jnshk
05-28-2012, 01:38 PM
DIY Door Panels: Part One
http://www.somethingsquare.com/temp/project_fail/doorpanels/963_0398x.jpg
Those look great! What material are they made of? What did you use to cut them?
1/8" thick ABS sheet. Check your local Yellow Pages for plastics/material suppliers. You can get it online too, but shipping a large sheet of plastic is almost always cost-prohibitive unless you plan to work with a large economy of scale. Lexan is another viable material, but more expensive and I'm not sure how well it responds to adhesives for attaching a vinyl or fabric covering.
The ABS pretty workable material (it can be cut with aviation snips, scored and broken with razor blades or glass/tile cutters, drilled, filed, sanded, heated and shaped, etc.) but I've found some methods that work better than others. This is my second set of door panels that I've cut, and the method I used this time was far more successful than my first attempts. The process this time was as follows (and should apply to any variation of NA door panel, as long as you've got a template or old door panel to work from):
1. Trace template onto ABS.
2. Cut panel outline using handheld jigsaw w/ "plastic cutting" blade. PROTIP: Apply firm pressure and rip through the material quickly. If you move too slowly the blade will start melting the material rather than cutting it. You really do not want to deal with this.
*2b. Cut the notches for the tabs at the top of the panels after cutting the main shape. Removing the material this way is much easier than trying to make all those short sharp angles with the jigsaw while you're cutting the panel out of the sheet material.
3. File, sand, smooth outline as necessary.
4. Double-check positioning and shape against template, then trace door handle hole, speaker hole, and any other large openings needed.
5. To cut large holes, use a holesaw or large diameter drill bit to make a starting point, then use the jigsaw to cut just inside of the lines.
6. Clean up the hole(s) with a dremel grinding wheel, hand file, and sandpaper as needed.
7. Double-check positioning and shape against template, then mark all holes to be drilled for door panel clips or retaining screws.
8. Drill as necessary.
9. Check fitment against door, then repeat this process for the matching panel. Use some spring clamps to line up and hold the panels together, then use this first panel as a guide when you mark and cut and drill your holes for the second panel.
* If you are using factory clips like I am, you will need to create a "snow man" shaped hole. Drill a 3/16" pilot hole at the "final position" of the clips, then if it all looks lined up properly, drill it out to 1/4". Now mark a point ~3/8" offset from the hole and drill another pilot hole. Step this hole up to 9/16" with the drill--I recommend a unibit (I like the Irwin Cobalt bits, but even the cheap Harbor Freight bits will work well) to save time and keep the overlapping holes clean.
Once you've got your holes drilled/shaped for the clips, you will need to remove some material because the 1/8" thick plastic is slightly too thick for the clips. There are probably a few ways of going about this, but I used a dremel with a medium sized (1/2" diameter) grinding stone wheel to do it. If you've never done this before, then you may want to practice on some scrap material because this is more art than science. What you want to do is to bring the top of the wheel directly down on the plastic to remove material in roughly a 1/2"circle around the clip hole so that it can slip onto the panel and slide into place.
What follows are my best attempts at tips for the dremel countersinking process:
- Watch and adjust the dremel speed as necessary. You want to be mostly grinding, with perhaps a hint of melting because you will inevitably have some melting, but you want to AVOID MELTING THE PLASTIC as much as possible. There's a fine line in balancing the dremel speed and the applied pressure. Too little speed and it will bog down, too much speed and it will melt right through everything. If in doubt, it's better to remove too little than to remove too much.
- Start the process by bringing the dremel down flat on the hole, then lift it to make sure that you're reasonably well centered. If it's all good, start grinding away material and "wobble" the dremel slightly in order to eject the plastic particles that are being removed from the material. If you do not do this, you will just start melting things without actually removing much of any material.
- Try to get a circle around the hole countersunk, and if things start getting too hot and melting, move to another hole and come back after it has had time too cool off a little bit. Make your circles around the holes first, then use the same techniques to extend the countersunk area to your larger hole openings, so that there are no bottlenecks or humps in the thickness of the material to prevent the clip from sliding into place. You want to bottleneck between the 1/4" hole and the 9/16" hole to keep the clip in place, not the thickness of the material.
- Since you will inevitably have some melting occur, use an x-acto knife or similar razor to trim the melted globs off and clean up the holes. They should break free with enough pressure, but if they are firmly melted in place the razor should be able to cut the material.
As you can see, my panel is currently uncovered and unfinished. I know there are some write-ups on covering the door panels on various Miata forums, but if there's not one here by the time I get around to it then I will add that step to this thread as well.
A note on alternative attachment methods: If you just want to leave the plastic panels uncovered, you may want to mount some rivnuts into a few of the clip holes on the door and just use some screws with finish washers to bolt the door panel in place. I haven't looked at the measurements, but I'm guessing that a 1/4" knurled rivnut would work well for this. This would be much more attractive than trying to reuse the stock door panel clips.
http://www.somethingsquare.com/temp/project_fail/doorpanels/963_0398x.jpg
Those look great! What material are they made of? What did you use to cut them?
1/8" thick ABS sheet. Check your local Yellow Pages for plastics/material suppliers. You can get it online too, but shipping a large sheet of plastic is almost always cost-prohibitive unless you plan to work with a large economy of scale. Lexan is another viable material, but more expensive and I'm not sure how well it responds to adhesives for attaching a vinyl or fabric covering.
The ABS pretty workable material (it can be cut with aviation snips, scored and broken with razor blades or glass/tile cutters, drilled, filed, sanded, heated and shaped, etc.) but I've found some methods that work better than others. This is my second set of door panels that I've cut, and the method I used this time was far more successful than my first attempts. The process this time was as follows (and should apply to any variation of NA door panel, as long as you've got a template or old door panel to work from):
1. Trace template onto ABS.
2. Cut panel outline using handheld jigsaw w/ "plastic cutting" blade. PROTIP: Apply firm pressure and rip through the material quickly. If you move too slowly the blade will start melting the material rather than cutting it. You really do not want to deal with this.
*2b. Cut the notches for the tabs at the top of the panels after cutting the main shape. Removing the material this way is much easier than trying to make all those short sharp angles with the jigsaw while you're cutting the panel out of the sheet material.
3. File, sand, smooth outline as necessary.
4. Double-check positioning and shape against template, then trace door handle hole, speaker hole, and any other large openings needed.
5. To cut large holes, use a holesaw or large diameter drill bit to make a starting point, then use the jigsaw to cut just inside of the lines.
6. Clean up the hole(s) with a dremel grinding wheel, hand file, and sandpaper as needed.
7. Double-check positioning and shape against template, then mark all holes to be drilled for door panel clips or retaining screws.
8. Drill as necessary.
9. Check fitment against door, then repeat this process for the matching panel. Use some spring clamps to line up and hold the panels together, then use this first panel as a guide when you mark and cut and drill your holes for the second panel.
* If you are using factory clips like I am, you will need to create a "snow man" shaped hole. Drill a 3/16" pilot hole at the "final position" of the clips, then if it all looks lined up properly, drill it out to 1/4". Now mark a point ~3/8" offset from the hole and drill another pilot hole. Step this hole up to 9/16" with the drill--I recommend a unibit (I like the Irwin Cobalt bits, but even the cheap Harbor Freight bits will work well) to save time and keep the overlapping holes clean.
Once you've got your holes drilled/shaped for the clips, you will need to remove some material because the 1/8" thick plastic is slightly too thick for the clips. There are probably a few ways of going about this, but I used a dremel with a medium sized (1/2" diameter) grinding stone wheel to do it. If you've never done this before, then you may want to practice on some scrap material because this is more art than science. What you want to do is to bring the top of the wheel directly down on the plastic to remove material in roughly a 1/2"circle around the clip hole so that it can slip onto the panel and slide into place.
What follows are my best attempts at tips for the dremel countersinking process:
- Watch and adjust the dremel speed as necessary. You want to be mostly grinding, with perhaps a hint of melting because you will inevitably have some melting, but you want to AVOID MELTING THE PLASTIC as much as possible. There's a fine line in balancing the dremel speed and the applied pressure. Too little speed and it will bog down, too much speed and it will melt right through everything. If in doubt, it's better to remove too little than to remove too much.
- Start the process by bringing the dremel down flat on the hole, then lift it to make sure that you're reasonably well centered. If it's all good, start grinding away material and "wobble" the dremel slightly in order to eject the plastic particles that are being removed from the material. If you do not do this, you will just start melting things without actually removing much of any material.
- Try to get a circle around the hole countersunk, and if things start getting too hot and melting, move to another hole and come back after it has had time too cool off a little bit. Make your circles around the holes first, then use the same techniques to extend the countersunk area to your larger hole openings, so that there are no bottlenecks or humps in the thickness of the material to prevent the clip from sliding into place. You want to bottleneck between the 1/4" hole and the 9/16" hole to keep the clip in place, not the thickness of the material.
- Since you will inevitably have some melting occur, use an x-acto knife or similar razor to trim the melted globs off and clean up the holes. They should break free with enough pressure, but if they are firmly melted in place the razor should be able to cut the material.
As you can see, my panel is currently uncovered and unfinished. I know there are some write-ups on covering the door panels on various Miata forums, but if there's not one here by the time I get around to it then I will add that step to this thread as well.
A note on alternative attachment methods: If you just want to leave the plastic panels uncovered, you may want to mount some rivnuts into a few of the clip holes on the door and just use some screws with finish washers to bolt the door panel in place. I haven't looked at the measurements, but I'm guessing that a 1/4" knurled rivnut would work well for this. This would be much more attractive than trying to reuse the stock door panel clips.