Boiler Build For American LaFrance Engine

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Hi Larry,
Go to McMaster & Carr and type ceramic insulation in the search engine. Several types should work well for your project.

Kaowool, I've answered in teh other thread

Thanks Dan :bow: I just checked out what they have. I think I will get the 1/16" thick by 3" wide material. This way I will not have to cut holes in ONE BIG piece.

I can not say I am looking forward to making the otter wrap from the sheet steel that all the other LaFrance engines have. It is one of those operations I have not been able to see my way through. So, I am thinking of using the the ceramic insulation you so kindly guided me too and covering that with vertical red mahogany boards. Then hold them in place with the typical brass bands. Any thoughts and/or comments ?
Put the insulation material under teh cleading steel, its the way full size engines were done but they used timber. Exposed boards were mostly on stationary engines nor traction engines or pumpers.

I've just spent the last 2 weekends doing the brass clading and boiler bands on my Traction engine

Yes, JasonB, deep down in my heart I know that steel cladding is the thing to do. I will probably will do just as you say. I'll save the wood cladding for the stationary boiler that is sitting on the shelf. But I had to ask. Thanks !
I did receive some copper tubing from Coles Power Models a few weeks ago. It was not what I ordered. I wanted 5/16" OD by 22 gauge (0.028") wall thickness. They sent me what the print called for instead, 3/8" OD by 20 gauge (0.035") wall. So I called them and requested what I needed again and why. I sent the 3/8" tubes back for a refund. I received a package a few days ago with 5/16" OD by 18 gauge (0.048") wall copper tubes. I called again and the lady who takes the orders was highly disturbed to say the least about my order. I can not believe that someone would take tubing off the rack and just blindly cut and send out without measuring first. It boggles my mind :eek:

Anyway, the bottom line is; I do not believe they have the exact size I need. I plain to call back in a couple of days to check for sure. So I am planning to use a 0.250" diameter drill through the entire length of the tube (6.0"). I will drill from both ends. Then I will use a Letter"F" (0.257") reamer for at least 1.5" to bring each end to size for my tube roller. The minimum diameter for the tube roller is 0.254"

I am open to any thoughts or suggestions !

I have rough cut the two tube sheets from 1/4" plate. The attached picture show the first one in the lathe. I do something that I call pressure turning. I run the jaws out fairly close to the finished diameter of the work piece. Then I use the live center to hold the plate against the jaws.

I talked with the folks at Coles Power Models this morning. They did confirm that they have the copper tubing I have requested twice, but for some reason they seem to be unable to follow through. Since they indicated that they would not be able to sell what I have, if I returned them, I decided to make do with what I have. I will proceed to drill out and ream the tubing to the size I need. I hate to see good materials go to waste. It takes about 1-1/2 minutes to do one tube.

On with the build ;D

Picture #1 shows the results of the turning I started in the last posting. Left to right; boiler top tube sheet, mud ring and then firebox tube sheet.

Picture #2 shows the last hole being drilled and reamed to size in the top tube sheet.

Picture #3 shows a mock-up with the mud ring on the bottom of the firebox and the tube sheets in their basic location with each other. In the foreground is a drilled and reamed flue tube with the tube roller partial inserted. The outer shell needs to have some tabs welded on it for other attachments. I need to remove a couple of bushings at the mud ring area. They are in the way of the coal bin. Then I need to locate the fire box opening. The fire box will be welded in place and then the hole for feeding the fuel into the firebox will be made in both pieces.

Picture #4 shows the tube sheets in their respective location.




Good Evening, been busy all day TIG welding boiler pieces together. For those of you that are not familiar with TIG welding, let me give a brief explanation. TIG stands for "tungsten inert gas".

Picture #1 shows a typical TIG torch head. The handle and head portion is water cooled. The pink colored item is a ceramic cone or nozzle. There is a tungsten electrode with a sharp point barely sticking out of the nozzle. The work piece is grounded as in any typical welding process. When you activate the foot pedal to start the welding process, argon gas starts to flow and floods the immediate area to be welded. Then the current is applied to the electrode generating a plasma arc. As the current is increased the metal starts to melt and pool very much like when soldering with a tin/lead solder. There is two basic processes in TIG welding. The first is fusion welding. This is when you melt the metal of the pieces you want to join together without any filler material. The second process is a fillet weld. Same process as the first one mentioned but a filler material is added to the pool that has been generated to increase the amount of material at the weld joint. There is no smoke, splatter, scale or fumes generated with TIG welding. It is a very controlled and clean process and you can see what is taking place all during the process.

OK, on with the build; Picture #2 shows the pieces for the fire box entrance way. Beside the pieces is a "slugger cutter". It is the same diameter as the outside radius of the firebox entrance pieces. I will use the slugger cutter to make the penetration into the outer boiler shell and firebox. I will post some pictures of this process later.

Picture #3 shows the pieces mentioned earlier tack welded together. Again, all I had to do was to place the tungsten electrode over the joint and apply the current. Both side melted together.

Picture #4 shows the beginning of what I call the 'root" weld. This is a fusion weld as described earlier. After the work piece cools, I will come back and add filler material to complete the welds.

Continued to next posting.




Continued from Reply #67

Picture #1 shows the mud ring in place with the beginning of the root weld. I like to do short sections opposite each other to help distribute the heat evenly throughout the work piece. After completing the root weld, I will let the piece cool down completely before doing the filler weld.

Picture #2 shows the completed root weld of the firebox tube sheet. Beside it is the firebox entrance assembly ready for machining.

Picture #3 shows the firebox with the tube sheet and mud ring welded in place. The 4 ears are for keeping the firebox on center with the outer shell during the welding process of the mud ring to the outer shell.

Continued to next posting.



Continued from Reply #68

Picture #1 shows some of the threaded studs that protrude into the pressure side of the boiler. What I do is to take the TIG torch head and hold it vertical over the stud, apply the current and slowing melt the stud material down to the inside of the boiler shell. All the while I am doing a slight circular motion.

Picture #2 shows the results of the welding process as described.

Picture #3 shows the firebox in place and the root weld has been performed. At this point I am letting it cool down to room temperature before doing the fillet weld.

Picture #4 shows the completed weld joint of the mud ring to the outer shell.

The next thing to do is to set the assembly up in the milling machine and make the opening for the firebox entrance way.

Thank you so much for your interest.




Giovanni, thank you very much for your kind comment.

I had a little time to spend in the shop today, so I made the hole in the boiler for the firebox entrance way.

Picture #1 shows an aluminum block with four 5/16-24 bolts in each side. The bolts have a slight crown to them so they can be tightened against the inside surface of the work piece. The center hole was drilled exactly on center of the block. I change out the bolts as needed for other sizes of tubing and pipe. The block is very tight inside the firebox. It will not move !

Picture #2 shows the boiler set-up in in the indexer and the slugger cutter ready to do its thing. I did add a parallel to the underside of the boiler on the centerline of the cutter for more support.

Picture #3 shows the results of the first pass of the cutter through the boiler and firebox. The round disc sitting just to the right of the hole is the slug that was generated from the boiler shell. The slug from the firebox fell into the firebox as the cutter went all the way through. I then moved the boiler 0.210" off center in each direction on the "Y" axis to get the hole I needed as shown in Picture #4




Thats comming along well. How do you propose to weld the firehole ring to the inner firebox?, looks a tricky one to me.

Jasonb, you are absolutely right, it will be tricky and will take a lot of patience on my part. I will have to leave the coffee alone prior to welding the inside. :big: A bevel will be ground on each mating piece generating a "V" at the weld joint. The surfaces will be flush with each other. But having the "V" will give me a good visual to follow through the welding process. The TIG torch has a long hollow top to it to accomadate a 6" long piece of tungsten. That piece can be replaced by a small cap and then only a 2" long piece of tungsten can be used. This allows for the torch head to be shortened a great deal and allows for access into the proverbial "Tight Places". I did a little practice with the torch head inside the firebox and I feel it will be a doable process. I have been in tighter situations at the college where I use to work where we made a lot of high vacume chambers out of stainless steel.

I will post some pictures shortly and give an update on the process.
kvom said:
How about a closer look at the tailstock for the dividing head. Looks interesting.

Looks like a couple of 1-2-3 blocks, vee block, clamp and a bit of rod to me
You are exactly right ! The rod is a 0.250" diameter hardened steel dowel pin that has a point ground on the end. It was then inserted in the center hole of the aluminum block. Sorry, but I tore the setup down before reading your request for more pictures. Jason, I find setups almost as challenging as the actual machining process. Sometimes it can take hours to make a setup and then only minutes to make the cut. It is a lot like Thanksgiving dinner. It takes all morning and early afternoon to prepare the feast and in less than 20 minutes it has all been consumed :big:

Thank you for your interest and comments. I truly am enjoying looking at your Fowler Engine :bow:
Well the deed has been done. The firebox ring is in and welded. YEH !

Picture #1 is a view of the interior after welding.

Picture #2 is view of the outside just prior to doing the root weld.

Picture #3 is the boiler standing tall and proud and anxious to make steam.

Next is installing the steam stand pipe inside the boiler. Weld the top tube sheet in place. Prep the flue tubes and install them. Make the fire box door, hinges and latch. Then maker a lot of little MTP plugs for the hydro test.



Well the top tube sheet is welded to the boiler shell and I have started to work up the copper flue tubes. A brief recap; I am drilling out the copper tubing that was sent to me to 0.250" diameter and then reaming 1-1/2" into each end with a Letter"F" (0.257") reamer. This makes it just the right diameter for the tube roller I have.

Let me pass on a couple of machining techniques for you. When drilling into an existing hole, Chamfer the hole first so the drill does not have a sharp edge to start on. This will eliminate the chatter and give a truer hole. The same thing applies to reaming the hole. Generate a chamfer for the reamer to start against. I bring the reamer right up to the tube and apply a little pressure via the tail stock hand wheel. Then I turn on the the spindle and the reamer starts to cut immediately. This eliminates the chatter that is associated with a multi-edge cutting tools.

Picture #1 shows the tube roller being inserted into the copper flue tube for the rolling process.

Picture #2 shows the tube roller inserted all the way to its adjustable stop. I use a 5/16" 12 point socket with a "T" handle to rotate the tapered shaft that expands the rollers out inside the flue tube. As you turn the "T" handle clock wise it feeds itself into the tube roller main body and thus expanding rollers that in turn expands the tube into the hole of the tube sheet. Rotate the "T" handle counter clock wise and the tapered shaft retracts allowing the tube roller to be removed from the flue tube. I will not know what kind of job I have done until I do a hydro test. It should be very interesting to say the least.

Picture #3 shows the top tube sheet with four flue tubes in place and rolled. YEH! Now I only have 38 more to go.



Hi Larry,
Nice work you should be ready for a hydro soon. I am glad to know the drill and ream the end worked for that tube roller as I have one just like it in the drawer.