26 Replies Latest reply on Apr 27, 2018 10:27 AM by Kevin Chandler

    Methods of marking/etching components for positionning

    Alex Lachance

      Hello,

       

      We are currently in the process of trying to find ways to optimize our production. One of them was to find a way for the welders to be able to place parts without having to get their measuring tape out.

       

      We've looked at inkjet marking, laser etching, we've tried having positioning points both at the bottom and at the top of the flange so that it would give us the angle of positionning at the same time.

       

      Inkjet was way too intensive, it was pretty costy too.

      Laser etching seemed like what we wanted at first, until we started piling up some components outside. The rain and casual humidity made the steel rust a little bit and because of that the laser etching wasn't seeable anymore.

      Positioning points was also looking well. The problem we encountered with them was pretty much the same as Laser etching. Either the guy would forget to mark the web with a chalk before welding the beam together or he would mark it and the beam would then be transported 300 miles further away at another shop of ours where the chalk mark would then have disappeared. This is the positioning points I speak of:

       

      So my question here is, does anyone use any method of marking/etching? If so, what do you use, have you tried any other methods? Why haven't you gone those other methods? The intent here is to facilitate the workload for the welders by avoiding them to have to pull their measuring tape out.

        • Re: Methods of marking/etching components for positionning
          Kevin Chandler

          Hello

           

          Do you have a punch/laser combo or just the laser?

          We've done punching for decal location that was visible after powder coat.

           

          Is the material too thick for alignment using a through hole/semi-circular edge notch? Or would this sacrifice part strength?

           

          Cheers,

           

          Kevin

           

          EDIT:

          I see there are small holes at the right edge of the image.

          Are there enough such locator places where you can insert a small locator jig.

          Are the products too custom to warrant even such small jigs?

            • Re: Methods of marking/etching components for positionning
              Alex Lachance

              Hey Kevin,

               

              Glad to get your input as always. We currently have a plasma table at this shop and a laser at the other shop.

               

              The material we're looking to mark on is generally between 3/16 and 5/16''. The parts being placed on those marks are between 3/16'' to 3/8'' generally, but there are other products which use larger thickness, from 3/8 to 3/4.

               

              The products are generally very custom. The idea of the holes wasn't too bad, the problem is they weren't big enough so if we didn't mark them with a chalk, the welding would cover it up. Then came the weather problem because we lack storage room. Still working on cutting down the inventory...

                • Re: Methods of marking/etching components for positionning
                  Kevin Chandler

                  Alex Lachance wrote:

                   

                  Hey Kevin,

                   

                  Glad to get your input as always. We currently have a plasma table at this shop and a laser at the other shop.

                   

                  The material we're looking to mark on is generally between 3/16 and 5/16''. The parts being placed on those marks are between 3/16'' to 3/8'' generally, but there are other products which use larger thickness, from 3/8 to 3/4.

                   

                  The products are generally very custom. The idea of the holes wasn't too bad, the problem is they weren't big enough so if we didn't mark them with a chalk, the welding would cover it up. Then came the weather problem because we lack storage room. Still working on cutting down the inventory...

                  Hello again,

                   

                  The material did appear to be thickish in the image which is why I didn't mention tab/slot.

                  We use tabbing here when the need arises, but that generally doesn't apply above ~11ga CRS, not that it can't technically, it's just the diminishing returns kick in readily.

                   

                  What Would "thin" gauge locator plates work out, ones that can be quickly profiled out, clamp in place, then scrapped (if there's no current workload to support storing such)?

                  Have holes big enough to cold punch a mark through the jig plate into the stock right as the stock is on the weld table.

                  You could mark on the jig plates which part is located to what holes and add any other references that would aid the fabber.

                  Would this cost be offset enough by the reduced current tape measure time and by potentially less scrap rework?

                  These would be stored inside so they shouldn't scale too badly too fast. Plus, it's just a punch hole plate so a little oxide won't bother its function even if the stock's a bit extra scaly from being in the weather a bit.

                   

                  Cheers,

                   

                  Kevin

                    • Re: Methods of marking/etching components for positionning
                      Alex Lachance

                      Hey,

                       

                      I might have misunderstood what you meant as a jig. Our jigs are made in order to position our parts, they were made by the shop workers, so they made made them accordingly to the parts. Those are pretty heavy and time demanding to manipulate.

                       

                      What we didn't think of is what you said, thin gauge locators used to punch marks. On the other hand, those aren't heavy, they don't take up much storage space, they just need to be identified correctly, which isn't a problem here. That sounds like a great idea.

                       

                      Edit: Now that I rethink of it, not sure if it's a better idea then having the holes made from the plasma table.  Here's something we did, pretty much as tab and slots. We just never went further into it.

                       

                       

                        • Re: Methods of marking/etching components for positionning
                          Kevin Chandler

                          Alex Lachance wrote:

                           

                          Hey,

                           

                          I might have misunderstood what you meant as a jig. Our jigs are made in order to position our parts, they were made by the shop workers, so they made made them accordingly to the parts. Those are pretty heavy and time demanding to manipulate.

                           

                          What we didn't think of is what you said, thin gauge locators used to punch marks. On the other hand, those aren't heavy, they don't take up much storage space, they just need to be identified correctly, which isn't a problem here. That sounds like a great idea.

                          Hello,

                           

                          Sorry, I think I jumped the rails w/o indicating so.

                          Originally, I was thinking small, quick jigs/fixture used to located by/against, then removed when the part is tacked in place.

                           

                          In the second ramble, I was thinking of using a template (this is the wording I should have used).

                          Basically, a flat plate of a thinner gauge (14 ga/16 ga, cheaper/more manageable) as a template to guide where to place punch marks on the stock.

                          Similar to what you mentioned in the OP which was being obliterated by the weather.

                          Place this hole template onto the stock as it's on the weld table, abutted it to some edges, clamp it, prick punch through the template holes, remove the template.

                          Fresh markings to locate by.

                           

                          Is this a little less obtuse?

                           

                          Cheers,

                           

                          Kevin

                      • Re: Methods of marking/etching components for positionning
                        S. Casale

                        Perhaps at the plasma table you could use a machinist blue marker (DYKEM)  that's permanent? Write it in the routing workflow for the guy to mark the part.

                    • Re: Methods of marking/etching components for positionning
                      Benjamin Modic

                      Hey Alex,

                       

                      A little unrelated, but it may be very useful for you on your parts. New in SOLIDWORKS 2018, there is a new tab and slot feature that would help your fabricators position parts without the need for expensive fixturing. Check it out...

                       

                      2018 What's New in SOLIDWORKS - Tab and Slot

                        • Re: Methods of marking/etching components for positionning
                          Jim Steinmeyer

                          Alex,

                          If it will fit with your designs I would second what Benjamin Modic said. I have used tab and slot before and am now transitioning some of the weldments here. I have changed structural tubing to formed channel and placed tabs on one side of the channel in case it isn't formed exactly right. I then add a little gap between formed parts, again in case parts are formed wider than intended. with time studies so far we are saving about 1/3 of our weld time on what we have done before. Of course there is more fab time for some parts but it still saves time overall, you just need to be aware of your bottleneck areas.

                          In the past I have used the tab and slot concept in the 5th wheel plate and cribbage areas as well as for front and rear decks and toolbox brackets. (Ya, I've worked OTR too )

                          • Re: Methods of marking/etching components for positionning
                            Alex Lachance

                            Thanks for the heads-up Benjamin, I'm not on 2018 as of now tough. We will move to 2018 as soon as a little problem is fixed on our side.

                             

                            We use library features to place those markers as of nowand control them with sketch patterns. The tab and slot will be something we will definetly use for a smaller assembly that needs simplifying, if it does indeed work as intended.

                          • Re: Methods of marking/etching components for positionning
                            Paul Risley

                            The last shop I designed for this was a major undertaking.Tab & slot was used then laser etching. Since this was for food grade the tab & slot worked ok with a lot of excessive cleanup work needing to be done to remove pitting and such as this was all washdown equipment.

                             

                            In the end we went with holes cut at the same time the sheets were. Cut/punch the holes in 3 positions relevant to the edge of the locator piece. 3/16" or 1/8" is what we used. Drop dowels in bump sheets against them verify vertical squareness and weld. Remove dowel and fill weld, clean up and move on. It seemed to work pretty well. If I remember correctly you guys make trailers so the cleanup of the holes would not need to be an issue.

                             

                            I liked the tab and slot, and with 2018 it would be super easy to set up tolerance for both to be able to consistently keep your gaps controlled. I don't miss hand sketching those things for every piece.

                            • Re: Methods of marking/etching components for positionning
                              Dan Pihlaja

                              Do you use any sort of coating on this?

                               

                              Reason why I ask, is that some of our parts, we black oxide.  On those, we will sometimes have a post machining process where we will create some engravings, and they show up really well.

                               

                              Another option that we use sometimes is machine engraving, then filling the engraving with some sort of color. We use the Markal Painstik:

                              B® Paintstik® | Markal

                               

                              Of course, both of my methods require machine engraving....which may not be what you want.

                              • Re: Methods of marking/etching components for positionning
                                Casey Bergman

                                One thing that we do is put a tick mark on the edge of parts to indicate direction.  Below we have a rectangular opening and we put one tick vs. two ticks to show which side is different.

                                  • Re: Methods of marking/etching components for positionning
                                    Alex Lachance

                                    That is similar to a method we tried, ours were material removed inside the part instead of a tick outside of the part. The reason being that there is something over and under the part.

                                     

                                    The problem we encountered with them was pretty much the same as Laser etching. Either the guy would forget to mark the web with a chalk before welding the beam together or he would mark it and the beam would then be transported 300 miles further away at another shop of ours where the chalk mark would then have disappeared because of the weather. And by then, the ticks have been covered by the welding of the part under it.

                                      • Re: Methods of marking/etching components for positionning
                                        Casey Bergman

                                        Understand, that is part of our reason is that we do cover it with weld so it is not visible once completed.  You really need it to stay permanently right?  Have you thought about stamps?  Even if it is a series of centerpunch marks that you knew what it meant or have a custom stamp made that was what you wanted.

                                          • Re: Methods of marking/etching components for positionning
                                            Alex Lachance

                                            It can be covered with welding, that isn't really a problem. Our problem was that whatever we used to make the markings from those ticks would wear off from the weather. As of right now, we only tried chalk and permanent pen markers, which are not so permanent after all.

                                             

                                            We use custom slots and tabs sometimes, tough that is something I am trying to avoid as that would change flat bars that we use as stiffeners into plates that need to be cut on a laser/plasma table.

                                              • Re: Methods of marking/etching components for positionning
                                                Casey Bergman

                                                We might have our wires crossed here, we actually cut the notches on the edge of the part using our laser.

                                                  • Re: Methods of marking/etching components for positionning
                                                    Todd Blacksher

                                                    Casey Bergman wrote:

                                                     

                                                    We might have our wires crossed here, we actually cut the notches on the edge of the part using our laser.

                                                    I'm right there with you - We did almost the exact same thing for a big project a little over a year ago.

                                                    Think of a box with no lid, now make each of the sides different, and the orientation is critical.

                                                    The "bottom" of the box would get little "ticks" that were cut on the laser - 1st side gets 1 tick, 2nd side gets 2 ticks, and so on.

                                                    The "sides" of the box would get little "ticks" that correspond with the "bottom".

                                                    All of the "tick" marks were shifted to one side of the part so that the welders could just line up the corresponding marks, tack, verify, finish.

                                                    It was a HUGE undertaking, but this method totally saved us!

                                          • Re: Methods of marking/etching components for positionning
                                            Alex Lachance

                                            Thanks everyone for your input. Those are all methods we have tried besides the template one Kevin suggested.


                                            I will write back on here once we've implanted it to say which method we've gone with and try and explain it.


                                            Cheers!

                                              • Re: Methods of marking/etching components for positionning
                                                Kevin Chandler

                                                Hello,

                                                 

                                                I realized you've signed off on this for now, but here's a 16ga CRS template image to illustrate:

                                                In addition to holes for prick punching, you can add slots for scribing part placement edges, using for example: https://www.amazon.com/General-Tools-88CM-Tungsten-Carbide/dp/B00004T7S1?psc=1&SubscriptionId=AKIAILSHYYTFIVPWUY6Q&tag=d…

                                                Left to right:

                                                • Two 90° slot pairs for a square edge location.
                                                • Next two 90° slot pairs are also for a square edge location, but this part has a chamfer (which you don't have to scribe for), but this is one of those reminders, that I mentioned above, for the fabber to locate this part with the chamfer oriented as such.
                                                • The rightmost three slots are for a non-square part which would be difficult and misaligned if located by tape measure.

                                                 

                                                All part locations are scribed at the same time, so part-part variance is less and there's no measuring.

                                                Scribe, place parts, tap-tap to align edges, clamp, tack, weld per print.

                                                 

                                                The three holes are for ease in template placement.

                                                They're tapped holes for adding hex socket head cap screws (SHCS) as "locator pins".

                                                Insert the SHCS head down and secured them w/locknuts (whatever size you have hanging around.

                                                • Template face is primary datum
                                                • Two SHCS on long edge are secondary datum
                                                • Single SHCS is tertiary datum

                                                 

                                                I mention them as tapped instead of screw clearance through holes to reduce screw head position variance due to thru hole slop.

                                                 

                                                Cheers,

                                                 

                                                Kevin

                                              • Re: Methods of marking/etching components for positionning
                                                Kevin Chandler

                                                Hello,

                                                 

                                                I noticed various coatings/treatments are being suggested to prevent oxidation of markings.

                                                 

                                                However, I haven't read (coulda missed it) where you may have to add a cleaning operation if there's an issue with welding with any coatings.

                                                Like for black ox, there's an oil film that may need degreasing.

                                                 

                                                Cleaning for other coatings might even eliminate the underlying markings.

                                                 

                                                Ask your welders about coatings.

                                                Also check what would be off-gassed from the coatings from the weld heat.

                                                 

                                                Just throwing it out there for something to keep in mind.

                                                 

                                                Cheers,

                                                 

                                                Kevin