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hitachi230
18th Sep 2008, 11:25 PM
Hi all
Which is the strongest Loctite product for permanently joining steels? I have a collar I need to slide onto a shaft and fix there for good. It's location means that grub screws etc cannot be used so I thought Loctite would be the way to go.

TIA

Dave

pipeclay
18th Sep 2008, 11:42 PM
How much interference on the shaft are you expecting to have,the rule of thumb is .001 to the inch.
You mAY BE ABLE TO EITHER SHRINK FIT THE PART YOU HAVE BY PLACING IN FREEZER OR DRY ICE ORLIQUID NITORGEON OR MAYBE

AUSSIE
19th Sep 2008, 12:12 AM
Wouldnt you need to warm the collar up to expand it.Then quickly drop it on shaft.It then cools and is an interferance fit ,if machined properly ie .001 thou per inch or so.
Axle bearings on cars have been done this way and work fine

Keith_W
19th Sep 2008, 06:42 AM
hitachi230,
Good suggestions from AUSSIE and pipeclay, but if you are going to use Loctite suggest you look at this site for recomendations
http://www.loctite.com.au/int_henkel/loctite_au/index.cfm

Regards,
Keith.

Retromilling
19th Sep 2008, 08:48 AM
Wouldnt you need to warm the collar up to expand it.Then quickly drop it on shaft.It then cools and is an interferance fit ,if machined properly ie .001 thou per inch or so.
Axle bearings on cars have been done this way and work fine
Good point. I was always led to believe that cooling a circle of steel made its ID bigger but a test I saw recently showed the opposite.
Heating made a circle of steel bigger in the ID not smaller .
So I am still confused on this issue.
Thats it I am going to do the test myself .

joe greiner
19th Sep 2008, 09:09 PM
Heating most materials makes everything bigger, outside as well as holes. Heating the hub, and cooling the shaft, then allowing return to ambient temperature, is often used for securing the main axles of bascule bridges (approx. 16" diameter). This is generally permanent; removal is by demolition only.

Loctite is usually used on threaded connections, where there's plenty of contact area; heating can generally be used to release the grab. I doubt it would be useful for a simple shaft-to-collar application, unless there's a huge multiple of contact area.

Joe

Kody
19th Sep 2008, 09:36 PM
Axle bearings are NEVER shrunk onto an axle for a car or any other axle/machine. The heat would totaly destroy the bearing. The part that is shrunk on is the retaining sleeve. This sleeve is what stops the bearing from sliding off and keeps the axle from comming out of the housing.

If you are going to heat a collar to expand it, then the shaft is also put in a frig. or freezer if possible. It is essential that the shaft is stood vertical and fixed solidly. There must be a removable ring or collar or something that forms a stop for the hot collar to come to rest on as it shrinks. Be very careful to start the collar without it canting on the shaft or it will instantly stick and then stay there. The collar will need to heated to a dull red heat to enable the heat to remain as it is positioned on the shaft. It all happens very quickly so make sure everything is set up properly to go.

Loctite is wonderful stuff to use to lock parts together. It will work even better if the parts are totally degreased (from fingerprints and sweaty hands) and then fully sprayed with the spray can of cleaner that is made for the job. This stuff will set the Loctite off very quickly and you only have about 4 seconds to get the parts aligned before the Loctite sets. By cleaning the parts with the spray can, the strength of the bond increases immensely. I cant remember what the spray can is called but the distributer will know what it is.

Kody

Master Splinter
19th Sep 2008, 09:38 PM
Loctite make a range of bearing mount anaerobic adhesives, with Loctite Bearing Mount 680 being the strongest.

I first read of them in a book by Carroll Smith (I think it was "Engineer to Win") and he is quite happy to use and recommend a number of the Loctite products - and yes, he's been in teams that have won Le Mans as well as the Bathurst 1000, so I'm happy to take his opinion on the matter!

joe greiner
19th Sep 2008, 10:30 PM
There must be ... something that forms a stop for the hot collar to come to rest on as it shrinks. Kody

Right. This is the best way to assure alignment. Hopeless if not done.

Joe

AUSSIE
19th Sep 2008, 11:20 PM
[quote=Kody;810119]Axle bearings are NEVER shrunk onto an axle for a car or any other axle/machine. The heat would totaly destroy the bearing. The part that is shrunk on is the retaining sleeve. This sleeve is what stops the bearing from sliding off and keeps the axle from comming out of the housing.

I don't think anyone was suggesting heating the bearing.It was he collar that is heated.I did a few years working with electric motors ,alternators and bearings and my hobby was cars.There was a loctite that would lock collars or bearings onto worn shafts if needed.I think it was green ,but cant remember the number.Dont know if that is what it was meant for ,but it worked.

pipeclay
20th Sep 2008, 08:23 AM
Kody never say never ,there are quite a few instances where bearings are heated to allow fitment on to shafts and axles , (have never seen a flame used) more so Oil Bath Heaters and Induction heaters.

AUSSIE
20th Sep 2008, 09:06 AM
Yeh your right pipeclay.Oil bath or induction,no flame.Controlled temp.I didnt mention that as I thought it complicated matters when Hitachi230 only wanted to know what loctite to use to lock a collar on
Quote by HITACHI230
Hi all
Which is the strongest Loctite product for permanently joining steels? I have a collar I need to slide onto a shaft and fix there for good. It's location means that grub screws etc cannot be used so I thought Loctite would be the way to go.

TIA

Dave

Ashore
20th Sep 2008, 10:57 AM
Hi all
Which is the strongest Loctite product for permanently joining steels? I have a collar I need to slide onto a shaft and fix there for good. It's location means that grub screws etc cannot be used so I thought Loctite would be the way to go.

TIA

Dave
before we get too carried away, has the collar already been made or are you going to make it, will it be a sliding fit or an interference fit :?

Yonnee
20th Sep 2008, 06:09 PM
Interesting statement on the Loctite website though, that interference fit done with heat usually only make contacts with 30% of the surface area, whereas the liquid Loctites such as 'Shaft fit' & 'Bearing fit' give full 100% contact.

TomH
21st Sep 2008, 11:08 AM
I know you are talking about Loctite for securing a collar on a shaft, but here is some additional information. The following document gives shaft & hole sizes (i.e the deviation off the same dimension for shaft and hole) for the most common fits, from loose running fit through to heavy interference fit. This will give you an idea of the amount of interference required for a given fit.

http://www.misumiusa.com/CategoryImages/Metric_2006_pdf/METRIC1835-1836.pdf

We have used loctite at work instead of interference fits in some circumstances, but you really need to consider each application before deciding the best method.

Hope this helps in the future.

Tom

bollie7
21st Sep 2008, 03:05 PM
Hitachi
whats the application? large dia or small? do you nedd high strength? etc.
I reckon there will be a loctite product that will suit. Probably "super retaining compound 638 for max strength, 635 for slow curing or 680 for gap filling.

Loctite is great stuff, I've been using it for years. On smaller diameter stuff it is better than shrinking for most applications. Just remember to clean the tip of the nozzle when you have finished using it so it doesnt clog the nozzle.

regards
bollie7

Master Splinter
21st Sep 2008, 04:04 PM
With loctite - remember to follow the cleaning instructions to the letter if you want maximum strength - a wipe with an oily rag isn't good enough; spray-on brake cleaner works for me.

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