Bending sheet metal brackets

Sunday, July 6th, 2014

Here’s a nice example of using custom made CNC bend tooling to form bends that would be too small with normal air bending V dies.

Sheet metal bracket blanks produced by CNC punching

This small bracket has a couple of features that are of interest before we even consider the processes needed to bend it up. A bracket like this can be made with press tooling but the volumes need to be high enough to justify the initial cost of the hard tooling. The volumes and repeat period for these brackets perfectly suited CNC punching and CNC bending. When considering CNC punching these brackets we were able to use a standard circle and square from our Trumpf punch press tool library, so at no cost to our customer. The U shaped feature is created using 2 hits with a L shaped tool, this helps to make a stronger die and was suggested by the tooling department at Trumpf who we are always happy to work closely with. The complete outer profile for the blank was punched down one die on the CNC punch press allowing us to produce a clean part with 4 corner rads and very quickly.

Double bend CNC press brake tooling

Once we have a CNC punched blank part we can form in 3 small bends that are too close to each other for us to bend with normal standard library tooling. The distance between each bend was only a couple of mm so had to be formed in and coined up in one go. Again we worked with Trumpf’s tooling department giving them accurate CAD data of the final part wanted and free issued them with a number of blanks from the correct material and gauge so that they could experiment and fine tune the final results from the press brake tooling before hardening it.

The tool was supplied from Trumpf with all the tool data needed to load it straight onto our 7036 press brake and register it’s form within the tool library ready for CNC programming.

As an aside you can see the rear back stops with the corner ears cut out. This is a feature on both of the back stops that allows us to fit in tricky shapes at time when a plain flat back stop wouldn’t be possible. You can also see a red cross shape, this is the red light from the laser guard hitting the side of the tool while we set up the machine. The laser guards allow us to get in much closer to the machine than older light guards allowing a quicker operation of the machine and a more comfortable position for the operator to be in, which is so important on longer runs of parts.

Standard CNC bending tooling

Once the sheet metal punched blanks had the triple form feature pressed in and another standard 90 degree bend on the Trumpf 7036 we had to transfer them to one of our Guifil CNC press brakes for the final tight bend. We have some press brake tooling that we had specially machined back for another job in the past and this was perfect for forming this tight double bend. If you click on the image you will see how thin the end of the tooling is but very little tonnage is needed to form over the thin gauge zintec so it was quite acceptable. You can also see that we separated the 2 bottom V blocks to produce a gap that the small U shaped tag would protrude into while being bent up. This was necessary else the tag would have been bent as well. It’s amazing how many different machines, tools and techniques are needed to manufacture what looks like a simple sheet metal bracket.

Finished sheet metal brackets

Well here we are with the finished brackets. They will be used to help support LED light fittings into a ceiling grid on a refit program on a number of sites.

If you have a sheet metal bracket that needs manufacturing and you are not exactly sure what can be achieved with sheet metal please give us a call or send your initial design ideas and we will be happy to help you refine your designs and produce a quote for you.

Tags: bracket, cnc bend, CNC punch, sheet metal, sheet metal bracket, trumpf

Laser cut sheet metal work

Saturday, June 28th, 2014

Laser cut sheet metal work

Laser cut 4mm mild steel brackets

These simple bent angle brackets are used to support speaker of walls. They have been laser cut in our Fareham sheet metal factory from 4mm mild steel using Nitrogen. Using Nitrogen enables the powder coating finish to be applied directly to the folded brackets without any other preparation. The advantage over CNC punching which we had used before to produce these parts is the edge finish is much cleaner, production is a lot quieter and we have managed to increase the yield on bracket blanks from the same sheet size.

3mm thick laser cut mild steel

Using a laser cutter obviously enables us to cut thicknesses of materials much higher than those using a CNC punch press. We can also process materials that are thin at high speed but we can also cut curved edges to a very high standard. Any internal circular profiles or edge outer profiles can be cut with a continually changing movement if needed with no breaks in cut. This leads not only to a very pleasing component shape but can often leave us with no edge deburring to have to do. These sheet metal parts are covers on a piece of scientific equipment.

Laser cut thin mild steel sheet

These 0.7mm thick mild steel light fitting front frames are at the high speed end of laser cutting. Our Trumpf 3030 3KW fibre laser is perfectly suited to flying through any holes or profiles in this gauge of material. The edge finish is perfect and we have the added advantage of being able to cut these parts just with compressed air as the cutting assist gas. This helps to keep the cost down on the final sheet metal component. The frames cut here have a large window cut in the middle and this enables us to cut other parts from the scrap material again helping to keep the cost down on the set of parts.

Tags: bracket, laser cutting, sheet metal bracket, trumpf

Sheet metal work projects, June 2014

Saturday, June 14th, 2014

CNC punched Zintec brackets

CNC punching is so important to V and F Sheet Metal. Even though we have now installed a new Trumpf 3030 3KW fibre laser cutter we still process the majority of our sheet metal work through our Trumpf 200 and Trumpf 3000 CNC punch presses, these parts being typical of the small sheet metal brackets that we manufacture everyday of the week. The parts that need to be CNC punched may be thinner material, have a simple shape, need forms such as louvres, dimples, countersunk forms etc whereas the laser cut parts may be thicker or need more complex profiles that we don’t have a CNC tool for. There is however a great overlap on parts such as these zintec brackets shown here where they can be either CNC punched or laser cut and this gives us the flexibility to move jobs around in our factory to suit the loading on any machine on the day that the customer needs that order.

Aluminium light fitting chassis

These aluminium alloy chassis components are used to support fibre optic light fittings in a small chandelier. They have been CNC punched out from 1.5mm thick aluminium alloy sheet metal with all the outer profiles de-burred to remove any sharp edges and then folded up on one of our Trumpf 7036 CNC press brakes using a program stored from the time before speeding up production. The batch of 30 off was the second time that we have manufactured these parts and as the design hadn’t changed we were able to go straight into manufacturing and the batch was completed in just 3 days.

3mm mild steel laser cut housings

Large mild steel wedge shaped housings manufactured from 2mm and 3mm thick sheet metal. These parts fit together to make a housing used on a new tram system. The customer only had 10 days to get these parts from the point of giving us the enquiry as a new supplier to them. We produced 3D models in our Radan sheet metal software, developed the blank forms, laser cut samples and bent them up to check out everything before running the production batch. The batch of 50 parts were made in 2 days once the samples had been approved and shipped overnight direct to their factory in Yorkshire.

Tags: CNC punch, laser cutting, sheet metal, trumpf

Sheet metal welding fabrication

Saturday, June 7th, 2014

Here’s a great example of the aluminium sheet metal welding that we have carried out on some projects in June 2014

: Aluminium welded fabricated assemblies
Aluminium assemblies made from folded and rolled sheet metal work MiG welded together.

: Aluminium welded fabrications
Good examples of aluminium MiG welding to fix location tags in place underneath a chassis plate

: Aluminium housings with front covers
Aluminium housings folded and welded with covers.

These aluminium sheet metal fabrications shown are at various stages of completion with the housings on the right TiG welded, cleaned up and orbital sanded ready to go off to powder coating. The assemblies in the middle and on the left have been aluminium MiG welded. This process is not as controllable as TiG welding but much quicker and with our new aluminium MiG welding set we have been able to speed up the welding process on a number of fabrication projects.

If you want to see more examples of welding please take a look at our plant page welding fabrication proceesses

Tags: sheet metal, sheet metal fabrication, welding

Laser cutting and CNC punching working together

Monday, June 2nd, 2014

Laser cutting and CNC punching working together to produce the correct part

Laser cut sheet metal nest

Here’s a components that started off being CNC punched out on one of our Trumpf CNC punch presses. All the holes, outer profile and CSK formed holes were CNC punched in with the only problem being the amount of deburring and cleaning up we had to do before the parts were suitable for powder coating.

Once we had installed a brand new Trumpf 3030 fibre laser cutter we were keen to try it on existing CNC punching jobs and this one seemed an obvious candidate. Laser cutting through 3mm mild steel was no problem for the laser and the edge finish produced using nitrogen assist gas was much better than the one we had achieved with the CNC punch presses. The only problem was that we didn’t want to have to drill in the CSK holes so we had to find a way of getting the CSK forms back onto the CNC punch presses but still maintaining the perfect edge quality from the laser cutter.

If you click on the image of the laser cut sheet you can see the chassis panels with a large circular cut out and within these circles smaller components have been cut out for the same job. Some have fallen through the laser bed slats and will travel along a conveyor belt under the machine and be collected in a parts bin. Some have stayed on top of the bed slats and can easily be collected by hand at the end of the cutting cycle.

CNC punched CSK forms

To produce CSK forms in a sheet metal chassis that had already been laser cut we had to produce a jig that could accurately position the chassis panel in the CNC punch press clamps. The jig has to be able to freely move under the CNC punch head while supporting the component. Once this was done it was easy to program in the positions for the CSK to be formed and the job was done.

In conclusion I think it’s clear today that a manufacturing company needs not only to offer a wide range of production processes but the ability to integrate them correctly to produce the best parts to fulfill their customers expectations of quality, price and delivery.

Tags: CNC programming, CNC punch, laser cutting, trumpf