Constructing the Josslin Hudson

Where users can chronicle their builds. Start one thread and continue to add on to it.

Moderators: Harold_V, WJH, hwboivin3

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: A Peek At The Josslin Hudson Lead Truck

Post by Carrdo » Wed Aug 25, 2010 7:05 pm

Moving on to the remaining frame pieces shown in the photos, the only real concern is to have them all the exact same width (length) as this is required to have a square frame upon assembly. What ever works for you use it here.

I tend to rough out all pieces to 0.005" oversize then finish a part to length and then follow with all of the remaining parts. I can do this as the mill's vise has been set square and the base of the vise and the vise jaws are pristine.
Attachments
510 Drilling and Tapping Swing Link Frame Piece Hanger Pins.jpg
509 Machining Equalizer Cutaways on Swing Link Frame Pieces.jpg

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: A Peek At The Josslin Hudson Lead Truck

Post by Carrdo » Wed Aug 25, 2010 7:59 pm

All of the finished basic frame assembly pieces including the brake lugs together with an extra partially machined axlebox.

I am tending towards silver soldering all of the components but may end up bolting on the brake lugs as how does one silver solder so many pieces in such close proximity one to the other without risking melting the previously soldered work.

If I proceed with silver soldering, I would use strip silver solder for a job like this (don't have any at the moment), pin everything first to maintain it in alignment (as with the frame filling pieces - lots of work there and much more here!) and use heavy 1-1/8" square CR or HR push fit extended length steel axles to keep the frame openings in perfect alignment under silver soldering conditions when the entire frame assembly will be red hot.

Also have to build a welded steel angle and firebrick silver soldering (and boiler silver soldering) table which will be used in conjunction with the 2.5" diameter propane fired flame thrower bought several years ago as work like this can't be done indoors. The weed eater flame thrower will be used to preheat the whole mess which will be placed in a firebrick "pit".

Alternatively, could have the assembly all TIG welded by a specialty welder (would still pin everything in advance). Some of the fine detail would be lost on the delicate parts and there is a greater risk of distortion but it would be quick (time saver) and a lower overall cost.

Decisions, decisions.
Attachments
511 Lead Truck Finished Frame Components.jpg

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: A Peek At The Josslin Hudson Lead Truck

Post by Carrdo » Mon Sep 27, 2010 4:06 pm

Next, the actual pinning of a pair of brake lugs and spacer to a side frame.

This caused a lot of pondering on my part on what to do here as the brake lugs at this point are mostly curved with very little of anything to hold on to never mind securely. And they have to be positioned correctly.

The simple and the obvious are the way to go but it took some time to see the light.

Position and glue a brake lug to a side frame initially. Then drill the brake lug flared ends for the positioning pins when the glue has set, then knock the brake lugs off, remove the dried glue from the parts and pin everything back together again ready for silver soldering.

There are a few points to be aware of. I used 0.041" dia. hard wire for the locating pins. Previous experimentation had shown that a #59 drill was the correct drill to use with this wire diameter to have the pins a nice push fit in the parts without slop.

The pin holes were drilled into the curved ends of the brake lugs. Drilling into curved surfaces needs a sharp center drill to start the hole without wandering and the shortest drill extension possible. Also, you need to use your best drill chuck to eliminate any orbiting motion of the drill(s).

The second photo, where it is hard to see the details, was the setup used to position a lug for glueing. Since I do everything mechanically, a spacer piece exactly 1/2 the width of an axlebox opening was set in the RH axlebox opening as seen in the photo. Then a 6" graduated scale having a stop set with the aid of an eye loupe the distance from the centerline of the axlebox opening to the face of a brake lug as shown in the photo.

The side frame itself was set on parallels in the vise and an adjustable parallel was set up inside the center opening on which the ends of the brake lugs rested to keep them level and stop from tipping over (which they wanted to do). As well, there is a steel rear aligning piece set against the top rail (depressed center) of the side frame to keep the brake lug square with the top rail of the side frame. If you study the photo, all of the described elements can be seem.

Positioning is important as your eye can see the slightest misalignment here.

The third photo shows the results. I think it came out well.
Attachments
514 Brake Lugs and Spacer Pinned to a Side Frame.jpg
513 Positioning a Brake Lug on a Side Frame.jpg
512 Drilling a Brake Lug for the Mounting Pins.jpg

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: A Peek At The Josslin Hudson Lead Truck

Post by Carrdo » Wed Sep 29, 2010 11:31 pm

Up next is to assemble all of the frame pieces temporarily into a complete frame assembly. To do this, one has first to make close fitting extended length dummy axle pieces to keep the frame axlebox openings in complete alignment. Then the remaining pieces are assembled. Fiddle, fiddle, as all of these pieces have a mind of their own.

The temporary assembly will show all of your previous good work (or not) as the completed assembly must be square, parallel, level and a true rectangular box.

I have now decided to make the basic frame assembly itself a bolted unit (as was done with the first Hudson lead truck made a few years ago and only silver solder the brake lug assemblies to the side frames. This method works well and the fasteners will not seen as they will be hidden behind the remaining lead truck components that are yet to be made.

As noted previously, out of caution, to have a complete silver soldered assembly, the frame axlebox openings should have been left rough machined (with a rough temporary tie bar used to keep the openings square) and finished only after the frame had been totally silver soldered (which has its own holding problems as discussed previously).

I did silver solder the basic frame assembly, with finished frame axlebox openings on the second Hudson lead truck made and there was no distortion or resultant misalignment (extended heavy dummy axle pieces and the bottom tie bar were used to keep the frame axlebox openings square and in alignment) but this lead truck was made without the brake lugs. Silver soldering these assemblies will be a good test for my new 2.5" dia. propane flame thrower and ribbon silver solder which another TSME member generously gave me.

Having come this far, with all of the work involved to date, I will stick with the oft quoted "discretion is the better part of valour".
Attachments
517 Complete Frame Temporarily Assembled.jpg
516 Finished Frame Pieces Ready for Assembly .jpg

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: A Peek At The Josslin Hudson Lead Truck

Post by Carrdo » Mon Oct 04, 2010 1:41 pm

Everything now has to be taken apart again for the next setup to drill and tap the main frame pieces to form a complete assembly.

This involves a rather complicated setup and one which could not be done this way with a cast frame or if the originally produced reference side frame surfaces did not still exist.

The first job was to make up a sketch of all of the locations of the cross members in relation to the still existing side frame reference surfaces and the axlebox frame cutouts. Then accurate spacer pieces were made to the necessary size in two directions for locating the end beams.

The entire setup relies on being able to rest and align the side frames (level and square) against a suitably sized angle plate which has been set square on the table of the mill. See the first photo for the partial setup on how this is done. One can see here the two spacer pieces aligning an end beam, one (spacer) rests against the angle plate and the other against the extended dummy axle. The two vertical spacers in the middle are to align the swing link brackets to the frame.

Care needs to be taken to have the side frames in their correct orientation as it is all to easy to have one or both side frames back to front (one to the other) or the wrong side up or down. Another reason for marking them.

Next the position of an end beam has to be carefully laid out on the outer side of the second side frame. The second photo shows the setup for scribing the most difficult part - the location of the vertical sides of the side beam.

The third photo shows the full setup with both side frames now in place and clamped (with the end beam clamped as well). If everything has been made square and parallel, the clamped end beam now has to be located directly under the scribed rectangle on the outer surface of the upper side frame. Check again before drilling that all is aligned and square as one gets only one shot at this.

One can now proceed to drill and tap through the upper side frame with confidence. Since drilling and tapping is not interesting, will only show the finished result. There are a total of 8 bolts to be installed for the end beams and 12 bolts for the swing link brackets.

Likely, there is a more simple way of doing this but as I have done it this way before and it worked, will stick with the devil I know.
Attachments
521 Full Setup Used to Align and Locate End Beam on Inner Face of Side Frame.jpg
520 Setup Used to Scribe Vertical Edges of End Beam on Outer Face of Side Frame.jpg
518 Partial Setup Used to Align and Locate End Beam on Inner Face of Side Frame.jpg

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: A Peek At The Josslin Hudson Lead Truck

Post by Carrdo » Wed Oct 06, 2010 5:37 pm

One side frame is now bolted. Had the usual problems of reaching into tight corners (need to use extra long center drills, etc.) and broke a drill in the process.

The center of the side frame will be roughed up more to give the silver solder something to hold on to when soldering the brake lugs and the central countersunk cap screws will be permanently buried under the brake lug assemblies.
Attachments
523 One Side Frame Bolted.jpg

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: A Peek At The Josslin Hudson Lead Truck

Post by Carrdo » Thu Oct 14, 2010 7:31 pm

The basic frame assembly after months of work. Still have to silver solder the brake lugs to the side frames.

Was it worth it?

It looks good, and if it works as well as it looks, I will be very happy. :)
Attachments
524 The Basic Frame Assembly.jpg

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: Constructing the Josslin Hudson Part 54 (Update)

Post by Carrdo » Thu Nov 04, 2010 1:04 pm

The next operation was to machine the leaf spring base blocks. As they are simply rectangular pieces of HR steel with a hole drilled in the center part way through, they require no further description.

After this, the matched axleboxes were set up individually in the vise of the mill and the leaf spring base block seating on number 1 axlebox was machined to its final width and depth in the axlebox saddle arm. At the same time the top slot in the axlebox body was milled to its final width and depth and the saddle arms were machined internally to their final width so they could pass through and clear the top rail of the main frame. All of this was done first with undersized sharpened end mills progressively increasing in size to the finished widths. In some cases extra long end mills were needed when machining the top slot down between the saddle arms.

The 9D material continued to exhibit its nasty effects on my end mills by producing rapid corner wear on any cutter that was not freshly sharpened.

Next, number 1 axlebox was spotted on one face with layout dye then turned 90 degrees, then rotated back 180 degrees to bring the two main frame slots sequentially into position for finish milling. Again, undersized end mills were employed to progressively increase the slot width to finished size and depth. Not much material remained to be removed as these slots had been milled close to finished size previously.

For this critical operation, after a cut was taken on one slot, the axlebox was removed from the vise, any and all burrs eliminated, the axlebox was then rotated 180 degrees (the layout dye ensuring the same side of the axlebox always faced forward) and the exact same cut made on the second slot. The main frame side slots were thus incrementally widened and deepened to their finished size and width in tandem. I could do this and have total confidence the slots would be square, straight, on size. and totally parallel and laying in the same plane as the axleboxes have previously been finished as matched pairs straight and square in all directions. As well, my vise jaws and vise jaw floor were previously finished and indicated square and level. It is all prep. work. This method also insures that all of the finishing work described above on the saddle arms and top slot would also end up square with and be in the same plane as the side slots.

If your vise is not up to this, then employ a good quality angle plate and parallels. The above described procedure will work just as well here although one has to employ clamps to clamp the axlebox against the angle plate.

Again, the 9D showed its nasty side when taking the final slot cuts as I had to re-square and sharpen the end of my end mills to end up with truly square cornered slots.

The result was I ended up with a tap fit of the axlebox in the frame opening on all of the slot faces. I always fit my axleboxes this way on first fitting on the theory it is always easier to remove metal than to put it back and while the final width and depth of the axlebox main frame slots has been achieved, the final FORM hasn't. There are more tricks to come.

For the first fitting of the axlebox to the main frame itself, one has to be aware of a few issues. With HR steel, it always comes with a thin layer of mill scale (as seen in the last photo).

For 3/8" thick HR steel which the main frames are, the micrometer size of 0.375" can suddenly drop to 0.368" or less when the mill scale is removed or starts to flake off. As well, the thickness of the bare steel at the top rail compared to the thickness of the bare steel at the pedestal jaws can vary by up to 0.003" or more.

To make the unmachined side surfaces of the main frame more or less uniform thickness, they were spotted with layout dye in the area of the axlebox opening and the axlebox tapped on as far as it would go. Where the dye was rubbed off a rifler file was used to remove a little bit of metal and the process was then repeated.

The above is much like scraping to a flat surface but much cruder and faster.

So for first fitting, the mill scale was first removed with emery paper and then the bare metal was "scraped" down until a uniform tap fit was achieved along the entire vertical travel of the axlebox. This meant the number 1 finished axlebox slot width ended up being 0.368" (which was the thinnest frame thickness in the area of axlebox number 1) in my case.

This means that while the main frame axlebox openings and axleboxes themselves are fine machined, each axlebox has to be individually fitted to a particular frame opening. The axleboxes will be close fitted but not interchangeable as per full size practice. This means each axlebox needs to be individually marked as to its location.

For final fitting (once the final slot form is achieved), if there are still binds anywhere or if the axleboxes do not "rock and roll" as planned or as much as planned, a little bit of coarse valve grinding compound will be used to final lap the sliding surfaces. One wants to leave a "bit" of a rough steel frame surface for oil and or grease to adhere to.
Attachments
317 First Fitting of an Axlebox.jpg
316 Machined Axlebox Saddle Arm for Leaf Spring Base Block.jpg
315 Leaf Springs Base Blocks.jpg

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: Constructing the Josslin Hudson Part 54 (Update)

Post by Carrdo » Sat Nov 06, 2010 4:22 pm

Some further photos showing fitting of axleboxes to the main frames.
Attachments
322 Leading Drivers Axleboxes Fitted.jpg
320 Finished Frame Spotting Around Axlebox Opening.jpg
319 Spotting Frame to Fit an Axlebox.jpg

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: Constructing the Josslin Hudson Part 54 (Update)

Post by Carrdo » Tue Nov 16, 2010 10:18 pm

Moving right along at less than a snail's pace, the next operation was the fitting of a leaf spring assembly to an axlebox.

This involved two deep drilling operations through the axlebox saddle arms and the leaf spring base block lengthwise. At this point the depth of the through holes were 3/4" long and only 3/32" in diameter. Another operation where everything is against you from the beginning.

See the first photo for the setup used.

Initially, layout the location, horizontally and vertically, of the holes to be drilled carefully on one face of a saddle arm as there is little room for any error. I used my vernier height gauge and surface plate for this. Again, having the axlebox machined all square pays dividends here.

Then with the leaf spring base block centered between the saddle arms and bedded square on the ledges milled out in the saddle arms (remove all burs) locate, center drill, under size drill and finally drill through 3/32" for the attaching bolts or studs as per the setup shown.

But there is much more too it than that.

9D no more likes twist drills than it does end mills. So your drill has to be new or freshly sharpened and one must drill in short stages otherwise the 9D will grab the drill. Also, with these small drills, as one drills deeper, the collection and evacuation of chips becomes more and more of a problem if you want the drill to drill straight and square and not have the drill jam. Here you are drilling through two different materials so one has to be extra careful especially at the transition points.

It is hard to see in the first photo but I employ a long needle magnetized on its point to pull all of the remaining chips from any small deep holes for all stages of the drilling. Also, these holes were step drilled in stages to give more clearance for the chips and to relieve the drilling pressure on the first or pilot drill.

Very tedious and time consuming but if you want the hole to be straight and come out on the other side where you want it to be.

Even so, the holes ended up being very tight on the pins. And on one hole I forgot to tighten the knee on the mill so the hole is a wee bit cocked. Lose your concentration for a moment and..

The second photo shows all of the parts mated. Will need to put a 3/32" reamer through to have the final fit I want. Another tool which I don't have at the moment. So while I slowly go broke buying tools which I thought I didn't need...

Don't know whether I have described previously how to make the leaf spring assemblies as they were made a couple of years ago. That was another "more than a bit of fun exercise". And, as Richard says, I probably found the most difficult way possible to do it but will describe my methods when the axleboxes are finally finished.

Even at this stage, there are still five more machining operations left to do on the axleboxes not including fitting them to the main frames.
Attachments
324 First Fitting of a Leaf Spring Assembly to an Axlebox.jpg
323 Setup for Deep Drilling Through Axlebox Saddle Arms and Leaf Spring Base Block.jpg

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: Constructing the Josslin Hudson Part 54 (Update)

Post by Carrdo » Tue Nov 23, 2010 8:28 pm

Moving on. An entire pile of end mills are in for sharpening so I can finish the last two axleboxes.
Attachments
325 Three Leaf Spring Assemblies Fitted.jpg

User avatar
Carrdo
Posts: 959
Joined: Thu Mar 06, 2003 2:20 pm
Location: Toronto, Canada

Re: Constructing the Josslin Hudson Part 54 (Update)

Post by Carrdo » Fri Nov 26, 2010 6:57 pm

Four of the six axleboxes are now initially fitted. I do admit to using a bit of lapping compound to get from a tapping to a very good slide fit. Lots of grit and mess. It is hard on the fingers with the axlebox push/pull up and down in the frame openings with all of those hard edges just waiting to snag you.

Lots of work remaining but slowly we are getting there.
Attachments
327 Four Axleboxes Fitted.jpg

Post Reply