Friday, April 02, 2010

Chinese crap

Several months ago I had a plan to build a project using Manhattan style construction so I decided to get a tool to make myself some Manhattan pads. Constructors in the US can buy a nice hand punch from Harbor Freight for $25 - that's less than £18. Over here the nearest equivalent cost around £90 from a tool supplier, except on eBay. I bought the eBay one, but even that cost over £30 including postage.

In the end, apart from punching a couple of test pads using the 7mm punch that was already fitted when I opened the box, I didn't use it. Until this afternoon, when I wanted to make some smaller pads. That was when I discovered what a shoddy piece of manufacturing this eBay hole punch is.

The 7mm die was a bit stiff to remove but came out with the aid of a screwdriver in the slots provided. The 4.5mm one I put in would bind at each turn and got more and more stiff. Eventually it wouldn't budge, so I put the screwdriver blade in sideways to get a bit of leverage. There was a crack and a whole piece of the die broke off! I guess it was made by the same firm that makes K3 knobs for Elecraft!

It's far enough in that I can make 4.5mm pads, but not only does it not want to go in any further but it also doesn't want to come out. I might be able to get it out with some Mole grips but this is probably the most useful size and I might never be able to get it back in again next time I need it. Crap!

7 comments:

Anonymous said...

Hey OM,

This solution may not work for you if you like your manhatten pads to be all uniform, perfectly shaped, etc.

I found a bit of copper clad board that was about 1/16 inch(about 1.5 or 2 mm) thick is easy to cut with a good pair of scissors. It probably doesn't do the scissors much good, but you can get a fistful of manhatten pads from a 4x6(inches) piece of copper clad board.

I have also used ordinary scissors to cut thicker boards, but it is more difficult, and the board is more likely to break/crack.

FWIW - The components don't seem to mind that the pads are somewhat irregularly shaped. ;)

73 de w4kaz

Dr. S. Bakfra said...

Hello
Please excuse me for my ignorance, but what on earth are "Manhattan style construction" and "Manhattan pads"?

Best regards

S. Bakfra

g4ilo said...

It's where you build something on to a piece of copper clad board which is used as a ground plane. You make little squares or pads from the same material and glue them to the board for the other connections. This article tells you more than you probably want to know about the subject.

Dr. S. Bakfra said...

Thank you so much for the information. I must admit that I find the concept a little odd...or at least very different from the more traditional ways of circuit contruction.


Best regards

S. Bakfra

Anonymous said...

Julian; you may wish to try this material to rescue your tool. If I understand the problem correctly the screw in die is stuck. My friend in Boston has recued many many electric motors with ceased bearings using this material. See web page at: http://www.midwayusa.com/viewProduct/?productNumber=840573

Chuck W5PG

Anonymous said...

Hello All

Another tool to use when cutting the pads is a pair of small tin snips which can be bought from machine mart or B&Q. With regards to the sticking hole punch die a good soaking with Plusgas available from Halfords or other car factors should help. It will take a bit of time and careful use of a mole wrench to ease it back and fro in rotation but it should eventually come free. Best of luck

Kevin G6UCY

Richard said...

Hi Julian - I've tried the DIY route for Manhattan pads and now use a small diamond bit to define the pads straight onto the substrate. If you don't want to do this, follow this link for a very cheap and highly effective solution to placing components and ICs ... once on this page, scroll down to "mePADS" & "meSQUARES": http://www.qrpme.com/

73 de Richard F5VJD