Model Engine Maker

Engines => From Kits/Castings => Topic started by: maury on August 22, 2017, 03:50:27 PM

Title: The Dickson!
Post by: maury on August 22, 2017, 03:50:27 PM
Well folks, with the home improvements mostly behind me now it's time to get back into the shop. On my
trip to NAMES this spring I had the opportunity to pay a visit to Dennis Howe of former Historic Model
Design. He is and had been for about a year working on a new scale model. The Dickson! It's a triple
expansion marine engine fitted for stationary use with 2 large dynamos.During our visit it we decided
I would join the project as well, I will be bringing design and casting experience to the project.A
third guy, John Ugo is also in the group, he is designing the electrics for the dynamos.

This is a really magnificent engine, It uses Joys valve gear, has steam valving to allow the engine
to operate as a triple expansion, or 1,2,or 3 cylinder mode and also some combinations of cylinders.
The engine was used in the Henry Ford Plant to operate electric motors for the assembly lines. As I
understand there were 7 of these engines in the plant. The one in the includes pics is located in the
Henry Ford Museum in Detroit. Fortunately, Dennis has been able to dig up some of the original drawings.

That id Dennis standing by the Dickson.

maury
Title: Re: The Dickson!
Post by: b.lindsey on August 22, 2017, 04:41:29 PM
What a fabulous project Maury. I am sure your expertise will be most helpful to the group as well.

Bill
Title: Re: The Dickson!
Post by: jeff l on August 22, 2017, 04:50:32 PM
Nice project for sure , but the engine was never in a Ford plant . It was owned buy the Edison Illuminating Company and was in service at the Duane Street station in New York it was in service from 1891-1928 after which it was donated to the Edison Institute which is now the Henry Ford . Jeff
Title: Re: The Dickson!
Post by: Ye-Ole Steam Dude on August 22, 2017, 05:08:19 PM

This is going to be a wonderful project to follow. Thanks for sharing.

Thomas
Title: Re: The Dickson!
Post by: maury on August 22, 2017, 10:25:22 PM
Thanks for the encouraging words guys, and JeffI, thanks for the historical correction. Guess I misunderstood or was mis-informed. There is a lot of history associated with this engine, for example, it was during that time that the AC/DC wars were going on. Seems AC won out, obsoleting this electrical design.

A few more pics, the piping is what I'm currently working on.
maury
Title: Re: The Dickson!
Post by: Johnmcc69 on August 23, 2017, 01:14:53 AM
Now that is cool! Looking forward to seeing it come to life!

 John
Title: Re: The Dickson!
Post by: Dave Otto on August 23, 2017, 02:04:00 AM
Fun project Maury!
And right up your ally; looking forward to seeing the updates on this project.


Dave
Title: Re: The Dickson!
Post by: steamer on August 23, 2017, 03:40:17 AM
Oh that's nice!!!

Dave
Title: Re: The Dickson!
Post by: Jasonb on August 23, 2017, 09:48:57 AM
That should keep you quiet this winter and maybe a few more too.

What sort of scale are you going for? It's a big engine so you will have to strike a good balance between a practical size to machine but one that does not make the smaller details a watch makers project or simplify things by leaving some items out.
Title: Re: The Dickson!
Post by: Roger B on August 23, 2017, 08:24:34 PM
That is a magnificent machine  :ThumbsUp:  :ThumbsUp: I look forward to the model  :wine1:
Title: Re: The Dickson!
Post by: maury on August 25, 2017, 02:11:06 PM
Guys, thanks again for the kind words.

Dennis has chosen a scale of 1/20. This will make some of the detail difficult. but at that scale the model will end up being close to 100#. That's big enough. There is no problem with out machines, we have machine capacity for large models.

The piping and valve models are coming along, the precarious thing is getting them to fit with the cylinders. Dennis is doing the cylinders. Also, there is no give in the piping, as it's all flanged together.


maury
Title: Re: The Dickson!
Post by: Jasonb on August 25, 2017, 02:53:01 PM
Would you not make the pihework up working out from the cylinder soldering the flanges, pipe and bends as you go in much the same way the original pipework was welded up. You could have a dummy tooling plate to represent the cylinders and a dummy valve body.

Is that just the chosen colour on the model or are you casting/machining the lagging integral to the pipework and just painting it white?
Title: Re: The Dickson!
Post by: Dennis on August 25, 2017, 03:45:43 PM
Hi Maury,  Thank you for starting this thread. This is my first experience in a group build with everyone building the same engine and I am finding it quite enjoyable.

Here is some more history on the Dickson:

This engine was the first time a triple expansion engine was direct connected to two dynamos and represents a big step forward in mass producing electricity for commercial and home use.  The engine was built by the Dickson Manufacturing co. in Scranton PA and the two DC dynamos were built by the Edison Electro co. in Schenectady NY.  The engine and dynamos were installed in Edison's Duane Street generating station Dec 15, 1891.

The three cylinder bores are 18, 27 and 40 inch with a 30 inch stroke developing 650 HP.  the dynamo output is 120 V DC from each dynamo.  Power was delivered by way of a three wire system with each dynamo feeding one of the wires and a neutral wire to tie the two dynamos together.

The Dickson Manufacturing company has some interesting history also.  Started in 1856 by Thomas Dickson in Scranton PA, the company produced stationary engine, blowing engines and steam powered mine cable hoists.  There was also a Locomotive division which Dickson is best know for.  In 1901, the locomotive division was merged with seven other companies to form the American Locomotive Company and the remaining steam engine operations became Allis-Chalmers.

The model is 1:20 scale which makes a lot of small parts, especially in the dynamos, but that was a trade off between making small parts and still having a manageable model.  Even at 1;20 scale, this model is going to be quite a lump with finished.  In hind site, I think 1:16 scale would have been easier to work with but we have too many patterns made now and parts cast to start over.

I will post some machining photos as soon as I learn how to work the posting process. 

Dennis
Title: Re: The Dickson!
Post by: maury on August 25, 2017, 03:54:27 PM
Jason, we are modeling the entire engine in Solidworks. The models are combined in an assembly drawing and tested for fit. We will also be making precise shop drawings for each part. The precarious part is if there is a mis-communication between Dennis and myself.

Actually, I am using a dummy tooling plate, that part in the Picture is a representation of the flanges, size, and placement.

The parts will have to be machined precisely per the drawing, but that is standard practice in all model building. That being the case, everything should fit properly.

The lagging is going to be cast into the pipe members. This simplifies the work during finishing the model. Guess we could have wrapped the pipes with paper covered with plaster, but that's messy.

It's way too early to think about paint, but the lagging will probably get paint.

maury
Title: Re: The Dickson!
Post by: sco on August 25, 2017, 04:13:18 PM
Dennis, Maury,

This looks like it will be a fantastic project to follow - thanks for posting the history and the modelling work done.

Best wishes,

Simon.
Title: Re: The Dickson!
Post by: Jasonb on August 25, 2017, 08:12:06 PM
Thanks Maury, I can see the way you are going now - a casting for each section of pipework including insulation with a flange on each end to be machined.

Looking forward to seeing some machining photos Dennis but would also be interested to see the patterns too.

J
Title: Re: The Dickson!
Post by: Dennis on August 28, 2017, 02:18:47 PM
Jason,
Here are some photos of the iron parts patterns I have cast so far.  I have been documenting the machining steps and including photos of the machining steps in the drawings I make, however they are difficult to share.  And when converted to PDF files, the files are much too large to post here.  Perhaps some time in the future when time permits we will make them available in a different way.   Solid Works is a wonderful and easy program to use and document a project, until your try to share the drawings with someone else who is not using the same year release as you are. 

The parts that have been cast and partially machined so far are the bed plate, foundation, field coil rings and field coil posts.

Title: Re: The Dickson!
Post by: Dennis on August 28, 2017, 02:29:18 PM
Hello everyone,

Here is a photo of the partially machined castings cast so far.  I have been working on the iron castings patterns and a prototype foundry in the Detroit area has been doing the casting.  All of the castings are ductile iron and machine very nice but quite messy. 

Maury has been working on the brass parts and making castings in his home foundry.  There are five brass castings and seven iron castings in each armature.  I have been slowly working at machining the first armature castings to prove out the design and patterns.  When complete, I update the drawings for John and Maury to use on their engines.

Dennis
Title: Re: The Dickson!
Post by: jeff l on August 28, 2017, 06:19:47 PM
Top notch pattern work and machining .
Title: Re: The Dickson!
Post by: Jasonb on August 28, 2017, 06:41:51 PM
That's looking very good Dennis. Could you give an idea of size, maybe the diameter of the ring?
Title: Re: The Dickson!
Post by: Zephyrin on August 28, 2017, 11:08:19 PM
I wonder why there are several wooden models (beautiful in their own!) that look identical, I would have thought it was simpler to make several molds (sand?) With the same model ...

It is really a grand project, wow !
Title: Re: The Dickson!
Post by: Dennis on August 29, 2017, 12:44:53 AM
Jason,

Here are some dimensions:

The field ring is about 10 inches in diameter, The foundation casting is about 15 1/2 in long.  When the model is complete with a dynamo on both ends, I thing it will be well over 100 pounds, already getting heavy with the parts in the photo.

Dennis
Title: Re: The Dickson!
Post by: Dennis on August 29, 2017, 01:12:43 AM
Zephyrin,

You make a good observation Zephyrn.  On the larger parts, like the dynamo ring, there is only one pattern, split between cope and drag of the pattern board and that works quite well.  That would be the normal way to get multiple cast parts.

Here is my thinking that led to multiple parts on one pattern for this part:

The pattern pieces you see multiple copies of in the photos are the pins for the field coils.  There are 14 field coils on each dynamo,  I just started machining the field coil posts so in a couple of weeks I will have a better photo to show that will make more sense.

I made 16 copies of the pattern so I could get the poles for one dynamo cast in one mold and still have a couple of spares to cover my mistakes.  The foundry I use has a minimum charge per mold which this pattern falls into because the parts only weigh about 1 1/2 pounds each.  Because the pattern for the field coil post is so simple and easy to make, I thought it would be to my advantage cost wise to have a full set of parts on one pattern.

We thought about just machining the parts from square bar stock because the end of the post is 1 1/2 X 1 3/4 inch but the ductile iron casting will have better magnetic properties than the steel. 

Hope this answers your question.

Dennis
Title: Re: The Dickson!
Post by: Dave Otto on August 29, 2017, 01:22:31 AM
Wonderful work guys, having worked with Maury on a project in the past I can only guess that you guys are having a great time!
I hope that Maury is keeping his feet dry through this terrible mess going on in Texas and the the other affected states.

Dave
Title: Re: The Dickson!
Post by: kvom on August 29, 2017, 03:00:02 PM
My experience with Dennis' Joy engine led me to believe that 100lb models are pretty hard to drag to shows if you fly to them.  This is the same Dennis who told me he was out of the large engine business because the castings were too heavy to manage.  I'm glad he's abandoned that idea, as this engine looks like a winner.   :ThumbsUp:

I've seen the original at the Henry Ford a couple of times, and in fact it was Dennis who pointed out that it used Joy valves.  The radius rod is so thin that it's hard to see at first glance.  Since the engine doesn't need to be reversed I wonder why they chose this type of valve.  :shrug:
Title: Re: The Dickson!
Post by: Dennis on August 29, 2017, 10:40:31 PM
Hi Kurt,

Glad you like the model.  I have been thinking about this engine since before we did the Gothic engine 20 years ago.  It is finally taking shape.

As you say, the engine would never be reversed in a power plant so it really doesn't need the Joy's Valve Gear, however, the engine itself was designed for marine use.  I do not know how many engines were built for the marine industry.  It was John Van Vleck, the chief engineer for Edison General Electric Company, who did the design work to adapt the two dynamos to the engine.  The photos and information I found of the Duane Street generating station shows seven of these engines with dual dynamos in the power station. Must have been quite a place.

And yes, I had to leave the model business because I can't lift the heavy castings any more, however I have a son who is willing to help occasionally.  I am building the engine a piece at a time and adding each part to the assembly, when complete I will invite my son to dinner and have him move it.
Title: Re: The Dickson!
Post by: Zephyrin on August 30, 2017, 08:34:42 AM
Hi,
thanks for the answers, I did not notice the spliced part of the coils frame.

Even if reversing is useless here, the advantage of a geared steam distribution, Joy's in this case, lies also in the possibility of notching and adapting at best the steam expansion and reduces coal consumption.

Title: Re: The Dickson!
Post by: maury on August 30, 2017, 06:36:29 PM
Dave, thanks for the concern about the storm, We were on the outskirts of it. There was a little wind, and rain for about 3 days, but the rain only totaled about 3". Conditions in costal areas are another matter.

I've been mostly hunkered down in the shop. Over the past weeks the CNC got a real workout. I've been making patterns for the castings for the Dickson piping. Over all, there will be about 35 castings or so. I've completed the match plates for the piping, except for the Governor Valve and Main Steam Valve, still need design work on those.

Some of the pipe parts will be made in halves so the interior can be milled out, then the halves will be silver soldered together before machining the flanges. These parts are small, and there will be a lot of 1-72 threading.

maury
Title: Re: The Dickson!
Post by: jeff l on August 30, 2017, 06:50:31 PM
Those patterns look great Maury .Jeff
Title: Re: The Dickson!
Post by: kvom on August 30, 2017, 09:54:25 PM
After all the 0-80 fasteners on my current project, 1-72 sounds big.   :LickLips:
Title: Re: The Dickson!
Post by: Dennis on August 31, 2017, 06:04:27 PM
Glad you area safe Maury.

The piping patterns look great, The cnc is really great for patterns like this.   A nice approach to making small complicated piping. 

Dennis
Title: Re: The Dickson!
Post by: maury on October 05, 2017, 07:51:23 PM
Well, folks, it's been a while, s o I thought I'd post a bit of an update.
Since I have been working on the valves and piping it has become evident
that some of the parts would not work with sand casting, leaving 2
alternatives. Investment casting seemed the only acceptable choice, so
I set about seeing how I could make that happen. Idid some reading and
talking with folks and also foundry. Well it came down to me having to set
up here at home.  I bought a burn out oven, but the accessories were harder
to come by. I ended up making the racks and tongs. I couldn't find the
proper size wax tray, and I don't have a finger break, so I had to settle
for a smaller one than I wanted. Here are some pics of the back end
equipment I have. On a later post I'll show making the molds, the waxes, and
the trees.

maury

Title: Re: The Dickson!
Post by: maury on November 19, 2017, 03:23:57 PM
Well folks, it's been a while, so I thought I'd give an update. The project is not dead.  It's cooling off a bit, so I am able to do a bit of foundry work. Unfortunately, I've been less successful on this project than some in the past. I seem to have trouble getting my sand molds to fill properly, and so far my investment casting has been a disaster.

Included are a couple of pics of castings. The piping and valve tops are done in sand, There has been some issues with filling, so I spread the parts between 3 patterns instead of 2, and improved the gating. Will be casting these new patterns before too long.

The second pic shows the 3 sizes of gate valves, the valve body being cast in investment. I have a few parts, none of which are really nice, but good enough to machine and verify the design. None of the valve handwheels have turned out so far.

Kind of a bummer, but making progress and learning a lot.
maury
Title: Re: The Dickson!
Post by: fumopuc on November 19, 2017, 04:26:59 PM
Hi Maury, I am following along with big interest.
Title: Re: The Dickson!
Post by: Dave Otto on November 19, 2017, 04:36:08 PM
Hi Maury

Looks like good progress, are the patterns for the investment wax or some other material?

Dave
Title: Re: The Dickson!
Post by: Jasonb on November 19, 2017, 05:09:31 PM
They look a lot better than quite a few castings we are expected to pay for!

Interested to see how you machine the U shape for the gate to slide in
Title: Re: The Dickson!
Post by: maury on February 28, 2018, 04:35:42 PM
Well, contrary to what it may seem, the Dickson is NOT dead.It's been a while, but what happened was I wasted a lot
of time and and investment trying to investment cast the valve bodies and handwheels. Sorry to say it was a complete
failure so I decided not to wast any more time on investment casting and redisigned the valve bodies for sand casting
and fabrication of the flanges.Also the handwheels are now being done on the CNC.

There are 3 sizes of scaled gate valves, and the engine needs a total of 9 valves. I have goof patterns that I have made
castings from, and have started machining them.
I'm including pictures of ine of them through the process.
1) the casting
2) Cutting the pass through to Dim.
3) I didn't show making the flanges from bar stock I cat, but here they are being soldered to the body.
4)Cutting the Flanges thickness to Dim.
5) Drilling the pass through.
6) Drilling and tapping the bolt circle on the Flange.The setup allows the other side to be done after centering.
7) Setup for the valve body top and cutting to dim.
8) Cutting the slot for the gate.

The bolt pattern is then drilled and tapped on the the top. Boring picture, but it really helps a lot
to have a DRO. If you don't have one you need to get one.

More on the valves later.
maury
Title: Re: The Dickson!
Post by: Mcgyver on February 28, 2018, 05:59:18 PM
Hi Maury,

can you explain a bit more whey the investment casting didn't work and what you think went wrong?  The stuff in post 32 looks great?  Investment casting is something I look forward to trying so am curious what happened
Title: Re: The Dickson!
Post by: maury on February 28, 2018, 08:39:49 PM
Mcgyver,thanks for asking. The bottom line is I just could not get my molds to fill. Those 3 valve body castings you see in post 32 were 3 of 4 out that molded ok out of at least 50 to 75 that I poured. I'll post a pict of the handwheel  later. I did everything by the book, that is the jewelry casting book suggested by another member on this board. I vaccuumed the investment before and after pouring into the mold, I used recommended  burn out times, poured the metal at the right temperature into the molds which were at the correct temperature, and on my final try, I even vented the waxes thinking there might be too much air getting into the mold. All no go.

Hope this helps,
maury
Title: Re: The Dickson!
Post by: Dan Rowe on February 28, 2018, 08:50:27 PM
Maury, were you using a solid flask on a vacuum table when you made the pour? I use 1/8" sprues for all but the smallest parts and the vacuum is needed to draw the metal into the mold.

Come down to my shop or I can visit you if you want to see my process.

Dan
Title: Re: The Dickson!
Post by: Mcgyver on February 28, 2018, 09:42:55 PM
Maury,
thanks for explaining more, I feel the frustration.  If nothing else I won't feel so lonesome if I have trouble.   I'm inexperienced but have been collecting the equipment and reading up on it.  The one thing you said that struck me was vacuuming before and after; I thought you vacuumed during the pour to pull the metal in as Dan notes?


Title: Re: The Dickson!
Post by: maury on February 28, 2018, 09:53:31 PM
Dan, thanks for the offer. I would like to hook up with you next time you do a pour. I can PM you my phone number, and I'll need a GPS address for you.

I don't have a method for pouring the metal under a vaccuum. This may be what my problem is. So, I thought the investment was porus enough to allow gravity to get the metal into the mold cavity. I am using 4" solid flasks, 4" high.


McGyver, I was using the vaccuum to get the bubbles out of the investment while making the mold. Not while I was pouring the mold.

maury
Title: Re: The Dickson!
Post by: Dan Rowe on February 28, 2018, 09:56:09 PM
The investment is mixed then vacuumed before pouring into the flasks. Then it is vacuumed again to remove any bubbles. This needs to be all ready to go as the working time of the investment is 12 to 15 minutes.

I have had trouble getting vacuum a few times before a pour and made the pour anyway... the results are usually disappointing.

We were posting at the same time. I will let you know the next pour I have.

Dan
Title: Re: The Dickson!
Post by: maury on March 04, 2018, 10:15:32 PM
So here are more parts for the gate valves. It seems the piping and valve work has been about as much as building a whole steam engine from a kit. Been having fun though, and learning a lot: even at my age.

1) This is the part I modeled and wanted to investment cast for the valve handwheels. This the only part which filled as well as it did, and the one of very few that filled more than about 50%

2)These are the Handwheels I made on the CNC. They are a 2 setup job, and take about an hour to cut. Multiple tool changes, and 3D milling The handwheels are about 1" in Dia.

3) The valve stem and the gate. The stem is made of .0925 drill rod with a collar soldered on. The thread going into the stem is left hand.
Title: Re: The Dickson!
Post by: Kim on March 05, 2018, 05:28:44 AM
Wow, Maury, those are beautiful hand wheels!  Well worth the effort.  Sorry the investment casting didn't work out as well as you'd have liked.
Kim
Title: Re: The Dickson!
Post by: maury on March 06, 2018, 04:12:18 PM
Kim. thanks for the compliment.

So, now I have completed 1 of each of the 3 sizes of gate valves.

Pics below.

maury
Title: Re: The Dickson!
Post by: b.lindsey on March 06, 2018, 07:12:02 PM
Those look great! Maury. Sorry the investment process didn't work but the sand cast bodied look the part for sure and then handwheels are beautiful with the CNC work.

Bill
Title: Re: The Dickson!
Post by: maury on March 06, 2018, 10:55:43 PM
Thanks for the compliment Lindsey, it's appreciated.

Working on some of the piping castings, I started with a simple one. The 10" scale extension pipe. It has 2 identical flanges, Drilled for 1-72 screws. The pics:

1) the casting
2) Facing the first flange in the lathe
3) Drilling the passage hole
4) cutoff finishes the lathe work
5) A setup is needed to make sure the flanges are centered on the casting and they line up end to end.
6) Using the DRO I first center drilled the BC, then drilled the 1-72 clear holes. Don't have another pict, but I flipped the
part, aligned with the lower BC, then drilled the upper BC.

maury
Title: Re: The Dickson!
Post by: maury on March 15, 2018, 01:50:37 PM
Making the pipe_8_8_8_8 was a little more challenging. there are 4 flanges, all the scaled 8" size, but must
be in alignment on the through passage. The other 2 flanges must be perpendicular to the through flanges , and
have different ofsets. The fully assembled piping structure is bolted to all 3 cylinders, and is hard, as in
no adjustment to the structure. it is critical that each piece is spot on dimension.

Additionally, the part includes a difficult coring challenge. I avoided that by making a 2 piece casting set,
requiring the machining of the passage way and subsequently soldering the parts together. This has actually
worked out quite well. Other parts in the piping part of the Dickson project also use this method.

After the part is soldered together, it may be machined as a regular casting.

1) cutting the passage uses a 1/4" ball endmill, and is cut to a depth of .125. This of course gives a 1/4"
Dia passage. Note, the passage is not milled to an accuracy that will allow using it for a reference to later
operations. The OD of the flanges is carefully measured and used, the BCs on these flanges will be centered
on this OD measurement.

2) The halves soldered together. Note, the parts were sanded with rough sandpaper on a flat surface before
 the passages were cut. The castings were good, and it was not difficult getting a flat clean surface.

3) First OP: I didn't show a setup pict. but the part is setup in the vise with the tops of the 2 pass through
flanges parallel to the X axis of the mill. Measurements in the Z are setup on the Z DRO, and the flanges are cut.

4) The Bolt Circles are drilled

5) Second OP: The vise holding the part is then rotated in the Mill vise, exposing the next flange to be cut,
and keeping everything square. Next the vise is rotated again exposing the final flange.

Hope this gave some ideas for those challenging casting setups.

maury
Title: Re: The Dickson!
Post by: maury on March 16, 2018, 07:07:00 PM
Hi Folks, well there has been a lot of plug & chug here. The piping sub assemblies are coming together. I need more castings to finish the valves and my knee is out of commission, so it may be a few weeks. I still have the governor and a couple  more pipe fittings to build, will keep me busy for a while.

I'll be glad to get to the next phase of the project, there are lots of bolt patterns to make on these parts, and over 200 tapped holes. Almost all are 1-72. Still having fun.

1) Pics 1,2,3 are the High Pressure Cyl to Intermediate Pressure cyl  piping connections.
2) Pics 4,5,6 are the Intermediate pressure to Low Pressure cyl piping connections.
3) Pics 7,8 are the Exhaust piping connection from the Low pressure cyl.

maury

Title: Re: The Dickson!
Post by: maury on March 20, 2018, 08:55:16 PM
OK Folks, a little shift away from working on the piping. I have the drawings from Dennis for the base parts of the Dickson, so I thought I'd start on the crank shaft. I need to fettle the castings before I start on them. I made models of the crank parts in Solidworks, Also changed the design a little I won't be exactly scale because of this, but I wanted to make the crankshaft shaft with a single piece of drill rod. The original engine design has the crank shaft built in 3 pieces and bolted together with flanges. My experience tells me I won't be able to make that design accurate enough without the crank binding a bit.

I had a couple of busy days in the shop with 4 machines running. Had a great time. Here's what I've made so far.

1) I ran the model for the crank bell on the CNC. (actually did this 6 times). I chose to use round stock.  So to prepare the stock I faced  both ends of a piece in the lathe to get a parallel surface with a good finish for the face. I ran the part in the CNC, then used the band saw to cut it off a bit proud of the needed Dim.

2) I also made a Solidworks model for a tool to face off the other face. The pattern is a few thou bigger than the bell, and uses 2 set screws to hold the part in while facing. The bells were faced to Dim.

3) The 6 crank bells then needed the holes reamed because my CNC has a bit of backlash and the holes are not only not exactly round they are not quite the right size. Fortunately, they are smaller than Dim. I want a medium press fit with the shaft. After assembly, the bells will be pinned to the shaft.

Next time the counterweights, They should be even more fun.

maury
Title: Re: The Dickson!
Post by: maury on March 21, 2018, 08:48:04 PM
Well Folks, another fun day in the shop. Today I worked on the Crankshaft counterweights. I had to diddle with the geometry a bit to get a nice tight fit between the bell and the counterweight to compensate for the backlash in the CNC. Hit it on the first try. I was able to cut two parts before my tool showed too much wear to go on. it is an old 3 flute carbide tool, and it has made a lot of steel parts. ( Chuck: if you are tuned in could you send me the contact info for the tool place in Round Rock please? )

I used a 3D tool path to avoid making any heavy cuts, balanced with cutting air. The part is about a 1 1/2 hour run.

1&2) CNC cutting the part.

3) The counterweight after being cut off in the band saw and facing the back face in the lathe.

4)The counterweight and bell assembled. I was planning to use set screws to hold the parts together, but  they fit tight enough that I may use LockTite.

maury
Title: Re: The Dickson!
Post by: Dave Otto on March 21, 2018, 11:50:35 PM
Nice looking parts Maury!


Dave
Title: Re: The Dickson!
Post by: maury on March 23, 2018, 12:04:20 PM
Dave, thanks for the compliment.

Also looking forward to seeing more of your excellent work. Max tells me the Pacific is getting lonely.

maury
Title: Re: The Dickson!
Post by: Dave Otto on March 25, 2018, 04:53:29 PM
The Pacific is lonely, I havent been able to work on it since I made the pulley back in November. Part being busy with other projects and part procrastination.
Max walked by it the other day and mumbled something about that thing needs some paint. :lolb:
Hopefully I will get back to it soon.

Dave
Title: Re: The Dickson!
Post by: maury on March 30, 2018, 03:51:48 PM
Moving along on the crank shaft, I am assembling the 3 throws as sub-assemblies before
assembling the whole crankshaft.

1) The Throw parts. The new part is the little shaft made from drill rod. It has a tight
press fit into the crank bells.

2) The Throw tool holds the shaft vertically while pressing. I use a manual press, one of the
cheap ones, and while pressing it seems to like skewing the components off vertical. The tool
helps that.

3) Ready to press.

4) After pressing one crank bell to the shaft, the second one is aligned with piece of drill rod.
The fit is a light press.

5) the finished crank throw.

maury
Title: Re: The Dickson!
Post by: Admiral_dk on March 30, 2018, 06:14:13 PM
Interesting jig for assembling the throws  :ThumbsUp:
I'm guessing that you will make another to assemble the complete crank .... will it also have features that ensures that the throw angles are correct or  :thinking:
Title: Re: The Dickson!
Post by: maury on April 02, 2018, 02:23:37 PM
Admiral, thanks for the question. Actually, I was going to make a 60 deg. jig to hold the frank
 for drilling the holes for pinning the throws to the crank, but the light turned on. I ended up
using the spin index. Worked out well. I'm including pics for the setup of each throw, and some
shots of the finished crank.

maury.
Title: Re: The Dickson!
Post by: Admiral_dk on April 02, 2018, 09:36:18 PM
So if I understand the pictures correctly - you pinned / screwed the throws onto the shaft - though I do not see the evidence on the last pictures  :thinking:

Thanks and best wishes

Per
Title: Re: The Dickson!
Post by: Dennis on April 02, 2018, 10:53:22 PM
That is a nice looking Crank shaft Maury.  I really like the way you put the parts together and the idea for setting the rotation angle on the individual cranks.  Did you use the 308 stainless for the crank parts? 

Dennis
Title: Re: The Dickson!
Post by: b.lindsey on April 03, 2018, 01:07:19 AM
Wow, very nice looking crankshaft maury!! All these details are going to make a fine looking model for sure

Bill
Title: Re: The Dickson!
Post by: maury on April 04, 2018, 02:50:18 PM
Guys, thanks for all the nice comments!

I guess I was in a bit of a hurry when I posted last.
As I said I used the spin index to get the proper rotation of the cranks. So What I did was to position the first throw on the shaft using Locktite262. After hardening, I drilled and reamed the pin holes for .125 pins. Then rotated the spin index 120 deg. and repeated the process for the other 2 throws.

The reason the pins don't show on the final pic is because they are covered by the counterweights. I thought it more attractive to hide them.

The materials I used were:
Drill Rod for the shaft parts, I like it because it's ground to a nice finish and it's harder than the usual softer steels.
I had some 1144 in my bin, this is my favorite steel to use for most general applications because of the finish I get and the nice way it machines. Also, machined this dry. Almost like cast iron but without the mess. I used it for the counterweights
The throws were made from 1018 because I had some of the size I needed. I will use 1018, but it's gummy and doesn't give a great finish with using oil. Thus a mess.

maury
Title: Re: The Dickson!
Post by: gbritnell on April 04, 2018, 07:25:01 PM
HI Maury,
Great work as usual! I really like the crankshaft.
gbritnell
Title: Re: The Dickson!
Post by: maury on April 05, 2018, 05:11:13 PM
George, Thanks! I appreciate the compliment
maury
Title: Re: The Dickson!
Post by: maury on April 09, 2018, 10:07:59 PM
Hi Folks, I cut the pattern for the drag side of the Low Pressure cylinder today. Dennis is designing these parts and sending me .step files so I can run them on my CNC. This was a 3D run, and was about 8 hours. It is made from REN, a really nice material for making foundry patterns. I used a 3/8 tool for roughing, 1/8 for rest roughing, and a 3/16 ball end mill for finish.

maury
Title: Re: The Dickson!
Post by: J.L. on April 10, 2018, 01:07:05 AM
HI Maury,
Absolutely stunning work.
John
Title: Re: The Dickson!
Post by: Dennis on April 22, 2018, 10:26:19 PM
Hello everyone,

Finished up the patterns and core boxes for the 6 columns for the Dickson model last week and got them to the foundry.  Here is a photo of the pattern for the three front side columns and their core boxes.  These are simple "strike off" core boxes cut on my CNC router.  The pattern pieces were also cut on my CNC router.  I will post photos of the parts when they are cast but not sure when that will be.  The foundry looked busy and I didn't ask the lead time, just grateful they will still cast my small volume parts.

The High pressure and intermediate pressure cylinder patterns are being assembled in the shop now.  Maury machined the pattern pieces from REN board and it is really nice to work with.  First time for me with the REN board, wish I could afford to use it more but it is quite expensive.  The core boxes for the cylinders and steam passages are much more complicated than the column core boxes.  The cylinder core boxes are made in two parts and they will be closed with several vents on one side and multiple high pressure fill tubes on the other side.  Not sure what this process is called but it makes a very dense and strong core.  The foundry guys taught me about this process when I was having trouble making cores that would hold together for the compound condensing marine engine river gypsy built.  I will post some cylinder pattern and core box photos when one of them is finished. 

Dennis
Title: Re: The Dickson!
Post by: 10KPete on April 23, 2018, 02:36:27 AM
Sodium silicate or CO2 cores.  Wonderful invention.....

Pete
Title: Re: The Dickson!
Post by: maury on April 23, 2018, 06:57:35 PM
Dennis, great looking core box.

10K, you can't use sodium silicate on iron, it will fuse like glass and you will never get it out. Actually, it might even melt and deform. I believe the foundry is using either baked cores or Air set sand.

maury
Title: Re: The Dickson!
Post by: 10KPete on April 23, 2018, 07:13:36 PM
Dennis, great looking core box.

10K, you can't use sodium silicate on iron, it will fuse like glass and you will never get it out. Actually, it might even melt and deform. I believe the foundry is using either baked cores or Air set sand.

maury

Maury, the silicate is not used alone in making a CO2 core. There are other additives/factors which are used/accounted for in using this system, which was invented/patented around 1959. Silicate cores have been used for iron since day one.

Here is some basic information on the system:

http://www.hillandgriffith.com/green-sand-metalcasting-foundry-news/sodium-silicate-binders

https://www.budgetcastingsupply.com/product-p/1025-qt.htm

https://patents.google.com/patent/US2883723

I hope this helps,

Pete
Title: Re: The Dickson!
Post by: Dennis on April 23, 2018, 10:01:11 PM
Pete,

Thank you for the additional information.  I will make good use of it.  My pattern making and foundry experience is from trial and error so every little bit helps.  I make something and when it doesn't work the guys at the foundry are kind enough to explain why.  Wonderful people and I have been working with them for 20 years now.

Dennis
Title: Re: The Dickson!
Post by: maury on April 26, 2018, 08:52:20 PM
Guys, Thanks for all the nice comments. I decided to jump in on the main castings for the Dickson.
The base Plate seems like a good place to start.

1) the casting was a bit rough, so I did some initial fettling to get it where I could get a good
setup for the first cut. This is important because everything will be referenced to it.


2)Bearing Mount Holes: After the first cut, the casting was fettled some more to get a good top side
setup.This setup was maintained for the remainder of the machining of the part. The column pads and
main bearing cap pads were machined to finish height. Then the stud holes for the mains were drilled.

3) Base Mount Holes: The base mounting holes were located and drilled. There were small discrepencies
between the Dims and the locations of the pads on the casting.So I centered the holes on the pads and
recorded the dims on the drawing for future use on the foundation casting.

4) Mains: Since the stud Holes intersect the trough for the mains, they were done first. Then the
trough was cut to Dim.

5) Columns: Notice the hankypanky with the clamps. They were moved one at a time to preserve the setup.
Had to do this twice. I did sanity check the setup with the DRO before proceeding each time.The 48 column mounting holes were drilled and tapped. a bit tedious.

6) the machined bed plate.


maury
Title: Re: The Dickson!
Post by: crueby on April 26, 2018, 09:12:27 PM
Great job on the base, thats a lot of holes to get lined up.   :ThumbsUp:
Title: Re: The Dickson!
Post by: maury on April 27, 2018, 04:28:41 PM
Crueby, thanks for the compliment.
If it weren't for my DRO I would never have been able to Get all those holes right. Thanks for technology.
maury
Title: Re: The Dickson!
Post by: Dennis on June 03, 2018, 07:55:29 PM
Hi everyone,

Last Friday, I picked up the cast columns, bearing caps and cylinder heads for the Dickson engine model.  Did some trimming on the castings and the first set of parts (in the photo) will ship to Maury Monday morning.  Still with a lot of trimming to do.

In the photo, the in-gate for the columns is at the top of the column.  I left most of the gate on the parts in case we wanted to use it to clamp the columns down for machining.  The workers at the foundry cutting off the gating can get a little heavy with their grinders and saws so I always tell them to trim the gates at least a half inch from the part.

The cylinder heads all have a large chucking post on the back side which makes them easier to hold for machining.  I left the bearing caps attached to a strip of runner so they wouldn't get lost so easy.

The three cylinder patterns and core boxes are being worked on now.  They are nearly finished so at least one of them should be at the foundry late next week to see how the pattern and core box are going to work.  We want to be sure the cores in the steam chest area and steam passages will be strong enough before running all of the patterns. 

Dennis
Title: Re: The Dickson!
Post by: sco on June 03, 2018, 08:26:37 PM
They look nice and crisp!

Simon.
Title: Re: The Dickson!
Post by: maury on June 04, 2018, 04:11:31 PM
Dennis, great looking castings! I know the columns were a particularly interesting challenge because of the cores and curved parting line. Great work. Can't wait to get some.

maury

Title: Re: The Dickson!
Post by: Dennis on July 25, 2018, 08:18:38 PM
Hello everyone, I can't believe how long it has been since I updated the Dickson build, but we have been working on it.

This afternoon I went to the foundry to pick up castings for the HP and IP cylinders.  There are photos below.

Photo 1. the pattern for one of the cylinders.  I only put one cylinder on each pattern board. I was concerned there would be a lot of bad castings at the foundry because of the small internal passages I tried to cast into the part.  However, that wasn't the case

Photo 2. the assembled core box for the internal piston valve steam passages and the cylinder bore.  The core sand is blown into the mold under pressure and I am told this makes a stronger one piece core. 

Photo 3. the core box opened up.  The cores are about 3/16 inch thick in the thinnest areas so I was trying to get the strongest core I could.  When I was walking through the casting area, most of the cores there could be measured in inches, not 1/16ths.  It takes more work to make the core box this way but the results are really good and there were no bad castings at the foundry.

Photo 4. Finally, the HP and IP cylinders as they came from the foundry.

One more pattern to go, the Low Pressure cylinder.  The LP cylinder core is even more complicated because there are two sets of piston valves to get the volume of steam needed for this large cylinder to operate.  The cylinder bore, and each of the piston valves are on separate planes so a simple two piece core box won't work.  The pattern is about 80% complete and I will post photos when it is done.

I have also been updating and making additional drawings for the project.  Up to 240 sheets so far.  Everything has been checked for clearance as far as I can with Solid Works assemblies which is quite a lot.  However I am sure there will be a lot of corrections to the drawings as we machine more parts. 

I'm looking forward to getting back to the metal side of the shop to machine some of these castings.

Dennis
Title: Re: The Dickson!
Post by: maury on September 07, 2018, 09:03:47 PM
After setting the Dickson aside for a couple of months, it's time to get back to work on it. I was waiting
for Dennis to finish up the shop drawings for the columns and valve gear.There are over 200 pages of
drawings, so he has worked quite fevorishly on this task. I was working on the Tank cooled mogul during
this time, when I get some time I might post the progress on it.

So the work on the columns is an interesting challenge.These castings don't have any easy ways to hold in
the machine for work, so I thought I'd post what I did. Don't know if this is the best way, but it seemed
to work.

Step1: machine the flat surface for the cross slide. This will be a reference for all other machining
of the part. The height of the back of the foot is measured, and the height of the back of the top foot
is added. A spacer is made to raise the back of the top foot to the calculated height, and the cross
slide is machined to the calculated height.

Step2: The Feet are machined. With the part clamped parallel to the front plane, it must alsp be aligned
with the right plane.This is done by measuring and centering 2 sets of features, The insides of the feet,
and the width of the casting at marked points near the cross slide. This step is tricky and precrious and
care must be taken.The feet are then machined to thickness and trimmed to their proper size.

Step3: The easy part. The DRO is setup and the mounting holes are drilled.

Step4: After the feet are machined, the part is set up in the top plane and right plane using the 2 machined
surfaces.The cross slide for the valves is machined to height, the the DRO is set up again.

Step5,6: The holes for the cross slide caps are drilled and tapped.

Step7.8: Time to make the slots for the valve gear. Using the same setup, the slots are milled.

The tops of the feet will have to be cleaned up a bit for the bolts to fit down nice. After all the columns
are machined they will be assembled to the engine base for machining the tops and the pads which are at
angles on the fronts and backs. This will be for another day.

maury
Title: Re: The Dickson!
Post by: Dennis on September 08, 2018, 11:39:54 PM
Big step forward Maury!

Thanks for posting the photos,  the best way to machine a part is the way that works for you and the resources you have. 

I like the way you machined the column and will be following your lead when I get to machining my columns.  Securing that casting to the milling machine table is a real challenge when the only flat cast surface is the first surface that needs to be machined.   I'm going to look at the drawing sequence and make sure the multiple drawings for each column follow the machining sequence you used. 

It is really good to see some more parts taking shape. 

Great work figuring out the column machining.

Dennis
Title: Re: The Dickson!
Post by: mechman48 on September 09, 2018, 11:33:11 AM
Very impressed with the progress so far; read through your write up so far, well thought out & presented, inc. pics...  :drinking-41: look forward to eventually seeing the completed model in operation :ThumbsUp:

George.
Title: Re: The Dickson!
Post by: maury on September 14, 2018, 10:00:52 PM
George, thanks for the nice comments.

Interesting week on the CNC. I have made tool paths for about half a dozen parts for the valve gear, and decided to start with the levers. I think these are the hardest and most precarious parts in the valve gear. Mostly because of their size. It took a few tries to get the tool paths tweaked in so I liked the results. Most of the work was done on the CNC, but I finished up on the Bridgeport.

Maury
Title: Re: The Dickson!
Post by: Ye-Ole Steam Dude on September 14, 2018, 10:14:57 PM
Hi Maury,

Nice work and good looking parts.

Have a great day,
Thomas
Title: Re: The Dickson!
Post by: maury on September 16, 2018, 07:28:36 PM
Thomas, thanks for the compliment.

Well, I worked up a CNC job to make a cross slide part for the Dickson. It is a 3D job with 2 setups. The first one turned out badly, due to excessive backlash on the Y axis. I adjusted it best I could this morning, and made the second part. it turned out usable, but not really what I would have liked. I think I will have to be replacing the ball screw and thrust bearings on the Y axis in the not too distant future, or just maybe ask Santa for a new machine for Christmas.

The part:

maury
Title: Re: The Dickson!
Post by: 90LX_Notch on September 16, 2018, 10:13:42 PM
Following along Maury.

-Bob
Title: Re: The Dickson!
Post by: maury on September 17, 2018, 11:01:11 PM
Folks, had a break from the CNC today and back to the lathe and mill.
I made some valve linkage parts, all from 303 stainless.
The linkage is the adjustable part in the linkage, and the screw is RT hand on
the lower end and LH thread on the upper.

maury
Title: Re: The Dickson!
Post by: Dennis on September 19, 2018, 08:19:40 PM
Good progress Maury,
Dennis
Title: Re: The Dickson!
Post by: maury on September 20, 2018, 09:10:50 PM
Dennis, thanks for the comment.

Back to the CNC, thought I'd work on the rockers. THis is a difficult part to hold, so As I posted earlier, I made a new fixture. I'm using 3/8 square 303 stock. Was planning to make the part out of 1/8 stock and use a screw to hold the post on. decided to 3D the whole part. This is the first time I used the tab feature in my BobCam. nice feature. Also, to avoid cutting the fixture, I put some .008 brass shim under the stock. Seems to have worked out nice.

maury
Title: Re: The Dickson!
Post by: maury on November 19, 2018, 09:29:14 PM
I finally made the trip to Houston to get my foundry sand mulled. It is so much better now.
So I did a Bronze pour and made some castings for the Dickson.
I've been wanting to get the crank I made put in, so I cast the Mains and the Con Rod parts.
Working on the mains first.

To start with I worked on the lower bronzes.

1) the shaken out casting, turned out good.
2) the parts cut off and cleaned
3) The bar stock is squared up and the first cut is for the side notches.
4) Second cut is the bottom notch
5) The finished part. The bore will be dine with all the bearing bronzes assembled to the base.
6)The end lower bronze is fitted to the base. The fit is quite snug, and is had to be tapped into the base.
7)All of the lower bronzes fitted to the base.

maury
Title: Re: The Dickson!
Post by: Ye-Ole Steam Dude on November 19, 2018, 10:15:55 PM
Hi Maury,

Those castings sure do look nice.

Have a great day,
Thomas
Title: Re: The Dickson!
Post by: maury on November 24, 2018, 10:49:19 PM
Thomas, thanks for the compliment.

I'm back from the Thanksgiving trip, so I thought I'd post a bit more progress.

I've finished the upper mains, or bearing caps. The photos show some of the steps along the way.

Next step is to order a long 39/64 drill to bore the mains. I have a .626 reamer. Next post will show the setup and steps.

maury
Title: Re: The Dickson!
Post by: crueby on November 24, 2018, 11:48:56 PM
Very nice progress! Looking forward to seeing how you do the boring, going through that many bearings always makes me pause and think. A lot.
 :popcorn: :popcorn: :popcorn:
Title: Re: The Dickson!
Post by: maury on December 01, 2018, 08:59:25 PM
Cruby, thanks for the compliment.

Boring the mains is not as much a challeng for me as it is for my equipment.
I have a Bridgeport, and still had to improvise. The 39/64 drill came in yesterday, I already had
the .626 reamer, so I got started.

1) The first pic shows the main setup jig I used. I have a square tower block that I used to hold the
engine base. I needed it to be above the table a bit, so I raised it a bit. The tower isn't exactly
square so I had to shim the base a bit to get everything square with the table. This took a bit of fiddeling,
but it wasn't bad.

2) After that I found the zero on the bearing, and set up ther DRO in case my  work was interrupted.

3) Center Drilling where the hole will be bored.

4) Since my Bridgeport can't accomodate a 12" drill on top of the base I have, I used my 39/64 Jobber drill
to start the hole. I was able to drill the top 2 bearings and start a nice centering hole for the long drill.

5) With the table all the way down, I removed the top 2 bearing caps and was able to get the long drill
into the chuck.I was able to complete drilling all the bearings.

6) Reaming, the reamer was shorter, and fit into the space if I used a collet to hold it. All the bearings
were reamed.

7) Finish on reamed bearings.

8) There was a generous amount of burring on the soft leaded bronze. I cleaned up the parts, and assembled
the crank to the base and added the caps. The moment of truth! Did I bore the holes straight, and did I
get the crank straight? It turns out the fir is silky smooth through the rotation, and just a little bit
snug to turn. I probably could have used a .627 reamer, but I didn't have one. I've found that when reaming
soft leaded bronze, the fit may be a little tight. It'll wear in nicely.

maury
Title: Re: The Dickson!
Post by: 10KPete on December 01, 2018, 11:12:29 PM
That's just beautiful!!

Pete
Title: Re: The Dickson!
Post by: b.lindsey on December 02, 2018, 01:13:19 AM
Awesome Maury!!  Had missed a few posts but caught back up again now.

Bill
Title: Re: The Dickson!
Post by: PJPickard on December 02, 2018, 03:14:20 AM
OK now that I found this thread I will be following closely!
Nice work!
Title: Re: The Dickson!
Post by: Dennis on December 02, 2018, 03:44:13 PM
Really good work Maury, thanks for posting your progress on the crank.  I have been looking forward to seeing that assembly.  You are getting way ahead of me!  I like the way you made the bearings and crank shaft, and the assembly looks perfect.  I am working the drawings and photos you sent me into the drawing package so all the options will be there. 

My crankshaft material is cut and squared with the machining centers in the ends.  I decided to make the machined crankshaft because I have never done that before.  I'll never learn any younger.

I will be looking forward to seeing your base with the columns and cylinders installed.  The low pressure cylinder pattern has been at the foundry for 7 weeks now so we should have parts soon.  I know they are very busy and our pattern is not the highest priority.

Paul, glad you found the Dickson thread.  Welcome, I hope you enjoy following it.  Maybe we will see a new thread on your compound engine one of these days?
Dennis

Title: Re: The Dickson!
Post by: J.L. on December 02, 2018, 03:54:38 PM
Incredible work!
John
Title: Re: The Dickson!
Post by: maury on December 07, 2018, 11:10:58 PM
Hay guys, Thanks so much for the compliments, I appreciate them a lot.
]So, I have some progress to report in the con rods. I have completed one, and will finish the con rod assembly on my next post.
here is the progress on the  cross slide and the  throw bearing parts.

1, 2, 3 ) The cross slide part was made on the CNC, but there was material left over to be trimmed off to match up with the cross slide bearings on the columns after they are machined. This will happen in a later post. The original drawings show the part to be more than 1 piece, but since there are no cross slide shoes on this engine, I made it in 1 piece to simplify the construction.

4) The castings are fettled, drilled and tapped, then cut with a 1/16 saw in the Bridgeport.
5) Then, they are mounted in the lathe, center drilled, and drilled for boring.
6) Boring to about .01 under size.
7) Reaming to final size: .626

maury


Title: Re: The Dickson!
Post by: steamer on December 16, 2018, 04:15:58 PM
Maury.....this is great    watching along!
Title: Re: The Dickson!
Post by: maury on January 13, 2019, 09:18:01 PM
It's been a while folks, so I thought I'd give an update on the Dickson. Still haven't gotten the LP cylinder casting, so I'm trying to make progress on the valve gear. This is an intricate contraption, and I'm not sure I fully understand how it works. I have made all the parts for the HP cylinder, and have fitted them to the engine base ans columns. After working through a few minor interference issues, it does seem to work. The true test will happen when I actually try to get it to run. The CNC has been busy, and will be even busier this week when I will be duplicating those valve gear parts for the other 2 cylinders.

I have a few shots of the lower engine assembled with what I have completed so far. Enjoy.

maury
Title: Re: The Dickson!
Post by: Dennis on January 29, 2019, 03:48:58 PM
Hi Maury, Thanks for posting the assembly photos for the Dickson, I have been wondering how it would look as the columns went on and it looks really nice.  I talked with the foundry this morning and they are having problems with the LP cylinder cores.  We are going to get together next week (after the cold breaks) to figure out another way to make the valve cores.  With two piston valves in the cylinder casting, the internal passages are quite complicated.  It seems that every time the foundry teaches me something new, we push the design detail a little farther and get in trouble again.  Looking forward to next weeks meeting and learning more.
Dennis