binding barrel bolt meets a carriage bolt

[JEK5019]

good day -

first off! i am not a machinist - so you will have to be a bt forgiving. :beguiled:

i have a dilemma - i am working on this design - and the intent is that the (green) cylinder is to freely roll when applied to a surface (like a pizza cutter.)

however - the binding barrel (blue) i sourced out at mcmaster-carr - i do not want to rotate. and i certainly don’t want to too tight as it will start to bend the channel.

it’s also critical that the ends have no drive - but a nice polished-finished look.

maybe an adhesive?

i came across google images - where i can see a binding barrel with a hex at the base (like a carriage bolt) i think this would work - right?

but i imagine it’s easy to drill the hole in the channel - but the hex shape not so?

so i am at a loss.

if you look at the reference in the yellow circle - the bolt is normally welded and then sanded off. i don´t like this look. (unless there’s a machine shop that could perform this with a better finish?)

what are my options in achieving this function?

best regards -

jón

[magicniner]

We'll call the "Binding Bolt" the "Axle" and call the bolt which retains it the "Bolt"
Simply make the hole in your channel to clear the Axle at one side and the bolt at the other, the axle will insert through one side of the channel and sit against the other, the retaining bolt will tighten and retain the axle without pulling the channel together.
Use a chuck or collet chuck to hold the axle end still and to tighten the bolt, a little medium strength locktite on the bolt thread will ensure it does not work loose.

[JEK5019]

ah! that's brilliant - thank you!

back to design :barbershop_quartet_

[JEK5019]

okay -

once critical detail, however - and that is hoping to have no drive at either end.

i came across this binding barrel that is press-fit. but i doubt that'll provide enough tension to hold in place.

also - if i decide to use a binding barrel with a drive head - i would prefer to be a thin head - but all the heads i looked at are bulky.

i'm using mcmaster-car / are there any other manufacturers that you can recommend?

cheers -

jón

256362563725638

[magicniner]

Make your own axles for your product, it's fairly basic lathe work.

[JEK5019]

i'm sure it is - however, this is a small smart in an overall design i am working on - if the design proves to be successful - i'll be needing to make approximately several thousand pieces easily!

custom work at that level wouldn't prove cost effective - so i am trying to manage ready-made assets, if possible.

[magicniner]

You need to step away from your fixation on a fastener designed for easy use in non-engineering applications, they don't make threaded Chicago Screws without driver slots because they need to be user friendly for their intended purpose, holding together books, material sample swatches etc.
Use a length of tube with two press-in ends.

[JEK5019]

indeed.

my primary concern is movement. is there an epoxy that i can use where the tube meets the channel?

[magicniner]

indeed.

my primary concern is movement. is there an epoxy that i can use where the tube meets the channel?

To do what? You don't have the area to securely bond the tube to the channel with epoxy so why would you want to put epoxy there?
Tube
Holes in the channel the same size as the tube ID.
Hammer Drive Screws
Job done.

[hanermo2]

A peen, aka pin punch on one corner of the flat blue bolt flat area will mostly lock it in place.
This can be done in an inside-supporting fixture, think fork, avoiding distorting the U shaped hold.

Any industrial epoxy will fix the blue bolt, depending on load and the size of the end plate surface area.

A fast small drill through the holding bolt edge (blue), and a pin, punched, would also work.
So would e.g. blind pop rivets.

Press-fit barrels would definitely work.
Both for holding them, and the ends pressed in.
They need precise holes for press-fit purposes.
Think reamed to 0.01 mm in D, more or less.

Typical std reamer accuracy (0.01 mm in smallish D), easy to do, cheap, fast.

Custom barrels are probably much cheaper than anything like that from mcmaster in qty 3000 units.

Typically, mcmaster/misumi/etc cost 1-2-3$ for engineered units of any precision.
Industrial epoxy will likely cost 1$/unit, +/-, in small quantities.
Total 4$, or so, qty 3k total.
Plus lots of work in assy, several $ each. You cannot assemble 60 per hour.

You could get 3000 units of barrels and fitments and an assy jig (pop/rivet/pin) made by any jobshop for around 10k$.
And maybe a drill-jig to make the forks yourself.

[hanermo2]

Further, drill-rod as barrel, drilled and reamed and a secondary drill-rod as the endcap pressfit would likely cost about 2$/unit qty 3000.
Advanced lathes run 250$/hr and should put out 240-300 pieces / hr.

This would be a dead-easy job where lower unit costs are available.

[magicniner]

To repeat myself because it's the quickest, simplest, cheapest and closest to requirements.
Tube axle (fully inside the bracket)
Holes in the bracket the same size as tube bore
Hammer Drive screws will then fix the tube in place and prevent it rotating, drive screws don't require close tolerances for a good fit, definitely no requirement to ream, just drill.

[cropwell]

I have got a wallpaper seam roller in the garage, I will see how that is done.

[JEK5019]

okay -

so this seems like a viable solution. however, i would imagine that after pressing in the drive screws - they would probably 'slighting' bulge the inner tube - thus creating friction for the center barrel to rotate smoothly?

is this correct?

25648

[JEK5019]

i should also add that these pieces are quite small - that center hole is 0.4 cm. i would need a ID tube of 0.4 cm with a reasonable wall thickness to prevent bulging?

is something that small even available?

25649

[cropwell]

It would help if you could give us an idea of what you are trying to achieve. I respect that you may not want to disclose the end use, but some indication of the forces involved may be useful. Also is the axle to be free to rotate in the yoke or must it be definitely fixed? Are you looking to scale up to produce many units, or are you making just one or two? What material is the roller? Will it be wet (aqueous), oily or dry in end use? Do you have a unit cost limit in mind?

If you wanted a quick bodge you could pop rivet a length of tube into the yoke.

BTW cm is not a preferred unit in engineering, metric users prefer mm. In the US they use inches a lot (but not excusively). Some of the Model Engineers in UK use imperial measure, while some of the absolute recidivists use Furlongs, Newtons per square fortnight, Firkins and Ducats per gross.:teapot: Oh! and BA screws.

[magicniner]

okay -

so this seems like a viable solution. however, i would imagine that after pressing in the drive screws - they would probably 'slighting' bulge the inner tube - thus creating friction for the center barrel to rotate smoothly?

is this correct?

25648

No, it's not.
Drive screws have a fast outer helix with a relatively high sharp profile, they are designed specifically for blind holes where the relative sizes can be chosen such that material distortion stays local to the hole walls, among other things they are commonly used to fix data plates to castings.
You could make the holes in the bracket a tighter fit to give a lot of hold and the hole in the tube the right size to prevent rotation and give adequate retention without distortion of the outer.
It's your job to experiment with drive screw size, tube hole size and wall thickness to get the materials behaviour you require for your application.

[JEK5019]

so i am in total agreement with you - and in fact, the attached image i posted yesterday was according to your idea.

the only question i had - was would the drive screw slightly bulge the tube axle?

[JEK5019]

thanks magicniner. i guess it is a matter of experiment - much appreciated.

i'm currently using mcmaster as a source for stock items (as it allows me to drop in the actual 3d product into fusion 360 - enabling the design) however, their tube selection seems rather marginal.

do you have recommendations for manufacturers for smaller sized metal tubes?

[JEK5019]

thanks cropwell.

so i looked up the wallpaper seam roller you had mentioned - and the design i am working will work just like that, in fact! but unlike many of the designs, i came across - where the roller bracket is on one side only - my design will be built like an axle.

attached are several of these wallpaper seam rollers that more or less fit my goal and operation. :encouragement:

in my design goal - i am wanting to avoid any welding/sanding finished. i would prefer fasteners - but with no drives. very clean!

25652

25653

[JEK5019]

so the handle will be metal/wood lather operation.

the channel/bracket and the roller - all metal. no plastics.

the approximate pressure and use will be similar to that of the wallpapaer seam roller.

and lastly - if i can resolve this issue in the design and move forward - the goal will several hundred units at first. if i can market it well and proves successful - then definitely a few thousand thereafter.

░

also - i am living in iceland and it'll be costly to manufacture here. i am beginning to source out manufacturers throughout europe and states. i need to start some cost estimates

do you have recommendations for any machine shops to contact?

[cropwell]

Maybe a domed starlock washer, which would push onto a solid shaft, would fit your requirements.

[JEK5019]

this looks impressive. i guess my only concern would be - if you accidentally dropped the tool, say onto the floor and the floor met the roller - would these things just pop right off?

if not, then these might actually do!

[JEK5019]

Maybe a domed starlock washer, which would push onto a solid shaft, would fit your requirements.

but wait - the solid shaft needs to adhere to the channel - no motion - only the roller opertates.

that's where the drive screws came into the conversation. :welcoming:

[cropwell]

this looks impressive. i guess my only concern would be - if you accidentally dropped the tool, say onto the floor and the floor met the roller - would these things just pop right off?

if not, then these might actually do!

In my experience you have to destroy them to remove them. If you want the shaft to be fixed solid then your solution lies elsewhere.

[magicniner]

thanks magicniner. i guess it is a matter of experiment - much appreciated.

i'm currently using mcmaster as a source for stock items (as it allows me to drop in the actual 3d product into fusion 360 - enabling the design) however, their tube selection seems rather marginal.

do you have recommendations for manufacturers for smaller sized metal tubes?

For prototyping buy 1m to 3m lengths of tube with a slightly smaller hole than you think you need. Cut to length yourself with a hacksaw, holding the tube in a vice, use masking tape to mark the length, wrapping tape around it makes it easy to mark a straight 90 degree cut, cut slightly over length and file to size.
You can use a hand drill to open the hole up if required, once you have a definite set of dimensions ask for quotes from machine shops in your country, you're into a minimum 1000 parts so it's viable for professionals to quote.
Avoid getting too caught up in being able to download part models to build your product in CAD, model the tube yourself and have it made once you've prototyped it and have working dimensions.

[magicniner]

https://www.aliexpress.com/item/1-Pcs-Wood-Stainless-Steel-Flat-Pressure-Roller-Leather-Blank-Holder-Device-Hand-Push-Roller-Hand/32750710444.html

https://www.braunerequipment.com/product/steel-seam-rollers

https://www.ajctools.com/AJC-2-Steel-Seam-Roller-Prodview.html

?

[JEK5019]

A peen, aka pin punch on one corner of the flat blue bolt flat area will mostly lock it in place.
This can be done in an inside-supporting fixture, think fork, avoiding distorting the U shaped hold.

Any industrial epoxy will fix the blue bolt, depending on load and the size of the end plate surface area.

A fast small drill through the holding bolt edge (blue), and a pin, punched, would also work.
So would e.g. blind pop rivets.

Press-fit barrels would definitely work.
Both for holding them, and the ends pressed in.
They need precise holes for press-fit purposes.
Think reamed to 0.01 mm in D, more or less.

Typical std reamer accuracy (0.01 mm in smallish D), easy to do, cheap, fast.

Custom barrels are probably much cheaper than anything like that from mcmaster in qty 3000 units.

Typically, mcmaster/misumi/etc cost 1-2-3$ for engineered units of any precision.
Industrial epoxy will likely cost 1$/unit, +/-, in small quantities.
Total 4$, or so, qty 3k total.
Plus lots of work in assy, several $ each. You cannot assemble 60 per hour.

You could get 3000 units of barrels and fitments and an assy jig (pop/rivet/pin) made by any jobshop for around 10k$.
And maybe a drill-jig to make the forks yourself.

i totally missed this post - terribly sorry about that!

very invaluable information here on the process. additionally, if you don't mind - i would like to contact you via message. :nevreness: