Dowel Pins With Nice Finished End

[John2002]

Hello,

Does anyone know where I might find hardened dowel pins that have at least one end that is crowned or beveled in a nice consistent manner?

I have an application where one dowel-end is seen by the end user of the device and I would like to find some dowels with one nice finish end.

Most all dowels are crowned or beveled at the ends, but I am having trouble finding some that have a real nice and consistent looking finished end. I don't think a "bullet nose" dowel will work for this particular application & I am hoping to find a standard dowel that has a nice looking end.

I need a length of 1.5" and diameters of 5/16" and 3/8". The dowels should preferably be hardened.

I am hoping someone may know of a brand that may work for me.


Thanks for your help.

Sincerely,
John

 

[FredGarvin]

I guess you're going to have to be more specific when it comes to the asthetics of what you're looking for. I did a quick look for locating dowels on McMaster-Carr and they all look good to me (as far as locating pins are concerned). If you can be more specific you might get a bit more help.

 

[John2002]

Hi Fred,

Thanks for your reply.

The Mcmaster carr dowels are not what I am looking for as far as aesthetics go. It is hard to tell by looking at pictures in most catalogs what the dowel ends will really look like when you get them.

The Mcmaster carr dowels have one end that is slightly beveled (but not cut flat) and they have one end that is slightly rounded on the outer edge (but slightly concave in the middle). There are also black "dots" at each dowel end that look like some type of oxidation.

I only need one end of the dowel to look good, because only one end shows on the device.

I would like to have one end that is either crowned in a reasonably consistent manner (i.e., all of the crown should be convex and no part should be concave), or I would like to have one end that is cut off straight and flat with a reasonably consistent bevel.

Actually, if one end were just cut off straight and flat, and were reasonably smooth (like something that has been precision sawn), this could also work. I would like to stay in the price range of a standard dowel pin and not get into hardened shafting.

All the dowels seem to look nice in catalog pictures, but when I get them, they do not seem quite good enough for the application.

I am hoping that someone has possibly used a brand of dowel that has a nice finished end that may work for me.

Thanks again,

Sincerely,
John

 

[John2002]

Fred,

Regarding my last message, The dowel that I actually saw from Mcmaster carr is part # 98381A587, which has a 1/4" diameter, but I figured that the 5/16" and 3/8" diameters would look the same at the ends.

I also contacted Mcmaster carr and got the impresssion that they all look the same.

I am looking for a dowel like the Mcmaster-Carr 98381A546 (5/16" diameter X 1.5" long) but with an end like those described in my last message.


Thanks
John

 

[arto]

Try these guys:

http://www.reidproducts.com/standard_oem.htm

all kind of pins, dowels mil-spec & AN stuff

 

[ietech]

Hi John2002,

Unless the dowel pins you need have special properties, why not use a button head rivet as a dowel (stainless steel, aluminum, ete. etc almost any material in any hardness you can imagine). Rivets are very consistent in appearance - especially the button head variety.

They can be found with equal physical properties and dimensions to dowels and might solve your appearance problem. After all dowels are not rocket science.

Just a thought

Good Luck

ietech

 

[ietech]

Regarding my previous post: If you are using these dowels as alignment or pilot pins then my rivet suggestion will not work. but if they are just used as decorative fillers for holes then it will.

ietech

 

[John2002]

Hi Arto and Ietech,

Thanks for your messages.

The dowels do serve a mechanical purpose and I must use a dowel 1.5" long with a diameter of 5/16" or 3/8". The dowels have a slide fit in very close tolerance holes, and I do not think that rivets come with a + 0.0002" /- 0.0000" or a +/- 0.0001" diametrical tolerance like a dowel, (at least I have not seen rivets like this, but if they exist and are cost effective like a dowel, it would work good). Also, I prefer the dowel (or whatever is used) to be hardened.

The site from Arto looks interesting even if it turns out they don't have the dowels I need.

Thanks
John

 

[ietech]

Try this one the tolerances are pretty close.

http://www.fastenershq.com/keyword_Dowels.html

 

[ietech]

The link I sent in previous post ends up at Thomas Register --- The company I was trying to direct you to is the Mapco selection. Their stuff looks pretty good

 

[cncprogrammer]

John,

After reading this thread I guess I don't understand why you can't just grind one end. Simple, quick, cheap, you could even grind a chamfer with a little more trouble. How many pins are you talking about?

David

 

[John2002]

Hi David,

Thanks for your message.

Initial production runs may require 100 to 200 dowels.

Can you give me a rough idea as to how much the grinding operation would add to the cost of the dowels? Could 10 pieces for prototypes be done at reasonable cost or would this just be to low of a quantity to consider grinding?

I have been told that most high volume dowels are impact cut-off, which gives them the sheared look. The impact cutting does not produce a real flat or consistent end. If the stock dowels were just a little better, I would have no problem using them in this application.

Even though it is possible to grind the ends a stock dowel, I was hoping to find a stock dowel that already has ground ends from the factory, to avoid the extra step of having to get the dowels ground after I buy them.

Thanks again,
John

 

[cncprogrammer]

John,

The grinding should be realatively cheap. In the neighborhood of $1 or less per pin. If I were to do a couple of 100, I would make a simple jig from a block of fairly flat mild steel, perhaps cold roll. The jig would have rows of reamed holes to hold the pins, say 25 at once, and use a surface grinder. This covers the flat end. The chamfer would be substantially more as it would pretty much be a one at a time operation. I don't have access to a grinder or I'd do them for you at 200 for $.50 each flat ends only. Ten pieces would probably put you at the choosen shop's minimum job rate, normally 1.5 hours in this area at $45 an hour. So, getting the 200 would be close to the same price. A mom and pop shop would be your best shot.

David

 

[John2002]

Hi David,

Thanks for your reply.

If I can get one nice flat ground end, I don't think I really need a bevel.

I think your idea to use a jig to grind several dowel ends at once is the way to go if I cannot find a stock pin that comes from the factory with a nice flat ground end.

Thanks
John

 

[FredGarvin]

I'd be a bit leary of not having a chamfer on the mating end, especially since they are for alignment. Just my opinion there.

I see what you mean now about the asthetics. I guess I never put that much thought into dowel pins. I think the grind operation may be your best option.

Good luck.

 

[funnelguy]

Find a grind shop near you with double disc capabilities. They may already have a fixture or be running a similar part. This option really only applies to high volume work, but I'd be willing to bet the price would be something like a $75.00 set up and maybe .05 per pc. Do a little research, maybe the break point would be lower than I think.

 

[charlie300]

Usually dowel pins are hidden (pressed/slid into holes), which is why most people don't worry about their appearance.

May I suggest looking for Shafting instead of dowel pins. It is more asthetic, comes hardened, ground precision, and the ends are most often cut/chamfered precisely. You may have a problem finding small diameters and short lengths stock, but try Small Parts Inc., Berg, and Mcmaster.

 

[ornerynorsk]

You will find that metric dowel pins are finished differently on the ends than English standard pins. You might want to order a sample to see for yourself.