Member postings for John Bromley

You don't say what type/size compressor you have, but a touch up gun with a 0.8mm nozzle would be about right.

That type of gun would give paint delivery not so different to an aerosol but in a flat pattern not conical.

Most general use body shop guns are 1.2 or larger. these will deliver to much paint unless used with great care. On an engine which has lots of nooks and crannies a smaller gun will allow for a little more build up in the corners without leaving runs all over.

Saying that, smaller parts you intend to spray you could use an air brush with a 0.5 nozzle and get a reasonable spray pattern and finish.

This is all very subjective and although I have done a small amount of paint spraying I am by no means an expert.

John

Edited By John Bromley on 22/11/2014 10:30:00

Edited By John Bromley on 22/11/2014 10:37:32

Ok, so call me stupid, but whats the problem?

I'm not even sure what the round thingy on the bit of wire is.

John

I don't think the diameter of the wheel is going to make a difference, one revolution of the hand wheel will move the slide the same amount as dictated by the feed screw. I'm not a Myford owner but if its a 8tpi screw for example the travel will be 3.175mm for each revolution.

John

Edited By John Bromley on 06/11/2014 16:58:17

Edited By John Bromley on 06/11/2014 16:58:48

If you continue to get a poor finish ditch the carbide tooling and get a few bits of HSS. Have a play with it and see how it goes. I have never been able to get carbide tooling to give a decent finish on a small lathe.

I am too still a novice with all of this machining lark. I think hobbies should challenge you. But when the results are constantly poor it can become tediouse.

John

If you want, you can always face off the finished part after turning it to diameter. Just make it a tad longer to start.

As you have so much material to remove you can play with the turning speeds. Just make sure your last couple of cuts are light and fed very slowly.

Depending on the tolerances required. If you leave it a couple of thou over size you can even polish it with some emery to a improve the finish, if it needs it at all.

John

They have turned out very nicely.

When I get my new mill, a ball turning tool is going to be my 1st project proper, right after making some bespoke splinters.

John

Are you using HSS tooling, if so, I have found by using a well honed hss knife tool, almost parallel to the job, gives a very good finish. Set it up so there is a little light creeping through at the cutting edge furthest from the point.

John

That size material sticking out that far will almost certainly be flexing. Try Facing/centre drilling the end and supporting it with a centre in the tail stock.

You should see a big improvement.

John

Edited By John Bromley on 05/11/2014 09:03:47

You can buy safety valves with preset blow offs.

Dream Steam sell them.

John

By fitting a 15psi safety valve you are restricting the working pressure to just that 15psi, if you fit a 30psi safety valve the boiler has the potential to reach that given enough heat/time.

The design of the boiler would dictate it is only intended for low pressure applications. With a single flue and no additional bracing, fitting a 15psi safety valve would be well within the boilers design limits. Best to be on the side of caution with any boiler, no matter how small.

Testing of boilers is what may have you thinking about doubling the numbers, this is done at twice the max working pressure.

John

Damn my slow typing!

Edited By John Bromley on 31/10/2014 09:50:59

I think these boilers are desisgned for use with small oscillators in mind. So any excess pressure would push the cylinder away from the port face.

But if they sell the boiler kit as a stand alone product, then they should provide a safety valve.

I would recommend drilling the top cap for a safety valve bush if you havn't already.

If you intend to use this with non oscillator type engines, silver soldering it may be more suitable. Without knowing to much about this particular boiler, other than what can be gleaned from the video above, a max working pressure of 10-15 psi would seem plenty.

I built a small boiler not so different to this one and it runs at a max 15psi, plenty for most small engines.

John

Ideal would be to hold the tube in a collet and cut it on the lathe using a tap or die holder against the tailstock. Not under power, but by hand turning.

John

I've had a great time today at my local ME society steam up.

Had my very first go driving a large gauge loco, a 5" Thompson B1.

Exciting and nerve racking all at the same time. Sadly it was our last running day of the year. So I shall have to wait a while before my next lesson.

Both Honda and Suzuki have built many 90 degree v twins. I have a Suzuki Vstrom 650 at present, had a Vstrom 1000 previously. Both great engines.

John

Try finding a local engineering/fabrication firm. They will no doubt have off cuts you can have for a small contribution to their tea fund.

I have a friendly fabrication firm near me, they deal with mild and stainless as well as non ferrous stuff.

John

Another vote for old carpet from me. Theres always people throwing out old carpets. When they get too cruddy and swarf filled, change 'em. I also like having a couple of pieces handy for laying on under the car.

I have a lovely medium pile coffee job at the moment.

John

Having a cheapo Clarke drill press myself, I feel your pain when drilling below 2mm. I have however managed to drill down to well under this with some patience. I have used a pin vice to get a start when the run out of the drill becomes just too much to deal with.

For drilling small holes with the lathe tailstock, rather than use a centre drill I just wind a nice sharp dead centre up to the faced stock, just enough to make a small punch mark.

John

The last boiler I did was about 6 inches long and 2 inches in diameter. To pickle it I used 200g of citric disolved in 500ml of hot water. This worked very well, taking 20-30 mins to bring it all back to shiny copper.

John

I don't currently have the time or means to construct a Loco, but when the time is right I would love to build my favourite engine, the M7.

A 5" engine would be nice.

Has anyone built one or know where I might get the drawings from?

John

The pulley should be held in place by a grub screw, I have a Clarke version of the same drill.

From memory it is in one of the pulley grooves. Tighten it up and all should be well.

John