What's the goin rate to smooth down a manifold (6 cylinder)? I Was quoted $70-$120, depending on the condition. Is it just me or does that seem high?
Oh. Yep. Exhuast. Don't yall read minds? Anyway, there is no gasket, and #6 cylinder has a large leak that I dont think just a gasket will take care of.
$70 is really cheap for any milling job and the $120 sounds about right. Have the shop narrow down the price, setup is the biggest expense and once they have it on the machine it just takes another pass to clean it up.
That's what I was thinking. I have surfaced my own v8 manifolds on my wood working belt sander before. I have seen belt sanders in most body shops that are a lot larger than what I had so I would think they would be long enough to handle a straight 6 manifold. Shouldn't take them 10 minutes to smooth it out. clint
Having been a machinest for 40 yrs. just thought I would chime in and give some food for thought. The milling machine is a precision piece of equiptment that is very accurate and the fininsh can be regulated too. Surface grinding will all depend on the grit of the stone and is a bit more messy, with coolant and such. These machine's all depend on operator set-up, for accuracy and also experience in the trade. For an exhaust manifold that has a sealing gasket, a hand held surface grinder could be used, but not "not by me". Same goes for a belt sander, just cannot see getting an accurate surface, end to end, and side to side. Everybody has a level of doing things, either the quality way or the least expensive way. Just compare the Chinese goods that are taking over our retail outlet's and what used to be "American" made. Remember the old saying, "Pay me now or pay me later" P.S. I still won't use a Fram oil filter. JMO
Old Guy I think you are thinking of a different type of grinder then frank. Yes I do alot of machine work and surface grinders are one of the things I run, they are high precision machines that are very accurate if set up correctly. As are the milling machines. The one he is assuming is a surface grinder is one of these http://www.farrisequipment.com/headandblocksurfacersmillsgrinders/ it is made specifically for doing heads and blocks. All you do is set the basic fixtures for the head or block you are doing and it is all pre-set. So the setup can be as little as 5-10 min. Oh also if you use a CBN or Borazon wheel you do not need coolant.
What old guy said was that the finish depends on the stone on the surface grinder. It is a lot of work to change stones, dress the new one and set it up to do a single manifold. A surfacing mill uses carbide cutters and the feed can be controlled to change the finish. A regular vertical or horizontal mill could also be used.
The newer machines use CBN or Borazon wheels like I said http://www.ind.nortonabrasives.com/..._line_edit.asp?ele_ch_id=L0000000000000003959 http://www.georgiagrindingwheel.com/superabrwheelshapes.htm there is little setup and usually a dressing stone is integrated into the machine, the CBN wheels require minimal maintinance in comparison to the older stones. We use Jig grinders and center grinders where you can replace the stones, the machine dresses it automatically and you are cutting parts within 10 minutes. Technology has sped up the grinding setups directly. On our big grinders we use for grinding Tungsten Carbide coated hydraulic pistons it takes roughly 6 hours to change one of the CBN or diamond grinding wheels but on average running 3 shifts (7 days a week) they last about 6 months for the roughing stones and 8-9 months for the finish stones. It's kind of funny the last head I did on a Manual mill was a 4.2L AMC on an old Bridgeport series I. I had to use a trepan cutter because it was the only way I had enough travel to get the whole head in one shot
