Making Progress

[btboone]

I made a prototype of the base of the pen I've been working on. I had to prove out the difficult programs needed to cut the spiraled grooves in what will be a titanium pen. The grooves are filled with wood. These are not just veneers, but they are relatively thick, and are laser cut in spiral forms to match the grooves so the grain will be continuous. The prototype has cherry and I intend to try olivewood for the real pen. I was originally going to make the entire pen shape from wood and then laser cut the spirals from that shape. It would work, but there were going to be manufacturing difficulties of making such a thin trumpet bell shape on the lathe. For one, the hydraulic tailstock of my lathe would crush the part. For another, this meant having an 8" long x 1 1/4" diameter wood piece that everything would be taken from. It is expensive and wasteful for the highly figured wood that I'll be looking for. I was able to get all the spirals and the spirals for the upper half of the pen (not made yet) from a single 3/4" x 3/4" block 3 1/4" long. The spirals all nest together so that the grain will match on the upper and lower parts. The base ring is now cocobolo, but again will be olivewood. There will be an upper ring as well. The pen will have the spiraled wood on the back portion and the front portion will have spiraled grooves. The upper wood ring will have internal splines that fit the grooves so that they act as threads. On the inside of the base is an O-ring that seals off the nib.

My progress has been slow because I've been unusually busy with the rings. Last month was a record month. The upper pen part has its share of challenges as well. One is that the nib end and the back end both have an angled cut. It was a challenge to figure out how to orient the darn things. Another was to be sure that when the pen is set down in the base that the grooves all line up. There's still fixturing and manufacturing stuff to figure out before I can make that part.

Just wanted to show that I am in fact working on pens when I can!

 

[arjudy]

That surely will make an interesting pen.

 

[Thumbs]

Bruce, I read this twice and I'm pretty sure you know what you're doing. That's good, because I have no idea! LOL![]
As long as you're having fun that's most of what counts!.....[] Good Luck with your project and its progress![]

 

[rtjw]

I agree with Thumbs. I have no idea what ytou just said. But I basically put it into laymans terms. Your going to put us all to shame again.

 

[btboone]

Sorry. A little background first. Here's what I'm working on. It's a fountain pen where the base stays on a desk. The big concept was to have mirror finish titanium with a nice wood in spirals going up the sides. It's a very challenging project to put it mildly. It took several hours of hand writing 3 dimensional code to work out the spirals. The code for the laser had to compensate for the beam width and the flaring of the base. It also had to nest with the other sprials for the other pen part. The code for the endmilled spirals had to compensate for the tool width on the flared part as the groove changed width and diameter and rotation. I wasn't sure if they would work or not. As rough as the plastic part looks, (in part to hand drilling the deep 1/2" hole), I was very pleased that the spirals seemed to work. It took about 8 different programs and several fixtures and lots of hours to get the part to this point. The other pen half, where the spirals don't change diameter much should be cake compared to this part. This was a tough one.

 

[knottyharry]

Hi Bruce,
This is very interesting. And I will be awaiting the final project.
Very nice work.
Harry

 

[btboone]

Thanks Harry. The biggest thing is to figure out how to hold and turn the parts. The base has a 1/2" hole that goes through. Since the chuck needs to hold onto a stalk, the piece is about 4" long to start. Drilling that deep in titanium is drill suicide, so I have to drill halfway into it from the backside and half from the front. Even that is too deep to get coolant to the tip, so I have to drill about an inch deep and make a funnel shape with the boring bar to get coolant to the drill as it goes deeper. It's the little things like those that make it difficult. It all needs to really be thought through beforehand. Because it's a CNC lathe, I generally get a good part the first time if I've done my homework on the setup, fixtures, and programming. The program usually takes final tweaks, and that's the purpose of doing the prototype in acrylic. I can see the internals and clearances inside the part as I go.

 

[chigdon]

That will be amazing. I can't wait to see it!

 

[woodscavenger]

Hey, that looks amazing. How about throwing a quarter or something in the photo for scale? First glance it looks huge. BTW, I wish I were smart enough to follow your description. I'll have to wait and see. How is your FP twist holding up?

 

[btboone]

The new pen will be slightly larger than the twist pen, but still not too bulky. The overall length of the pen without the base is 6.09" x .64" diameter. With the base, it's 6.28" tall and 1.20" diameter at the base. For comparison, the twist pen is 5.61" long with the nib extended as shown and .58" diameter.

This one was designed to sit on a desk, so I wanted a bit more of a commanding presence. The wood also worked better if there was a little more thickness to the pen. The main issues of the twist pen are the fact that it is stored upright and the designed (but yet to be built) trapdoor might leak air and cause the pen to not write. This would be a show stopper. As a test, I tried to see how long it would write without a trapdoor, and it was only a day or two. In such a high end pen, I wanted to skew the odds better in favor of always working.

In starting with a clean slate, I decided to do away with the trap door and increased potential for the pen to not work. I also got rid of the clip that many people were not crazy about. It was extremely difficult to make and never would work as well as a clip that was stamped. This left the gripping portion of the pen unobstructed. I still wanted to get rid of threads that most pens have and so I kept the grooved slots that were on the other pen. I like the feel of the slots in my hand. They also lend some much needed cool factor. I reversed the direction of the grooves because they will act as high helix threads to orient the pen when it is seated in the base. It just feels more natural to have a right hand thread than a left hand thread to slip it into and out of the base. The seal inside the base is actually not a normal O-ring (MSC carries all the usual sizes EXCEPT for the size I designed for!) but a metal washer with an internal rubber flange. It is actually a better solution because unlike an O-ring, it can't squirm out of position. It is trapped in by a cylinder of bronze. The bronze is cheap and heavier than the titanium, so I used it to help get the center of gravity as low as possible.

The picture shows the wood spirals. Some are still attached on the wood tube. As you can see, there's not much room between the spirals! The spirals still needed some careful persuasion to seat into the slots of the flared base, but I soaked them in oil to help soften them up. When they were glued in, they stuck out of the base, and I was able to put the part back in the lathe and kiss them back to flush. They were finished with CA and sanding from there.

 

[scubaman]

So you decided to cut the spirals out of a cylinder rather than a trumpet? Or is the barrel you show for the pen body spirals?

I find the design of the base extremely attaractive!

 

[btboone]

Hi Rich. Yes, I tried to see if I could get both the long upper pen body spirals and the shorter pen base spirals out of a smaller diameter. The parts actually nest with one another with no room left over. Since it will be olivewood, it would save a lot on the wood cost. I wasn't sure if I could do it or not since the shape was not the same. It took a lot of trial cuts to get the wood to fit. I had to keep tweaking the shape. The other issue at hand with cutting them from the trumpet bell shape was that I would need to use a long and slender boring bar to get inside and the part would be fragile. It would also need a special fixture for the laser. Another technique I looked into has the wood drilled at different diameters on the inside. You can see the cut view of that in the CAD drawing. The issue with that is the wood spirals change thickness, so I was afraid that I would have to use more laser power and mess up the thinner sections.

The wood would definitely fit better in the slots if it came from a trumpet bell shape, but it would add a lot of time, complexity, and cost to make it that way. As you can see on the CAD drawing, I toyed with the idea of making all the spirals and attached upper ring from one wickedly cut piece. It would have been a technical wonder, but didn't look to flow as well as the separate spiral pieces.

The base looks better in person than the photo allows. You can see all the internal glue spots and drill marks that won't be visible on the real part. The pen part will flow seamlessly from the base when it's in position, so I'm looking forward to trying that. Because the upper part is pretty thin, I might go ahead and try it in titanium the first time out. I need to make a tap for the nib and make a brass sleeve that it screws into so that it can be reoriented to match the angled cut at the front of the pen. The back part of the pen will then be made with an angled cut that needs to match the front part. Doh! [:0]

 

[woodscavenger]

Thunk!! That was me falling off of my chair.

 

[Paul in OKC]

Awesome stuff, Bruce. If I had your toys .......

 

[PenWorks]

Nice.....................[]
I like the metal/wood combo []
Should be a WINNER !

 

[nilsatcraft]

Great to see some more innovative and one of a kind work, Bruce. It's gonna be an incredible pen. Thanks for sharing!

 

[btboone]

Thanks guys. I'm using one of Anthony's small gold nibs. It should look very nice in the pen. Paul, I could have used one of your vises the other day; I drilled my first blank for the wood tube and had the wood slightly angled in my milling vise. I got a little thin on one side.[:I] I knew that the shorter spirals were surely not going to work properly the first time. I had to add something like 3/8" to them to get the proper length for the fluted base. It took several more tries, so I got more practice at drilling the blanks.

Nils, hopefully it won't be one of a kind. If it works well, I would hope to produce a lot more just like it! []

 

[Doghouse]

cannot wait to see the final result! OUTSTANDING so far!

 

[btboone]

Unfortunately, I need to get back into ring making mode. It may be around Thursday night before I get on top of rings if it's like it has been for the last few weeks. Slow progress, but progress none the less. I can keep doing updates whenever I have something to show if people are interested.

 

[MDWine]

Yep! We're interested!!

 

[btboone]

I rehashed the way to orient and hold in the nib last night. I came up with a much better solution than what I had in mind before. I'll made a small cylinder of brass that the nib screws into. In the front body of the pen the hole chokes down in size so the nib can't slip any further from the front. This new brass piece serves as a nut to hold it in. I'll make some screwdriver slots in it and make a special screwdriver tool that can tighten it down from the back while the nib is held in proper orientation from the front. This will allow for fine rotational orientation the splines or morse taper or other techniques I was considering had issues with and is a lot easier to implement. I'll try to make that tonight if I can get ahead of the ring orders.

 

[btboone]

<br />
Here is the brass nut that the nib assembly screws into. It's a tiny little thing. I had to make the M6.5 x .7 tap for the threads. The part is extremely thin so that the ink cartridge can plug into the nib without crashing into the brass walls near the screwdriver slots. I'll make a cylindrical screwdriver tool that can go in from the back side of the pen that's exactly the diameter of the tiny screwdriver slots. This will allow the nib to be rotationally oriented to match the angled cut on the front of the pen.

 

[rtjw]

Looks nice. Cant wait to see the finished pen. Is it sold yet are being kept?

 

[btboone]

I don't have a buyer for it as of yet. I was wondering about taking Anthony's route and placing an ad in a mazazine or trying to get an article on it and making a limited batch of them. Once I finally work out the manufacturing details, making other ones won't be as tough. I just need to be sure it works well and looks the way I hope it will.

It's putting the cart before the horse a little, but I would be interested in hearing people's opinion on pricing and marketing for such a pen. Just sell direct? Go through dealers? At what cost? Number of pens in a limited edition? What about if I add a rollerball, how does that affect a limited edition? How is it presented to the customer? One train of thought says just wrap it in bubble wrap to show that it's truly a hand made piece; another says to buy as fancy a box as money can buy. There's lots of stuff I don't yet know about this market.

 

[rtjw]

I would put it in a magazine. As great as it looks it would sell.

I know anthony does limited editions. I would email him about that. I wouldnt say more than 100.

I wouldnt put it in anything but I nice presentation box.

As far as pricing, I will start the bid at []$50.00[]

 

[ashaw]

Bruce
If you look at mag like Pen World you are beginning to enter the $1,000.00 price range.[] You need to come up with a box as unique at the pen. I would try to get into the mag route. I know it is difficult not impossible. The big manufacture have the spot light in that type of media. Also talk to Fountain Pen Hospital in NY.

Alan

 

[JimGo]

Bruce,
I agree...I think a limited edition is the way to go. The price point for it will determine how many to make, IMHO. If you're looking at $1,000 a piece, I don't think I'd go with more than 100. If you're in the $500-750 range, then you might be able to bump that up some (maybe 200-250 @ $500). I'm <s>cheap</s> frugal, but if I had the cash on hand, I'd be willing to pay at least $250 for that pen. I'm not suggesting you actually sell them at $250 each; rather, I'm suggesting that as an absolute low-end for the pens. As Johnny pointed out, Anthony has experience with some limited edition pens that were made by a big pen manufacturer. He can probably give you an idea as to what the market is like at different price points.

Good luck!

 

[btboone]

Pen World is exactly who I had in mind. Obviously, the quality and function will have to be dead nuts for that to happen. I'll need to figure out the time it takes to make them, but I was thinking possibly in the $1500 range. I've probably spent about 80 hours on the design and few parts I've done so far. I assume dealers would pay around 65%, or $975. I guess the lot size has a lot to do with how many would sell. I would think a definite upper limit of 250, but I don't really know the lower limit. It would be nice to have a sliding lot scale depending on orders. [] I'll try to see what Grayson Tighe is doing and copy similar numbers. I can laser engrave the serial numbers on the bottom of the base. I still wonder if it's a good thing or bad thing to venture away from the expensive boxes of the big guys. I'll need to think about what's possible there. Maybe leather and fur lined boxes?[] I suppose there are specialists for that.

 

[rtjw]

So what are you saying bruce. I cant get that pen for $50.00!

 

[btboone]

I didn't say that Johnny. The fur lined box is what adds the cost.[)]

 

[CPDesigns]

Are you kidding? For that pen, anything less than a diamond-lined titanium bank vault is doing it a disservice. Seriously, I think you're definitly in the ballpark of $1500 if you're satisfied that the details and mechanics are spot on. I'll be happy to give a prototype a test run for you. I work in a very busy ICU and I write all day long.[] A week in this place is at least a year anywhere else...[]

 

[btboone]

We'll see if the details are spot on with some testing. They should be close. I probably will get different people to check it out and give me their feedback. I've been testing the O-ring and base with a Sharpie pen for the last week. It seems to work well with no hint of drying out. The only problem there is that the plastic base is so light that I sometimes lift it when getting the pen out. Hopefully the titanium with the bronze insert will be heavy enough. I can use tungsten if I have to, which is 4X heavier than titanium, but it is very expensive. (~ $800 for a foot of it!) [:0]

The vault idea makes me think of Oakley's aluminum case for glasses. [8D]

One detail I'm concerned about is that the hole in the base has exposed metal and the front part of the pen is polished titanium, so it may scratch the pen when it is put in and taken out of the base repeatedly. The upper wood ring will help to center the pen, but may not prevent scratching. Space is extremely tight with the wood inlays cutting into the base, so there's not enough room for velvet or a plastic sleeve as I have it now. I'll need to see if that's an issue or not. Hmm.. I wonder if some CA and flock material would work.[?]

 

[btboone]

<br />

I have the 3 main parts turned in titanium. I literally worked all night long last night and all day today to get them to this point. I've run into a couple issues. Tapping the main body with an 11mm hand tap proved extremely difficult. I didn't do it on the lathe because it's not a high performance tap and I figured it would just snap right off. I can only get a few threads into the body. Titanium is darned near impossible to tap by hand. I can shorten the barrel threads a little bit to compensate. Being titanium, they'll still be plenty strong. My other issue is that my steel mandrel to mount the base onto the 4th axis machine has a .500" diameter. The hole drilled was also .500". It was a clean enough bore that I could press the part onto the mandrel for machining the spirals. A .501" ream should make it easier. The same story goes for the hole for the nib. It's so tight that I could use a ream that's a couple thousandths of an inch larger than the drill I have. I proofed both parts in aluminum first. I made a couple tweaks to ease up on the slot depth on the front barrel, but other than that, they looked to work well. I have something like 20 programs now.

Tonight I need to write the code for machining the spirals on the long back side. It's every bit as much of a chore as the flared base ones were. The part changes diameter while the spirals go around and get wider at the same time. I use a calculator and a CAD screen to calcluate all the hundreds of coordinates by hand. Did I mention that I also need to orient them to match the lower barrel!? Doh! I'm getting a little punchy.[|)] I need to go ahead and write the code before the ring orders flood again tomorrow night.

I still need to hash out the middle wood ring that has the insides splined. It will be tough to make because as it's designed, it needs turning from both sides as well as lasering for the splines. I won't be able to regrip on the wood for turning the backside without destroying it. I had a new idea that I'll persue for that after I write the code for the long barrel.

 

[woodscavenger]

Bruce you are awesome. Keep it up. Need a Jolt cola?

 

[btboone]

I finally got the coordinates done. It took a while to remember how I did the calculations for the base spirals. In the hundreds calculated I only missed two. I was able to run a toolpath simulation on the computer and two of the lines looked out of place. I'll run the part tomorrow. I need sleep!

Yesterday, I actually did drink a Coke around 7:00 pm because I knew I'd hack on it all night. I went to bed after the sun started coming up. [|)]

 

[rtjw]

Looking really good.

 

[btboone]

I got the spirals cut on the back barrel. I had to make the first cut on the aluminum prototype and see how the spirals lined up and adjusted the code accordingly. The spirals and the two ends match up well. What looks to be an angular difference in the picture is just from parallax from the tight shot. I turned the middle wood ring and the small plug that goes in the end from the remaining part of the pen blank that the spirals come from. I do both in one program. I just clamp the hydraulic chuck on the square wood, crushing it, and turn what sticks out of the chuck. I chose the nice looking turned blank in the pic as the final attempt wood. It looked best of the ones I did.

I needed a blind turned slot on the back face of the ring to attach it to the stepped shelf on the base. I made the trepanning tool that's shown. It didn't work well with flat teeth so I sharpened them like a saw blade. It worked fine. I spun the tool in the manual lathe and held the wood ring by hand. I realized after I made it that I can round the back of the splines by hand with a special cutter that works just like the trepanning tool. This was my original design intent. The rounded splines will fit better into the slots of the front barrel that way. The first ones were a bit tight. This was caused by the difference in the straight laser cut splines and the helix angle of the splined grooves on the pen body. This is a project for next week.

Another thing occured to me after it was made; it is heavier than my other pen is. I realized that I can probably take out some more metal on the inside if I switched to a larger diameter thread. I may be able to use a 1/2-20 tpi thread, and some high performance taps are available that should be able to withstand the lathe torque. This will save around an hour or two of time and make better threads and make the whole pen lighter. The back half of the pen can have a slightly larger drill as well for more weight savings.

I think I'll keep finishing this "beater" pen to see what else I can learn before tackling the "real" pen. Every time I run it, I tweak the programs to be faster and better.

 

[btboone]

<br />

Here's the back of the middle ring with the trepanned slot to fit the boss on the pen base. The inside also has a radius. Both were done with the new tool I made.

 

[btboone]

Here's the ring with lasered splines in them. Getting it to line up with the laser is tough, and some good fixturing will come in handy. Notice the splines extend downward a little from the upper ledge.

 

[btboone]

Here's the base with the middle ring in place. This prototype was made in cherry. After putting it in place, I kinda liked the contrast in woods between the bottom and middle rings. Hmm... I might keep it olivewood because there will be a plug in the upper barrel that will get laser engraved, so it will show up better on the lighter olivewood.

It took several tries to get the ring to work. They kept getting crushed as they came off the lathe, so I slowed the cutoff speed way down. I also added a stopping point where I add CA to the part then turn it back to flush. It fills all the pores and strengthens the wood. I still need to figure out how to best get the "laser tar" off of it and final sand the delicate splines. Maybe sandpaper on a toothpick or something. I'd like to get better consistancy there.