Clock Wheel Fixture

[bcaclock]

Has anyone had hands on experience with the "Clock Wheel Fixture" for use on a watchmakers lathe. It is offered for sale by Merritt's & S.LaRose. I am thinking about purchasing one but would like to hear from someone who has used it first. I do all my tooth replacement by hand but this tool seems like it would save time.

Regards,
Bob Brown
Mt. Pleasant, Tx.

bcaclock@pobox.com

[bcaclock]

Has anyone had hands on experience with the "Clock Wheel Fixture" for use on a watchmakers lathe. It is offered for sale by Merritt's & S.LaRose. I am thinking about purchasing one but would like to hear from someone who has used it first. I do all my tooth replacement by hand but this tool seems like it would save time.

Regards,
Bob Brown
Mt. Pleasant, Tx.

bcaclock@pobox.com

[doug sinclair]

Bob,

I can't speak for the tool that LaRose and Merrits sells, but I have a tool of my own design that operates on the same principle, and it does a good job. One aspect to consider with the tool I think you are referring to is that the cutting is done by a circular saw blade, NOT a gear cutter. This means that you will have to do a lot of hand filing to profile the teeth correctly one you index the tooth with the circular saw.

My tool is used in conjunction with a full featured lathe with milling attachment, and using gear cutters. It does an excellent job. I don't know how you are set up for equipment, and whether the tool I designed would be of any use to you, but if you would like to save yourself a WHOLE bunch of money and you think my idea might work for you, let me know. By the way, this is not a commercial for my tool. The idea and the photographs I will be pleased to make available are free for the asking.

Regards,
Doug S.

p. s. For anyone reading this who is an NAWCC member, you may see my indexing tool in NAWCC BULLETIN, whole # 298, Oct. 1995, vol 37/5, pages 595 to 598.

[bcaclock]

Thanks a lot Doug. I remember reading your article, I will check it out again.
Bob

[tymekeypur]

Sounds great Doug!...but first I better set about looking for a milling attachment for my Derby' 8mm lathe...then I'll get back to you..while I've replaced individual and 'gangs' of teeth on a wheel by hand, I've never 'cut' a complete wheel from a blank...have often wished I could on the eve of setting out to find a 'replacement'...in the interim, am going to see if I can find a copy
of that Bulletin on the net...

jc #0157194

[doug sinclair]

Phil,

Glad to hear my article was of some assistance. I noticed in the December '02 issue of the BULLETIN, that the tool that tied for second place in the National Convention crafts contest is the same tool with a few differences in how it was mounted in the lathe. Looks like maybe I shoulda patented the idea!

Doug S.

[doug sinclair]

Bill,

If you are an NAWCC member, it is available in the back issues of the NAWCC Bulletin. The article is not available "on line". However, what I will do is take some digital pictures of the tool and its application, and send them to you. The article consists of 22 photographs, most of which you won't likely need. If what I post doesn't meet your requirements, I could photocopy the article and send it in the mail.

Doug S.

[feadog]

Doug,

The pictures will be a big help.

I am an NAWCC member. I'd have to order the back issue, i.e., the back issues are not on-line to members, correct?

Bill

Bill
feadog a.k.a. bildio
NAWCC Member: 0155549

[doug sinclair]

Bill,

A request to the librarian will get you a photocopy of the article if you wish. The article is called "Repairing a Mainspring Barrel (How I do it)", and is in Volume 37/5, number 298, October 1995, pages 595 to 598. I'll still post a picture here, later today.

Doug S.

[doug sinclair]

Bill,

Here is a close up of a barrel I patched using this tool when I wrote the item for the BULLETIN in '95. It shows a close up of the barrel in place on the tool, close up, in the lathe, a gear cutter on the milling head, indexing the balle to get proper placement of the tool prior to cutting. I am told my files are large, but I don't know how to downsize them.

fixture closeup (http://members.shaw.ca/doug.sinclair/tools%20001.jpg)

I'll send the picture of the tool on another email.

Doug

[doug sinclair]

Bill,

Here is the tool holding the barrel. Behind the screw in the center of the barrel is a .950 cm dia. brass hub that sits on a shelf inside the aluminum fixture. The hub is drilled and tapped with an 8 x 32 hole all the way through the center. It fits into a .950cm hole in the fixture. This hub is held in place from behind the fixture by an 8 x 32 screw that screws into the hub and holds the hub down, tight on the internal shelf of the fixture. The top shoulder of the hub fits flush with the surface of the fixture, and there is a smaller diameter extension of the hub that stands proud above the fixture to fit the hole in the barrel. A brass collar that you see held in place inside the barrel by another screw is concave on the under side. The collar and screw is loose fit to hold the barrel and allow it to turn. These instructions assume that you have fitted the barrel with a suitable plug to permit cutting the new teeth.

1./ Mount the fixture in a vise on your compound tool rest.

2./Loosen the Allen screw seen on the index below the barrel. Turn the barrel so you can orient the cutter (as in previous picture) tightly between two good teeth. Tighten the tooth index.

3./Use the quill on your milling attachment to adjust the height of the cutter, and your tail stock to adjust the depth of the cut between two good teeth as shown.

4./Once you have that cut all set, tighten the jib screws on your compound tool rest, but be certain that you can still cross feed the tool post, vise, and fixture.

5./ Back the tool post (and vise, and barrel fixture) back and away from the cutter.

6./ Loosen the machine screw on the index and the screw in the center of the barrel a bit. Back the index away, turn the barrel to present the plug to the cutter, press the index tightly between two good teeth, and tighten the machine screw. Tighten the screw that holds the barrel.

7./ Turn on the milling machine and use the cross feed to present the plug you are cutting to the cutter.

8./ Repeat to cut all of your teeth.

If you have any questions let me know.

Doug

P S this is a large file. I don't know how to make it smaller.

ready to cut (http://members.shaw.ca/doug.sinclair/tools%20002.jpg)

[This message was edited by Doug Sinclair on October 08, 2003 at 19:17.]

[doug sinclair]

Bill,

I just noticed that the business end of the fixture that indexes the barrel teeth doesn't show. I'll look after that this evening.

Doug S.

Here is the third view of the barrel fixture.3rd view (http://members.shaw.ca/doug.sinclair/tools%20003.jpg)

[This message was edited by Doug Sinclair on October 08, 2003 at 23:29.]

[feadog]

Doug,

The pictures and steps were clear, and very helpful.

I have a watchmaker's lathe and a Sherline lathe, but no milling capability.

Are the instructions for making your tool in the bulletin? I assume a milling machine is needed to make the tool, correct?

Thank you very much for taking the time to provide so much detailed information.

Bill

Bill
feadog a.k.a. bildio
NAWCC Member: 0155549

[doug sinclair]

Bill,

The BULLETIN article shows the tool in much better detail. It shows all the parts, and it shows it dimantled. There are no measurements included in the article. The article in the BULLETIN shows the whole process, including cutting out the area around the broken teeth in the barrel as well. For that you would also need a milling machine, but there would be other ways to do it. The milling machine makes a better job, simpler to do. The tool in the pictures I sent was made by a machinist friend of mine, and it is based on the prototype which I made myself. The prototype has had more use in actual repair of project barrels than the one in the pictures included here. The one in these pictures has only been used to illustrate its use. I would say that you pretty well would have to have a milling machine to be able to make one, but it is a very simple tool. Use of the tool would be somewhat limited without a milling attachment being available. But it sure simplifies things if you don't have a wheel cutting engine. It could be used to repair wheels as well as barrels, with modifications. In fact, the tools now being advertised for sale would only be useful for cutting wheels, but not barrels, as I see it. Barrels are tougher to fix.

Doug

[doug sinclair]

All,

For anyone interested in a laser photocopy of the process of repairing a mainspring barrel using the fixture in this thread, I'd be glad to do it for the cost of the copies and postage. The article has 22 photos with text, and I don't think the MB is the place for all that. The article shows the fixture dismantled. There are no measurements included in the article, but it is a very simple tool, would be simple to make with the right equipment, and dimensions aren't critical. However, If I was pressed, I could likely provide those too. Anyone who sends me a mailing address privately would get a copy of the article. My email address is:

doug.sinclair@shaw.ca

I tried to make this link live, but it didn't work.

Doug S.