Mai 2016
The brake drums reconditioning
Today we are here with our friend Mario Finocchiaro of www.tecnomeridionale.it.
Mario is an high skilled technician and qualified seller in the garage equipment industry and historical distributor and expert of all Comec products.
Thanks to his knowledge, he will drive us into the brake drums reconditioning issue and the the related processing techniques.

Goodmorning Mario, could you explain us when should be appropriate reconditioning a brake drum instead of replacing it?
Goodmorning, now more than ever should be necessary turn the drums, until is physically possible, cause too many times are mounted drums of dubious origin, wich no completely respect the required quality parameters, at the detriment of security.
For this reason, most of the times, new drums are turned as well before mounting.

Wich kind of operation wee have to perform to reconditioning the drums ?
For first we have to check the technical specifications dictated by the mother company and proper turning measures.
After that, according with the drum that have to be worked, we have to correctly mount the shaft on the lathe, accurately check the cutting tool, correctly set the tool holder bar, wich must have a maximum extension at around the braking area that we have to turn.

What are the best tools and how many materials we have to remove in order to obtain a correct finishing of the braking area?
As I told before it's really important to keep the tool as closer as possible to the working area.
The best tools for this kind of operation are those with the replaceable insert, cause of the greater hardness of the bit, respect of the brazed tools that may be too fragile.
Talking about the removing material, I normally suggest to position the tool aproximately in the middle of the braking area, and peel a little the surface, just to remove a very small part of the material.
After that, set the measure on the vernier of the handwheel and take the tool to the bottom of the drum. Increase then 0,1 mm at the measure you got and insert the automatic feed of the lathe up to the end of the working operation.
This procedure allow us to remove about the 80% of the material we have to cut, in one step only.
After a quick visual inspection, you can decide if perform the operation once again up to a complete finishing of the barking surface.

What you have to do in case of the tempered spots on the braking surface?
In case of the  tempered spots the best solution is the use of the combined support for boring bar and drum grinder that allows to perform first the cutting and than the grinding operation givin the opportunity to mount on it a specific drum grinder.
Drum grinder do what the tool can't do, I mean removing the tempered spot.

Wich economical benefits and wich braking performance the drum turning can give?
Well, here the question is a bit more complcate and should need a separate chapter, cause related to the drums thare also are the brake shoes wich need the same cure.
In fact these should be turned as well but maybe we can deep the issue in another article.
By the way, talking about the economical benefits, a good turning operation takes the vehicle to a better braking test, during the normally cars inspections
Furthermore we will extend the brake shoes lifetime due to a corrct and uniform tear of the brakes.
Increasing the braking quality we will have an economical save and a growth of the safety on the road.

In the range of products Comec, wich ones are suitable for this type of operation ?
The best of Comec products for reconditioning the drums of trucks and van is for sure the TR2000, high techonolgy concept machine but strong and sturdy as it useds. I personally consider the Comec TR2000 the best brake lathe actually on the worldwide market.
The TR2000 is supplied with a standard tooling that includes: 60 mm shaft for the cones, intermittent feed, strong bar and bar holder and a set of cones and spacer that complete the lathe for any operating needs.
In the Comec products you can also find the TR1000 (is an evolution of the glourious TR1500) wich can also turns lighter veichles and the TR470 more indicated for commercial vehicles or cars, wich complete the brake lathes range of Comec products.

We thanks Mario Finocchiaro of www.tecnomeridionale.it for the availability afforded and for the valuable advices about the brake drums issue.
For any further information you can write to comec@comecpn.com

If you enjoy the article, please share it on the social networks by using the proper sharing buttons above.