Maker Pens for tightened bolts

[timandchris]

I have seen several people recommend marking bolt heads to both show they have been torque tightened and to indicate if they are coming loose, tip-ex seems really naff are there any marker pens that people have successfully used on metal for this job?

Sorry for another stupid newbie question....

[Barry Ashcroft]

Would have thought a black permenant marker pen would do the job required.

[adamnreeves]

I have seen several people recommend marking bolt heads to both show they have been torque tightened and to indicate if they are coming loose, tip-ex seems really naff are there any marker pens that people have successfully used on metal for this job?

Sorry for another stupid newbie question....

I use one of those little tins of epoxy paint, the type used in airfix models! White is good. If you need to undo the bolt and remark you can chip the paint of with a screwdriver so that you can remark an alignment mark without looking confusing!

Btw, I have cleaned my threads, jobs a good-un. I shall drop the tap back within next couple of days. Thanks.

[nikpro]

Btw, I have cleaned my threads, jobs a good-un. I shall drop the tap back within next couple of days. Thanks.

I used a car touch up paint with a little brush included, like Adam says you can just clean it off if you need to remark.

PS  Have you dropped his wife off aswell Adam?  

[adamnreeves]

Btw, I have cleaned my threads, jobs a good-un. I shall drop the tap back within next couple of days. Thanks.

I used a car touch up paint with a little brush included, like Adam says you can just clean it off if you need to remark.

PS  Have you dropped his wife off aswell Adam?  

even better, less messy, good tip.

[DickieB]

I've used Tippex for years. Works fine. Get one of the pen type Tippexes not the brush type.

[Barry Ashcroft]

What about the one on the roller wheel  

[stu999]

Using a marker/paint pen to 'tag' fasteners as you tighten is a handy visual aid to ensuring all relevant bolts have been tightened - and nothing more.

I personally wouldnt recommend using the above as a visual aid to ensuring components are not working loose. IMHO this should *always* be done by a spanner check, because the clamping force of the fastener can end up being reduced without the fastener actually moving - as things 'bed-in' to their new homes...  

[zvezdochka]

I go for the belt and braces approach, car touch paint markers on less critical items but check safety related things such as suspension with a spanner / torque wrench. Using the wrench I set it at about 95% of the required torque on things like suspension bolts. After 3 months running was surprised to find about 20% had relaxed due to bedding in as stu999 post above.

On the other hand the bolts on the Lobro joints have not moved at all, perhaps as this is  a straight metal to metal joint whereas chasis has epoxy etc.

Rick

[budmikem]

If you go to an  general engineering supply company they sell 'paint pens' in most colours [white / yellow / red]

They have a roller top....and last for years...they are extensive used in marking steelwork etc.

If you want one...pm me

[tex]

as you know bolts stretch to hold together what parts they are holding together, the metal is under tension when correctly torqued off. its the tension that holds the bolt tight.

the only proper way to check that the torque stays the same over the life of the bolts use and to avoid torque 'drop off' is to actually measure it with a dial guage and keep a record of what it should be and what it actually is after a short time of use. i work inspecting new cars at a certain japanese plant doing such checks and torque drop off is a real problem - usually caused by incorrect torqueing of a bolt. it maybe the torque wrench is incorrectly calibrated or incorrectly used or simply something got in the bolt head when tightening up - but if you under torque a bolt it may work loose due to the lack of 'elastic tension' in the bolt and similarly it may be overtightened leading to the bolt going past its elastic tension point - then becoming brittle and liable to snap.. be warned -

good calibrated torque wrenches work best!!

bad ones mean shiny bits fall off..

[cast iron]

as you know bolts stretch to hold together what parts they are holding together, the metal is under tension when correctly torqued off. its the tension that holds the bolt tight.

the only proper way to check that the torque stays the same over the life of the bolts use and to avoid torque 'drop off' is to actually measure it with a dial guage and keep a record of what it should be and what it actually is after a short time of use. i work inspecting new cars at a certain japanese plant doing such checks and torque drop off is a real problem - usually caused by incorrect torqueing of a bolt. it maybe the torque wrench is incorrectly calibrated or incorrectly used or simply something got in the bolt head when tightening up - but if you under torque a bolt it may work loose due to the lack of 'elastic tension' in the bolt and similarly it may be overtightened leading to the bolt going past its elastic tension point - then becoming brittle and liable to snap.. be warned -

good calibrated torque wrenches work best!!

bad ones mean shiny bits fall off..

Loose bolts in the Trim shop not a problem in the Engine shop, I say sack the engineers!