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small.planes
04-03-2009, 04:44 PM
evening all,
Its possible Ive imagined these... I cant find them with a google, but maybe Im looking for the wrong thing :confused:

I need an insert, which is threaded on the outside, and also inside. I need to install it in a plate, which is then inserted into a tube, and then bolted through from the outside. The outer thread allows the height of the insert to be varied (and thus the plate clearance to the tube wall) by screwing it in and out from through the hole it eventually gets bolted to. I think they have an allen key type hole in the bottom of the thread.

hopefully thats clear....

any Ideas if I imagined these, or what they might be called?

cheers

Dave

SGW
04-03-2009, 05:28 PM
No idea, and I can't visualize them from your description...but I'd check www.mcmaster.com as a possible source.

Opps - I see you're in the UK. At any rate, McMaster might tell you what they are.

small.planes
04-03-2009, 05:45 PM
Hmm, better description:

Imagine M10 rod on the outside, tapped M8 internally, about 6mm or so long, and then last 2mm internally is 4mm hex broached hole.

This can be screwed into / out of an M10 hole, using a 4mm allen key, but then once set in height an M8 bolt can be screwed into it.

Dave

J. R. Williams
04-03-2009, 05:48 PM
Dave
Check the net for "Re-Nu" threaded repair inserts. MSC has them in their catalog. The outer thread has a small Nylon insert to prevent removal.

JRW

small.planes
04-03-2009, 06:00 PM
yes, just like that, but I need to be able to change its depth using an allen key (or similar) through an (in this example) M8 clearance hole from the other side of a plate...
I thought Id seen some inserts like this, but maybe not...

Dave

Rustybolt
04-03-2009, 06:33 PM
helicoils. How many and what type do you need, I'll see if we have any around.

bob ward
04-03-2009, 07:05 PM
Internal and external thread cap screws with an allen key drive are quite common in the air cylinder world.

The external threads are typically used to secure the end caps to the barrel, the internals are used for the mounting plates.

oldtiffie
04-03-2009, 07:58 PM
Why not do a simple sketch with text - by hand will be fine - and then scan/photo/pics and then post it to Photobucket and then post the link to this thread.

Shouldn't take more than a few minutes and will assist greatly.

franco
04-03-2009, 10:15 PM
Is this what you are looking for?

http://www.practicalmachinist.com/vb/showthread.php?t=177774

If so, there is a supplier's website given in the last post on the topic

franco

Ernie
04-03-2009, 10:52 PM
They are called "threaded inserts". One source would be woodworking supply stores, on-line or in person. If you have a store nearby, I would go in person so you can see just what you're getting. They come in a variety of styles and material to suit the material you'll be driving them in.

Ernie

Evan
04-03-2009, 11:17 PM
Make one from a socket head cap screw. Turn the head down to 10mm OD and drill and tap an 8mm hole through the socket. I do it to rescue stripped threads. You will need a good quality tap.

Rustybolt
04-04-2009, 07:54 AM
We just do hreaded inserts without the hex. Run it up on a screw then screw it in the hole,. McMaster Carr probably has what you are looking for.

small.planes
04-04-2009, 10:24 AM
Ok, Ive knocked up a quick sketch of what I need:

http://i306.photobucket.com/albums/nn274/small_planes/Insertthingy.jpg

Making them for the prototype is ok, although I need 24, but this is for a production item, so Id prefer to buy them (or another solution) really

I need to be able to control the inner standoff distance without havign any access apart from through the M8 clearance hole.

cheers

Dave

Evan
04-04-2009, 10:41 AM
Do you have a plan to keep the adjustment from changing when the fastener is wound into the insert?

small.planes
04-04-2009, 11:30 AM
At this stage threadlock.
These are only adjusted on assembly, so screwing them all the way in with threadlock on, sliding assembly into a tube, and then screwing them out to adjust (only about 0.5 - 1mm probably), waiting for the threadlock to set and then completeing the bolt down is the current plan. how well that works remains to be seen....

Dave

Evan
04-04-2009, 11:49 AM
I would talk to these people. They are pretty close to what you need already.

http://ixian.ca/pics6/tsert.jpg

http://www.longloklocking.com/

nheng
04-04-2009, 01:48 PM
These have a slotted head and could be adjusted with a screwdriver tip that fits or is made to fit them.

It's a good thing you're small.planes 'cause if you were large.planes I'd suggest you find another way :D Den

http://www.ezlok.com/images/InsertsMetal/CarbonInsertsHero.jpg
http://www.ezlok.com/InsertsMetal/carbonSteel.html

Rustybolt
04-04-2009, 02:15 PM
These have a slotted head and could be adjusted with a screwdriver tip that fits or is made to fit them.

It's a good thing you're small.planes 'cause if you were large.planes I'd suggest you find another way :D Den

http://www.ezlok.com/images/InsertsMetal/CarbonInsertsHero.jpg
http://www.ezlok.com/InsertsMetal/carbonSteel.html


That's us what coats those.

Ernie
04-05-2009, 01:51 AM
I'm not very familiar with metric sizes but if the OD is 10mm with an 8mm ID, that only leaves a 2 mm difference, or a 1mm wall thickness. Is that thick enough to have both internal and external threads? Seems like you need more room than that or it would have to be a very fine thread???
Ernie

oldtiffie
04-05-2009, 02:21 AM
As a guide, the tapping drill for M10 is 8.5mm - as Ernie says, there is not a lot of "room".

I too have been wondering about this from the start, but said nothing as I thought I was missing something - perhaps I still am.

Tobias-B
04-05-2009, 04:02 AM
'improved patent peg inserts' in the stage world...
but the outside has a spline thread to bite into a hardwood stage deck.
They're typically slotted at the top so they can be driven with a flathead
screwdriver. This sort of thing you could make with a lathe...

but I agree, m12 and m8 would be a better combo...

t

small.planes
04-05-2009, 03:10 PM
Yes, looking at it M10/M8 probably wouldnt work. I havent really looked in detail at this (can you tell? :rolleyes: ) because I only had the idea on friday night, and its still the weekend.

cheers for all the ideas.

Dave