Cutting relatively thick metal. Ideas needed.

[dbhost]

I know this isn't a woodworking project. But I was hoping you guys and gals might have some suggestions...

I picked up a winch for my lumber wagon, and I want to mount it behind the bumper, so that the fairlead (the thing that directs the cable) sticks out through a cutout on the plastic air dam on my truck. Access to the clutch / direction controls would be through the bumper slot I know...

Anyway the idea is like what this guy did with his, but mine is an '04, which means the bumper slot / lower grille opening is MUCH larger, and the driving lights are shaped different...


The guy took a Harbor Freight Universal Winch Mount Channel, which I see done pretty much the same on all the 4x4 and truck boards, and he cut sections of the 90 degree uprights out as in the photo below in order to allow the channel mount to sit flush to the frame of the truck.


What I am needing to know is how can I make these cuts, and deburr / smoothe this out so there are no nasty sharp edges to catch on anything important, like me, with the tools an average woodworker would have?

Or what can I use that can be bought cheap?

I do have some tools that will work that aren't normal woodworker tools. A die grinder with abrasive cut off wheels. I am concerned that would take forever.

I know several of you do agricultural type work, fiddle with motorcycles, or otherwise work with metals in some manner, and honestly, this group seems to be better versed in DIY stuff, so I wanted to throw my thoughts on the process of modding this mount plate, and getting the winch up in place.

Step #1. Disconnect connectors for off road lights, cut free zip ties restraining wiring to the brush guard.
Step #2. Remove brush guard main assembly leaving the upper mounts in place.
Step #3. Remove brush guard lower mounts. Reinstall bolts and D rings to frame of truck.
Step #4. Flip channel facing down, and with an assistant (beer paid friend), align channel to frame rail position desired. Using paint marker, mark position approx 1/2" in from the frame rails or any wiring. (I do NOT want ANY rubbing due to vibration).
Step #5. Take channel to bench, finish marking on both sides where the cuts are to go.
Step #6. Make necessary cuts with die grinder fitted with an arbor, and cut off wheel.
Step #7. Using angle grinder and grinding wheel, deburr, and round off any rough edges / corners.
Step #8. Using angle grinder and flap wheel, feather back finish 1/2" or so from work area on channel.
Step #9. Dab on touch of white paint on each bolt to be used to hold this together.
Step #10. With assistant, line the thing up facing up and forward, and press the channel into the bolt heads as straight as possible. Lower it back down so you now have the bolt area identified / marked.
Step #11. Using a center punch, and hammer, find the center of each bolt hole, and center punch the hole allowing it to be drilled accurately.
Step #12. Using calipers, determine the hole size of the plate. Select appropriate size drill bit 1 size up to allow for slight adjustment.
Step #13. Drill 4 needed holes, using drilling & tap oil to keep bit from burning up.
Step #14. Wipe clean with acetone and tack rags.Allow to dry. Burn acetone rags in fire pit.
Step #15. Prime with self etching primer.
Step #16. Paint with Rustoleum gloss black. I have several cans. Wait for at least an hour between coats, lay on 3 or 4 good coats.
Step #17. Allow paint to fully cure. (Wait several days if not week or so...).
Step #18. One paint is fully cured, assemble winch onto channel.
Step #19. Remove D rings and bolts from truck frame.
Step #20. using a pair of floor jacks, risers made with 4x4 scrap, and an assistant, lift winch and channel assembly into place.
Step #21. Assemble winch channel, D rings, and Brush Guard lower mounts to frame with mounting bolts. Tighten to Ford factory specs.
Step #22. Measure, mark and cut for opening for roller fairlead.
Step #23. Install roller fairlead making any opening adjustments needed.
Step #24. Reinstall brush guard main section to lower and upper mount brackets. torque to specs.
Step #25. Reconnect wiring terminals for off road lights.
Step #26. Feed cable out through fairlead, and install hook end.
Step #27. Make wiring connections to vehicle battery.
Step #28. Pay out cable. Using tree strap, draw cable back in under load to test winch and mount.
Step #29. Once verified secure hook to D ring on truck, remove last bit of slack. and go have a beer.

[cabinetman]

You could use an ordinary hack saw, or a reciprocating saw with a metal cutting blade, or a jig saw with a metal cutting blade, or a band saw with a metal cutting blade. The operating speeds on any of these should be slow. The metal can be dressed with a stone dressing wheel on a drill, or a grinder with a stone wheel. A mill file can soften the edges.

.

[dbhost]

Jig saw sounds a LOT better to me than the shower of sparks that will come from that cut off wheel!

Any recommendations for a jig saw blade?

Home Depot has the DeWalt DW3720-5 that looks about right. Is that on the right track?

I don't mind a few sparks during the dressing operation. It's the constant shower of sparks cutting that bothers me...

[Black wallnut]

Cabinetman pretty much nailed it. Abrasive cut off wheels cut steel pretty fast. You might be able to rent a plasma cutter to do a real neat job but I think it might be less money to just pay a metal shop to do it for you. If you have a small (or even a large) angle grinder you can get cut-off wheels for them as well and they cut fast.

[Lonnie in Orlando]

I vote for a $9.99 Harbor Freight 4-1/2" grinder (always on sale) and a cut off wheel for metal. Mark the cut line with a scratch or with the edge of a piece of tape. The cut off wheel will do a pretty good job of smoothing up the final edge. Finish up with a file. Secure the piece firmly in a vice.

I usually make increasingly deeper passes along the cut line until I cut through. Be careful about overcutting at the junction of the two cuts.

- Lonnie

[cabinetman]

Jig saw sounds a LOT better to me than the shower of sparks that will come from that cut off wheel!

Any recommendations for a jig saw blade?

Home Depot has the DeWalt DW3720-5 that looks about right. Is that on the right track?

I didn't know what type of mount your saw takes, but that DeWalt ought to do it. One of my suppliers carry Bosch and Lenox, which are both very good. You may need more than one blade.

.

[cabinetman]

a band saw with a metal cutting blade. The operating speeds on any of these should be slow.

I should make note in using a band saw, that if you have a wood cutting band saw, it may not be configured to run slow enough to cut metals, even with a metal cutting blade.

It should be running 300 RPM's blade speed, or less and it's wise to lubricate the cut. Changing the pulleys is a possibility.

.

[JSUPreston]

Another vote for the angle grinder. If you decide to do a tape line, also mark the cut line with a silver marker of some sort, since the tape line may get messed up or come off with the air coming off the grinder.

If you have one of the small cut off wheels, you may want to make multiple passes. It may take longer, but I think you'll have less clean up and an easier job than trying to use a jig saw.

[dbhost]

I have an angle grinder, not a big deal to use it, but not sure where to get cut off wheels for it, or what they even look like. I do know the ones for the die grinder...

Are the cutting disks you are talking about just the regular abrasive disks that the angle grinder comes with? I know those will cut REALLY fast...

[JSUPreston]

My grinder came with the stones. The cutoff wheels look more like this: http://www.harborfreight.com/pack-of...tal-45430.html

The stones are more for grinding down things, although I've found that I prefer a flap wheel for that.

[Mr__Bill]

...... reciprocating saw with a metal cutting blade......

.

This has always worked well for me. Get a good blade with the right number of teeth/inch for the thickness of the metal. And the trick is... don't rest the saw against the metal, it will vibrate your hands off. Rather saw with the saw as the blade reciprocates. Pushing and pulling the saw greatly reduces the vibration. When done dress the cut with the angle grinder.

Bill
it's always much easier when someone else does it.

[cwsmith]

It's been all too long since I've done any metal working. I have an angle grinder and surely it's the tool to use for "grinding", cutting away bolts, etc.; but, I'd be awfully hesitant in using it to cut sheet steel, as I'd be concerned about binding/busting a cut-off wheel. Those things spin at pretty high RPM and like any "circular" saw, once the cut-off wheel is in the kerf, you risk a kick-back. I think if forced to use that tool, I'd have a padded leather apron and a face shield. At that high RPM, any binding can be tough to control.

A metal cutting blade on a recip or even a jig saw might work okay, but I'm sure it would be slower and possibly rather jagged.

I'm wondering about a carborumdom (sp?) metal cutting blade on a small circular saw. The cut would be straight and a lot smoother and much better controlled than on either a high-speed grinder or a recip saw. If you do get a kick-back because of binding, the lower RPM of the circular saw would be easier to handle I feel.

But above all of those, I think the best, and perhaps the most pain free option is to look to a local shop. They'll have the equipment and a lot more experience to cut and then dress the edges for you (especially if this is just a one-time project).

If you do have to dress the edge yourself, a good mill file will do the trick and the you can smooth it further with good ol' emerery paper.

I hope this helps,

CWS

[Pappy]

Cut it to shape with a cutting wheel on a 4" or 4 1/2" grinder. HD and Lowes sells them in both sizes. My pereference is to get the Norton wheels from HD. Seem to last longer.

Finish off with a flap sanding disc. They are available from 36 to 120 grit depending how 'finished you want the final results. Probably an 80 g would get the results you want.

http://www.lowes.com/pd_385159-70-DW...isc&facetInfo=

[chopnhack]

Pappy has the winning combination. That is the the most common way any metalworker would approach the situation. It is also imho the quickest way to take care of what you are doing. Wear gloves, clamp the piece in place and put on a face mask or welder mask if you have one, hat for your head, respirator if you have one and grind away

[dbhost]

Okay gents. I have the winch mount plate completed, and the winch mounted to it. It all sits in my shop as I have to turn my attention to cleaning up shop, and ripping down sheet rock. My sub panel / circuit install is next Friday. After all these years of building this shop, I FINALLY get proper power!

All that is left cutting / grinding wise is slotting the bumper for the fairlead. I am going to install the roller fairlead in the space normally kept for the front license plate, and the plate will install on a special license plate bracket that mounts to the fairlead. I will paint the fairlead black in hopes that cosmetically it doesn't stand out too much from a stock license plate bracket. I figure the rigidity of the fairlead should outweight the compromise of integrity of the bumper by slotting it... Plus the added brush guard helps...