Another Red One. AKA 1/2 Scale Gade Build

[Jasonb]

The same source that supplied the Monitor that I built last winter also came up with a set of castings for a half scale model of a 1 1/2HP Gade which was designed by Robert Campbell.

As you can see by the tape measure its quite a large model with the majority of castings in a very nice grey iron though the small governor bits and the crankshaft are in SG which does not crack like grey iron can. The carb and conrod are bronze, piston and silencer halves aluminium and there is also a galvanized splash guard and tinplate fuel tank.



Also included in the kit were a whole load of goodies: gears, springs, piston rings, gib head keys, fixings, etc.



Another bonus was the cart kit from Iowa Miniature Engines which had just about everything needed for the cart except paint



The wheels have the spokes cast into the hubs just like they would have been on the full size.



The front axle bolster is also cast around the axle. All metal has been shot blasted so the castings are nice and clean the only slight downside is the axles will act like files inside the aluminium hubs but its not as though its going to get pulled about a lot.



Starting with the main base casting I spent some time packing it up on the marking out table until it sat as square as possible. It was then transfered to the mill and the same packers and feeler gauges used to set it up and a light skim taken off the bearing housings and top of the cylinder mountings making a note of the difference in height between the two surfaces. There was a small amount of chilling on the tops of the cylinder mounting which you should be able to see as the darker area around the edge, the insert tool took this hard material in its stride.



Now that I had a couple of decent flat surfaces the base was mounted upside down and the bearing housings packed up to the height I had recorded from the previous machining. This gave me a good solid setup to machine the base flat and also just tidy up the 4 edges so I had something to use as a reference surface for future setups. The 4 mounting holes were drilled and a pointed tool used to scribe a centre line for good measure.



The base was then put to one side as I wanted to have the bearing caps ready before doing more work on it. The cap was held in the vice and one side cleaned up, note the two strips of aluminium packing which gives a better grip than having the rough texture of the cast surface up against the hardened vice jaws.



The other side was then treated the same which gave two machined surfaces to hold while the mating surface was milled flat.



With that surface resting on parallels the two stud holes were drilled and spot faced. I also drilled and tapped for the greasers.



I could now go back to the base and machine the bearing block faces to the correct height, tap for the studs and then using temporary bolts (and a lot of washers) fit the caps in place. The sides of the housings were then machined to the correct width ready for boring the bearing holes which I will cover next time.



J

[Jo]

Is this same man who the other day was saying he didn't like castings and preferred to scratch build all his engines 

Jo

[b.lindsey]

Nice start Jason and looks like a very complete kit as well!!  Will be watching with interest.

Bill

[fumopuc]

Hi Jo, it is Jason, the engine is already finished. Only the thread has just started.

[Jasonb]

"Is this same man who the other day was saying he didn't like castings and preferred to scratch build all HIS engines."

I'll stand by that statement, you know what I mean by the bold type

It was enjoyable to build but did not really offer much of a challenge so that is why I'm moving away from casting kits, not to say I won't be using the odd casting and maybe even one from a 3D printed pattern, watch this space

[Don1966]

Ok Jason I'll be watching so bring it on....................

Don

[Jo]

It was enjoyable to build but did not really offer much of a challenge so that is why I'm moving away from casting kits, not to say I won't be using the odd casting and maybe even one from a 3D printed pattern, watch this space

Where you have done so many similar Hit and Miss engines I can see why another would not offer much of a challenge 


  I have just realised in a moment of weakness you brought another casting set for yet another horizontal hit and miss engine    What were you thinking when you brought it  , how could you ever love it and show it the attention it deserves, if you don't think they offer any challenge to make   


But you will be pleased to hear that I run a home for unloved model engine castings and I am willing to refund your adoption fee and to provide your orphan castings a loving home where no one will ever utter the heresy of suggesting that castings offer no challenge to the model engine builder  .

Jo

[Jasonb]

Maybe I could swap it for one of those all very similar Westbury casting sets you have

I've not ruled out casting sets or Hit and Miss engines ( there are still a few desirable ones out there) but as I said I can see myself moving more towards fabricated engines and that is what I see on my immediate "to do" list. Most of those will also be to my own design rather than just enlarging and detailing existing designs so yet more of a challenge to keep me on my toes which makes that dance at the end even more rewarding

Being a bit smaller than my usual size the Hired Man offers a practical way to make a drag saw or pumpjack from scratch without ending up with a massive model that is a pain to move and store. I'm also collecting my references so that I can make all the small parts look like the original castings and forgings not the simplified fabrications shown on the plans

J

[Jo]

I think you need something challenging I have a few bits of an orphaned unstarted Sealion that would stretch you skills, if you were up for it 

You know where to deliver my Little brother's big brother so I can do my tandem build 

Jo

[Jasonb]

Right, Back to the build.

I usually bore my bearing housings by clamping the base casting down to the lathe cross slide but in this case the centre line was too high. As an alternative I mounted two angle plates along the rear of the cross slide and clocked then true to the lathe axis then with the end of the casting stood on a suitable height parallel clamped its bottom face to the angle plates and used a wobbler to locate where the hole was to go.



I then spot drilled followed by a 1/4" stub drill to get as true a start as possible and then when the flutes ran out changed to a standard jobber length 1/4" bit to pilot drill the first side. Then using a 4" long ctr drill started the hole on the opposite housing and then drilled the rest of the way with a long series 1/4" drill. The brass tube you can see in the tailstock chuck was used to apply additional pressure to the casting as the carrage was fed along to help stop any risk of the casting twisting on the cross slide.



The hole was then enlarged in sevaral stages with various drills until I could pass a 18.5mm boring bar through and that was used to bring the holes true and to size. I opted to bore 20mm rather than 3/4" which was on the drawing as it gave a bit more room for the bar, allowed me to use a 3/4" blacksmiths drill to open things up and the supplied 3/4" OD Oilite bushes were too short for my liking anyway.



Now that I had a bored hole to measure from the casting was set up on the mill and the cylinder mounting face machined and the 4 mounting holes drilled and tapped 1/4" BSF. There are a few more things to do to this casting but I will leave them for a moment until some other parts are complete.



One good thing about this engine is its air cooled which saves having to worry about machining a separate liner and getting it a good press fit into the cylinder. The down side is that the two halves of the mould had moved slightly which meant all the cooling fins had a nasty step where the parting line was. You can get an idea of the offset as one half of the mounting face is machined flat yet the other has barely been touched buy the tool. Luckily there is a good 1/8" machining allowance on all the surfaces so I could just get the correct O/A length.



With the end faced I started to bore out the casting extending the carbide tipped tool in stages to keep it as rigid as possible so a decent depth of cut could be taken.



5 1/2" to the bottom



With most of the waste removed I switched to a 1" dia boring bar with HSS toolbit for the final cuts. This bar has to be clamped to the original 4-way toolpost that came with my lathe but works well and is nice and rigid.



The final job at this setting was to add a small chamfer to help whith getting the piston rings into the cylinder.



It was then a simple job to reverse the cylinder to machine the head mounting surface and get the correct overall length



Over to the mill now and the mounting flange was squared up and the matching four 1/4" holes drilled for the studs.



The Gade is a bit different to most IC engines in that it has two exhausts, the main one is at the bottom of the cylinder and lets out any gas that is still expanding from the combustion process. The second is a conventional one in the head operated by a normal valve that just lets out any remaining gas as the piston rises back towards the head. It was supposed to let the engine run cooler and more efficiently.

The main exhuset comes out the side of the cylinder and this was just faced off square and tapped 3/8" BSP, for those not familiar with pipe threads, they are sized by the bore of teh pipe so a 3/8" pipe thread is actually 0.656" OD.



A quick 90degree rotation and the hole for the drip oiler was drilled & tapped.



I'll leave the cylinder head fixings until the head is machined just incase they need to be moved about.

J

[Don1966]

Now setting that casting up on the cross slide like you did is too cool.  Still with you.................

 

Don

[fumopuc]

Hi Jason, watching and learning from your set up.

[Graham G]

Hi Jason, I too am looking and learning from your setups.
Cheers
Graham

[Dave Otto]

Hi Jason

Enjoying your progress of the engine that is apparently already finished and running .

Gades are nice runners.

Dave

[Jasonb]

The crankshaft comes as a substantial SG Iron casting almost 14" long



The first thing I did was mill the sides of the webs to give me a flat plane to work with and also skim the two ends. Using the mill table as a surface plate I laid it flat down and marked the ctr line, then clamped the casting to an angle plate and put on lines at 90 degrees just to act as a guild.



The crank was a bit to long to fit under the mill with a drill or collet chuck so I knocked up an adaptor to hold a ctr drill that could be held in a MT3 taper collet.



I trued up an angle plate and clamped the flat webs to that, picked up my lines and then used the DRO to position the three ctr holes and repeated for the other end. By keeping the same side of the webs against the angle plate I could ensure that both sets of 3 holes were perfectly in line so no risk of a twisted crank.



Over to the lathe and I took a couple of roughing cuts off the main shaft to get the mass down and reduce any imbalance to a minimum. Then using the middle of the three ctr holes radiused the ends of the webs.



I have a tool that takes the 55deg rhomboid shaped tips that is reversible so I get a left and right hand tool in one and used this to machine down the inner face of the webs.



[youtube1]https://youtu.be/18pocye3leM[/youtube1]

Its a nice rigid tool but a bit to wide to remove all the metal in the middle.



So had to use a parting tool for the last cuts, I keep one of the 2mm wide tips that has had the middle ground away with a dremel as this reduces chatter and leaves a reasonable fininsh as the tool is wound from side to side taking fine cuts.



A bit of final finishing and it look reasonable to me.



I was getting a bit of chatter on the  main shafts so resorted to holding one end in a collet while I took the other down to about 0.010" ovesize and also did the outer edge of the webs. Final cuts were between ctrs with a HSS tool rather than the indexables.



With the crankshaft finished I could start to make some of the bits that fit onto it.

The pully is quite simple just a crowned outer and a 5/8" hole bored to a nice sliding fit on the shaft.



I was able to hold the flywheels in the 4-jaw and get the inner face of the rim as true as possible then turn the OD to size.



[youtube1]https://youtu.be/9rnE5jZwPR4[/youtube1]

Followed by the side and then facing and boring the hub.



To machine the other side I use a dti on the rim and another on the back face until it was all within 1/2 a thou.



There are a couple of small areas that were a bit low but they can be filled later. This is the governor side flywheel so that also needed a register for the governor weight bracket.



Finally 3 drilled and spotfaced holes to take the bracket bolts.