Heat gun useful? Gluing in cold workshop and other stuff

[Ttrees]

Hi folks
I originally started a best heat gun thread in the Buying advice/Tool review section,
As I haven't seen a thread about it, (admittedly I haven't tried searching in the archives, which I'm about to do)
Scrapped that thought though, as it would be much more useful to have a thread that gets derailed into much more useful discussions.
Besides the the best buying advice would be to purchase some insulation

Anyway, Looking to get a heat gun today and wonder if any folks might do the same in a pinch?
Hoping I can get away with warming these long timbers up before gluing in my uninsulated workshop.
I can do a good bit of work to the core after that, and leave off gluing more laminations until next year.
maybe work on some small parts and glue inside the house.

I just about got away with the last lamination the other day without the heater, although I was in there keeping the place somewhat warm.

The Parkside (Lidl) infrared thermometer gave me a reading of something like 15 degrees Celsius on all timbers to be glued.
I don't know if these need to be calibrated, because it seems like it was 11 or 12 degrees on the cheap wall thermometers.
Are these things any good at all?

I might try putting a tent up around the timber, aswell as warming my clamps up on the lously range beforehand if the heat gun won't do the job as well or in time.
Probably gonna have to take off the top of the bench and dung it out to get oil radiators underneath.

Do you guys think its feasible for a heat gun to cover this long of an area?
Was looking at the DeWalt which is top of the budget, it has a ceramic part inside so might last a bit longer without melting?
There's a 2000w Guild one in Argos for less than half the price....(yes I know there was a recall but that could be from some nitwit putting it away hot)
Looking to buy this if its still available, as the dewalt is really stretching it for me at 55 euros.

Thanks for your insight folks
Tom

 

[thetyreman]

I only use a heatgun when it's below 10 degrees C, I don't use an expensive one, it's an old bosch, didn't see the need in spending a lot of money on one, they are useful and seem to improve the bonding and decrease curing time especially with PVA.

 

[Droogs]

I've used an Earlex for about 20 years

 

[Ttrees]

Aye Ben, I was looking for a Bosch one in Homebase but only the DeWalt and Ryobi at the same price, and a lesser
brand for about 10 or 15 less.
Nowhere else seems to sell them where I'm at, and I don't wish to buy one online.
The length of the timbers is what makes me think the DeWalt one might fit the bill better.

Tom

 

[Ttrees]

Droogs, had a quick look at the Earlex one there, looks promising as many folks mention heat guns as a throw away item.
I must have a more indepth look at the thing.
Would you think it's up to the task for this length, as was guessing it would be cold on one end by the time I have heated the other?

 

[user22161]

For those long lengths, I would tent them up with a fan heater for an hour or so.

 

[Rich C]

The Parkside (Lidl) infrared thermometer gave me a reading of something like 15 degrees Celsius on all timbers to be glued.
I don't know if these need to be calibrated, because it seems like it was 11 or 12 degrees on the cheap wall thermometers.
Are these things any good at all?

Did you set the emissivity appropriately? They normally come preset to 0.95 (concrete / black paint) or 0.9 (red brick). Planed wood should be around 0.9.

 

[Ttrees]

Hello Rich C
I had a look at an emissivity factor chart and "wood" had a factor of 0.95
I'm not sure what the newish Powerfix Lidl one I have is preset to, nor if I can change it.
I will take it down to 0.95 if I can, and report back.
I wonder if that will make a difference?
Regardless I think I will still take those readings with a pinch of salt.
Thanks

 

[Ttrees]

For those long lengths, I would tent them up with a fan heater for an hour or so.

I don't have one of those, but the folks have a cheap one, aswell as having a halogen type moving one.
You reckon either would be superior performance compared to two oil radiators...
Using one on at a time alternating?

Or is it for the less faff involved not having to take the top of the bench off and dung out underneath?

Tom

 

[user22161]

For those long lengths, I would tent them up with a fan heater for an hour or so.

I don't have one of those, but the folks have a cheap one, aswell as having a halogen type moving one.
You reckon either would be superior performance compared to two oil radiators...
Using one on at a time alternating?

Or is it for the less faff involved not having to take the top of the bench off and dung out underneath?

Tom

Oil are the safest but are convector heaters so heat goes up before dispersing, halogen are likely to be a fire risk with concentrated directed heat whereas a fan heater is more likely to direct heat along the tent. Unless very cold, my 14 x 17ft workshop heats up quite well for working on low fan heater setting, IIRC 750w.

 

[Rich C]

Hello Rich C
I had a look at an emissivity factor chart and "wood" had a factor of 0.95
I'm not sure what the newish Powerfix Lidl one I have is preset to, nor if I can change it.
I will take it down to 0.95 if I can, and report back.
I wonder if that will make a difference?
Regardless I think I will still take those readings with a pinch of salt.
Thanks

I have pointed mine (not a Lidl one) at copper pipes and had a huge difference (20-30C) between the correct emissivity and the incorrect one.

 

[Phil Pascoe]

I have one of these over my bench. it's brilliant as if I need a bit of warmth I put it on for an hour or two beforehand on 600w but if (as usual my circulation being poor) my hands get cold the heat on full is pretty much immediate. I don't attempt to heat the whole workshop.
https://www.primrose.co.uk/firefly-18kw ... =list_name
(no, its not 18kw )

 

[Ttrees]

Thanks folks
I should state that I don't plan on having a system for throughout the winter.
I can get a lot done once the core is in one lump, and can do other things for winter.
Fire risk is of no concern as I can clean the workshop.
I think the wall hanging option would be better for directing heat downwards rather than trying to
heat from underneath, which seems more sensible for 4" thick timber.

I done a small bit of research on those infrared thermometers.
The consensus being that they won't give an accurate reading on shiny surfaces.
Commonplace it seems, to use a bit of black tape to get the proper reading on shiny or smooth surfaces.
Maybe that's what I should do.
From what I've read most are set default emissivity level at 0.96 I think.
I will check this out further when I find the manual.
Haven't found much good info on youtube about them yet,
Only finding the same kind of videos for both the infrared thermometer and the heat guns. :roll:

Think I'm gonna spring for the DeWalt now.
Cheers.

Tom

 

[Droogs]

I would suggest getting a couple of infrared heaters. they would be ideal to warm up the surface. I have one and when its on full i can feel that it has warmed up the router table and the drill press about 3m away compared to the other bits of kit in the shop

 

[samhay]

I have one of these over my bench...
https://www.primrose.co.uk/firefly-18kw ... =list_name
(no, its not 18kw )

Sorry for the hijack, but how hot do these get? Essentially, can you burn yourself on the grill?

Back to the OP. I have used a hot air gun to warm up the timber before a glue up. Not sure it helped much. Heater would be my preference.

 

[Phil Pascoe]

You'd undoubtedly burn yourself if you touched it. I'd think that or something similar would be more efficient at warming your work up than any hot air gun.

 

[samhay]

Thanks.
Not ideal somewhere with limited headroom then.

 

[Ttrees]

Guess i should have waited a while longer so as I bought the DeWalt one.
I thought it would/hope it will be a massive aid to get the chill off the timber along with the two oil rads underneath.

Just seen a 2000w heater in home base that looks like a good yoke. Compact and rugged but 80 quid. There's the halogen ones for thirty but have no thermal mass to them.
looks like the other has a bit as it's encased in a metal box.

Gonna try and find the manual for the infrared thermometer so I will be back with my findings.
I wonder how much potential penetrated heat will be lost when the tent is lifted off.
I don't have a big enough tent to be under myself unfortunately.
Happy to hear some more tips and opinions.
Thanks for the replies guys.
Tom

 

[samhay]

Wood had quite high thermal mass (specific heat capacity).
Takes a long time to heat up, but also takes a long time to cool down again. If you leave it under the tent for long enough to actually heat up then you should be good for a glue up.

 

[Ttrees]

That's what I was thinking, especially with thicker timbers.
I did notice that the glue was still curing well when applied,
but noticed when unclamping after at least 24 hours, some glue
did not set inbetween spots that I couldn't get access to clean with a wet rag.
So guessing the thermal mass has dropped significantly.

It seems that lifting the tent will make no difference, as long as the timbers are warmed sufficiently.
The question is what temperature of the timbers would I be wanting to achieve that would make negligible difference when lifting the tent briefly?

I can't find the metal encased heater on the Homebase website
It looks like a guitar practice amp (maybe a bit on the larger side) from looking at the box, I didn't open it.
If I had the money I would think about springing for it.

Please feel free to talk about your heaters and whatnot, it's all interesting to me.
Thanks folks
Tom