The Workshop Progress thread 2018

[David TaylorParticipant @davidtaylor63402]

Really nice Brian – I can well imagine the stress of making that appear from a solid block but you've done it!

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Brian O'Connor on 18/09/2018 15:38:52:

Just finished the Cam Gear Bracket for my Star hit&miss engine. It started out as a 3in x 3in x 1.5in block of cast iron. It now weighs less than 10% of its original weight. Bucket of swarf, anyone?

.

I've only just seen this, Brian

You have my great admiration.

MichaelG.

[Ron LadenParticipant @ronladen17547]

Posted by Brian O'Connor on 18/09/2018 15:38:52:

Just finished the Cam Gear Bracket for my Star hit&miss engine. It started out as a 3in x 3in x 1.5in block of cast iron. It now weighs less than 10% of its original weight. Bucket of swarf, anyone?

B

Superb Brian, I can imagine how nerve racking that must have been, completing a number of stages and realising that the slightest mistake on the next stage would undo all that went before.

Excellent.

[JasonBModerator @jasonb]

I've done a few more bit sfor teh IF Allman engine this week.

The exhaust valve casting was machines plus a valve and spring collet to go with it as well as a stubby exhaust pipe

I was a bit worried that the cylinder liner casting would not be usable as the mould halves had moved at least 1/16" plus the core was off ctr but it just cleaned up OK. Luckily the casting was over long and I only need it upto the pen mark.

The fixed steady stopped it flailing about while it was bored, the last few finish cuts were done with a CCMT tip as I find there don't get pushed off the surface as much so you get a straighter bore which is 1.5" dia x 4.375" long.

The cast iron "Hemi" cylinder head was rather chilled around the edge but the good old CCMT tips cut that off in short ribbons.

I decided it was not worth making the timing gears for which I would have had to buy a couple of cutters, these two 1.5MOD gears cost less than £20 delivered from Beltingonline and there is enough for two engines even allowing for a wonky saw cut.

Edited By JasonB on 23/09/2018 18:49:41

[mechman48Participant @mechman48]

Another small step … soldered cylinders to blocks, the polished one was soldered using solder paste as a look see set up, it worked. the second was silver soldered, then pickled to see how the pickling process worked to clean up the soldered area. I mixed up a small amount of citric acid granules, about a dessert poon into approx' a glass tumbler size plastic box full of water until dissolved. The cylinder assembly was left in the solution for about 1/2 an hour & showed a pretty rapid action, I left it for an hour & it came up really cleaned. I obviously had made up a concentrated amount of citric acid as I didn't really measure out any sort of ratio – granule grams to liquid mils, a suck it & see scenario. If any one has small amount measurement table rather than a full litre mix that they have used & noted I would appreciate a copy / ref. …I could work back over – 40grm packet granules to 1 litre water – 20 gram to 1/2 ltr etc. but asking just on the off chance…

One polished, one pickled …

George.

Edited By mechman48 on 27/09/2018 16:30:38

[Jim NicParticipant @jimnic]

For my pickle, George, I just start with the amount of water I need and then keep adding citric acid crystals until the solution is saturated. The initial excess crystals fall to the bottom of the container and dissolve over a couple of days. It seems to work OK, as did yours.

When you say you used solder paste, was that soft solder paste or a form of silver solder?

Jim

[mechman48Participant @mechman48]

Hi Jim

The solder paste is a tub that I'd bought from a supplier at the last Harrogate model exhib' before it moved to Doncaster so that would be about 3 years ago, can't remember who it was so no name comes to mind. From the use I've had so far it is good for small general soldering but I doubt it would hold up to some large work where silver solder would be the preferred method…?

George.

p.s. Excuse the watermark on pic of propriety named item, spotted after posting; usual disclaimer applies

Edited By mechman48 on 28/09/2018 11:43:56

[geoff walker 1Participant @geoffwalker1]

Hi George,

I notice the pistons are bevelled. Never seen that before.

Presumably so that the piston will travel further and not cover the port hole.

….and you have that vee cut to aid compression.

Nice work Geoff

[Jim NicParticipant @jimnic]

Hi George

Thanks for the reply. I have seen low temperature solder paste before but I was hoping you had found silver solder paste.

For similar applications I have used silver solder foil supplied by CuP Alloys which is placed, with some flux, between larger surface to be joined before heating. It works well but is expensive.

Jim

[mechman48Participant @mechman48]

Hi Geoff

In essence… yes, plus that's the way the drawing shows, so I've not deviated much, if any

George.

[JasonBModerator @jasonb]

Jim, CuP do SS paste if you are looking for it

[Jim NicParticipant @jimnic]

Thanks Jason, I hadn't spotted that. Pricey but probably good for a couple of small eccentric sheaves I have to solder up so I'll get some at the Midlands Show and give it a go.

Jim

[mechman48Participant @mechman48]

A little more along the path towards the Boxer oscillator…

The flat portion of the frame ( bottom ) will be bent to right angle prior to the port blocks being soldered to the frame… just in case 'I miscalculate the bend' …

George.

[Ian McVickersParticipant @ianmcvickers56553]

Not sure if this should be in this thread but anyway here goes. I was fed up trying to get enough space to put things on when working on either the mill or the lathe so decide that a table on wheels was the way to go. This way I can move between machines with the bits in working with.

Now I can carry on with the new tool rests for my grinders.

[David TaylorParticipant @davidtaylor63402]

Got the rear brakes on. The pullrods were done on the CNC mill and I also used it to do one particular cut on the brakeshoes.

Now onto make the handbrake parts and dummy airbrake components.

Regards, David.

[David TaylorParticipant @davidtaylor63402]

Made a dummy brake cylinder. Nothing here you all haven't done a 1000 times before but an enjoyable, non-precise, non-working, decorative shiny thing.

David.

[Jim NicParticipant @jimnic]

Not a lot to show on the Overcrank since my last post on 12 Sep but here is a "family shot" of the components of the largely completed cylinder block.

And the assembled bits.

I'm not quite sure how best to proceed so to give me some thinking time I will make the aluminium sheet base and then probably the 3 main bearing supports.

Jim

[JasonBModerator @jasonb]

Looking good Jim.

[mechman48Participant @mechman48]

… verrrrrry nice Jim.

Geo.

[Neil WyattModerator @neilwyatt]

Lot's of nice work, folks.

Neil

[MWParticipant @mw27036]

Hi again,

Loving Octobers issue with the mike cox tailstock conversion, great work and the funny prize winner for the AAA battery conversion on a digi-caliper, nice.

I'm restoring an enormous 6" bench vise that i picked up and took home from the market for a bargain, using it to replace my tidly 2-3" vise thereabouts. I will post some progress pictures along with a before and after shot. It's got a bit of everything to do, stripping old paint, wonky jaw to fix up on the mill etc.. I might make a brass or nylon faced set of jaws as well.

The jaw had been machined before me, but was at a wonky angle so i needed to set it straight with an endmill, none of my cheapo HSS would touch it, not even carbide, i needed to use my ultra speciale NACO coated carbide tool which finished the job. Creeped up on the cut for a nice finish and took the opportunity to square off the ends, shame the jaw recess on casting itself isn't flat either, but not alot i can do about that. So i'd definitely recommend those blue coated carbide choppers.

It has a very big 6 x 6" anvil on the back and i want to take the dents off and polish the surface, was slogging it with rough ali-oxide paper, getting nowhere, then i remembered i bought a corded milwaukee angle grinder, and remembered you could skim the face with the edge of a metal cutting disc. Boy those things can cut metal.

The journey continues!

Michael W

[JasonBModerator @jasonb]

I got the burner and base for my wee Robbie finished off so thought a couple of pictures were in order, seems like blue is the popular choice for these engines.

I did try it with Mamod fuel tabs without the base and it ran OK on them going nearly the full 10min burn time before slowing as the engien got a bit hot, I was nor running any cooling water. However the style of base I made would not work with the tablets as there was not enough air and the flame soon went out.

So a change of firing method was needed, I settled on a modified camping gas stove as this draws it's air from outside or in this case up from under the raised display base and also offers more control over the flame not to mention less of a smell.

As seems to be the usual case the engine did not want to run once it was all back on the base, I eventually traces this to the flywheel being a bit close to the bearing and rubbing but not before I had tried it with a bit more heat than I should which resulted in a scorched base and one of the joints opening up

Anyway the base repairs can wait, here is the video. Ruler make sit look a bit shorter than it is but still only 4 1/2 " from back of cylinder to front of chimney.

J

[Neil WyattModerator @neilwyatt]

Is that from the Polly castings?

Neil

[JasonBModerator @jasonb]

No all carved from solid or fabricated except the flywheel which is a Stuart 10 size casting.

Scaled down to 24mm bore from the Alyn half scale drawings with suitable alterations for size and not using castings.

This "naked" shot of it sat on my tailstock shows the bare materials.

Edited By JasonB on 15/10/2018 12:16:24

[Jim NicParticipant @jimnic]

I'm not a fan of hot air engines, but I have to admire the workmanship and appearance of the finished article.

Nice one Jason.

Jim

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