wood plug buldging up from flush on the top angle. I was concerned about having to get the seam perfect, then I realized that I could glue it in with CA, overflow the glue up top, and just sand it back to the metal surface. Since the whole part has a curved blob of CA up top now, I should be able to blend it in nicely with micromesh.