Here is a list of all the postings Gustav Thiesen has made in our forums. Click on a thread name to jump to the thread.
|Thread: Modified jacobs gear cutter upgraded|
Here i have a better looking Video:
Edited By Neil Wyatt on 03/08/2018 17:49:55
For my example of the Jacobs Machine I have used waste pieces of mild steel which i got from a metalworking company.
1. A counter-Bearing for the gear-cutter
The aim was to correct the mechanical instabilities when cutting big gears. The attached pictures will show you the four places for my uprade. The simplest and most effectiv step was the correction of the play of the worm
|Thread: A differential gearbox for my hobbing machine|
Excuse me, I'm not used to the conditions of the forum. Some text has disappered.
I must say that the first version of the machine with two shears was instable, because the work was done only with the help of my hands to keep the shears calm.
Many thanks to Chris Robinson!
In February 2016 i asked in this place for background informations about a gear train capable to produce prime number gears.
At http://www.lathes.co.uk/ i found a version, which was equipped with a differential gearbox helping to produce prime number gears. The first answers didn't help. So i decided to make a copy of the jacobs
But in my mind a wish list with two features was still opened:
1. Creation of a planetary gear in the form of a bevel gear differential.
As far as part 2 is concerned, I am not yet surely determined, since another way by making a connection with one of my dividing attachments with my Milling machine in the sense of a spiral milling device would also be an acceptable way.
The implementation of Part 1, however was difficult to understand, in particular the mathematical
For the bevel gear differential, 4 identical bevel gears were used according to the method of Ivan Law
Thus a more stable gear set-up had to be achieved.
On youtube you can see the machine hobbing a 127 teeth gear.
Edited By JasonB on 17/02/2017 15:03:14
|Thread: Gear hobber (mechanical)|
To Chris Robinson:
Thank you very much für your post. I'm very interested in the basics of your differential add-on. So I would be pleased to receive your informations. Perhaps you can give me some tips of the design of the add-on too.
I bought the CES Plans a couple of months ago and now I try to manufacture the different components of the machine. There is one problem with the feeding of the working head carrying the gear blank which I don't under-stand. The video "little hobbing machine" doesn't show this action.
My question is: How can I bring back the working head to the start position after the first feeding of the gear blank, to begin the next feeding with the condition to find the same cutting groove.
Hello, Duncan, Your spreedsheet seems to give a very good explanation. I will study it this evening. Another source with basic knowledge is this:
to Duncan Munro:
Many thanks for this long explanation. I must confess that my competence in English language sometimes comes to a border because I learned it fifty to sixty years ago. So I must have more time to understand what's about your chaps explanation. I will repeat reading what you have posted for some times until I will be back.
To John Stevenson: I'm looking for this differential addon of the CES hobber. Can you give more information about the construction and the use of this addon or otherwise do you know whether the plans of collegeengineering will give this information?
Many thanks Duncan!
My special aim is not to make a 127 teeth gear. This is only one of the possibilities. My main target is to build up a hobbing machine, which should be able to cut prime number gears to. One reason for this is, that I have made a dividing head last year. Because it should also manage prime numbers, i made a compound dividing head. But when it was finished i saw that the handling was prone to errors. So I have transformed the construction to a differential dividing head. I had to cut 12 gears for this. I made them by poor mans hobbing method. To facilitate and to get better results I want to make this machine.
To Engine Builder:
If use a 40 teeth gear as index gear the hob will cut 40 teeth in the blank with one revolution. This is because of the coupling by the idler gear. If I change the idler gear by two gears on the same stud, which will deliver a translation of 1,5 you will get 60 teeth by one revolution. But these teeth are not complete, it will start with little notches which will be greater by feeding and get deeper by repeating passes.
To Engine Builder:
I'm not able to give you a formula. The mechanical way to do this is based on two arms:
1. you have a gear blank and the cutting hob
2. you have a dividing gear connected with a worm
The two are connected by an idler gear. If the dividing gear has 40 teeth, the cutting hob will also cut 40 teeth. If you want to have a 60 teeth gear, you must replace the simple idler gear by compound approach with two gears which gives a translation of 1,5. I hope you can understand what I mean, I have learned English more than fifty years ago.
Many thanks for this information, but I'm visiting lathes.co.uk for a couple of years. This is a very good side and i know the side concerning the Jacobs machine. There is only a picture of the "differential addon", but no further information.
Some members of the forum have answered to my first question misunderstanding the term "differential addon".They thought that it was pointing to a special form of dividing or dividing head. In this case the term is better compared with the differential bearing of a car equipped with some bevel gears in order to transmit different speeds. All I want to know is, wether the kit or the plans of college engineering will give sufficient information to built and to use this differential addon in order to hob prime number gears. This differential addon is a later invention, the first plans from 1976 didn't deal with the production of prime number gears.
Many thanks for the posts. I hope that Mike Haughton will help with information. I'm more interested in the old- fashioned way with a gear train, i think that I'm to old for the electronical way of construction.
I'm looking for information about the gear hobber of college engineering.My special interest is pointed to the production of prime number gears, for example the 127 teeth gear. Now i want to know, whether the kit or the plans form college engineering will give enough information about the construction of the differential gear addition to the jacobs gear hobber.
My email request to college engineering to answer this question was not responded until know.
Is there any member of the forum to give me more information?
|Thread: Dividing Head|
I'm looking for plans of Ivan Laws differential dividing head (MEW 57). Is it possible to buy the instructions for
building this project.?
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.