Member postings for JasonB

From measurements of my own one it is the male taper that is a bit long beyond the gauge dia.

Gauge dia for B16 is 15.773mm

As best I can measure on mine against the back of the chuck it is 15.71mm

So that is a difference of 0.023mm

After a bit of trig if the gauge were spot on that would only allow the taper to go a further 0.4mm in. Which is far less than can be seen.

On no standards can I see a requirement for the length of taper beyond the gauge dia.

About what you could expect from a £150 Rohm chuck, these are all 0.05 runout.

Albright High Precision would  be 0.04mm runout and cost £275

So I would say save your money on the wedges

Edited By JasonB on 16/01/2022 08:00:27

Recent thread on wasting your money buying shims

I don't use a DRO on the lathe

I'll usually run a Dremel with orange teardrop shaped stone in it lightly over the surface to remove and high spots which is usually enough to get a paint finish that still looks like it was a casting as there will be some slight surface irregularities. You can do more if you want a mirror smooth painted look. Scale also comes into it as a casting from a half scale traction engine will tend to need less prep than a 1/12th scale model to get the same size original cast finish to look right as the same sand is used for both castings

I did a Stuart 7" flywheel last weekend this shows it before. A good casting with little flash and well lined up halves, flash was filed off before machining, dremel after as I wanted to also blend in the turned surfaces that will be painted with the cast ones.

And after

That will most likely get a coat of high build primer, rub down and then final prime and colour.

This thread goes into a bit more detail of how I finish castings and a few of their "features"

Edited By JasonB on 15/01/2022 07:19:47

this thread might be of interest

If it was not for the slow setting requirement then Loctite 380 "blackmax" would do nicely

Thanks, dealt with.

I don't think I would want to go back to using a single or 4-way post.

Can't see the comment that they are as quick to change tools as one 1/4 turn does my QCTP, a 4-way would be between 2 or 4 screws and if the shank of the tool is not the same then each will require several turns of the clamping screw.

Also it is not just the repeatable height of a QCTP that is it's sole advantage you can swap tools and they go back in the same place usually to with in a thou so if you are making a couple of parts that need two or more tools you can set your handwheels for the first, change tools and then when you go to make the next just use the handwheel readings rather than having to measure again as the tool is unlikely to go back into a holder in the same position twice without a QCTP. Indexing 4-ways accepted.

Though time may not be an issue for the retired who have all day to potter about in the shed those that work and have family commitments may not get as much workshop time as they would like so would rather be cutting metal than adjusting tools.

I have a holder for all each of my commonly used tools and two that get used for "odd" ones and find that works well for me.

My QCTP is also smaller than the supplied 4-way so I can get in closer when using tailstock support without excess tool stick out and if needed I have extended holders so can get it really close which would not be possible with the 4-way.

Thanks, I've dealt with them but they may show down the right hand side for a while but won't open

For a start it is Stuart not Stewart!

The S50 was the replacement for the slide valve horizontal progress and they distinguished between the slide valve and oscillating progress engines by using "S" for slide and "O" for oscillating so that is most likely where the "S" came from.

I think the 800 gas engine is the highest number off the top of my head so not sure where the 50 came from and they also have quite a few that are just names, or letters such as the Lightweight or BB.

Good history of the various engines to be found here

How to post photos

Yes sorry you are right on the chester, it's the same size DB11 as the 280 that does not have the separate shaft.

The brushless motor on the 290 is a new thing so I don't think you will find many that have used them, it would be interesting to know if it has just one belt position or hi/lo like the Warco. I also think the Amadeal has D-13or4 spindle so easy chuck changing

Also surprised that you can't fit a 40mm disc into the chuck or do you not have outside/reversible jaws for it?

Also hard to see why you were advised to rough turn from the outside in as that would have meant you start cutting the jaws at about 80mm dia, doing from inside out as is normal the largest dia would be the 40mm??

If the step was only for a 40mm dia disc then don't worry about the speed 400rpm will be no problem.

Thin penny washer was not teh best thing to use, something a bit thicker would be best.

There is no real need to wast that much jaw depth for one job, 1 to 1.5mm depth would have been more than adequate as a "disc" assumes your steel is reasonably thin so little overhang. Just take light cuts off the steel

As for pictures you have already got one in an album so add some more and then when you get to where you want the picture in teh post click the little camera icon along the top of the box you are typing in, select album and then image and click insert

Edited By JasonB on 12/01/2022 13:40:12

I generally try and keep the speed as reccomended and often towards the high side as it helps with the vari speed machines and just adjust feed rate and DOC to suit the job.

I can't imagine the Taig is much different to my Unimat 3 and I happily did a Stuart 10V on that running the two feet of the "a" frame at over double the speeds talked about here for cast iron with HSS and that's an intermittent cut about 3" out from the chuck/faceplate.

As I said earlier the different aluminium alloys have such a broad range of cutting speeds from 400-1200 ft per min even allowing for a light machine and the intermittent cut 400rpm should be fine with a light feed and DOC if using HSS as it's at the bottom of the range. Good old Tubal Cain in his ME handbook for example would have us roughing 4" aluminium at 570rpm and finishing at 760rpm

My old Narok drill also gets used to broach keyways

As Mike says it is seldom used to drill holes at least for engineering work but is good for use with a cylinder hone, drum and disc sanders and things like that.

The SX1P he links to does not have as much head room as the average bench drill, very little quill travel or the drilling capacity (dia) so depends on the size of the work you need to do

Edited By JasonB on 12/01/2022 11:16:45

Could use a **GT insert to turn the steel then no need to bother about reducing the speed

That is assuming the disc being already round needs it's OD turning or facing and not just a hole bored in it.

The Warco is three phase with inverter not brushless so should be a better bet. their 290 is also 3 phase with inverter.

The Chester does not have a separate feed shaft unlike the other two and is a smaller lathe so would expect it to cost the least. It is the same capacity as a warco 250.

I don't think Amadeal tend to supply a 4-jaw, faceplate or steadies with their machines so add in teh cost of those as Warco and Chester do

Without knowing what the engines are and what you intend to do with them it is almost impossible to say what would suit.

The smaller the capacity of an engine then the less volume of air needed so a small airbrush size compressor with no tank may be fine for something upto 20mm bore x 20mm stroke but if you have a large 50mm x 50mm engine then it's capacity will be more than the compressors displacement.

Linked to this is the speed you want to run at, the slower the engine the less volume of air it will need per minute so that 50x 50 may tick over on a mid size compressor if you just want it to run at 60rpm but the compressor will not keep up if you want to run at 600rpm

lastly comes what you want to do with the engine, I generally just like to run mine for display and turn the compressor down until the needle is hardly off the stop so 5psi (o.3bar) at the most. If on the other hand you want it to drive say a generator or pump then depending on teh load they put on the engine you will need to increase pressure so that cheap comp that has a FAD (free air delivery) of 2cfm at 20psi may only have half that at 50psi

One other thing to consider with no storage tank is that teh compressor will be running all the time and the cheap ones are often very noisy so that thought of relaxing and watching your latest creation ticking over will be shattered by the deafening noise of the compressor.

Anyway who needs a compressor