|Ian Richardson 6||29/10/2020 09:00:37|
|6 forum posts|
Hopefully somebody can assist with this issue, my AEW Viceroy milling machine has a stripped worm wheel in the bed feed gearbox (it was like this when I bought it).
The worm coming from the motor is not too bad but i think its best to replace both, the 2.1/8" od 60DP wheel has totally stripped its self and need replacing.
Does anybody know of a company who do one off gear work and could make me replacements whch wont break the bank!!
The alternative would be to buy one of the 240v electric X axis feed units thats currently on ebay for around the £150 msrk, but this would involve modifying the machine which i dont really want to do if i can avoid it.
Any help would be appreciated
|Michael Gilligan||29/10/2020 09:08:45|
16616 forum posts
I have never used them, Ian ... but I always ‘like the look of the place’ when I drive by Leek Gears
**LINK** : https://leekgears.co.uk/about-us/history/
They would be my first port-of-call ... purely on instinct.
|Clive Foster||29/10/2020 09:19:35|
|2458 forum posts|
Time for a good hunt round the suppliers catalogues. Its highly likely that AEW used a standard worm and wheel pair modified as required to it their shafts rather than making their own special design. Back in the day large numbers of angle drive worm gear sets of similar sizes were used by motor companies like Parvalux et al and by special purpose machine makers.
Even if its not still listed, the range of stock listed imperial gears has fallen over the years, modern CNC machining has made one-offs relatively less hideously expensive if companies have the design data on file.
Can't see that the exact ratio or tooth size is super important so something nearly the same that will work at those centre distances should do fine.
Alternatively consider buying, or making, a worm and having some worm wheels 3 D printed. I'm sure someoen on here could do some for a reasonable contribution to the beer fund.. Not a strong as metal but if made with maximum engagement profile they should have a reasonable lifetime in careful home shop owner hands.
|john fletcher 1||29/10/2020 09:29:01|
|630 forum posts|
HPC at Chesterfield 01246 455500 and Davall in Hatfield might be able to help as both have an extensive catalogues, with a large range of gears I haven't a phone number for Davall sorry to say, as their catalogue is very old and they might have moved, been taken over by now, .or even closed down. John
|John Haine||29/10/2020 09:33:32|
|3422 forum posts|
Not at all! **LINK**
|Colin Heseltine||29/10/2020 09:44:41|
|479 forum posts|
Turner Gear and Engineering Ltd. in Bilston.
I have not had gears from them but my colleague used them for many gears for gears for his engineering business.
I have been there with him a couple of times and its is an amazing place. e.g thousands of gear hobs in all sizes keyway broaches in their hundreds some up to 6ft long.
|843 forum posts|
I have used Kenward Precision & Gear in Huddersfield (which may not be convenient for you) for work (link above).
They do a lot of machine tool gears but, being an industrial supplier, I would not expect a 1 off part to be cheap. It will, however, be very well made.
|Chris Evans 6||29/10/2020 13:46:45|
1779 forum posts
Pritchard Gears in Wednesbury West Midlands. (junction 9 M6)
|Bob Rodgerson||29/10/2020 14:16:58|
|595 forum posts|
I have used Leek Gears before and can recommend them. It's worth going there just to have a look at their workshop and machining capabilities.
|Pete Rimmer||29/10/2020 19:56:18|
|807 forum posts|
60DP is very fine for a machine feed of that era. Could you put up some pictures of the offending part Ian.
|Ian Richardson 6||29/10/2020 20:18:29|
|6 forum posts|
Edited By Ian Richardson 6 on 29/10/2020 20:35:47
|Ian Richardson 6||29/10/2020 20:32:24|
|6 forum posts|
Thanks for all the contacts i will follow these up and hopefully get something sorted out, just posted a couple of photos to show the damaged gear wheel, this was done years ago i would think and the worm wheel also had the drive key removed and a shear pin installed instead, presumably to act as a safety feature.
I have been through several gear catalogues but cant find anything close to the old one so asume its a special gear made for the machine by AEW.
I thought of turning off the old gear and pressing on a blank replacement gear bored out to fit over the boss, saving all the work involved and keeping the cost down.
Thanks very much to everyone for responding to my inquiry
If i dont have any joy i will have to go down the 240v drive unit route and mod the machine, something i dont really want to do
Edited By Ian Richardson 6 on 29/10/2020 20:33:33
|Michael Gilligan||29/10/2020 20:34:20|
16616 forum posts
Sorry, Ian ... but I struggle to see that as 60 DP
May I suggest you take a look through these pages, and check the numbers : **LINK**
|Sam Longley 1||29/10/2020 21:29:21|
|800 forum posts|
These do custom gears
Edited By Sam Longley 1 on 29/10/2020 21:31:46
|Pete Rimmer||29/10/2020 21:54:11|
|807 forum posts|
If that gear was 60DP it would have around about 125 teeth. Looks like it has about half that.
What is the pitch of the worm Ian? And the diameter?
|280 forum posts|
It does look rather coarse for that. so I agree.
Just for reference, this page:
gives 50.8 DP as having a circular pitch of approx. 1/16" and 64 DP as having roughly 1/20" CP. This would mean a 60 DP worm would need to be finer than 16 tpi and coarser than 20tpi, so a rough sanity check with a thread gauge will help a lot.
|John Rutzen||30/10/2020 08:27:29|
|280 forum posts|
I bought a 60 tooth 1module worm and wheel from China for about £27. The wheel is brass about 13 mm thick and the worm is 18 mm die steel with plenty of meat left on it to machine to your sizes. I'm using it on my conversion of a spin indexer to a arduino dividing head device. You could machine out the wheel and loctite it to your centre.
Edited By John Rutzen on 30/10/2020 08:28:09
|Howard Lewis||30/10/2020 11:30:59|
|3757 forum posts|
The usual formula for calculating spur gears is OD = (Number of teeth +2 ) / DP. This will be more difficult with a form wormwheel, but a wheel of 2.125" diameter with 60 DP would have very fine teeth.
Could it be that the worm is single start and the wormwheel has 60 teeth?
This would provide a non reversible drive (needed for the feed on a heavy knee ) and fine adjustment.
Although, if an Imperial machine, I would have expected 50 or 100 teeth to make the graduations on the handwheel to be 0.001" or 0.002" with a 10 tpi leadscrew.
Counting the teeth on the wormwheel may shed some more light on your needs.
|Andrew Johnston||30/10/2020 12:08:56|
5718 forum posts
Counting the teeth on the worm wheel over a quarter of the circumference implies that the worm wheel has about 60 teeth. Given that the OD of the worm wheel is 2.125" OD the length of the worm look to be about half that. I think the worm is single start. It has 11 threads so the pitch of the thread is about 0.1". That implies that the DP of the worm wheel is about 30, not 60. If one of the parts has an integer DP or thread pitch then the mating part will be irrational. It's common to make the worm wheel be an integer DP value so the worm thread has an irrational pitch.
If I twiddle with the change gears my lathe will screwcut a worm with a range of DP threads including 28 and 32, but not 30.
|558 forum posts|
Another transmission/gear supplier I have used many times is Transpower drives/Apple gears Finedon rd Wellingborough Northants. They will make 1 off gears.
Always helpful and a good range off the shelf.
Edited By Oldiron on 30/10/2020 12:55:16
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