By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Forum House Ad Zone

How to make a hollow punch for making teflon washers

All Topics | Latest Posts

Search for:  in Thread Title in  
OldMetaller21/11/2015 09:15:56
203 forum posts
25 photos

Gentlemen, I need to call upon your knowledge once more. A colleague is restoring a Class 50 diesel locomotive and he needs 180 teflon/ptfe/delrin or suchlike washers, 1mm thick by 34mm od and 18mm id. The ones he has priced are too expensive as he is on a budget, so I've said I'll make a punch for him to make his own washers from sheet material.

My question is, will mild steel suffice for this punch if he uses a soft cutting mat or something for the anvil, and is there anything I can do to the edges of the punch after I've turned it to shape to make it stay sharp for 180 punching operations?

Thank you,


David Clark 121/11/2015 09:25:53
3357 forum posts
112 photos
10 articles

I would make a simple press tool. Two sheets of say 3mm steel with a 1mm + spacer. Bore the 18mm hole through both strips and make an 18mm diameter top hat punch from silver steel and harden it. Use a bench vice or similar to press the hole. Then put the embryo washers on an 18mm mandrel and turn the od.

Clive Hartland21/11/2015 10:46:44
2838 forum posts
40 photos

I made a punch to make breathing holes in Bee Hive lids and turned a piece of EN8 and made 30 deg edge and then made a hollow rear set to match and threaded a hole through that and use a 10mm bolt to pull it through the 3mm ply. It cuts fine with no splintering at all. and it's been in use for about 10 years. I did not harden it.

For your needs I think you will need 2 punches, one for 18 mm and then a bigger punch with an 18 mandrel to guide the larger punch, again using the large vice as a pressing tool. A backing block to allow the 18 mandrel to go through as well. With 180 to make it's worthwhile making a decent punch tool.


Circlip21/11/2015 13:42:30
1531 forum posts

Think I'd be inclined to make a compound punch and die, OD and ID at one stroke. Punch - tube, 34 OD 18 bore, Die- 34OD plate with an 18dia centre slug mounted on a backing plate with pin ejectors.

If doing it the long way ie. separate P & D, punch the ID first.

Regards Ian

OldMetaller22/11/2015 05:54:34
203 forum posts
25 photos

Thank you all for the ideas and suggestions. I'm going to attempt something to day, if it's not disastrous I'll post a picture!

Regards, John.

Chris Evans 622/11/2015 10:18:28
2068 forum posts

Take a look at the Clark wad punch and copy the idea of a spring loaded centre. I am soon to make one for felt oil seals of similar dimensions.

David Clark 122/11/2015 13:19:08
3357 forum posts
112 photos
10 articles

You could possibly use a hole saw or two. Easy to cut the outside first then the bore and clean up on the lathe.

KWIL22/11/2015 16:40:36
3564 forum posts
70 photos


You have a PM.

Danny M2Z22/11/2015 17:00:03
963 forum posts
2 photos

I recently made a punch using the info that I found here **LINK**.

Use the search function to find the article ' How To Make a Simple Gasket Punch ' , tick the box labelled 'Match all terms specified'

Another simple punch that I made a few years ago to cut discs worked much better by mounting it in a drill press and spinning it whilst gently pressing down (as opposed to just pressing it).

As for wear on the cutting edge, holding a sharpening stone against the side of the punch as it rotates works fine.

* Danny M *

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Sign up to our Newsletter

Sign up to our newsletter and get a free digital issue.

You can unsubscribe at anytime. View our privacy policy at

Latest Forum Posts
Support Our Partners
Eccentric Engineering
Rapid RC
Eccentric July 5 2018
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

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.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest