Jump to content

sgl_imaging_challenge_2021_annual.thumb.jpg.3fc34f695a81b16210333189a3162ac7.jpg

The aid of an engineering brain required please


Recommended Posts

On 24/05/2018 at 14:10, Rusted said:

Peter,

You've made hundreds? Why have I never seen them advertised? Have you stopped now?

I was told by BH, amongst many other lame excuses, that his wormwheel maker was in his 90s and didn't want to do it any more.

I know how they're supposed to be made. I thought I'd paid to have it done properly to the highest standard.

Had I known what would eventually turn up I would have made my own the correct way.

I think the 11" I had from BH was lying on a shelf as a reject for half a century.

Perhaps I was seen as an easy touch being on the Continent and impatient to progress on my big GEM?

I "retired" 12 years ago. The gears were mostly for complete telescope orders although I made some specials for MOD and aerospace projects. I hardly ever advertised anything, reputation brought in as much work as I could manage.   ?

  • Like 2
Link to post
Share on other sites
  • Replies 59
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Popular Posts

Results time: After many days of generating swarf on an industrial scale, I finally have all the new parts made: I'm not responsible for the round bits you understand! I decided t

Without being able to see the mount first hand I would hazard a guess it would be down to moment of inertia. The moment of inertia on the DEC axis is many magnitudes larger than that of the RA ax

Thanks for that comment Dave, as you say counter intuitive, but very true. Spent yesterday fettling and playing, and yes, reduced spring force made a great difference. Previously I'd let Sit

Posted Images

Just an observation, but my dentist has a rotating slideshow in the waiting room. As well as wildlife pics, expensive holiday shots and adverts for tooth whitening one of them is a chart of how abrasive different toothpastes are. Some are rated as so abrasive they are bad for your teeth. Arm and Hammer which is mostly bicarb or soda is rated as the least abrasive and may be too gentle to do anything significant to aluminium. I found a copy of the chart:

image.thumb.png.ddf772056d4a1cc1b1fd5eb89c1e624e.png

It seems A & H is only twice as abrasive as brushing with water. You want Colgate 2 in 1 Tartar Control/Whitening!

It seems different toothpastes really are different.

  • Like 2
  • Thanks 1
Link to post
Share on other sites

Now that is interesting, I used Arm and Hammer Advanced White, bit it sure was not after three hours on the gear set, mucky grey would have been a better name for it.

  • Haha 1
Link to post
Share on other sites
36 minutes ago, Horwig said:

Now that is interesting, I used Arm and Hammer Advanced White, bit it sure was not after three hours on the gear set, mucky grey would have been a better name for it.

You'll have to swop to A&H Fresh Mint it will smell nice as well. lol

Dave

  • Haha 1
Link to post
Share on other sites

Interesting (sort of)...  Coincidence...

Quote

Arm & Hammer

In the 1980s Hammer owned a considerable amount of stock in Church & Dwight, the company that manufactures Arm & Hammer products; he also served on its board of directors. However, the Arm & Hammer company's brand name did not originate with Armand Hammer. It was in use some 31 years before Hammer was born.[47] He was spurred to buy shares in the company as a result of often being asked about the brand being so close to his name.

 

Link to post
Share on other sites

At least when you finish with all this toothpaste you can be sure that your gears will have lovely clean teeth :D

I have always been a little wary of the abrasive effects of toothpaste since I heard it recommended for polishing clear plastic parts used in plastic model kits.  My dentist claims that some of my teeth show signs of heavy wear.  Aside from making me feel like a horse, perhaps I shall give consideration to Neil's chart when I next buy toothpaste.

But to return to the actual topic, I just wanted to say that the worms in the photos posted by Huw in the early hours of yesterday morning look like things of beauty.  Good engineering is often as much art as science.

James

  • Like 1
Link to post
Share on other sites
On 14/05/2018 at 14:00, Davey-T said:

I discovered that the worm tensioning spring can be too strong and counter intuitively it worked better with a "weaker" spring but the number of turns and strength made a lot of difference so a weaker spring with more coils worked better.

Dave

Thanks for that comment Dave, as you say counter intuitive, but very true.

Spent yesterday fettling and playing, and yes, reduced spring force made a great difference.

Previously I'd let Sitech handle the backlash, but I've now let PHD handle it, here's last night's first run (edit, actually it's from the previous night):

phd1.thumb.JPG.01e2fbfedfb0bbb0c21a71180c0e471f.JPG

As you can see horrible periodoc error, so ran Sitech's Auto PEC routine for 9 worm revolutions:

phd2.thumb.JPG.49c9919b145b759fec564ec773d5cca9.JPG

I was amazed at how the RA error just kept getting smaller on every revolution, really easy to apply.

Let's hope that everything is now stable and repeatable.

Huw

 

Edited by Horwig
  • Like 3
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.