Alternative to Shoulder Bolts

[extrudedfeature]

Hello All,

I am currently designing an solution that require the use of shoulder bolts. Now through my research and browsing I am amazed at the price of these things.
I have seen however people use a small 'collar' or 'washer' that essentially does the same job. I am however finding it very hard to find the name of the part or a similar product. Essentially i need a washer for an m6 bolt, that roughly 3-4mm deep and with a wall thickness of about 1mm.

If any would know the name of such a thing or where to find it I would be very great full.

Many Thanks!

 

[ajack1]

http://www.awp-ltd.com/downloads/AWP_UK_Tooling_Accessories.pdf

Various companies do manufacture them and they tend to be called 2 or 3 piece stripper bolts or calibrated tube stripper bolts, but I am not sure they are much cheaper.
Could you not just drill a hole in a piece of silver steel as an alternative?

 

[fegenbush]

If you require concentricity, a shoulder bolt is the way to go. They are ground concentric on the shoulder to a very tight tolerance. If you are looking for a washer, you can buy tubing in 1m lengths for $10 (USD) from McMaster-Carr and cut to length (Item# 50295K242). If you need more, the tube is available in 2m lengths as well, but I have found that is cumbersome to ship. I am also sure that you could find this locally.

 

[rb1957]

i think you can sub a bolt and sleeve bush for a shoulder bolt ... need to check it carefully though

 

[Cockroach]

I have done both, sleeved a Socket Head Cap Screw to a tight tolerance, and made my own specialty Shoulder Bolts. Depends on your design requirements, holding forces and application to the environment (inside working fluid, material chemistry, etc). If you want the less expensive solution, then as RB1957 has suggested. If you need the precision, then FegenBush can be referenced as above.

Regards,
Cockroach

 

[Jboggs]

Tread very carefully here. In my experience shoulder bolts are among the most commonly misused mechanical components. If incorrectly applied they can contribute to misalignment and binding. If incorrectly applied they can very easily break. If correctly used and applied they can be an ideal solution. I've never heard anyone complain about their price though, unless you're talking about using hundreds of thousands in the design of some commercial product. Usually they are much cheaper than the total cost of any substitute design.

Make VERY sure you understand ALL the forces involved in your application. The secret to successful application of shoulder bolts is absolutely in the details.

 

[extrudedfeature]

Hi jboggs, the load in on the part in this instance is very low, maybe 1-2kg. As for amount i would be looking at a production run of 500+ so price is important. From what i have seen they range from £2-4 per unit!

I know for sure that there is an alternative, I in fact have one to copy, however i cannot find the part anywhere. If i find time ill upload a photo and i'm sure people will know exactly what i want and where to find it!

 

[fegenbush]

If you're not in love with the 3-4mm shoulder length and can accept 6mm, they can be had very reasonably.

 

[mfgenggear]

fegenbush

a suggestion

why not use assembly fixtures to align & hold you details while assembling.
thus the elimination of shoulder bolts. the cost of tooling can be amortized into the large qty.

or use simple dowels to align the details.

Mfgenggear

 

[mfgenggear]

oops sorry that comment was for Extrudedfeature

Mfgenggear