Member postings for JasonB

That sounds a bit low to me, from the photos I would put it closer to 25-28mm maybe check again when you are home.

The tool opening in a holder is 13mm so your tool looks to be about 10mm square. Max height of the bottom of the holder is 17mm but your adjuster is a couple of mm from max so lets say 15mm. so add the 15mm and 10mm and the edge of your tool is 25mm from topslide surface.

As for the nut well it only needs to be hexagonal if you want an extra spanner to loose. Simpler to go with something like you have that is cylindrical with either a fixed tommybar or just a hole for one. You could use the washer that comes with the toolpost then it is just a case of turning one end of some say 25mm bar down until it fits inside the toolpost and threading that end to suit the stud assume M8. Last thing is a hole for the tommy bar.

Not far off what I use on mine, the hole is drilled so I can use the chuck key to tighten the "nut"

the larger 14mm hole in the 111 toolpost gives a decent amount of metal around the M8 thread that you would not get if it had to fit the 10mm hole of the 000 size

Thanks Margret.

Looking at the first photo the tool does not look like it is not yet lined up with the ctr of what you have in the chuck so could do with going up maybe another 2mm. This will put you right at the limit for that height of tool (10mm? ) and anything smaller won't really come upto ctr height without being packed up. So I would be more likely to opt for the 111 toolpost with standard holders so smaller tooling can be used. (hope the bottom ring is screwed on in that photo)

The other advantage of the 111 is the hole in the middle of the toolpost is 14mm which would be better to allow the existing stud to be retained and a shouldered nut made.

BS2790 according to their site which is "Specification for Design and Manufacture of Shell Boilers of Welded Construction"

The Aussie code does specify certain construction methods, material sizes, stay spacing etc which may differ from how a boiler was designed but able to meet the BS requirements. For example I believe the Aussie code is not keen on girder stays but they would be an acceptable method of construction elsewhere.

Edited By JasonB on 31/07/2023 10:24:00

Thanks for those Margret, Both the QCTP you have and the 111 would work with larger tooling but the 000 may not suit the smaller sizes. To check exactly what works could you put something pointe din the lathe chuck or tailstock and take the measurement from that to the top surface of the top slide as below

Also if you could measure the diameter of the threaded portion of your toolpost stud that would help deciding what's the best way to modify that. I suspect it's an M8 thread so should be 8mm or a bit under.

Let me know the two shown

Edited By JasonB on 30/07/2023 20:48:45

Margret, you do not need that flat square block at the bottom of the QCTP, should fit like this

See my comment in the stuck screw thread about heights that matter

Before machining the main crankcase casting of the RLE it is worth getting the bearing caps ready. These are supplied as one so after a skim cut to flatten the bottom and then the ends with the now flat bottom against the vice fixed jaw the casting can be cut in two. Well actually you can cut it into three as there is plenty of length and it's quicker to saw away a waste piece than turn it into chips.

I can see how Graham made the pattern many moons ago simply by gluing a piece of half round timber moulding onto a flat piece and adding a bit of draft around the edges. This gives the profile shown top right in the following photo and if we assume the radius of the "hump" is where the green sharpie mark is then most of the material needs to come off the bottom which combined with a bit of flattening of the hump results in the section shown top left. I went a bit further and used the excess height of the hump to provide enough material to form a boss that can later be drilled and tapped for an oil pot - middle bottom. Clearance hole scan be drilled and spot faced so the caps are ready for when they are needed.



The crankcase was shimmed up on the mill table to get it to sit nice and level and not be distorted by clamping pressure and the facemill used to flatten it's bottom. Now that I had a solid surface it could be set up on the table with some parallel packing below and set to get the best centre line of the casting in line with the mill's X-axis. I started out buy locating the four hold down bolt holes so they sat reasonably central to the cast bosses noting their positions on the DRO before spot facing to give the nuts a good surface to tighten down onto.



Next the vertical face that the cylinder flange mates to was squared up, just taking off the bare minimum at the top and down low enough that the flange clears the step left by machining away the draft angle. I later blended that small step in to leave a smooth fillet where the vertical meets the horizontal as I'm fussy like that..



Moving to the other end of the casting the bearing split line was milled down to the required 41mm above the bottom of the base and the stud holes drilled and tapped M4. You can see in the photo that I'm using a spiral flute tap, I've almost gone over to these exclusively as they cut well, clean out the swarf as they go and it means you only need to tap once not two or three times as you do with the usual set of three taps.



For the following operations I like to use a machining plate as it gives good flat surfaces that you can run a DTI against when setting up the irregular shaped casting and also gives a good surface to clamp down.

Here I have clocked the long edge of my well used machining plate true along the mill's X-axis, located that edge and established my ctr line a known distance from it (50mm in this case) and then using the previously noted DRO positions drilled and tapped so the casting can be screwed to the plate. The bearing caps were then screwed into place ready for boring.



Knowing the exact lathe ctr height above my cross slide and the thickness of the plate it was simple to work out how much packing was needed to bring the bearing split line upto ctr height, clock the edge of the plate true across the lathe and then start machining. First I used a 16mm 4-flute cutter to produce a flat edge by machining away the draft on the base and stopping just as the cutter touched the bearing cap. I followed up with a 6mm ctr cutting 3-flute cutter to remove the pip left by the conventional non ctr cutting endmill.



This flat surface could then be spot drilled followed by a 6mm stub drill and then the far end was done with long series ctr and 6mm drills. Following that a spot facer I had made for a previous engine was used to flatten the remaining three faces.



I could then drill out 10mm followed by reaming size for 12mm. If you want to take the option of having the crankshaft run in the cast iron then just drill to 9.7mm and then ream 10mm



A machine reamer was used to finish the holes to 12mm ready to accept the bearings.





That's enough for one night, next time the crankcase can be completed and these three main castings brought together. In the meantime a quick vid of the drilling and boring on the lathe and no the reamer is not going backwards!

Yes looks a bit short to use the existing nut.

What is the diameter of the thread on the old stud, as I said a custom nut with a shoulder that will reach down into the toolpost hole may be all that is needed.

Also to check the size of toolpost to suit your machine what is the thickness from bottom of the old 4-way tool post to the surface that the lathe tools rest on?

From previous threads on here at least some Vertex items are made in China so you may just have a Chinese boring head made there to a good spec.

Although you may be canging posts and therefor stud I have afeeling the old stud would do.

Also although swing or ctr height of the lathe does come into it what is more important when sizing a toolpost is the distance between lathe ctr line and the top of the cross slide. Look at the details on ARC's site about how to size your toolpost and work out which will allow you to get the tools to the correct height.

Supplied stud with the toolpost is I believe 10mm and threaded M10. Your existing stud looks to have a 10mm body so will pass through the toolpost unlike the Myford one which won't hence the need for a different stud.

New stud looks like it might be the right length to protrude above the toolpost so at best all you would need is a large washer to replace the supplied flange nut and then tighten with your existing toolpost nut. If you short then a custom nut with extension to reach down would not be hard to make.

It is quite likely that whatever toolpost you choose some alteration to the stud may be needed

Edited By JasonB on 30/07/2023 08:01:43

Although my lathe is larger I went and had a look, after removing the four M6 cap head screws a few taps with a copper hammer had the base ring off, it was just being held by the roll pin. I suspect the pin is only there to make sure the ring goes back in the right place as it carries the angle scale for setting the topslide at an angle.

As for the stud can you post a link to the ebay listing with the videos, I suspect you were looking at ones sold for Mini-lathes which have athreaded hole for the stud, your sis a slightly larger machine.

Some but not all roll pins on teh far eastern machines have an internal thread so you can put a screw in and then pull on the screw but not sure if your one will.

Not sure it screws together anyway

STOP RIGHT THERE Margret. You don't need to be undoing those screws to get to the toolpost stud so don't worry about getting the stuck one out and put the other back.

You need to wind the moving part of the top slide off the base and then you should be able to dribe the stud down & out

My bet is they are poor quality M6 x 1 x 10mm long

Edited By JasonB on 29/07/2023 16:38:25

When I'm using the Vertex one with it's fixed 0-360 scale I'll often just put a bit of masking tape where it suits and mark a line against the Zero,

I've not found the screws on my Soba boring head mark the shanks of Brazed tip, HSS or Indexable tools so have not bothered to add any flats. Would rather have the option to tweak their position in the boring head when needed.

Looks like they just sent you a lathe boring tool, the ones for boring heads tend to be a bit different

Boring heads tend to be sized by the diameter of the head so you might have a 30mm head or 60mm head depending what you call width and height. Neither of which is a standard Vertex size.

Edited By JasonB on 29/07/2023 13:26:56

You could make a sub table with as many holes etc as you like.

Having a table where the 0-360 scale can be moved saves any problems getting the slots or an edge of a part aligned to 0 or 90 (X or y)

These engines have an atmospheric inlet so you can't do much to alter the timing on that, just the exhaust. Inlet will typically open after TDC as it needs the vacuum created in the combustion chamber to open the valve against it's light spring.

Other option would be a bigger pinion on the engine, as you will be doing away with the clutch that usually has the gear attached you are half way there already. Just size the axle gear to suit. Big advantage with a setup like this is you can easily change ratios which you can't do without a complete new gearbox if the angle grinder option has too low a ratio. Though tyre diameter can be brought into play.

Couple of examples here, bit on gearboxes here

Edited By JasonB on 28/07/2023 18:27:23

I'd go with two flat side plates bored to take suitable bearings for the solid rear axle. Tap the bottom edges to fit to the chassis. Have front and rear plates that fit between the side plates the front one of which has bearings for the prop shaft

I made similar years ago for a 1/8th scale buggy

Quite a few tether cars run transverse engines which could be done with a belt or spur gears or if you are feeling adventurous then a slave crankshaft can be used driven by the existing crankshaft to take your two rear wheels

Edited By JasonB on 28/07/2023 16:43:29