How To Make Leather Upholstered Seats -Tuck and Roll Upholstery.
One thing that will really set a model apart from the rest in a contest especially in the larger scales is seats and interior panels upholstered in real leather with actual foam padding underneath. In this tutorial, I will show how to upholster a bucket seat in leather in the tuck and roll pattern using the seat that came with the kit. There are other ways to make the seat base but in this case, the kit seat was quite thick allowing modification without resorting to scratch building another base. Since this tutorial involves a great deal of information, to avoid confusion, Iíll break it up into several sections. The pictures below follow from left to right and top row to bottom row.
Seat Base Preparation
. Photo 1 shows the right and left seat bases and backs. The right side shows the original unmodified kit parts while the left side shows the same parts cut down 2mm all the way around to make room for the foam and leather covering. This correct cut-down is essential if the final product is to be the correct size and remain in scale. In other words, what you cut away should equal the height of your foam and leather stripping which in this 1/12 scale model is 2mm. Other scales will of course have different heights.
The first thing to do is use a saw like cutting wheel in a tool to make 2mm deep guide cuts in a number of areas. Photo 2 shows the cutting wheel I used with a 2mm depth mark. The wheel is sunk into the plastic up to the marking in a number of places. See Photo 3. Take your time and donít rush this step. You donít want to generate a lot of heat and melt the plastic instead of cutting it. After you have your guide cuts, remove all the plastic above the cut depths using the and then smooth the base with wet/dry sandpaper or sandsticks. Photo 4 shows some of the different burs you can use. The result should look like the original shape except 2mm smaller all the way around. Photos 5, 6, 7. Your base surface must be smooth and bump or pot hole free or youíll wind up high and low uneven spots in your final product. If you wind up with a hole in the base or a very thin area, you can always back it up with a piece of and contour.
Another way to make a base and back is to them out of plastic, Sculpey, wood or whatever you can find cut to the kit seat dimensions minus 2mm on each side.
Selecting and Preparing the Leather Covering
Now for the fun part. There are many different types of leather stock you can find but not all of them are acceptable for this type of application. Some have the wrong surface texture and look way out of scale. Some stock is way too thick or way too stiff and wonít conform to tight contours. Some leathers are too weak and will tear when you look at them wrong. Your ideal leather choices would be goatskin or kid leather which is very soft yet durable enough for modeling applications. Their biggest advantage is the usable surface skin can actually be peeled away from the deeper leather layers resulting in an ultra thin and uniform piece. The disadvantages of goatskin and kid leather are that they can be expensive, tear easily if you peel them incorrectly and usually only found on ladies gloves. The size of the available pieces once you take the gloves apart may be a bit small for some applications. The whole glove may not be usable because of seams and other ďdefectsĒ. You may need a number of sets of the same gloves and that can add up in the money department if the gloves are not on sale or clearance. Also, not all the colors you might want are available in leather gloves. Still, all is not lost. There are other good alternatives that give a beautiful result.
One good choice is soft leather like you see on various pieces of furniture and coats. Theyíre usually cow or horse hide since the pieces are available in large sections. Now I donít advocate tearing your couch or leather clothes apart especially if your significant other still needs them. You can go to furniture stores and see if they have some old swatches theyíre willing to part with. Furniture stores that may be closing down many times are willing to just give you their swatches rather than throw them out. They also have discontinued colors and textures that you can use. They may ask you to buy the old swatches but the price many times is low enough to make it worth the trouble. Sometimes you can get lucky like I did and get 2 shopping bags full of large swatches but thatís a bit rare. A second great source of leather is to make friends with your local upholsterer. He or she may have tons of scrap leather in a number of usable textures and sizes just waiting to be discarded. Another source of acceptable leather stock is old discarded couches and chairs you may see left out for disposal. If you have a good pair of scissors and/or a pocket knife, cut off as much as you need. Just make sure that couch or chair is definitely being thrown out. You donít want any problems with the neighbors. A final source is a leather craft store if there happens to be one somewhere in your surrounding neighborhoods. This is your most expensive alternative. You can get some very nice leather stock in larger sheets but expect to pay a whopping premium. I saw a great piece of goatskin in a store but the price was $120 bucks and it wasnít all that big. Unfortunately, fabric stores usually donít stock leather. You can substitute vinyl which is way less expensive but that will be shown in a later tutorial. Itís basically about the same as with the leather technique.
Skiving your leather
When you have chosen your leather, youíll usually find that itís sometimes too thick to apply directly to your seat base even in the larger scales. Youíll need to thin the piece down to get it to conform to your base and be the correct scale thickness. Thatís usually somewhere between 1/64Ē and 1/128 ď thick which is not difficult at all to get. Photo 8. The thinning process is called skiving and is usually done with a tool called a skife. For our purposes, you wonít have to go searching for a new tool. You can use an X-acto knife with a #10 blade which has a curved edge. Photo 9. The only thing is that the blades do dull easily and unless you have unlimited resources youíll want to invest in a good sharpening stone. That way, you can get a lot of life out of one blade. Weíll talk about sharpening your blades a bit later in this series.
I will try to explain how to successfully skive a piece of leather, but the technique requires a lot of practice. Youíll need to learn how to feel your work through the knife. Iíve been doing this since I was a kid and Iíve experimented on my own for quite a while developing the right technique. You really need to see it done in a video but unfortunately I donít have that capability at this time. You can find some brief ďhow toísĒ on YouTube but they donít get down to the ultra thin sections we need for modeling. The absolute best way to learn would be a one on one session with a tutor. Still, learning by yourself from this tutorial will not prevent you from doing a good job. Just please donít be discouraged. Sooner or later, youíll get the hang of it and do well. It does take some time.
You start your skiving by placing the leather skin-side down on a hard, flat surface like a piece of glass or a thick 8Ē x 10Ē piece of sheet metal. Photo 10. You want to hold your blade relatively horizontal but at a slight angle. In other words, the blade tip should be down slightly when compared to the handle. Photo 11. With a sideways motion pushing away from you like youíre trying to fillet a fish, cut into the leather but try not to go too deep. Pull the blade back and cut again. The leather should look like this. Photo 12. As you thin out your piece, youíll notice your surface will get lighter and lighter in color. Photo 13. Do this over the whole piece and try not to cut through and make a hole. Do not try to cut to your final thickness in one swipe. Thin the leather out gradually. Photo 14. Believe me, in the beginning, youíll make loads of holes. As experienced as I am, I still make holes. Keep practicing and experimenting with your knife positions and donít give up.
Sharpening Your Skiving Blades
I decided to include this subject in the skiving tutorial so it wouldnít get lost somewhere on the site.
Blade sharpening is not difficult at all and saves a great deal of money on blade replacements. You can sharpen one of the X-Acto blades until it disappears altogether. Photo 15. The key to getting a good sharp edge is the type of sharpener you use. Mechanical sharpeners are good for some applications but usually donít accommodate the small blades we use. Also, they leave the edges rough so they wonít cut well and will destroy your leather especially in the sections. Your best bet is to get a good sharpening stone with a fine surface. The photos show several different types and where you can get them. Theyíre generally not expensive and work very well with a good technique. Photos 16, 17, 18, 19.
First make sure your stone is wet. Some of the stones require you to presoak them first. The water serves as a lubricant and flushes all the metal debris off the stone. You can sharpen without the water but your stone will get clogged and wonít work well. Your blade edge should be set flat on the stone with the cutting edge facing forward. Photo 20. Push your blade forward a number of times making sure you turn the blade to cover the curve. Your final stroke should be forward so that any edge swarf will be removed. Flip the blade over and do the same.
After a number of sharpening, your edge will tend to thicken. Photo 21. Thin the edge back down with a stone in a and then re-sharpen your blade.
Applying the Leather to the Seat
In order to get that padded feel, youíll need to apply your leather to a strip of foam and then glue it down to the seat base. First, cut a straight piece of foam about the same width as your roll. For this particular seat, the roll should be 3mm wide. Then cut a strip of .010 the same width as your foam and glue the foam to the strip. Photo 22, 23. The glue I use is a rubber adhesive named ďGooĒ from the Walther Company. It works really well but any similar glue will do just as well. Photo 24. You spread a thin layer of the glue on both the foam and the , let it dry for about 2 minutes and then stick the two pieces together. Next, take a strip of leather the correct length and about 3 times the width of your foam and plastic piece, spread your adhesive on both surfaces, let dry for 2 minutes and press the foam to the leather. Wrap the sides of the excess leather over the sides of your foam and then glue the whole piece to the seat starting directly in the middle. Photo 25, 26, 27, 28. That way, youíll always have even rolls on each side of the middle. Your strip ends must also be glued down to the base so they donít stick up and ruin your effect. Youíll ultimately cover the end areas with another strip of leather. Continue adding strips until you cover the entire top surface. Photo 29. The sides of the seat are completed by cutting a piece of foam the same shape as the seat side. Cover that piece of foam with another piece of leather but you donít need a strip of underneath. The final seat side is made by cutting a .010 piece smaller than the seat side and covering the with leather. Photo 30. You donít need foam underneath that piece. Glue that to the seat side. The blue is a very thin wrapping wire I got at Radio Shack. Glue that down with some thin CA.
The next step is to glue down the cut down back cushion to the back of the kit seat. Skive a larger piece of leather and gently stretch and glue it directly to the plastic. Photo 31, 32. After that, continue to cut strips and cover the back until you are done. A final strip of leather was added to the top of the seat to cover the unsightly strip ends. The last step is to paint the base of the seat semi gloss black. That part will be set in the shadows so no further detailing would be necessary. The final product can be seen in photos 33, 34, 35.
This concludes my seat upholstery tutorial. In the next tutorial, Iíll go over how to upholster the side panels which has some different challenges to overcome.