Starrett 18a automatic center punch "misfire"

[NCCheesehead]

So i picked up the Starrett 18a a few months back. I'm not sure what is going on, user error or defective. Problem comes in as sometimes the automatic feature works great for 1-2 punches then it misfires or fails to punch. I can unscrew it fiddle with the spring and reassemble and fires 1-2 times then nothing. Any insight?

 

[Shiftless]

I have the same tool with the same problem, I’m in for an answer from a GJ expert.

 

[Hohn]

Sorry I can't help, I have the 18C. It's never had an issues other than it requires a lot of force to fire, which I think is a feature and not a bug.

 

[64C10]

Next time you have it apart to adjust, clean everything off with brake cleaner, then put back together with some 3-in-1 oil on all the parts. For what they are, these things are extremely sensitive to cleanliness.

 

[NCCheesehead]

I did exactly this before I made the post, unfortunately no change

 

[64C10]

Odds are there’s a burr in the barrel or another pseudo-obstruction. I’ve never had an automatic that didn’t require some degree of fiddling to get it right.

 

[RTM]

Next time you have it apart to adjust, clean everything off with brake cleaner, then put back together with some 3-in-1 oil on all the parts. For what they are, these things are extremely sensitive to cleanliness.

This worked for mine too, there was a bit of crud causing the thing to get a hair off center. A quick look at the parent will explain the mechanism a bit.

 

[ecotec]

Odds are there’s a burr in the barrel or another pseudo-obstruction. I’ve never had an automatic that didn’t require some degree of fiddling to get it right.

I agree with this diagnosis. The spring is binding up on something. A burr or obstruction is probably the issue.

 

[tripplejl]

I took mine apart with the same problem. Although I couldn't really see a burr I took a light stone cleaned up the mechanism. It has worked fine since.

 

[i84x]

I've had this issue with all auto punches including a Starrett 18-AA. I usually just tap the top on the workbench and it'll be OK again for a few more punches.

 

[dutchgray]

I have several Starrett automatic centre punches which work just fine and one that I can't get to work properly no matter what I do, which is an 18C

 

[danielbuck]

try contacting starrett? I've got two that I've used for the past 15 years or so. occasionally I'll have one depress and not pop, but pretty rare.

 

[woody 73]

Again, just curios but by any chance were the center punches coming from mainland China.

 

[whateg01]

I would choose the pool you use carefully. Don't want to gum it up.

The 4 or 5 cheap ones from if I own only required loctite to keep the cap from constantly unscrewing. Honda, I mean, starrett quality isn't what it used to be.

 

[woody 73]

Yes, when they started coming from China the quality began to slip up.

 

[Rinspeed]

A little oil will usually fix them.

 

[Beerhippie]

My 30-odd-year-old 18-A works fine. Top does like to unscrew.

 

[whateg01]

... Top does like to unscrew.

Good to know that when the Chinese copy something, they go all out!

We had a model that was being replaced with an updated version. First chance we got, we started putting it through its paces. Found several bugs in the software that has existed on the old box. Asked engineering about it and they said they were told to replicate the functionality of the old box. So they did, bugs and all!

 

[Rinspeed]

Yes, when they started coming from China the quality began to slip up.

Still made in USA.

 

[Steve_P]

Sorry I can't help, I have the 18C. It's never had an issues other than it requires a lot of force to fire, which I think is a feature and not a bug.

That's normal. You might consider an 18A in addition; it's much easier to operate and works fine on mild steel.

 

[Rinspeed]

That's normal. You might consider an 18A in addition; it's much easier to operate and works fine on mild steel.

That doesn't make any sense seeing the spring tension is adjustable by backing out the top cap.

 

[64C10]

That doesn't make any sense seeing the spring tension is adjustable by backing out the top cap.

18A has a considerably higher spring rate and is made for harder materials. Even dialed all the way out, they’re pretty tight.

 

[Beerhippie]

18A has a considerably higher spring rate and is made for harder materials. Even dialed all the way out, they’re pretty tight.

Maybe mine needs a new spring. I use it to make a mark to locate a REAL hammer-driven center punch.

 

[darkzero]

I haven't had to fix my Starrett 18A but I have had to fix a few of my General center punches & of course a HF one.

Rather than take pics & try to explain what I do, here's a few videos that pretty much cover what I do. I'm sure there are better videos but these came up in a quick search.

For the ones that are really bad I use the lathe to face the end of the pin & the face of the hammer. Some center punches will have a bent/curved spring. Some will simpy just cut the end off the spring rather than having a spring seat to make the spring sit canted

I bought two (at different times) General #89 stainless steel body auto center punches from Amazon Warehouse. Neither one of them fired at all which is probaly why they got returned. I fixed both of them & they have been consistently reliable. These had a ball bearing in them, none of the prev center punches I have owned had a ball inside them. Took one to work, the other is just another spare at home.

 

[Hohn]

That's normal. You might consider an 18A in addition; it's much easier to operate and works fine on mild steel.

I can adjust the 18c down a bit if needed. I prefer the harder hit.

 

[64C10]

Maybe mine needs a new spring. I use it to make a mark to locate a REAL hammer-driven center punch.

That’s pretty much all they are for, but when I’m laying out a flange or baseplate with multiple holes, I want that mark to be clear/deep enough that I don’t have to waste 10 minutes looking for my starter mark before I can punch it.