Engineers to the front please.......

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MasterofHera

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Its another mast problem. Mast is down and I need to fit new electrics. Plus add Radar. Cant shift the old cables to run a mouse down inside. Need to remove the mast foot. Will attempt to drill out the 4 bolts. So what drills do I need and can I buy cutting fluid in small amounts? The mast is a Proctor. Seems filled with polly beads. Any other blockages up inside? All advice welcomed. Local machine shops closed down due to lack of work so cannot just cart it up the road.
Helpppppppppppppp
 
For drilling out screws, I like left handed drills. I think Northern Tool sell them. The bit will often grab and undo the screw. I've used them a lot for loctited screws up to M4 with great success, a few times on larger.
You probably have stainless-in-alloy corrosion, it will not be easy!
Plenty of heat will help, I tend to use a hot air gun, doesn't run out of gas like a blowlamp.
Drilling stainless needs sharp drills, buy some new ones! The TiN coated ones seem good for stainless.
Good luck!
 
You don't say what size the bolts are or why you are having to drill them out. I'm guessing that they are 8/10mm thread and stainless steel that have corroded in place. I suggest that you use new HSS (High Speed Steel) drills and start with a 4mm diameter pilot hole and work upwards 1mm at a time. Keep a steady pressure on the drill so that you keep a constant ribbon of swarf - some stainless can harden as you cut it so you need to keep the cutting edge behind the hardened material on the surface.

You will need lubricant/coolant but for a few holes like this you don't need anything sophisticated. Mix new engine oil 50:50 with paraffin and dab plenty on with a brush as you drill - best to get someone to help and don't forget eye protection for both of you.

Good luck
 
Left handed drills .....April 1st was a couple of weeks ago. Tried Northern tools site nothing available. Would love to think your idea is cosher as the principal is sound. Yes agree corrosion plus Loctite will be the problem.
 
Thanks Nigel. My idea entirely same as yours ...looking to buy HSS tomorrow ..moving up from 4 in steady increments.
Tried with 5mm HSS this pm with 14V drill not a lot of luck so will revert to 240v. Like your idea for the cooling oil.
 
I wouldn't worry too much about cutting fluid - anything like wd40, oil, white spirit, paraffin etc will do. As lw395 says the TiN ones are good. Use a very slow speed, try and make sure you drill centrally and straight down the axis of the bolt. Start small and work up to the correct size - if the hole is off centre you'll have to stop sooner, but if you're lucky you may be able to punch out the remains.
You may have some luck using stud extractors ('easy-outs') but they've never worked for me on the stainless/aluminium combination.
If all else fails, grind off the heads, drill down the exposed bolt shank as far as the mast is thick, and you should be able to knock the foot off. You could then drill and tap new fixings, or take the offending article to a machine shop to have the bolts milled out. Best of luck - I've just spent several hours doing much the same thing on my roller reefing drum.

ps Use Duralac when you re-assemble!
 
LH drills are used industrially, usually in multi-spindle machines. Many DIY drills have a chuck mounted on a RH thread. That combination would be good for April 1st.
 
I use a cordless drill which seems fairly immune to coming apart when used for undoing hefty woodscrews etc. Your point is worth considering, I hadn't thought of it!
This does sound like a drill it out situation, not one where the LH drills will work like magic, but I find them miles better than the spiral stud extractors. Duralac is good, but copper grease or low strength loctite are better than nothing.
 
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Duralac is good, but copper grease or low strength loctite are better than nothing.

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I wouldn't use a copper based grease anywhere near aluminium. If you haven't got Duralac then use ordinary grease instead.
 
H_M, Just a thought....Had a similar problem removing the mast heel. Found removing the headbox turned out to be a doddle and gave access to what I needed.
 
ACF-50 is the business for breaking down corrossion, I've used it many times on alloy to alloy corroded parts, some that haven't moved for over 10 years and they free up in a day or two.
Motor bike shops have been stocking it, or search, there was a new supplier at seaworks last year.
Its also known as corrosion block.
 
I have found for drilling out stainless steel that standard high speed steel drills are not very good.
Try high speed steel + 8% cobalt. They cost about 3 times standard high speed steel drills but are ace on spring/ss. /forums/images/graemlins/cool.gif
 
And for a relatively easy stress free drilling experience..
Beg or borrow a drill press and lug it out to the mast and drill in situ with nice low rpm and a steady pressure on the drill arm...
About half way through first drilling out the first bolt with a handheld drill,this idea will start to seem quite attractive,imo .
 
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Plus add Radar

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Just as a thought, why mount the radar up the mast.

My experience - and I really am no expert, is that the higher you mount the radar, the more sea clutter when there is anything of a chop. You end up seeing next to nothing and only the big stuff.

Do you really want 15-20 miles range. I tend to use 6 - 10 miles at adbolute max - so why mount it high with all the associated problems of wiring?

Just a thought.....
 
There is no worry drilling out stainless screws bolts etc.
Use normal HSS. the key is, centre punch FIRST, then use small drill and go up in size to achive what you need.
The other most important thing when drilling SS is to use a very SLOW speed, and lots of pressure.. DONT let the drill smoke.
I have never had to use cutting compund or lubricant for this.
Had to take our mast foot off in 05, a similar job.

I wish you well
 
SS and Aluminium is not a good combination and I would never suggest a copper based lubricant for SS, anyway. Mast fixings shouild be Monel, both pop rivits and engineering screws.

Monel is slightly easier to machine than SS but the important things are Hard, Sharp Drills (std HSS lasts no time at all) and slow speeds. I used six new drills to remove four monel fixings last winter.....

I've not tried WD40 but spray-on 3 in 1 lubricant was OK as a cutting fluid. You must keep the drill bit cool, so cold water will do at a pinch.
 
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