Member postings for Steamer1915

I have just had a play with Gearotic and was looking at an example of a Herringbone gear. I understand that for the gears to be in line with each other (as opposed to being at ninety degrees) there will be need to be one right-hand and one-left hand gear.

The query I have is that it would appear that there is no rounding of the apex of the tooth to correspond with the radius left by the cutter at the "internal angle" for want of a better description.

The simulation doesn't appear to show any rounding of the tooth apex. Is this something that is taken care of when processing the G code?

Best regards,

Steve.

Ray,

Could you give us a brief rundown of the specs of your new computer please? I will have to take the plunge as my current laptop won't run Fusion properly. Graphics card issue that can't be updated.

Steve.

Nice work there Jeff. Are you still requiring use of the surface grinder?

Best regards,

Steve.

I had experience of this many years ago on my S7 and I can do no better than repeat Phil P's post verbatim.

Best regards,

Steve.

Welcome Jeff, See you at Tony's "do" hopefully.

Steve.

Hello Martin,

No worries. All I was trying to point out is that there is a difference between the angular positioning of the countershaft (as you have correctly alluded to) between the Non PCF (your original machine) and the PCF (your present machine) models. That is why I don't mark the back-plate and leave that to the customer. I would imagine that even if your apron has been re-manufactured, the angular positioning of the countershaft would remain the same.

My best regards,

Steve.

Martin, Glad that all has gone well.

My personal preference is to have the line at the 12 o’clock position.

It was intended to mark this during production of the dial but unfortunately, there is a slight difference in the angular positioning of the back-plate between the power cross feed version and the non power cross feed version. Therefore, a pre-marked line may be in an inconvenient position for the lathe user. Position of lighting can be a big factor.

Best regards,

Steve.

Yes Martin, you bought it from me at Harrogate in May 2014. You were number 57 according to my records. I have now sold over 130 with a recent flurry on eBay.

I have modified the fitting instruction sheets with some supplementary notes about fitting to the PCF versions and later lathes with the different screw placement.

I hope the dial continues to give you good service.

My best regards,

Steve.

Edited By Steamer1915 on 07/12/2016 15:24:28

Hello Martin,

Below is a copy of the drawing of the jig that I recommend when drilling the original shaft. This drawing is included as part of the fitting instructions that I supply with the dial. You pretty much have the same idea. I will also include a paragraph from the same instructions:-

"Whilst the majority of Power cross feed machines will be able to utilise the apron oil level screw to anchor the back-plate to the front of the apron, some of the later machines have the oil level screw positioned to the left of the earlier placement. In such cases, the dial should be fitted as per the non-PCF versions. It should be noted that there may be an issue with the wall thickness of the front of the apron casting and therefore it may be necessary to drill the tapping size for the M4 thread to a depth of only 8mm. This will prevent breaking through into the cavity and subsequent contamination of the oil. In this instance, it will be necessary to slightly shorten the 16mm long M4 cap-screw so that it grips the back-plate before becoming thread-bound at the bottom of the hole."

Hope this helps,

Best regards,

Steve.

If I am cutting a full form Whitworth thread, I usually use a inserted tip of that form. The nominal dia is the same as the major. Never had any trouble mating parts.

Steve.

Sorry Norman!

Steve.

From S7 manual:-

Also, George Thomas explains how to solve this problem simply on page 281 of his  book "The Model Engineers Workshop Manual".

Best regards,

Steve.

Edited By Steamer1915 on 04/10/2016 18:54:06

When I first started making the Graham Meek designed Graduated handwheel for the Myford lathe, I needed a reliable, repeatable method to produce a fine knurl on the periphery of the dial body.

I ended up utilising the slotting head that had lain redundant at the rear of my Bridgeport mill since I acquired it. The general idea is that the slotting head behaves in the normal manner but a rod connects the movement of the ram and indexes a rotary table via a ratchet borrowed from an old steam engine lubricator.

The original ratchet wheel was replaced with a wheel that had only seven teeth and this allowed an amount of overstroke, which in turn allows the cutting tool to clear the work before the indexing for the next cut takes place. The tool is ground to give a 90 degree tooth form and the job takes 8 minutes to complete one revolution. In this time I can prepare the blanks for this op and the finishing op when the “knurling” is complete. There are 504 “teeth” which gives a pitch of just over 0.016”. I hope the photos show the idea of the setup adequately.

Best regards,

Steve.

Why this text appears in the middle of the photos, I don't know!

Just worked for me.

Steve.

There are styli available for some lever "clocks" that are tear drop shaped to compensate for Cosine error. I believe that this may be an involute shape.

Best regards,

Steve.

Edited By Steamer1915 on 21/09/2016 11:22:52

Edited By Steamer1915 on 21/09/2016 11:24:45

I can only agree with you Neil, I was given the "Tich" book as a birthday present in the early '70's after seeing it advertised on the back of the Model engineer magazine. I started the loco at school during Metalwork classes and made a few parts. I didn't make a lot of progress and then life started to get in the way. I fully understand that it may not be the ideal beginners engine to build but I still think that the book gives an excellent introduction into Model Engineering for any beginner. "Read the Tich book and then build a Simplex or Rob Roy" is a common cry. To dismiss it as a "Useless ornament that lives on a shelf" is very unfair and as many examples have proven, totally untrue. I find it very annoying when people feel the need to spout off about what some builders regard as their pride and joy, just because they don't like the model in question. In this particular case the wrong engine was targeted and the thread was derailed. Rant over.

Steve.

Well said Michael!

Steve.

Even in 5"? ...or did you miss that bit?

Steve.

Robert,

Thank you for your kind words, I hope it will give you many years of good service.

Neil,

The 18 cylinder radial is built to Lee Hodgson's drawings (Ageless engines, USA) I think it would probably be more accurate to say that it is very loosely based on the Pratt & Whitney double wasp. The biggest issue I have had up to now was making the cylinder heads to a shape that I was happy with. I wanted to keep a constant fin width on the top fin and this could only be achieved by making the top of the head a spherical radius. Given that the head & valve towers are machined out of one piece of material, machining around the valve towers, whilst retaining the spherical radius proved to be a challenge.

Eventually, the penny dropped and I was able to achieve the desired effect. Progress has been stalled by dial production but I hope to restart the project soon. There is a photo in my albums for anyone who is interested.

Best regards,

Steve.

Just looks like the brown colour that is left after heat treatment. Perhaps done in a vacuum.